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000
FXUS65 KRIW 231021
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
321 AM MST SUN NOV 23 2014

.SHORT TERM...SUNDAY THROUGH TUESDAY NIGHT

WITH THE DIFFERENCES IN THE WEATHER ACROSS THE AREA WE WILL ONCE
AGAIN DIVIDE THE DISCUSSION INTO WEST AND EAST OF THE DIVIDE.

WEST OF THE DIVIDE...THE FINAL SHORTWAVE WITH CURRENT SYSTEM IS
CURRENTLY BRINGING SOME LIGHT TO MODERATE SNOW TO THE AREAS WITH THE
WARNINGS CONTINUING. WITH THE ECHOES CONTINUING WE WILL CONTINUE THE
HIGHLIGHTS UNTIL THEY END AT 6 AM THIS MORNING. THE REMAINDER OF THE
DAY LOOKS TO BE MOSTLY CLOUDY WITH LINGERING SNOW SHOWERS ALTHOUGH
ANY FURTHER ACCUMULATIONS ARE EXPECTED TO BE MINOR.

ANOTHER SHORTWAVE THEN DROPS IN FROM THE NORTH AND WEST TONIGHT WITH
THE ANOTHER CHANCE OF SNOW. THIS ONE LOOKS A LITTLE WEAKER AND DOES
NOT HAVE AS MUCH UPPER LEVEL SUPPORT. NEVERTHELESS...IT LOOKS LIKE A
GOOD CHANCE FOR MORE ACCUMULATING SNOW. AT THIS TIME...CONTINUITY
LOOKED REASONABLE WITH AROUND 3 TO 6 INCHES IN THE MOUNTAINS WITH
THE HIGHEST AMOUNTS IN THE LOCATIONS THAT FAVOR NORTHWEST OROGRAPHIC
FLOW. THE VALLEYS LOOK TO HAVE 1 TO 3 INCHES OF NEW SNOW. SO...AT
THIS TIME IT LOOKS TO REMAIN UNDER ADVISORY CRITERIA. THE BEST LIFT
WILL SHIFT EAST OF THE AREA BY MONDAY MORNING WITH MORE UPSLOPE SNOW
SHOWERS OCCURRING THROUGH THE DAY ON MONDAY INTO MONDAY EVENING.

THE NEXT IN THE SERIES OF SYSTEMS THEN MOVES IN FOR TUESDAY FROM THE
NORTH AND WEST. THIS ONE LOOKS TO HAVE A BIT MORE PUNCH THEN THE
MONDAY SYSTEM. THE MODELS DO BEGIN TO DIVERGE AT THIS POINT. THE GFS
AND EUROPEAN MODELS START BRINGING IN PRECIPITATION LATER MONDAY
NIGHT WHILE THE NAM IS SLOWER...HOLDING OFF THE PRECIPITATION UNTIL
TUESDAY. FOR NOW...WE COMPROMISED IN BRINGING PRECIPITATION IN FOR
MONDAY NIGHT BUT HOLDING OFF THE HEAVIEST UNTIL TUESDAY. THE GFS
ALSO HAS BETTER LIFT OVER THE AREA. THE NAM IS A BIT WEAKER WITH THE
JET AND KEEPS THE BEST LIFT ACROSS MONTANA. FOR NOW...THE MAJORITY
RULES SO WE WILL KEEP THE WETTER SOLUTION. HOWEVER...THERE IS A FAIR
AMOUNT OF UNCERTAINTY.

EAST OF THE DIVIDE...THE RADAR IS MAINLY QUIET FOLLOWING THE PASSAGE
OF THE COLD FRONT. THE MAIN CONCERN HERE SHIFTS FROM SNOW TO WIND.
THE MODELS HAVE TRENDED DOWN WITH THE WIND ACROSS PORTIONS OF THE
WIND RIVER BASIN. 700 MILLIBAR WINDS THAT WERE AROUND 50 TO 55 KNOTS
YESTERDAY HAVE TRENDED DOWNWARD TO 35 KNOTS SO CANCELING THE HIGH
WIND WATCH LOOKS LIKE A GOOD CALL AT THIS POINT. HOWEVER...THERE
WILL STILL BE A GUSTY NORTHWEST WIND WITH GUSTS TO NEAR 50 MPH
POSSIBLE. WE WILL CONTINUE THE HIGH WIND WARNING FOR NORTHERN
JOHNSON COUNTY WITH A COMBINATION OF 50 KNOT 700 MILLIBAR WINDS...A
TIGHT PRESSURE GRADIENT AND A FAVORABLE NORTHWEST FLOW BEING THE
FACTORS FOR IT. SOME LIGHT SNOW WILL FALL ACROSS THE BIGHORNS BUT
NOTHING OF CONSEQUENCE. TEMPERATURES WILL BE COLDER THAN
YESTERDAY...BUT NOTHING UNUSUAL FOR NOVEMBER IN WYOMING.

THE NEXT SYSTEM WILL TRY TO IMPACT THE AREA ON MONDAY.
HOWEVER...MUCH LIKE THE LAST SYSTEM...DOWNSLOPING FLOW WILL LIKELY
TAKE MOST OF THE MOISTURE. THERE IS SOME CONCERN THAT SOME COULD
SNEAK EAST OF THE DIVIDE SINCE WINDS ARE NOT AS STRONG AS THE
PREVIOUS SYSTEMS. AS A RESULT WE HAVE ISOLATED POPS IN FOR MOST
AREAS. IT WILL STILL BE BREEZY AS WELL...ALTHOUGH NOT AS BREEZY AS
THE PREVIOUS COUPLE OF DAYS. THE EXCEPTION AGAIN MAY BE NORTHERN
JOHNSON COUNTY WHICH MAY HAVE TO BE WATCHED FOR HIGHER WINDS. THEN
EXPECT A LULL IN THE PRECIPITATION ON MONDAY NIGHT AS THE AREA WILL
BE IN BETWEEN SYSTEMS.

WE HAVE THE SAME DILEMMA FOR EAST OF THE DIVIDE AS WEST OF THE
DIVIDE FOR TUESDAY. THE MODELS ARE STILL SPLIT AS FOR COVERAGE OF
PRECIPITATION WITH THE NAM DRY AND THE GFS AND EUROPEAN WETTER. FOR
NOW...WE HAVE LEFT CONTINUITY ALONE FOR THE MOST PART WITH SLIGHT
CHANCE TO CHANCE POPS ACROSS NORTHERN AREAS WHERE THE BEST LIFT WILL
BE. THE OTHER CONCERN WILL BE FOR WIND ON TUESDAY. ALL THE MODELS
STRENGTHEN 700 MILLIBAR WINDS TO OVER 50 KNOTS ACROSS MUCH OF THE
AREA TUESDAY AFTERNOON AND TUESDAY EVENING. THIS...ALONG WITH THE
RIGHT FRONT QUADRANT OF A POTENT JET MAX PASSING TO THE NORTH MAY
ENHANCE DOWNWARD FORCING AND BRING GUSTY TO POSSIBLY STRONG WINDS
FOR TUESDAY AHEAD OF THE TROUGH AND ASSOCIATED FRONT...ESPECIALLY TO
AREAS THAT FAVOR STRONG WINDS WITH SOUTHWEST FLOW. THIS MEANS FROM
ROCK SPRINGS THROUGH CASPER. NEVERTHELESS...A LOT TO WATCH OVER THE
NEXT FEW DAYS.

.LONG TERM...WEDNESDAY THROUGH SUNDAY

CHALLENGING MEDIUM RANGE PERIOD WITH MODELS STRUGGLING ON HOW MUCH
ENERGY WILL DIVE SWD OUT OF CANADA AND TO SOME EXTENT WHEN. THE
GFS IS THE MOST OPTIMISTIC IF YOU WANT A QUIET/DRY THANKSGIVING.
THE ECMWF AND GEM HAVE A SERIES OF SEWD MOVING SHORTWAVES
COMBINING WITH A SURFACE HIGH THAT FORMS ON THE BACK SIDE OF A SWD
MOVING SHORTWAVE ON THE WEST SIDE OF THE HUDSON BAY LOW. THE ECMWF
AND GEM ARE SHARPLY COLDER THURSDAY AND FRIDAY ACROSS THE NORTH
AND EAST. THE GEM IS FASTEST WITH THE FIRST SHORTWAVE WITH A
CHANCE OF SNOW JUST ABOUT EVERYWHERE WEDNESDAY NIGHT INTO
THANKSGIVING DAY WITH H7 TEMPERATURES FALLING TO AS COLD AS -15C
TO -17C ACROSS THE NORTH DURING THE DAY. THE ECMWF IS A LITTLE
SLOWER WITH COLDEST AIR FILTERING IN THURSDAY AND THURSDAY NIGHT
WITH H7 TEMPS OF -15 TO -19C BY LATER THURSDAY NIGHT AND FRIDAY IN
THE NORTH. THE FRONT MAKES IT DOWN TO MOST IF NOT ALL AREAS EAST
OF THE DIVIDE ON THURSDAY BUT THE COLDEST MID LEVEL AIR ARRIVES A
LITTLE LATER. ON THE OTHER HAND...THE GFS HAS A MILD THANKSGIVING
DAY WITH ABOVE 0C H7 AIR IN MOST OF THE AREA WITH HIGHS LIKELY TO
BE IN THE 50S EAST OF THE DIVIDE WITH AT LEAST 30S AND 40S WEST.
JUST ONE EXAMPLE IS THE MEX GUIDANCE GIVING CPR 53 ON THURSDAY
WHILE THE EURO GUIDANCE HAS 27. ON FRIDAY...THE MEX HAS 53 AGAIN
FOR CPR WHILE THE EURO HAS 12. THE ECMWF ENSEMBLES SUPPORT THE OP
ECMWF WITH A LITTLE LESS AMPLIFICATION WHILE MOST OF THE GFS
ENSEMBLE MEMBERS FAVORING THE OP GFS...BUT NOT ALL. THE GFS
FINALLY BRINGS IN A STRONG COLD FRONT ACROSS THE NORTH AND EAST
BUT NOT UNTIL SOME TIME FRIDAY OR FRIDAY NIGHT. RIGHT NOW LEANING
TOWARDS AN INITIAL SHALLOW FIRST SYSTEM ACROSS AT LEAST THE NORTH
ON THANKSGIVING WITH THE SECOND SYSTEM BRINGING DOWN THE COLDEST
AIR WHEN COMBINED WITH A SHORTWAVE MOVING INTO THE NRN HIGH PLAINS
THAT DEVELOPS A STRONG SURFACE HIGH. THE COMBINATION OF THE
SHORTWAVE FROM THE B.C. AREA DIVING SE OVER US WITH THIS STRONG
SURFACE HIGH WILL LIKELY LEAD TO FAIRLY STRONG UPSLOPE EAST OF THE
DIVIDE WITH SHARPLY COLDER AIR AND SOME LIGHT SNOW. AHEAD OF THIS
SYSTEM...STRONG NW FLOW WILL KEEP SOME LIGHT TO MODERATE SNOW
GOING IN THE NRN MOUNTAINS ON WEDNESDAY. TURNING COLDER THEN
THANKSGIVING DAY INTO FRIDAY WITH A CHANCE OF SNOW...ESPECIALLY
NORTH AND EAST. BY THE WEEKEND...SOME PACIFIC MOISTURE GETS DRAWN
INTO THE WEST AS A UPPER LOW MOVES TOWARDS OR ONTO THE WEST COAST
WHILE SHORTWAVES CONTINUE TO DIVE SE INTO THE NRN HIGH PLAINS
KEEPING A COLD FRONT IN THE VICINITY OF OUR NRN AND ERN ZONES. SO
A BUSY EXTENDED PERIOD WITH THE POTENTIAL FOR TRAVEL TO BE
IMPACTED AT TIMES. NOTHING POINTING TO A MAJOR SNOWSTORM BUT JUST
ENOUGH WEATHER AND COLD TEMPS AT TIMES TO POTENTIALLY HAMPER
TRAVEL AT TIMES.

&&

.AVIATION.../12Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES
VFR CONDITIONS WILL PREVAIL THROUGH MID-MORNING SUNDAY BEHIND A COLD
FRONT THAT MOVED THROUGH THE AREA SATURDAY EVENING.  AN UPPER LEVEL
DISTURBANCE WILL SPREAD SHSN INTO THE BIGHORN RANGE...FRQT MTN
OBSCURATIONS BY 18Z SUNDAY WITH ISOLD TO WIDELY SCT MVFR -SHSN
MAINLY VCNTY AND EAST OF A KCOD-KWRL-KCPR LINE.  NW SFC WINDS WILL
INCREASE WITH THIS SYSTEM MID TO LATE SUNDAY MORNING WITH WIND GUSTS
OVER 50KTS EXPECTED ALONG AND NORTH OF THE I90 CORRIDOR.  FURTHER
WEST...SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL OCCUR
ACROSS THE WIND RIVER BASIN...VCNTY KRIW.  WINDS WILL DECREASE BUT
REMAIN GUSTY IN THESE AREAS SUNDAY NIGHT.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES
A WEAK UPPER LEVEL DISTURBANCE WILL SLIDE ACROSS W-SW WYOMING EARLY
THIS MORNING SPREADING AREAS OF MVFR/IFR -SN AND MTN OBSCURATIONS
INTO VCNTY KJAC-KAFO THROUGH AROUND 13Z.  A BAND OF MVFR/IFR SNOW IS
ALSO LIKELY TO MOVE EAST ALONG THE INTERSTATE 80 CORRIDOR...VCNTY
KRKS THROUGH 15Z.  A DRIER AIRMASS WILL FOLLOW LATE SUNDAY MORNING
AND SUNDAY AFTERNOON WITH SOME LINGERING SNOW SHOWERS OBSCURING
MTNS.  GUSTY NW SFC WINDS AT 20-30KTS WILL ALSO DEVELOP BEHIND THIS
SYSTEM DURING THE DAY SUNDAY ACROSS THE UPPER GREEN RIVER BASIN AND
ALONG THE INTERSTATE 80 CORRIDOR.  A MOIST WESTERLY FLOW WILL SPREAD
AREAS OF MVFR/IFR -SN BACK INTO THE WEST...MAINLY VCNTY AND NORTH OF
A KEMM-KPNA LINE SUNDAY NIGHT.
&&

.FIRE WEATHER...

TEMPERATURES WILL BE COLDER TODAY WITH HIGHER HUMIDITY AND LOW
MIXING HEIGHTS WITH POOR SMOKE DISPERSAL. LINGERING SNOW SHOWERS
WILL FALL ACROSS WESTERN WYOMING TODAY. STRONG WINDS ARE POSSIBLE
ACROSS PORTIONS OF NORTHERN JOHNSON COUNTY. ANOTHER SYSTEM MOVING IN
FROM THE WEST WILL BRING ADDITIONAL SNOW SHOWERS TONIGHT INTO EARLY
MONDAY.
&&

.RIW WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 6 AM MST EARLY THIS MORNING
WYZ012-013-023-024.

HIGH WIND WARNING UNTIL 5 PM MST THIS AFTERNOON WYZ010.

&&

$$

SHORT TERM...HATTINGS
LONG TERM...SKRBAC
AVIATION...AEM
FIRE WEATHER...HATTINGS










000
FXUS65 KRIW 231021
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
321 AM MST SUN NOV 23 2014

.SHORT TERM...SUNDAY THROUGH TUESDAY NIGHT

WITH THE DIFFERENCES IN THE WEATHER ACROSS THE AREA WE WILL ONCE
AGAIN DIVIDE THE DISCUSSION INTO WEST AND EAST OF THE DIVIDE.

WEST OF THE DIVIDE...THE FINAL SHORTWAVE WITH CURRENT SYSTEM IS
CURRENTLY BRINGING SOME LIGHT TO MODERATE SNOW TO THE AREAS WITH THE
WARNINGS CONTINUING. WITH THE ECHOES CONTINUING WE WILL CONTINUE THE
HIGHLIGHTS UNTIL THEY END AT 6 AM THIS MORNING. THE REMAINDER OF THE
DAY LOOKS TO BE MOSTLY CLOUDY WITH LINGERING SNOW SHOWERS ALTHOUGH
ANY FURTHER ACCUMULATIONS ARE EXPECTED TO BE MINOR.

ANOTHER SHORTWAVE THEN DROPS IN FROM THE NORTH AND WEST TONIGHT WITH
THE ANOTHER CHANCE OF SNOW. THIS ONE LOOKS A LITTLE WEAKER AND DOES
NOT HAVE AS MUCH UPPER LEVEL SUPPORT. NEVERTHELESS...IT LOOKS LIKE A
GOOD CHANCE FOR MORE ACCUMULATING SNOW. AT THIS TIME...CONTINUITY
LOOKED REASONABLE WITH AROUND 3 TO 6 INCHES IN THE MOUNTAINS WITH
THE HIGHEST AMOUNTS IN THE LOCATIONS THAT FAVOR NORTHWEST OROGRAPHIC
FLOW. THE VALLEYS LOOK TO HAVE 1 TO 3 INCHES OF NEW SNOW. SO...AT
THIS TIME IT LOOKS TO REMAIN UNDER ADVISORY CRITERIA. THE BEST LIFT
WILL SHIFT EAST OF THE AREA BY MONDAY MORNING WITH MORE UPSLOPE SNOW
SHOWERS OCCURRING THROUGH THE DAY ON MONDAY INTO MONDAY EVENING.

THE NEXT IN THE SERIES OF SYSTEMS THEN MOVES IN FOR TUESDAY FROM THE
NORTH AND WEST. THIS ONE LOOKS TO HAVE A BIT MORE PUNCH THEN THE
MONDAY SYSTEM. THE MODELS DO BEGIN TO DIVERGE AT THIS POINT. THE GFS
AND EUROPEAN MODELS START BRINGING IN PRECIPITATION LATER MONDAY
NIGHT WHILE THE NAM IS SLOWER...HOLDING OFF THE PRECIPITATION UNTIL
TUESDAY. FOR NOW...WE COMPROMISED IN BRINGING PRECIPITATION IN FOR
MONDAY NIGHT BUT HOLDING OFF THE HEAVIEST UNTIL TUESDAY. THE GFS
ALSO HAS BETTER LIFT OVER THE AREA. THE NAM IS A BIT WEAKER WITH THE
JET AND KEEPS THE BEST LIFT ACROSS MONTANA. FOR NOW...THE MAJORITY
RULES SO WE WILL KEEP THE WETTER SOLUTION. HOWEVER...THERE IS A FAIR
AMOUNT OF UNCERTAINTY.

EAST OF THE DIVIDE...THE RADAR IS MAINLY QUIET FOLLOWING THE PASSAGE
OF THE COLD FRONT. THE MAIN CONCERN HERE SHIFTS FROM SNOW TO WIND.
THE MODELS HAVE TRENDED DOWN WITH THE WIND ACROSS PORTIONS OF THE
WIND RIVER BASIN. 700 MILLIBAR WINDS THAT WERE AROUND 50 TO 55 KNOTS
YESTERDAY HAVE TRENDED DOWNWARD TO 35 KNOTS SO CANCELING THE HIGH
WIND WATCH LOOKS LIKE A GOOD CALL AT THIS POINT. HOWEVER...THERE
WILL STILL BE A GUSTY NORTHWEST WIND WITH GUSTS TO NEAR 50 MPH
POSSIBLE. WE WILL CONTINUE THE HIGH WIND WARNING FOR NORTHERN
JOHNSON COUNTY WITH A COMBINATION OF 50 KNOT 700 MILLIBAR WINDS...A
TIGHT PRESSURE GRADIENT AND A FAVORABLE NORTHWEST FLOW BEING THE
FACTORS FOR IT. SOME LIGHT SNOW WILL FALL ACROSS THE BIGHORNS BUT
NOTHING OF CONSEQUENCE. TEMPERATURES WILL BE COLDER THAN
YESTERDAY...BUT NOTHING UNUSUAL FOR NOVEMBER IN WYOMING.

THE NEXT SYSTEM WILL TRY TO IMPACT THE AREA ON MONDAY.
HOWEVER...MUCH LIKE THE LAST SYSTEM...DOWNSLOPING FLOW WILL LIKELY
TAKE MOST OF THE MOISTURE. THERE IS SOME CONCERN THAT SOME COULD
SNEAK EAST OF THE DIVIDE SINCE WINDS ARE NOT AS STRONG AS THE
PREVIOUS SYSTEMS. AS A RESULT WE HAVE ISOLATED POPS IN FOR MOST
AREAS. IT WILL STILL BE BREEZY AS WELL...ALTHOUGH NOT AS BREEZY AS
THE PREVIOUS COUPLE OF DAYS. THE EXCEPTION AGAIN MAY BE NORTHERN
JOHNSON COUNTY WHICH MAY HAVE TO BE WATCHED FOR HIGHER WINDS. THEN
EXPECT A LULL IN THE PRECIPITATION ON MONDAY NIGHT AS THE AREA WILL
BE IN BETWEEN SYSTEMS.

WE HAVE THE SAME DILEMMA FOR EAST OF THE DIVIDE AS WEST OF THE
DIVIDE FOR TUESDAY. THE MODELS ARE STILL SPLIT AS FOR COVERAGE OF
PRECIPITATION WITH THE NAM DRY AND THE GFS AND EUROPEAN WETTER. FOR
NOW...WE HAVE LEFT CONTINUITY ALONE FOR THE MOST PART WITH SLIGHT
CHANCE TO CHANCE POPS ACROSS NORTHERN AREAS WHERE THE BEST LIFT WILL
BE. THE OTHER CONCERN WILL BE FOR WIND ON TUESDAY. ALL THE MODELS
STRENGTHEN 700 MILLIBAR WINDS TO OVER 50 KNOTS ACROSS MUCH OF THE
AREA TUESDAY AFTERNOON AND TUESDAY EVENING. THIS...ALONG WITH THE
RIGHT FRONT QUADRANT OF A POTENT JET MAX PASSING TO THE NORTH MAY
ENHANCE DOWNWARD FORCING AND BRING GUSTY TO POSSIBLY STRONG WINDS
FOR TUESDAY AHEAD OF THE TROUGH AND ASSOCIATED FRONT...ESPECIALLY TO
AREAS THAT FAVOR STRONG WINDS WITH SOUTHWEST FLOW. THIS MEANS FROM
ROCK SPRINGS THROUGH CASPER. NEVERTHELESS...A LOT TO WATCH OVER THE
NEXT FEW DAYS.

.LONG TERM...WEDNESDAY THROUGH SUNDAY

CHALLENGING MEDIUM RANGE PERIOD WITH MODELS STRUGGLING ON HOW MUCH
ENERGY WILL DIVE SWD OUT OF CANADA AND TO SOME EXTENT WHEN. THE
GFS IS THE MOST OPTIMISTIC IF YOU WANT A QUIET/DRY THANKSGIVING.
THE ECMWF AND GEM HAVE A SERIES OF SEWD MOVING SHORTWAVES
COMBINING WITH A SURFACE HIGH THAT FORMS ON THE BACK SIDE OF A SWD
MOVING SHORTWAVE ON THE WEST SIDE OF THE HUDSON BAY LOW. THE ECMWF
AND GEM ARE SHARPLY COLDER THURSDAY AND FRIDAY ACROSS THE NORTH
AND EAST. THE GEM IS FASTEST WITH THE FIRST SHORTWAVE WITH A
CHANCE OF SNOW JUST ABOUT EVERYWHERE WEDNESDAY NIGHT INTO
THANKSGIVING DAY WITH H7 TEMPERATURES FALLING TO AS COLD AS -15C
TO -17C ACROSS THE NORTH DURING THE DAY. THE ECMWF IS A LITTLE
SLOWER WITH COLDEST AIR FILTERING IN THURSDAY AND THURSDAY NIGHT
WITH H7 TEMPS OF -15 TO -19C BY LATER THURSDAY NIGHT AND FRIDAY IN
THE NORTH. THE FRONT MAKES IT DOWN TO MOST IF NOT ALL AREAS EAST
OF THE DIVIDE ON THURSDAY BUT THE COLDEST MID LEVEL AIR ARRIVES A
LITTLE LATER. ON THE OTHER HAND...THE GFS HAS A MILD THANKSGIVING
DAY WITH ABOVE 0C H7 AIR IN MOST OF THE AREA WITH HIGHS LIKELY TO
BE IN THE 50S EAST OF THE DIVIDE WITH AT LEAST 30S AND 40S WEST.
JUST ONE EXAMPLE IS THE MEX GUIDANCE GIVING CPR 53 ON THURSDAY
WHILE THE EURO GUIDANCE HAS 27. ON FRIDAY...THE MEX HAS 53 AGAIN
FOR CPR WHILE THE EURO HAS 12. THE ECMWF ENSEMBLES SUPPORT THE OP
ECMWF WITH A LITTLE LESS AMPLIFICATION WHILE MOST OF THE GFS
ENSEMBLE MEMBERS FAVORING THE OP GFS...BUT NOT ALL. THE GFS
FINALLY BRINGS IN A STRONG COLD FRONT ACROSS THE NORTH AND EAST
BUT NOT UNTIL SOME TIME FRIDAY OR FRIDAY NIGHT. RIGHT NOW LEANING
TOWARDS AN INITIAL SHALLOW FIRST SYSTEM ACROSS AT LEAST THE NORTH
ON THANKSGIVING WITH THE SECOND SYSTEM BRINGING DOWN THE COLDEST
AIR WHEN COMBINED WITH A SHORTWAVE MOVING INTO THE NRN HIGH PLAINS
THAT DEVELOPS A STRONG SURFACE HIGH. THE COMBINATION OF THE
SHORTWAVE FROM THE B.C. AREA DIVING SE OVER US WITH THIS STRONG
SURFACE HIGH WILL LIKELY LEAD TO FAIRLY STRONG UPSLOPE EAST OF THE
DIVIDE WITH SHARPLY COLDER AIR AND SOME LIGHT SNOW. AHEAD OF THIS
SYSTEM...STRONG NW FLOW WILL KEEP SOME LIGHT TO MODERATE SNOW
GOING IN THE NRN MOUNTAINS ON WEDNESDAY. TURNING COLDER THEN
THANKSGIVING DAY INTO FRIDAY WITH A CHANCE OF SNOW...ESPECIALLY
NORTH AND EAST. BY THE WEEKEND...SOME PACIFIC MOISTURE GETS DRAWN
INTO THE WEST AS A UPPER LOW MOVES TOWARDS OR ONTO THE WEST COAST
WHILE SHORTWAVES CONTINUE TO DIVE SE INTO THE NRN HIGH PLAINS
KEEPING A COLD FRONT IN THE VICINITY OF OUR NRN AND ERN ZONES. SO
A BUSY EXTENDED PERIOD WITH THE POTENTIAL FOR TRAVEL TO BE
IMPACTED AT TIMES. NOTHING POINTING TO A MAJOR SNOWSTORM BUT JUST
ENOUGH WEATHER AND COLD TEMPS AT TIMES TO POTENTIALLY HAMPER
TRAVEL AT TIMES.

&&

.AVIATION.../12Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES
VFR CONDITIONS WILL PREVAIL THROUGH MID-MORNING SUNDAY BEHIND A COLD
FRONT THAT MOVED THROUGH THE AREA SATURDAY EVENING.  AN UPPER LEVEL
DISTURBANCE WILL SPREAD SHSN INTO THE BIGHORN RANGE...FRQT MTN
OBSCURATIONS BY 18Z SUNDAY WITH ISOLD TO WIDELY SCT MVFR -SHSN
MAINLY VCNTY AND EAST OF A KCOD-KWRL-KCPR LINE.  NW SFC WINDS WILL
INCREASE WITH THIS SYSTEM MID TO LATE SUNDAY MORNING WITH WIND GUSTS
OVER 50KTS EXPECTED ALONG AND NORTH OF THE I90 CORRIDOR.  FURTHER
WEST...SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL OCCUR
ACROSS THE WIND RIVER BASIN...VCNTY KRIW.  WINDS WILL DECREASE BUT
REMAIN GUSTY IN THESE AREAS SUNDAY NIGHT.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES
A WEAK UPPER LEVEL DISTURBANCE WILL SLIDE ACROSS W-SW WYOMING EARLY
THIS MORNING SPREADING AREAS OF MVFR/IFR -SN AND MTN OBSCURATIONS
INTO VCNTY KJAC-KAFO THROUGH AROUND 13Z.  A BAND OF MVFR/IFR SNOW IS
ALSO LIKELY TO MOVE EAST ALONG THE INTERSTATE 80 CORRIDOR...VCNTY
KRKS THROUGH 15Z.  A DRIER AIRMASS WILL FOLLOW LATE SUNDAY MORNING
AND SUNDAY AFTERNOON WITH SOME LINGERING SNOW SHOWERS OBSCURING
MTNS.  GUSTY NW SFC WINDS AT 20-30KTS WILL ALSO DEVELOP BEHIND THIS
SYSTEM DURING THE DAY SUNDAY ACROSS THE UPPER GREEN RIVER BASIN AND
ALONG THE INTERSTATE 80 CORRIDOR.  A MOIST WESTERLY FLOW WILL SPREAD
AREAS OF MVFR/IFR -SN BACK INTO THE WEST...MAINLY VCNTY AND NORTH OF
A KEMM-KPNA LINE SUNDAY NIGHT.
&&

.FIRE WEATHER...

TEMPERATURES WILL BE COLDER TODAY WITH HIGHER HUMIDITY AND LOW
MIXING HEIGHTS WITH POOR SMOKE DISPERSAL. LINGERING SNOW SHOWERS
WILL FALL ACROSS WESTERN WYOMING TODAY. STRONG WINDS ARE POSSIBLE
ACROSS PORTIONS OF NORTHERN JOHNSON COUNTY. ANOTHER SYSTEM MOVING IN
FROM THE WEST WILL BRING ADDITIONAL SNOW SHOWERS TONIGHT INTO EARLY
MONDAY.
&&

.RIW WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 6 AM MST EARLY THIS MORNING
WYZ012-013-023-024.

HIGH WIND WARNING UNTIL 5 PM MST THIS AFTERNOON WYZ010.

&&

$$

SHORT TERM...HATTINGS
LONG TERM...SKRBAC
AVIATION...AEM
FIRE WEATHER...HATTINGS








  [top]

000
FXUS63 KUNR 230927
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
227 AM MST SUN NOV 23 2014

.SHORT TERM...TODAY THROUGH MONDAY NIGHT
ISSUED AT 225 AM MST SUN NOV 23 2014

AT 08Z THE PACIFIC COLD FRONT HAD ALMOST COMPLETELY
MOVED OUT OF THE EASTERN EXTREMITIES OF THE FORECAST AREA.  THE
NE-SW BAND OF VERY LIGHT PRECIPITATION ACROSS WEST CENTRAL SOUTH
DAKOTA IS LIKELY THE RESULT OF MID LEVEL FRONTOGENESIS BEHIND THE
MAIN UPPER VORTICITY LOBE.  SURFACE TEMPERATURES WOULD SUPPORT THIS
BEING MOSTLY LIQUID PRECIP AT THIS TIME.  IR SATLT IMAGERY SEEMS TO
INDICATE THERE IS PROBABLY SOME VERY LIGHT PRECIPITATION OVER PARTS
OF SOUTHEASTERN MONTANA AND NORTHEAST WYOMING WHICH ISN`T SHOWING UP
ON RADAR IMAGERY BECAUSE THE TOPS ARE TOO LOW.

TODAY...THIS INSTABILITY PRECIP RESULTING FROM COLD ADVECTION ALOFT
WILL LIKELY CONTINUE THROUGH MOST OF THE DAY AND FILL IN BEHIND THE
FRONTAL PRECIP BY MID MORNING. ACCUMULATIONS SHOULD BE MINIMAL IN
THE LOWER ELEVATIONS...BUT A FEW INCHES OF NEW SNOW ARE POSSIBLE IN
THE HIGHER ELEVATIONS OF THE BLKHLS. THE MAIN WEATHER STORY WILL BE
THE STRONG NORTHERLY WINDS EXPECTED TO DEVELOP BEHIND THE UPPER
TROUGH EARLY THIS AFTERNOON. THE STRONGEST GRADIENT AND WIND SPEEDS
ARE EXPECTED BEWEEN 18Z AND 21Z OVER THE WESTERN PLAINS AND NORTH
AND NORTHEAST FOOTHILLS.

TONIGHT AND MONDAY...THE PATTERN WILL REMAIN A FAIRLY CONSTANT
NORTHWEST FLOW ALOFT WITH OCCASIONAL WEAK MID OR UPPER LEVEL
IMPULSES CROSSING THE REGION. A SLIGHT CHANCE OF MEASURABLE SNOW
WILL REMAIN IN THE FORECAST THROUGH MONDAY AND BEYOND.  MONDAY IS
EXPECTED TO BE THE COOLEST DAY OF THE WEEK WITH HIGHS ONLY REACHNG
THE LOW TO MID 30S MONDAY AFTERNOON.
&&

.LONG TERM...TUESDAY THROUGH SATURDAY
ISSUED AT 225 AM MST SUN NOV 23 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTHERN PLAINS THROUGH MIDWEEK.
SEVERAL WEAK DISTURBANCES WITHIN NORTHWEST FLOW WILL SLIDE
THROUGH...BRINGING A GOOD DEAL OF CLOUDINESS AND CHANCES FOR SNOW
SHOWERS AT TIMES THROUGH WEDNESDAY. THE BEST CHANCES FOR SNOW WILL
GENERALLY BE ACROSS NORTHEAST WY AND THE NORTHERN BLACK HILLS AREA.

FOR THE HOLIDAY PERIOD...MODELS CONTINUE TO HAVE A VERY DIFFICULT
TIME SETTLING ON THE FORECAST FROM THANKSGIVING INTO THE HOLIDAY
WEEKEND. THE 00Z GFS HAS GONE BACK TO A WARMER SOLUTION WHILE THE
ECM IS MUCH COLDER. THE ECM IS ALSO SHOWING SNOW LINGERING THROUGH
THE DAY THURSDAY. HAVE ADDED SLIGHT CHANCE POPS TO THE WRN 2/3 OF
THE CWA TO ACCOUNT FOR THIS...BUT WILL NOT ADD ANYMORE POPS PAST 00Z
FRI.

&&

.AVIATION...FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING
ISSUED AT 225 AM MST SUN NOV 23 2014

STRONG NORTHWEST WINDS ARE EXPECTED TODAY ESPECIALLY
ACROSS THE NW/WCNTRL SOUTH DAKOTA PLAINS. SHSN/MVFR CIGS ARE MOST
LIKELY ACROSS NW SD...THE BLKHLS...AND PORTIONS OF NE WY. LOCALIZED
IFR CIGS ARE EXPECTED WITH UPSLOPE ENHANCED SHSN OVER THE NRN BLKHLS.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY FROM 8 AM MST /9 AM CST/ THIS MORNING TO 8 PM MST
     /9 PM CST/ THIS EVENING FOR SDZ014-025-027-032-041-043-044-
     046-047-049.

     HIGH WIND WARNING FROM 8 AM THIS MORNING TO 8 PM MST THIS
     EVENING FOR SDZ001-002-012-013-026-031-072-073.

WY...NONE.
&&

$$

SHORT TERM...CARPENTER
LONG TERM...13
AVIATION...13







000
FXUS63 KUNR 230927
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
227 AM MST SUN NOV 23 2014

.SHORT TERM...TODAY THROUGH MONDAY NIGHT
ISSUED AT 225 AM MST SUN NOV 23 2014

AT 08Z THE PACIFIC COLD FRONT HAD ALMOST COMPLETELY
MOVED OUT OF THE EASTERN EXTREMITIES OF THE FORECAST AREA.  THE
NE-SW BAND OF VERY LIGHT PRECIPITATION ACROSS WEST CENTRAL SOUTH
DAKOTA IS LIKELY THE RESULT OF MID LEVEL FRONTOGENESIS BEHIND THE
MAIN UPPER VORTICITY LOBE.  SURFACE TEMPERATURES WOULD SUPPORT THIS
BEING MOSTLY LIQUID PRECIP AT THIS TIME.  IR SATLT IMAGERY SEEMS TO
INDICATE THERE IS PROBABLY SOME VERY LIGHT PRECIPITATION OVER PARTS
OF SOUTHEASTERN MONTANA AND NORTHEAST WYOMING WHICH ISN`T SHOWING UP
ON RADAR IMAGERY BECAUSE THE TOPS ARE TOO LOW.

TODAY...THIS INSTABILITY PRECIP RESULTING FROM COLD ADVECTION ALOFT
WILL LIKELY CONTINUE THROUGH MOST OF THE DAY AND FILL IN BEHIND THE
FRONTAL PRECIP BY MID MORNING. ACCUMULATIONS SHOULD BE MINIMAL IN
THE LOWER ELEVATIONS...BUT A FEW INCHES OF NEW SNOW ARE POSSIBLE IN
THE HIGHER ELEVATIONS OF THE BLKHLS. THE MAIN WEATHER STORY WILL BE
THE STRONG NORTHERLY WINDS EXPECTED TO DEVELOP BEHIND THE UPPER
TROUGH EARLY THIS AFTERNOON. THE STRONGEST GRADIENT AND WIND SPEEDS
ARE EXPECTED BEWEEN 18Z AND 21Z OVER THE WESTERN PLAINS AND NORTH
AND NORTHEAST FOOTHILLS.

TONIGHT AND MONDAY...THE PATTERN WILL REMAIN A FAIRLY CONSTANT
NORTHWEST FLOW ALOFT WITH OCCASIONAL WEAK MID OR UPPER LEVEL
IMPULSES CROSSING THE REGION. A SLIGHT CHANCE OF MEASURABLE SNOW
WILL REMAIN IN THE FORECAST THROUGH MONDAY AND BEYOND.  MONDAY IS
EXPECTED TO BE THE COOLEST DAY OF THE WEEK WITH HIGHS ONLY REACHNG
THE LOW TO MID 30S MONDAY AFTERNOON.
&&

.LONG TERM...TUESDAY THROUGH SATURDAY
ISSUED AT 225 AM MST SUN NOV 23 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTHERN PLAINS THROUGH MIDWEEK.
SEVERAL WEAK DISTURBANCES WITHIN NORTHWEST FLOW WILL SLIDE
THROUGH...BRINGING A GOOD DEAL OF CLOUDINESS AND CHANCES FOR SNOW
SHOWERS AT TIMES THROUGH WEDNESDAY. THE BEST CHANCES FOR SNOW WILL
GENERALLY BE ACROSS NORTHEAST WY AND THE NORTHERN BLACK HILLS AREA.

FOR THE HOLIDAY PERIOD...MODELS CONTINUE TO HAVE A VERY DIFFICULT
TIME SETTLING ON THE FORECAST FROM THANKSGIVING INTO THE HOLIDAY
WEEKEND. THE 00Z GFS HAS GONE BACK TO A WARMER SOLUTION WHILE THE
ECM IS MUCH COLDER. THE ECM IS ALSO SHOWING SNOW LINGERING THROUGH
THE DAY THURSDAY. HAVE ADDED SLIGHT CHANCE POPS TO THE WRN 2/3 OF
THE CWA TO ACCOUNT FOR THIS...BUT WILL NOT ADD ANYMORE POPS PAST 00Z
FRI.

&&

.AVIATION...FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING
ISSUED AT 225 AM MST SUN NOV 23 2014

STRONG NORTHWEST WINDS ARE EXPECTED TODAY ESPECIALLY
ACROSS THE NW/WCNTRL SOUTH DAKOTA PLAINS. SHSN/MVFR CIGS ARE MOST
LIKELY ACROSS NW SD...THE BLKHLS...AND PORTIONS OF NE WY. LOCALIZED
IFR CIGS ARE EXPECTED WITH UPSLOPE ENHANCED SHSN OVER THE NRN BLKHLS.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY FROM 8 AM MST /9 AM CST/ THIS MORNING TO 8 PM MST
     /9 PM CST/ THIS EVENING FOR SDZ014-025-027-032-041-043-044-
     046-047-049.

     HIGH WIND WARNING FROM 8 AM THIS MORNING TO 8 PM MST THIS
     EVENING FOR SDZ001-002-012-013-026-031-072-073.

WY...NONE.
&&

$$

SHORT TERM...CARPENTER
LONG TERM...13
AVIATION...13







000
FXUS63 KUNR 230927
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
227 AM MST SUN NOV 23 2014

.SHORT TERM...TODAY THROUGH MONDAY NIGHT
ISSUED AT 225 AM MST SUN NOV 23 2014

AT 08Z THE PACIFIC COLD FRONT HAD ALMOST COMPLETELY
MOVED OUT OF THE EASTERN EXTREMITIES OF THE FORECAST AREA.  THE
NE-SW BAND OF VERY LIGHT PRECIPITATION ACROSS WEST CENTRAL SOUTH
DAKOTA IS LIKELY THE RESULT OF MID LEVEL FRONTOGENESIS BEHIND THE
MAIN UPPER VORTICITY LOBE.  SURFACE TEMPERATURES WOULD SUPPORT THIS
BEING MOSTLY LIQUID PRECIP AT THIS TIME.  IR SATLT IMAGERY SEEMS TO
INDICATE THERE IS PROBABLY SOME VERY LIGHT PRECIPITATION OVER PARTS
OF SOUTHEASTERN MONTANA AND NORTHEAST WYOMING WHICH ISN`T SHOWING UP
ON RADAR IMAGERY BECAUSE THE TOPS ARE TOO LOW.

TODAY...THIS INSTABILITY PRECIP RESULTING FROM COLD ADVECTION ALOFT
WILL LIKELY CONTINUE THROUGH MOST OF THE DAY AND FILL IN BEHIND THE
FRONTAL PRECIP BY MID MORNING. ACCUMULATIONS SHOULD BE MINIMAL IN
THE LOWER ELEVATIONS...BUT A FEW INCHES OF NEW SNOW ARE POSSIBLE IN
THE HIGHER ELEVATIONS OF THE BLKHLS. THE MAIN WEATHER STORY WILL BE
THE STRONG NORTHERLY WINDS EXPECTED TO DEVELOP BEHIND THE UPPER
TROUGH EARLY THIS AFTERNOON. THE STRONGEST GRADIENT AND WIND SPEEDS
ARE EXPECTED BEWEEN 18Z AND 21Z OVER THE WESTERN PLAINS AND NORTH
AND NORTHEAST FOOTHILLS.

TONIGHT AND MONDAY...THE PATTERN WILL REMAIN A FAIRLY CONSTANT
NORTHWEST FLOW ALOFT WITH OCCASIONAL WEAK MID OR UPPER LEVEL
IMPULSES CROSSING THE REGION. A SLIGHT CHANCE OF MEASURABLE SNOW
WILL REMAIN IN THE FORECAST THROUGH MONDAY AND BEYOND.  MONDAY IS
EXPECTED TO BE THE COOLEST DAY OF THE WEEK WITH HIGHS ONLY REACHNG
THE LOW TO MID 30S MONDAY AFTERNOON.
&&

.LONG TERM...TUESDAY THROUGH SATURDAY
ISSUED AT 225 AM MST SUN NOV 23 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTHERN PLAINS THROUGH MIDWEEK.
SEVERAL WEAK DISTURBANCES WITHIN NORTHWEST FLOW WILL SLIDE
THROUGH...BRINGING A GOOD DEAL OF CLOUDINESS AND CHANCES FOR SNOW
SHOWERS AT TIMES THROUGH WEDNESDAY. THE BEST CHANCES FOR SNOW WILL
GENERALLY BE ACROSS NORTHEAST WY AND THE NORTHERN BLACK HILLS AREA.

FOR THE HOLIDAY PERIOD...MODELS CONTINUE TO HAVE A VERY DIFFICULT
TIME SETTLING ON THE FORECAST FROM THANKSGIVING INTO THE HOLIDAY
WEEKEND. THE 00Z GFS HAS GONE BACK TO A WARMER SOLUTION WHILE THE
ECM IS MUCH COLDER. THE ECM IS ALSO SHOWING SNOW LINGERING THROUGH
THE DAY THURSDAY. HAVE ADDED SLIGHT CHANCE POPS TO THE WRN 2/3 OF
THE CWA TO ACCOUNT FOR THIS...BUT WILL NOT ADD ANYMORE POPS PAST 00Z
FRI.

&&

.AVIATION...FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING
ISSUED AT 225 AM MST SUN NOV 23 2014

STRONG NORTHWEST WINDS ARE EXPECTED TODAY ESPECIALLY
ACROSS THE NW/WCNTRL SOUTH DAKOTA PLAINS. SHSN/MVFR CIGS ARE MOST
LIKELY ACROSS NW SD...THE BLKHLS...AND PORTIONS OF NE WY. LOCALIZED
IFR CIGS ARE EXPECTED WITH UPSLOPE ENHANCED SHSN OVER THE NRN BLKHLS.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY FROM 8 AM MST /9 AM CST/ THIS MORNING TO 8 PM MST
     /9 PM CST/ THIS EVENING FOR SDZ014-025-027-032-041-043-044-
     046-047-049.

     HIGH WIND WARNING FROM 8 AM THIS MORNING TO 8 PM MST THIS
     EVENING FOR SDZ001-002-012-013-026-031-072-073.

WY...NONE.
&&

$$

SHORT TERM...CARPENTER
LONG TERM...13
AVIATION...13







000
FXUS63 KUNR 230927
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
227 AM MST SUN NOV 23 2014

.SHORT TERM...TODAY THROUGH MONDAY NIGHT
ISSUED AT 225 AM MST SUN NOV 23 2014

AT 08Z THE PACIFIC COLD FRONT HAD ALMOST COMPLETELY
MOVED OUT OF THE EASTERN EXTREMITIES OF THE FORECAST AREA.  THE
NE-SW BAND OF VERY LIGHT PRECIPITATION ACROSS WEST CENTRAL SOUTH
DAKOTA IS LIKELY THE RESULT OF MID LEVEL FRONTOGENESIS BEHIND THE
MAIN UPPER VORTICITY LOBE.  SURFACE TEMPERATURES WOULD SUPPORT THIS
BEING MOSTLY LIQUID PRECIP AT THIS TIME.  IR SATLT IMAGERY SEEMS TO
INDICATE THERE IS PROBABLY SOME VERY LIGHT PRECIPITATION OVER PARTS
OF SOUTHEASTERN MONTANA AND NORTHEAST WYOMING WHICH ISN`T SHOWING UP
ON RADAR IMAGERY BECAUSE THE TOPS ARE TOO LOW.

TODAY...THIS INSTABILITY PRECIP RESULTING FROM COLD ADVECTION ALOFT
WILL LIKELY CONTINUE THROUGH MOST OF THE DAY AND FILL IN BEHIND THE
FRONTAL PRECIP BY MID MORNING. ACCUMULATIONS SHOULD BE MINIMAL IN
THE LOWER ELEVATIONS...BUT A FEW INCHES OF NEW SNOW ARE POSSIBLE IN
THE HIGHER ELEVATIONS OF THE BLKHLS. THE MAIN WEATHER STORY WILL BE
THE STRONG NORTHERLY WINDS EXPECTED TO DEVELOP BEHIND THE UPPER
TROUGH EARLY THIS AFTERNOON. THE STRONGEST GRADIENT AND WIND SPEEDS
ARE EXPECTED BEWEEN 18Z AND 21Z OVER THE WESTERN PLAINS AND NORTH
AND NORTHEAST FOOTHILLS.

TONIGHT AND MONDAY...THE PATTERN WILL REMAIN A FAIRLY CONSTANT
NORTHWEST FLOW ALOFT WITH OCCASIONAL WEAK MID OR UPPER LEVEL
IMPULSES CROSSING THE REGION. A SLIGHT CHANCE OF MEASURABLE SNOW
WILL REMAIN IN THE FORECAST THROUGH MONDAY AND BEYOND.  MONDAY IS
EXPECTED TO BE THE COOLEST DAY OF THE WEEK WITH HIGHS ONLY REACHNG
THE LOW TO MID 30S MONDAY AFTERNOON.
&&

.LONG TERM...TUESDAY THROUGH SATURDAY
ISSUED AT 225 AM MST SUN NOV 23 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTHERN PLAINS THROUGH MIDWEEK.
SEVERAL WEAK DISTURBANCES WITHIN NORTHWEST FLOW WILL SLIDE
THROUGH...BRINGING A GOOD DEAL OF CLOUDINESS AND CHANCES FOR SNOW
SHOWERS AT TIMES THROUGH WEDNESDAY. THE BEST CHANCES FOR SNOW WILL
GENERALLY BE ACROSS NORTHEAST WY AND THE NORTHERN BLACK HILLS AREA.

FOR THE HOLIDAY PERIOD...MODELS CONTINUE TO HAVE A VERY DIFFICULT
TIME SETTLING ON THE FORECAST FROM THANKSGIVING INTO THE HOLIDAY
WEEKEND. THE 00Z GFS HAS GONE BACK TO A WARMER SOLUTION WHILE THE
ECM IS MUCH COLDER. THE ECM IS ALSO SHOWING SNOW LINGERING THROUGH
THE DAY THURSDAY. HAVE ADDED SLIGHT CHANCE POPS TO THE WRN 2/3 OF
THE CWA TO ACCOUNT FOR THIS...BUT WILL NOT ADD ANYMORE POPS PAST 00Z
FRI.

&&

.AVIATION...FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING
ISSUED AT 225 AM MST SUN NOV 23 2014

STRONG NORTHWEST WINDS ARE EXPECTED TODAY ESPECIALLY
ACROSS THE NW/WCNTRL SOUTH DAKOTA PLAINS. SHSN/MVFR CIGS ARE MOST
LIKELY ACROSS NW SD...THE BLKHLS...AND PORTIONS OF NE WY. LOCALIZED
IFR CIGS ARE EXPECTED WITH UPSLOPE ENHANCED SHSN OVER THE NRN BLKHLS.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY FROM 8 AM MST /9 AM CST/ THIS MORNING TO 8 PM MST
     /9 PM CST/ THIS EVENING FOR SDZ014-025-027-032-041-043-044-
     046-047-049.

     HIGH WIND WARNING FROM 8 AM THIS MORNING TO 8 PM MST THIS
     EVENING FOR SDZ001-002-012-013-026-031-072-073.

WY...NONE.
&&

$$

SHORT TERM...CARPENTER
LONG TERM...13
AVIATION...13







000
FXUS65 KRIW 230636
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1134 PM MST SAT NOV 22 2014

.UPDATE...UPDATED TO ADD 06Z AVIATION DISCUSSION.

.UPDATE...SNOW HAS TAPERED OFF OR ENDED BEHIND A COLD FRONT ACROSS
MOST OF WESTERN WYOMING. ANOTHER SHORTWAVE MOVING EAST ACROSS
IDAHO WILL BRING ANOTHER SHOT OF LIGHT TO MODERATE SNOW INTO FAR
WEST WYOMING AFTER MIDNIGHT. CANCELLED WINTER HIGHLIGHTS FOR ALL
AREAS BUT JACKSON HOLE VALLEY...STAR VALLEY AND SURROUNDING
MOUNTAINS WHERE WINTER STORM WARNINGS REMAIN IN EFFECT UNTIL 6 AM
SUNDAY. COLD FRONT HAS ALSO ENDED THE HIGH WIND THREAT ACROSS
CENTRAL WYOMING...SO HIGH WIND WARNINGS WERE CANCELLED. UPGRADED
HIGH WIND WATCH TO A WARNING FOR ONLY NORTHEAST JOHNSON COUNTY ON
SUNDAY. LATEST MODEL RUNS NOT AS BULLISH WITH STRONG WINDS FURTHER
WEST ACROSS THE WIND RIVER BASIN.

&&

.PREV DISCUSSION... /ISSUED 210 PM MST SAT NOV 22 2014/

SHORT TERM...TONIGHT THROUGH SUNDAY

A PACIFIC COLD FRONT APPROACHING WESTERN WYOMING WILL MOVE THROUGH
WESTERN AND CENTRAL WYOMING THROUGH THE NIGHT.  THE SNOW INTENSITIES
WILL DECREASE WITH THE PASSING OF THE COLD FRONT IN THE WESTERN
M0MOUNTAINS.  MOST AREAS EXPERIENCING HIGH WINDS TODAY WILL SEE
WINDS DECREASE AS THEY SHIFT TO THE NORTHWEST. HIGH WIND WATCHES
REMAIN FOR NORTHERN JOHNSON AND THE WIND RIVER BASIN WITH THE
NORTHWEST WINDS AS THESE AREAS FAVOR HIGH WINDS WITH NORTHWEST
WINDS AND COLD AIR ADVECTION. AREAS EAST OF THE CONTINENTAL DIVIDE
CAN EXPECT A QUICK BURST OF SNOWFALL BEHIND THE COLD FRONT WITH
LIGHT ACCUMULATIONS. OVERALL SNOWFALL WILL BE TAPERING OFF
THROUGH THE MORNING WITH SOME LINGERING MOUNTAIN SNOW SHOWERS ON
SUNDAY. TEMPERATURES WILL COOL ABOUT TEN DEGREES FROM TODAY.

LONG TERM...SUNDAY NIGHT THROUGH SATURDAY

BEHIND THE MAIN SHORTWAVE THAT WILL BE SWINGING THROUGH THIS
WEEKEND...A SECONDARY PIECE OF ENERGY WILL BE SLIDING DOWN THE BACK
SIDE OF THE MAIN TROUGH AXIS ACROSS THE CWA FAIRLY QUICKLY AROUND
12Z MONDAY. WITH WEAK ISENTROPIC LIFT IN THE WEST AHEAD OF THIS
SYSTEM AS WELL AS SOME WEAK QG FORCING IN THE SOUTHWEST...KEPT IDEA
OF ANOTHER 3 TO 6 INCHES OF SNOWFALL IN THE WESTERN MTNS SUNDAY INTO
MONDAY ALONG WITH ANOTHER 2 TO 3 INCHES IN THE WESTERN VALLEYS. THE
SNOW INTENSITY WILL BEGIN TO DECREASE MONDAY AFTERNOON. DURING THE
TROUGH PASSAGE...AROUND 12Z MONDAY...THERE WILL BE A BRIEF PERIOD WHEN THE
SNOWFALL SPILLS OVER TO AREAS EAST OF THE DIVIDE WITH THE MOST
SIGNIFICANT SNOWFALL OCCURRING IN THE BIG HORN MTNS WHERE 3 TO 5
INCHES ARE EXPECTED. THE SNOWFALL WILL DECREASE EAST OF THE DIVIDE
IN THE AFTERNOON AS WELL.

THE NEXT ANTICIPATED SNOW EVENT WILL OCCUR WHEN THE JET STREAM
SHIFTS NORTHEAST PLACING THE FASTER NORTHWEST FLOW ALOFT OVER
WYOMING BY 12Z TUESDAY. THIS WILL DRAW IN ADDITIONAL PACIFIC
MOISTURE FROM THE NORTHWEST ALONG WITH ISENTROPIC LIFT OVER WESTERN
WY TUESDAY WITH AN EXTENSIVE AREA OF ISENTROPIC LIFT SHIFTING TO OUR
NORTH OVER MONTANA BY TUESDAY NIGHT. THIS WILL JUSTIFY LIKELY POPS
IN THE WESTERN/BIG HORN MTNS AS WELL AS CHC POPS OVER THE NORTH HALF
OF THE LOWER ELEVATIONS OF THE CWA TUE/TUE NIGHT. THE JET STREAM
WILL THEN SHIFT NORTHEAST OF THE CWA BY WEDNESDAY.

AFTER THIS TIME FRAME...THE MODELS DIVERGE ONCE AGAIN WITH THE EURO
NOW THE MORE OPTIMISTIC MODEL PLACING A RIDGE OVER WY BY THURSDAY
AND THE GFS KEEPING THE DIRTY NORTHWEST FLOW OVER US THROUGH FRIDAY
WHICH IS IRONIC BECAUSE A COUPLE OF DAYS AGO BOTH THESE MODELS
PORTRAYED OPPOSITE SOLNS WITH THE GFS ADVERTISING A BUILDING RIDGE
AND THE EURO A POTENTIAL SNOW EVENT FOR THANKSGIVING. WITH THE
MODELS FLIP FLOPPING AND NO RUN TO RUN CONSISTENCY...ALL WE ARE
GOING TO DO IS INCREASE THE POPS A TAD OVER MAINLY NW WY FOR THE
SECOND HALF OF NEXT WEEK JUST IN CASE A SNOW EVENT DOES TAKE PLACE
DURING THIS TIME FRAME. MORE SPECIFICALLY...THE GFS PULLS IN COLDER
AIR FROM THE NORTHEAST OVER WY WITH MOST OF THE ASCT ISENTROPIC LIFT
FROM THIS ASCT WEATHER DISTURBANCE REMAINING TO OUR NORTH UP IN MT.

BY FRIDAY NIGHT...THE NW FLOW WILL BACK TO THE WEST AS THE RIDGE
FLATTENS. A MINOR DISTURBANCE MOVING THROUGH THE FLATTENING RIDGE
WITH ITS SHARE OF ISENTROPIC LIFT COULD BRING SOME LIGHT SNOW TO THE
FAR WEST SATURDAY.

TEMPERATURES NEXT WEEK WILL DEPEND LARGELY UPON WHETHER THE GFS OR
THE EURO PANS OUT SO KIND OF WENT WITH A BLEND. IN ANY EVENT...TEMPS
WILL BE MUCH MILDER THAN THEY HAVE BEEN DURING THE LAST COUPLE OF
WEEKS GIVEN THE LACK OF ANY ARCTIC INTRUSIONS NEXT WEEK.

AVIATION.../06Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES
VFR CONDITIONS WILL PREVAIL THROUGH MID-MORNING SUNDAY BEHIND A COLD
FRONT THAT MOVED THROUGH THE AREA SATURDAY EVENING.  AN UPPER LEVEL
DISTURBANCE WILL SPREAD SHSN INTO THE BIGHORN RANGE...FRQT MTN
OBSCURATIONS BY 18Z SUNDAY WITH ISOLD TO WIDELY SCT MVFR -SHSN
MAINLY VCNTY AND EAST OF A KCOD-KWRL-KCPR LINE.  NW SFC WINDS WILL
INCREASE WITH THIS SYSTEM MID TO LATE SUNDAY MORNING WITH WIND GUSTS
OVER 50KTS EXPECTED ALONG AND NORTH OF THE I90 CORRIDOR.  FURTHER
WEST...SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL OCCUR
ACROSS THE WIND RIVER BASIN...VCNTY KRIW.  WINDS WILL DECREASE BUT
REMAIN GUSTY IN THESE AREAS SUNDAY NIGHT.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES
A WEAK UPPER LEVEL DISTURBANCE WILL SLIDE ACROSS W-SW WYOMING EARLY
THIS MORNING SPREADING AREAS OF MVFR/IFR -SN AND MTN OBSCURATIONS
INTO VCNTY KJAC-KAFO THROUGH AROUND 13Z.  A BAND OF MVFR/IFR SNOW IS
ALSO LIKELY TO MOVE EAST ALONG THE INTERSTATE 80 CORRIDOR...VCNTY
KRKS 10Z-15Z.  A DRIER AIRMASS WILL FOLLOW LATE SUNDAY MORNING AND
SUNDAY AFTERNOON WITH SOME LINGERING SNOW SHOWERS OBSCURING MTNS.
GUSTY NW SFC WINDS AT 20-30KTS WILL ALSO DEVELOP BEHIND THIS SYSTEM
DURING THE DAY SUNDAY ACROSS THE UPPER GREEN RIVER BASIN AND ALONG
THE INTERSTATE 80 CORRIDOR.  A MOIST WESTERLY FLOW WILL SPREAD AREAS
OF MVFR/IFR -SN BACK INTO THE WEST...MAINLY VCNTY AND NORTH OF A
KEMM-KPNA LINE SUNDAY NIGHT.

FIRE WEATHER...

SNOWFALL WILL CONTINUE MOST MOUNTAIN AREAS TONIGHT AND THEN
DECREASE THROUGH SUNDAY AS A COLD FRONT PASSES THROUGH.  STRONG WINDS
WILL CONTINUE EARLY THIS EVENING AND THEN DIMINISH. BEHIND THE
COLD FRONT EARLY SUNDAY...HIGH WINDS MAY DEVELOP IN THE WIND
RIVER BASIN AND NORTHERN JOHNSON COUNTIES AS THESE AREAS FAVOR
STRONGER WINDS IN NORTHWEST FLOW. TEMPERATURES WILL BE COLDER WITH
HIGHER HUMIDITY AND LOW MIXING HEIGHTS WITH POOR SMOKE DISPERSAL.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 6 AM MST SUNDAY WYZ012-013-023-024.

HIGH WIND WARNING FROM 5 AM TO 5 PM MST SUNDAY WYZ010.

&&

$$

UPDATE...AEM
SHORT TERM...C.BAKER
LONG TERM...LIPSON
AVIATION...C.BAKER
FIRE WEATHER...C.BAKER








000
FXUS65 KRIW 230636
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1134 PM MST SAT NOV 22 2014

.UPDATE...UPDATED TO ADD 06Z AVIATION DISCUSSION.

.UPDATE...SNOW HAS TAPERED OFF OR ENDED BEHIND A COLD FRONT ACROSS
MOST OF WESTERN WYOMING. ANOTHER SHORTWAVE MOVING EAST ACROSS
IDAHO WILL BRING ANOTHER SHOT OF LIGHT TO MODERATE SNOW INTO FAR
WEST WYOMING AFTER MIDNIGHT. CANCELLED WINTER HIGHLIGHTS FOR ALL
AREAS BUT JACKSON HOLE VALLEY...STAR VALLEY AND SURROUNDING
MOUNTAINS WHERE WINTER STORM WARNINGS REMAIN IN EFFECT UNTIL 6 AM
SUNDAY. COLD FRONT HAS ALSO ENDED THE HIGH WIND THREAT ACROSS
CENTRAL WYOMING...SO HIGH WIND WARNINGS WERE CANCELLED. UPGRADED
HIGH WIND WATCH TO A WARNING FOR ONLY NORTHEAST JOHNSON COUNTY ON
SUNDAY. LATEST MODEL RUNS NOT AS BULLISH WITH STRONG WINDS FURTHER
WEST ACROSS THE WIND RIVER BASIN.

&&

.PREV DISCUSSION... /ISSUED 210 PM MST SAT NOV 22 2014/

SHORT TERM...TONIGHT THROUGH SUNDAY

A PACIFIC COLD FRONT APPROACHING WESTERN WYOMING WILL MOVE THROUGH
WESTERN AND CENTRAL WYOMING THROUGH THE NIGHT.  THE SNOW INTENSITIES
WILL DECREASE WITH THE PASSING OF THE COLD FRONT IN THE WESTERN
M0MOUNTAINS.  MOST AREAS EXPERIENCING HIGH WINDS TODAY WILL SEE
WINDS DECREASE AS THEY SHIFT TO THE NORTHWEST. HIGH WIND WATCHES
REMAIN FOR NORTHERN JOHNSON AND THE WIND RIVER BASIN WITH THE
NORTHWEST WINDS AS THESE AREAS FAVOR HIGH WINDS WITH NORTHWEST
WINDS AND COLD AIR ADVECTION. AREAS EAST OF THE CONTINENTAL DIVIDE
CAN EXPECT A QUICK BURST OF SNOWFALL BEHIND THE COLD FRONT WITH
LIGHT ACCUMULATIONS. OVERALL SNOWFALL WILL BE TAPERING OFF
THROUGH THE MORNING WITH SOME LINGERING MOUNTAIN SNOW SHOWERS ON
SUNDAY. TEMPERATURES WILL COOL ABOUT TEN DEGREES FROM TODAY.

LONG TERM...SUNDAY NIGHT THROUGH SATURDAY

BEHIND THE MAIN SHORTWAVE THAT WILL BE SWINGING THROUGH THIS
WEEKEND...A SECONDARY PIECE OF ENERGY WILL BE SLIDING DOWN THE BACK
SIDE OF THE MAIN TROUGH AXIS ACROSS THE CWA FAIRLY QUICKLY AROUND
12Z MONDAY. WITH WEAK ISENTROPIC LIFT IN THE WEST AHEAD OF THIS
SYSTEM AS WELL AS SOME WEAK QG FORCING IN THE SOUTHWEST...KEPT IDEA
OF ANOTHER 3 TO 6 INCHES OF SNOWFALL IN THE WESTERN MTNS SUNDAY INTO
MONDAY ALONG WITH ANOTHER 2 TO 3 INCHES IN THE WESTERN VALLEYS. THE
SNOW INTENSITY WILL BEGIN TO DECREASE MONDAY AFTERNOON. DURING THE
TROUGH PASSAGE...AROUND 12Z MONDAY...THERE WILL BE A BRIEF PERIOD WHEN THE
SNOWFALL SPILLS OVER TO AREAS EAST OF THE DIVIDE WITH THE MOST
SIGNIFICANT SNOWFALL OCCURRING IN THE BIG HORN MTNS WHERE 3 TO 5
INCHES ARE EXPECTED. THE SNOWFALL WILL DECREASE EAST OF THE DIVIDE
IN THE AFTERNOON AS WELL.

THE NEXT ANTICIPATED SNOW EVENT WILL OCCUR WHEN THE JET STREAM
SHIFTS NORTHEAST PLACING THE FASTER NORTHWEST FLOW ALOFT OVER
WYOMING BY 12Z TUESDAY. THIS WILL DRAW IN ADDITIONAL PACIFIC
MOISTURE FROM THE NORTHWEST ALONG WITH ISENTROPIC LIFT OVER WESTERN
WY TUESDAY WITH AN EXTENSIVE AREA OF ISENTROPIC LIFT SHIFTING TO OUR
NORTH OVER MONTANA BY TUESDAY NIGHT. THIS WILL JUSTIFY LIKELY POPS
IN THE WESTERN/BIG HORN MTNS AS WELL AS CHC POPS OVER THE NORTH HALF
OF THE LOWER ELEVATIONS OF THE CWA TUE/TUE NIGHT. THE JET STREAM
WILL THEN SHIFT NORTHEAST OF THE CWA BY WEDNESDAY.

AFTER THIS TIME FRAME...THE MODELS DIVERGE ONCE AGAIN WITH THE EURO
NOW THE MORE OPTIMISTIC MODEL PLACING A RIDGE OVER WY BY THURSDAY
AND THE GFS KEEPING THE DIRTY NORTHWEST FLOW OVER US THROUGH FRIDAY
WHICH IS IRONIC BECAUSE A COUPLE OF DAYS AGO BOTH THESE MODELS
PORTRAYED OPPOSITE SOLNS WITH THE GFS ADVERTISING A BUILDING RIDGE
AND THE EURO A POTENTIAL SNOW EVENT FOR THANKSGIVING. WITH THE
MODELS FLIP FLOPPING AND NO RUN TO RUN CONSISTENCY...ALL WE ARE
GOING TO DO IS INCREASE THE POPS A TAD OVER MAINLY NW WY FOR THE
SECOND HALF OF NEXT WEEK JUST IN CASE A SNOW EVENT DOES TAKE PLACE
DURING THIS TIME FRAME. MORE SPECIFICALLY...THE GFS PULLS IN COLDER
AIR FROM THE NORTHEAST OVER WY WITH MOST OF THE ASCT ISENTROPIC LIFT
FROM THIS ASCT WEATHER DISTURBANCE REMAINING TO OUR NORTH UP IN MT.

BY FRIDAY NIGHT...THE NW FLOW WILL BACK TO THE WEST AS THE RIDGE
FLATTENS. A MINOR DISTURBANCE MOVING THROUGH THE FLATTENING RIDGE
WITH ITS SHARE OF ISENTROPIC LIFT COULD BRING SOME LIGHT SNOW TO THE
FAR WEST SATURDAY.

TEMPERATURES NEXT WEEK WILL DEPEND LARGELY UPON WHETHER THE GFS OR
THE EURO PANS OUT SO KIND OF WENT WITH A BLEND. IN ANY EVENT...TEMPS
WILL BE MUCH MILDER THAN THEY HAVE BEEN DURING THE LAST COUPLE OF
WEEKS GIVEN THE LACK OF ANY ARCTIC INTRUSIONS NEXT WEEK.

AVIATION.../06Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES
VFR CONDITIONS WILL PREVAIL THROUGH MID-MORNING SUNDAY BEHIND A COLD
FRONT THAT MOVED THROUGH THE AREA SATURDAY EVENING.  AN UPPER LEVEL
DISTURBANCE WILL SPREAD SHSN INTO THE BIGHORN RANGE...FRQT MTN
OBSCURATIONS BY 18Z SUNDAY WITH ISOLD TO WIDELY SCT MVFR -SHSN
MAINLY VCNTY AND EAST OF A KCOD-KWRL-KCPR LINE.  NW SFC WINDS WILL
INCREASE WITH THIS SYSTEM MID TO LATE SUNDAY MORNING WITH WIND GUSTS
OVER 50KTS EXPECTED ALONG AND NORTH OF THE I90 CORRIDOR.  FURTHER
WEST...SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL OCCUR
ACROSS THE WIND RIVER BASIN...VCNTY KRIW.  WINDS WILL DECREASE BUT
REMAIN GUSTY IN THESE AREAS SUNDAY NIGHT.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES
A WEAK UPPER LEVEL DISTURBANCE WILL SLIDE ACROSS W-SW WYOMING EARLY
THIS MORNING SPREADING AREAS OF MVFR/IFR -SN AND MTN OBSCURATIONS
INTO VCNTY KJAC-KAFO THROUGH AROUND 13Z.  A BAND OF MVFR/IFR SNOW IS
ALSO LIKELY TO MOVE EAST ALONG THE INTERSTATE 80 CORRIDOR...VCNTY
KRKS 10Z-15Z.  A DRIER AIRMASS WILL FOLLOW LATE SUNDAY MORNING AND
SUNDAY AFTERNOON WITH SOME LINGERING SNOW SHOWERS OBSCURING MTNS.
GUSTY NW SFC WINDS AT 20-30KTS WILL ALSO DEVELOP BEHIND THIS SYSTEM
DURING THE DAY SUNDAY ACROSS THE UPPER GREEN RIVER BASIN AND ALONG
THE INTERSTATE 80 CORRIDOR.  A MOIST WESTERLY FLOW WILL SPREAD AREAS
OF MVFR/IFR -SN BACK INTO THE WEST...MAINLY VCNTY AND NORTH OF A
KEMM-KPNA LINE SUNDAY NIGHT.

FIRE WEATHER...

SNOWFALL WILL CONTINUE MOST MOUNTAIN AREAS TONIGHT AND THEN
DECREASE THROUGH SUNDAY AS A COLD FRONT PASSES THROUGH.  STRONG WINDS
WILL CONTINUE EARLY THIS EVENING AND THEN DIMINISH. BEHIND THE
COLD FRONT EARLY SUNDAY...HIGH WINDS MAY DEVELOP IN THE WIND
RIVER BASIN AND NORTHERN JOHNSON COUNTIES AS THESE AREAS FAVOR
STRONGER WINDS IN NORTHWEST FLOW. TEMPERATURES WILL BE COLDER WITH
HIGHER HUMIDITY AND LOW MIXING HEIGHTS WITH POOR SMOKE DISPERSAL.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 6 AM MST SUNDAY WYZ012-013-023-024.

HIGH WIND WARNING FROM 5 AM TO 5 PM MST SUNDAY WYZ010.

&&

$$

UPDATE...AEM
SHORT TERM...C.BAKER
LONG TERM...LIPSON
AVIATION...C.BAKER
FIRE WEATHER...C.BAKER








000
FXUS65 KRIW 230636
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1134 PM MST SAT NOV 22 2014

.UPDATE...UPDATED TO ADD 06Z AVIATION DISCUSSION.

.UPDATE...SNOW HAS TAPERED OFF OR ENDED BEHIND A COLD FRONT ACROSS
MOST OF WESTERN WYOMING. ANOTHER SHORTWAVE MOVING EAST ACROSS
IDAHO WILL BRING ANOTHER SHOT OF LIGHT TO MODERATE SNOW INTO FAR
WEST WYOMING AFTER MIDNIGHT. CANCELLED WINTER HIGHLIGHTS FOR ALL
AREAS BUT JACKSON HOLE VALLEY...STAR VALLEY AND SURROUNDING
MOUNTAINS WHERE WINTER STORM WARNINGS REMAIN IN EFFECT UNTIL 6 AM
SUNDAY. COLD FRONT HAS ALSO ENDED THE HIGH WIND THREAT ACROSS
CENTRAL WYOMING...SO HIGH WIND WARNINGS WERE CANCELLED. UPGRADED
HIGH WIND WATCH TO A WARNING FOR ONLY NORTHEAST JOHNSON COUNTY ON
SUNDAY. LATEST MODEL RUNS NOT AS BULLISH WITH STRONG WINDS FURTHER
WEST ACROSS THE WIND RIVER BASIN.

&&

.PREV DISCUSSION... /ISSUED 210 PM MST SAT NOV 22 2014/

SHORT TERM...TONIGHT THROUGH SUNDAY

A PACIFIC COLD FRONT APPROACHING WESTERN WYOMING WILL MOVE THROUGH
WESTERN AND CENTRAL WYOMING THROUGH THE NIGHT.  THE SNOW INTENSITIES
WILL DECREASE WITH THE PASSING OF THE COLD FRONT IN THE WESTERN
M0MOUNTAINS.  MOST AREAS EXPERIENCING HIGH WINDS TODAY WILL SEE
WINDS DECREASE AS THEY SHIFT TO THE NORTHWEST. HIGH WIND WATCHES
REMAIN FOR NORTHERN JOHNSON AND THE WIND RIVER BASIN WITH THE
NORTHWEST WINDS AS THESE AREAS FAVOR HIGH WINDS WITH NORTHWEST
WINDS AND COLD AIR ADVECTION. AREAS EAST OF THE CONTINENTAL DIVIDE
CAN EXPECT A QUICK BURST OF SNOWFALL BEHIND THE COLD FRONT WITH
LIGHT ACCUMULATIONS. OVERALL SNOWFALL WILL BE TAPERING OFF
THROUGH THE MORNING WITH SOME LINGERING MOUNTAIN SNOW SHOWERS ON
SUNDAY. TEMPERATURES WILL COOL ABOUT TEN DEGREES FROM TODAY.

LONG TERM...SUNDAY NIGHT THROUGH SATURDAY

BEHIND THE MAIN SHORTWAVE THAT WILL BE SWINGING THROUGH THIS
WEEKEND...A SECONDARY PIECE OF ENERGY WILL BE SLIDING DOWN THE BACK
SIDE OF THE MAIN TROUGH AXIS ACROSS THE CWA FAIRLY QUICKLY AROUND
12Z MONDAY. WITH WEAK ISENTROPIC LIFT IN THE WEST AHEAD OF THIS
SYSTEM AS WELL AS SOME WEAK QG FORCING IN THE SOUTHWEST...KEPT IDEA
OF ANOTHER 3 TO 6 INCHES OF SNOWFALL IN THE WESTERN MTNS SUNDAY INTO
MONDAY ALONG WITH ANOTHER 2 TO 3 INCHES IN THE WESTERN VALLEYS. THE
SNOW INTENSITY WILL BEGIN TO DECREASE MONDAY AFTERNOON. DURING THE
TROUGH PASSAGE...AROUND 12Z MONDAY...THERE WILL BE A BRIEF PERIOD WHEN THE
SNOWFALL SPILLS OVER TO AREAS EAST OF THE DIVIDE WITH THE MOST
SIGNIFICANT SNOWFALL OCCURRING IN THE BIG HORN MTNS WHERE 3 TO 5
INCHES ARE EXPECTED. THE SNOWFALL WILL DECREASE EAST OF THE DIVIDE
IN THE AFTERNOON AS WELL.

THE NEXT ANTICIPATED SNOW EVENT WILL OCCUR WHEN THE JET STREAM
SHIFTS NORTHEAST PLACING THE FASTER NORTHWEST FLOW ALOFT OVER
WYOMING BY 12Z TUESDAY. THIS WILL DRAW IN ADDITIONAL PACIFIC
MOISTURE FROM THE NORTHWEST ALONG WITH ISENTROPIC LIFT OVER WESTERN
WY TUESDAY WITH AN EXTENSIVE AREA OF ISENTROPIC LIFT SHIFTING TO OUR
NORTH OVER MONTANA BY TUESDAY NIGHT. THIS WILL JUSTIFY LIKELY POPS
IN THE WESTERN/BIG HORN MTNS AS WELL AS CHC POPS OVER THE NORTH HALF
OF THE LOWER ELEVATIONS OF THE CWA TUE/TUE NIGHT. THE JET STREAM
WILL THEN SHIFT NORTHEAST OF THE CWA BY WEDNESDAY.

AFTER THIS TIME FRAME...THE MODELS DIVERGE ONCE AGAIN WITH THE EURO
NOW THE MORE OPTIMISTIC MODEL PLACING A RIDGE OVER WY BY THURSDAY
AND THE GFS KEEPING THE DIRTY NORTHWEST FLOW OVER US THROUGH FRIDAY
WHICH IS IRONIC BECAUSE A COUPLE OF DAYS AGO BOTH THESE MODELS
PORTRAYED OPPOSITE SOLNS WITH THE GFS ADVERTISING A BUILDING RIDGE
AND THE EURO A POTENTIAL SNOW EVENT FOR THANKSGIVING. WITH THE
MODELS FLIP FLOPPING AND NO RUN TO RUN CONSISTENCY...ALL WE ARE
GOING TO DO IS INCREASE THE POPS A TAD OVER MAINLY NW WY FOR THE
SECOND HALF OF NEXT WEEK JUST IN CASE A SNOW EVENT DOES TAKE PLACE
DURING THIS TIME FRAME. MORE SPECIFICALLY...THE GFS PULLS IN COLDER
AIR FROM THE NORTHEAST OVER WY WITH MOST OF THE ASCT ISENTROPIC LIFT
FROM THIS ASCT WEATHER DISTURBANCE REMAINING TO OUR NORTH UP IN MT.

BY FRIDAY NIGHT...THE NW FLOW WILL BACK TO THE WEST AS THE RIDGE
FLATTENS. A MINOR DISTURBANCE MOVING THROUGH THE FLATTENING RIDGE
WITH ITS SHARE OF ISENTROPIC LIFT COULD BRING SOME LIGHT SNOW TO THE
FAR WEST SATURDAY.

TEMPERATURES NEXT WEEK WILL DEPEND LARGELY UPON WHETHER THE GFS OR
THE EURO PANS OUT SO KIND OF WENT WITH A BLEND. IN ANY EVENT...TEMPS
WILL BE MUCH MILDER THAN THEY HAVE BEEN DURING THE LAST COUPLE OF
WEEKS GIVEN THE LACK OF ANY ARCTIC INTRUSIONS NEXT WEEK.

AVIATION.../06Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES
VFR CONDITIONS WILL PREVAIL THROUGH MID-MORNING SUNDAY BEHIND A COLD
FRONT THAT MOVED THROUGH THE AREA SATURDAY EVENING.  AN UPPER LEVEL
DISTURBANCE WILL SPREAD SHSN INTO THE BIGHORN RANGE...FRQT MTN
OBSCURATIONS BY 18Z SUNDAY WITH ISOLD TO WIDELY SCT MVFR -SHSN
MAINLY VCNTY AND EAST OF A KCOD-KWRL-KCPR LINE.  NW SFC WINDS WILL
INCREASE WITH THIS SYSTEM MID TO LATE SUNDAY MORNING WITH WIND GUSTS
OVER 50KTS EXPECTED ALONG AND NORTH OF THE I90 CORRIDOR.  FURTHER
WEST...SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL OCCUR
ACROSS THE WIND RIVER BASIN...VCNTY KRIW.  WINDS WILL DECREASE BUT
REMAIN GUSTY IN THESE AREAS SUNDAY NIGHT.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES
A WEAK UPPER LEVEL DISTURBANCE WILL SLIDE ACROSS W-SW WYOMING EARLY
THIS MORNING SPREADING AREAS OF MVFR/IFR -SN AND MTN OBSCURATIONS
INTO VCNTY KJAC-KAFO THROUGH AROUND 13Z.  A BAND OF MVFR/IFR SNOW IS
ALSO LIKELY TO MOVE EAST ALONG THE INTERSTATE 80 CORRIDOR...VCNTY
KRKS 10Z-15Z.  A DRIER AIRMASS WILL FOLLOW LATE SUNDAY MORNING AND
SUNDAY AFTERNOON WITH SOME LINGERING SNOW SHOWERS OBSCURING MTNS.
GUSTY NW SFC WINDS AT 20-30KTS WILL ALSO DEVELOP BEHIND THIS SYSTEM
DURING THE DAY SUNDAY ACROSS THE UPPER GREEN RIVER BASIN AND ALONG
THE INTERSTATE 80 CORRIDOR.  A MOIST WESTERLY FLOW WILL SPREAD AREAS
OF MVFR/IFR -SN BACK INTO THE WEST...MAINLY VCNTY AND NORTH OF A
KEMM-KPNA LINE SUNDAY NIGHT.

FIRE WEATHER...

SNOWFALL WILL CONTINUE MOST MOUNTAIN AREAS TONIGHT AND THEN
DECREASE THROUGH SUNDAY AS A COLD FRONT PASSES THROUGH.  STRONG WINDS
WILL CONTINUE EARLY THIS EVENING AND THEN DIMINISH. BEHIND THE
COLD FRONT EARLY SUNDAY...HIGH WINDS MAY DEVELOP IN THE WIND
RIVER BASIN AND NORTHERN JOHNSON COUNTIES AS THESE AREAS FAVOR
STRONGER WINDS IN NORTHWEST FLOW. TEMPERATURES WILL BE COLDER WITH
HIGHER HUMIDITY AND LOW MIXING HEIGHTS WITH POOR SMOKE DISPERSAL.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 6 AM MST SUNDAY WYZ012-013-023-024.

HIGH WIND WARNING FROM 5 AM TO 5 PM MST SUNDAY WYZ010.

&&

$$

UPDATE...AEM
SHORT TERM...C.BAKER
LONG TERM...LIPSON
AVIATION...C.BAKER
FIRE WEATHER...C.BAKER








000
FXUS65 KRIW 230636
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1134 PM MST SAT NOV 22 2014

.UPDATE...UPDATED TO ADD 06Z AVIATION DISCUSSION.

.UPDATE...SNOW HAS TAPERED OFF OR ENDED BEHIND A COLD FRONT ACROSS
MOST OF WESTERN WYOMING. ANOTHER SHORTWAVE MOVING EAST ACROSS
IDAHO WILL BRING ANOTHER SHOT OF LIGHT TO MODERATE SNOW INTO FAR
WEST WYOMING AFTER MIDNIGHT. CANCELLED WINTER HIGHLIGHTS FOR ALL
AREAS BUT JACKSON HOLE VALLEY...STAR VALLEY AND SURROUNDING
MOUNTAINS WHERE WINTER STORM WARNINGS REMAIN IN EFFECT UNTIL 6 AM
SUNDAY. COLD FRONT HAS ALSO ENDED THE HIGH WIND THREAT ACROSS
CENTRAL WYOMING...SO HIGH WIND WARNINGS WERE CANCELLED. UPGRADED
HIGH WIND WATCH TO A WARNING FOR ONLY NORTHEAST JOHNSON COUNTY ON
SUNDAY. LATEST MODEL RUNS NOT AS BULLISH WITH STRONG WINDS FURTHER
WEST ACROSS THE WIND RIVER BASIN.

&&

.PREV DISCUSSION... /ISSUED 210 PM MST SAT NOV 22 2014/

SHORT TERM...TONIGHT THROUGH SUNDAY

A PACIFIC COLD FRONT APPROACHING WESTERN WYOMING WILL MOVE THROUGH
WESTERN AND CENTRAL WYOMING THROUGH THE NIGHT.  THE SNOW INTENSITIES
WILL DECREASE WITH THE PASSING OF THE COLD FRONT IN THE WESTERN
M0MOUNTAINS.  MOST AREAS EXPERIENCING HIGH WINDS TODAY WILL SEE
WINDS DECREASE AS THEY SHIFT TO THE NORTHWEST. HIGH WIND WATCHES
REMAIN FOR NORTHERN JOHNSON AND THE WIND RIVER BASIN WITH THE
NORTHWEST WINDS AS THESE AREAS FAVOR HIGH WINDS WITH NORTHWEST
WINDS AND COLD AIR ADVECTION. AREAS EAST OF THE CONTINENTAL DIVIDE
CAN EXPECT A QUICK BURST OF SNOWFALL BEHIND THE COLD FRONT WITH
LIGHT ACCUMULATIONS. OVERALL SNOWFALL WILL BE TAPERING OFF
THROUGH THE MORNING WITH SOME LINGERING MOUNTAIN SNOW SHOWERS ON
SUNDAY. TEMPERATURES WILL COOL ABOUT TEN DEGREES FROM TODAY.

LONG TERM...SUNDAY NIGHT THROUGH SATURDAY

BEHIND THE MAIN SHORTWAVE THAT WILL BE SWINGING THROUGH THIS
WEEKEND...A SECONDARY PIECE OF ENERGY WILL BE SLIDING DOWN THE BACK
SIDE OF THE MAIN TROUGH AXIS ACROSS THE CWA FAIRLY QUICKLY AROUND
12Z MONDAY. WITH WEAK ISENTROPIC LIFT IN THE WEST AHEAD OF THIS
SYSTEM AS WELL AS SOME WEAK QG FORCING IN THE SOUTHWEST...KEPT IDEA
OF ANOTHER 3 TO 6 INCHES OF SNOWFALL IN THE WESTERN MTNS SUNDAY INTO
MONDAY ALONG WITH ANOTHER 2 TO 3 INCHES IN THE WESTERN VALLEYS. THE
SNOW INTENSITY WILL BEGIN TO DECREASE MONDAY AFTERNOON. DURING THE
TROUGH PASSAGE...AROUND 12Z MONDAY...THERE WILL BE A BRIEF PERIOD WHEN THE
SNOWFALL SPILLS OVER TO AREAS EAST OF THE DIVIDE WITH THE MOST
SIGNIFICANT SNOWFALL OCCURRING IN THE BIG HORN MTNS WHERE 3 TO 5
INCHES ARE EXPECTED. THE SNOWFALL WILL DECREASE EAST OF THE DIVIDE
IN THE AFTERNOON AS WELL.

THE NEXT ANTICIPATED SNOW EVENT WILL OCCUR WHEN THE JET STREAM
SHIFTS NORTHEAST PLACING THE FASTER NORTHWEST FLOW ALOFT OVER
WYOMING BY 12Z TUESDAY. THIS WILL DRAW IN ADDITIONAL PACIFIC
MOISTURE FROM THE NORTHWEST ALONG WITH ISENTROPIC LIFT OVER WESTERN
WY TUESDAY WITH AN EXTENSIVE AREA OF ISENTROPIC LIFT SHIFTING TO OUR
NORTH OVER MONTANA BY TUESDAY NIGHT. THIS WILL JUSTIFY LIKELY POPS
IN THE WESTERN/BIG HORN MTNS AS WELL AS CHC POPS OVER THE NORTH HALF
OF THE LOWER ELEVATIONS OF THE CWA TUE/TUE NIGHT. THE JET STREAM
WILL THEN SHIFT NORTHEAST OF THE CWA BY WEDNESDAY.

AFTER THIS TIME FRAME...THE MODELS DIVERGE ONCE AGAIN WITH THE EURO
NOW THE MORE OPTIMISTIC MODEL PLACING A RIDGE OVER WY BY THURSDAY
AND THE GFS KEEPING THE DIRTY NORTHWEST FLOW OVER US THROUGH FRIDAY
WHICH IS IRONIC BECAUSE A COUPLE OF DAYS AGO BOTH THESE MODELS
PORTRAYED OPPOSITE SOLNS WITH THE GFS ADVERTISING A BUILDING RIDGE
AND THE EURO A POTENTIAL SNOW EVENT FOR THANKSGIVING. WITH THE
MODELS FLIP FLOPPING AND NO RUN TO RUN CONSISTENCY...ALL WE ARE
GOING TO DO IS INCREASE THE POPS A TAD OVER MAINLY NW WY FOR THE
SECOND HALF OF NEXT WEEK JUST IN CASE A SNOW EVENT DOES TAKE PLACE
DURING THIS TIME FRAME. MORE SPECIFICALLY...THE GFS PULLS IN COLDER
AIR FROM THE NORTHEAST OVER WY WITH MOST OF THE ASCT ISENTROPIC LIFT
FROM THIS ASCT WEATHER DISTURBANCE REMAINING TO OUR NORTH UP IN MT.

BY FRIDAY NIGHT...THE NW FLOW WILL BACK TO THE WEST AS THE RIDGE
FLATTENS. A MINOR DISTURBANCE MOVING THROUGH THE FLATTENING RIDGE
WITH ITS SHARE OF ISENTROPIC LIFT COULD BRING SOME LIGHT SNOW TO THE
FAR WEST SATURDAY.

TEMPERATURES NEXT WEEK WILL DEPEND LARGELY UPON WHETHER THE GFS OR
THE EURO PANS OUT SO KIND OF WENT WITH A BLEND. IN ANY EVENT...TEMPS
WILL BE MUCH MILDER THAN THEY HAVE BEEN DURING THE LAST COUPLE OF
WEEKS GIVEN THE LACK OF ANY ARCTIC INTRUSIONS NEXT WEEK.

AVIATION.../06Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES
VFR CONDITIONS WILL PREVAIL THROUGH MID-MORNING SUNDAY BEHIND A COLD
FRONT THAT MOVED THROUGH THE AREA SATURDAY EVENING.  AN UPPER LEVEL
DISTURBANCE WILL SPREAD SHSN INTO THE BIGHORN RANGE...FRQT MTN
OBSCURATIONS BY 18Z SUNDAY WITH ISOLD TO WIDELY SCT MVFR -SHSN
MAINLY VCNTY AND EAST OF A KCOD-KWRL-KCPR LINE.  NW SFC WINDS WILL
INCREASE WITH THIS SYSTEM MID TO LATE SUNDAY MORNING WITH WIND GUSTS
OVER 50KTS EXPECTED ALONG AND NORTH OF THE I90 CORRIDOR.  FURTHER
WEST...SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL OCCUR
ACROSS THE WIND RIVER BASIN...VCNTY KRIW.  WINDS WILL DECREASE BUT
REMAIN GUSTY IN THESE AREAS SUNDAY NIGHT.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES
A WEAK UPPER LEVEL DISTURBANCE WILL SLIDE ACROSS W-SW WYOMING EARLY
THIS MORNING SPREADING AREAS OF MVFR/IFR -SN AND MTN OBSCURATIONS
INTO VCNTY KJAC-KAFO THROUGH AROUND 13Z.  A BAND OF MVFR/IFR SNOW IS
ALSO LIKELY TO MOVE EAST ALONG THE INTERSTATE 80 CORRIDOR...VCNTY
KRKS 10Z-15Z.  A DRIER AIRMASS WILL FOLLOW LATE SUNDAY MORNING AND
SUNDAY AFTERNOON WITH SOME LINGERING SNOW SHOWERS OBSCURING MTNS.
GUSTY NW SFC WINDS AT 20-30KTS WILL ALSO DEVELOP BEHIND THIS SYSTEM
DURING THE DAY SUNDAY ACROSS THE UPPER GREEN RIVER BASIN AND ALONG
THE INTERSTATE 80 CORRIDOR.  A MOIST WESTERLY FLOW WILL SPREAD AREAS
OF MVFR/IFR -SN BACK INTO THE WEST...MAINLY VCNTY AND NORTH OF A
KEMM-KPNA LINE SUNDAY NIGHT.

FIRE WEATHER...

SNOWFALL WILL CONTINUE MOST MOUNTAIN AREAS TONIGHT AND THEN
DECREASE THROUGH SUNDAY AS A COLD FRONT PASSES THROUGH.  STRONG WINDS
WILL CONTINUE EARLY THIS EVENING AND THEN DIMINISH. BEHIND THE
COLD FRONT EARLY SUNDAY...HIGH WINDS MAY DEVELOP IN THE WIND
RIVER BASIN AND NORTHERN JOHNSON COUNTIES AS THESE AREAS FAVOR
STRONGER WINDS IN NORTHWEST FLOW. TEMPERATURES WILL BE COLDER WITH
HIGHER HUMIDITY AND LOW MIXING HEIGHTS WITH POOR SMOKE DISPERSAL.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 6 AM MST SUNDAY WYZ012-013-023-024.

HIGH WIND WARNING FROM 5 AM TO 5 PM MST SUNDAY WYZ010.

&&

$$

UPDATE...AEM
SHORT TERM...C.BAKER
LONG TERM...LIPSON
AVIATION...C.BAKER
FIRE WEATHER...C.BAKER







  [top]

000
FXUS65 KCYS 230544
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1044 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 932 PM MST SAT NOV 22 2014

WINDS PER SURFACE/HIGHWAY OBSERVATIONS THE PAST FEW HOURS HAVE
SHOWN A GRADUAL DECREASING TREND...AND THE THREAT FOR HIGH WINDS
TONIGHT HAS ENDED. THUS HAVE CANCELLED HIGH WIND WARNINGS. COLD
FRONT HAS MOVED THROUGH RIVERTON AND CASPER AND WILL CONTINUE ITS
STEADY SOUTHEASTWARD PROGRESS THROUGH THE CWA TONIGHT. GUSTY
NORTHWEST WINDS OF 35 TO 45 MPH WILL OCCUR BEHIND THE FRONT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM MST SAT NOV 22 2014

PRIMARY CONCERNS THROUGH THIS WEEKEND WILL BE WINDS AND MOUNTAIN
SNOWFALL. MOST OF THE AREA WITHIN THE HIGH WIND WARNING HAS
VERIFIED THIS AFTERNOON WITH GUSTS AS HIGH AS 76 MPH REPORTED
ALONG I25 AND I80. ELSEWHERE...WINDS HAVE STRUGGLED ACROSS
LOCATIONS SUCH AS THE LARAMIE VALLEY AND THE HIGH PLAINS
IMMEDIATELY EAST OF THE LARAMIE RANGE. BELIEVE THIS IS DUE TO A
COMBINATION OF CLOUDY SKIES AND AN AREA OF POSITIVE OMEGA EAST OF
THE MOUNTAINS. WILL KEEP THE HIGH WIND WARNING OUT FOR THESE
AREAS...BUT THERE IS ONLY A SMALL WINDOW TO SEE GUSTS AROUND 55
MPH SINCE DOWNSLOPE AND SUBSIDENCE WILL BEGIN TO DIMINISH BY LATE
THIS EVENING. ENDED THE HIGH WIND WARNING AT MIDNIGHT TONIGHT
SINCE THE FRONT AND IS TRENDING A BIT FASTER AND SHOULD BE NEAR
THE COLORADO BORDER A FEW HOURS BEFORE MIDNIGHT. AFTER THE FRONT
AND ASSOCIATED TROUGH AXIS ALOFT MOVES THROUGH...WINDS WILL SHIFT
INTO THE NORTHWEST WHICH WILL END THE HIGH WIND EVENT BRIEFLY FOR
THE WIND PRONE AREAS AS WELL. HOWEVER...HIGH WINDS WILL LIKELY
RETURN BY LATE MONDAY NIGHT ACROSS MOST OF SOUTHEAST WYOMING.

SNOW WILL BE ANOTHER CONCERN...PRIMARILY ACROSS THE MOUNTAINS OF
SOUTHEAST WYOMING AND PERHAPS EVEN SOME OF THE HIGH VALLEYS. SNOW
IS DEVELOPING ACROSS THE MOUNTAINS EARLY THIS AFTERNOON WITH SOME
RAIN/SNOW MIX DOWN TO THE VALLEY FLOORS. ANY RAINFALL WILL QUICKLY
CHANGE TO SNOW LATE THIS AFTERNOON AS MUCH COLDER AIR MOVES INTO
THE AREA. THE HEAVIEST SNOW WILL BE TONIGHT...BUT ANOTHER
DISTURBANCE ALOFT WILL PUSH ACROSS THE AREA ON SUNDAY AS WELL
RESULTING IN SOME ENHANCEMENT OF SNOWFALL RATES. HIGH CONFIDENCE
THAT THE MOUNTAINS WILL DO WELL WITH THIS EVENT...SO KEPT THE
WINTER STORM WARNING GOING THROUGH MONDAY FOR 1 TO 2 FEET OF SNOW.
EXPECT THE PRECIPITATION TO BE ENHANCED FURTHER ON THE WEST TO
NORTHWEST FACING SLOPES AND RIDGES DUE TO UPSLOPE FLOW. FOR THE
VALLEYS AND HIGH PLAINS...EXPECT PERHAPS 1 TO 2 INCHES ALONG I80
WEST OF THE LARAMIE RANGE AND FURTHER NORTH ALONG I80 AROUND
DOUGLAS. THE CHEYENNE RIDGE FROM CHEYENNE TO SIDNEY INCLUDING MOST
OF THE NEBRASKA PANHANDLE WILL BE LUCKY TO SEE A DUSTING OF SNOW
DUE TO THE LARGE LOW LEVEL DOWNSLOPE COMPONENT TO THE WINDS. THE
BEST CHANCE TO SEE SOME SNOW WILL BE NEAR THE FRONTAL PASSAGE DUE
TO BRIEF FRONTOGENESIS AND LOW LEVEL DYNAMIC LIFT. THERE IS SOME
CONCERN THAT THE ADJACENT VALLEYS ACROSS SOUTHERN CARBON COUNTY
WILL SEE SOME MODERATE SNOWFALL RATES AS THE WINDS SHIFT INTO THE
NORTHWEST. WILL CONTINUE TO KEEP AN EYE ON THIS THROUGH SUNDAY AS
THE NEXT DISTURBANCE MOVES ACROSS THE AREA. FOR NOW...KEPT 1 TO 3
INCHES OF SNOW IN THESE LOCATIONS WITH 5 INCHES POSSIBLE LOCALLY.

FOR MONDAY...ANOTHER DISTURBANCE ALOFT WILL MOVE ACROSS THE
AREA...RESULTING IN ENHANCED SNOWFALL RATES ACROSS THE MOUNTAINS
AFTER A BRIEF LULL SUNDAY NIGHT. THIS MAY BE THE BEST CHANCE FOR
THE HIGH PLAINS TO RECEIVE SOME WIDESPREAD LIGHT SNOW
ACCUMULATIONS AS WINDS SHIFT INTO THE NORTH.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 300 PM MST SAT NOV 22 2014

STRONG WINDS CONTINUE THROUGH AT LEAST WEDNESDAY. GFS SHOWING A
1041MB SURFACE HIGH OVER WESTERN COLORADO TUESDAY MORNING WITH
A ROUGHLY 10-12MB SURFACE GRADIENT BETWEEN CASPER AND CRAIG.
700MB WINDS FROM THE NORTHWEST AT 50-60KTS WITH A 700MB HEIGHT
GRADIENT AROUND 70 TO 80 MARS BETWEEN CRAIG AND CASPER. ALMOST A
SURE THING FOR WIND WARNING CRITERIA AT LEAST FOR THE WIND PRONE
AREAS AND HAVE BUMPED UP GUIDANCE AT THESE LOCATIONS TO REFLECT
CONFIDENCE IN HIGH WINDS.

WINDS LOOK TO FINALLY EASE SOME THURSDAY AS WE SEE A FRONT DIVE
SOUTHWEST OUT OF THE DAKOTAS AND LAY UP AGAINST THE LARAMIE RANGE.
ECMWF A LITTLE FURTHER NORTHEAST WITH THIS FRONT OVER THE MORE
AGGRESSIVE GFS...FINALLY PUSHING THE BOUNDARY INTO THE LARAMIE
RANGE THURSDAY EVENING. DID GO AHEAD AND LOWER TEMPERATURES SOME
OVER THE NORTHERN PANHANDLE AND OUR EASTERN ZONES TO REFLECT THE
MUCH COLDER AIR BEHIND THE FRONT FOR THURSDAY THROUGH FRIDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1037 PM MST SAT NOV 22 2014

GUSTY WEST TO NORTHWEST WINDS OF 30 TO 40 KT WILL CONTINUE TONIGHT
WITH THE PASSAGE OF A COLD FRONT. OCCASIONAL MVFR CONDITIONS IN
LIGHT SNOW WILL AFFECT MOST TERMINALS TONIGHT THROUGH EARLY SUNDAY
MORNING. MVFR CEILINGS MAY LINGER THROUGH MUCH OF THE DAY SUNDAY
FOR THE RAWLINS/SARATOGA AREAS...WITH THE MOUNTAINS OBSCURED WITH
FALLING/BLOWING SNOW. VFR CONDITIONS SHOULD RESUME LATER SUNDAY
MORNING ELSEWHERE. STRONG AND GUSTY NORTHWEST WINDS WILL PREVAIL
SUNDAY.

&&

.FIRE WEATHER...
ISSUED AT 209 PM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG THROUGH EARLY NEXT WEEK...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED DUE TO COOL TEMPERATURES AND HIGH
RELATIVE HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ112-114.

NE...WIND ADVISORY FROM 9 AM TO 6 PM MST SUNDAY FOR NEZ002-003-
     019>021-054-055-095-096.

&&

$$

UPDATE...MJ
SHORT TERM...TJT
LONG TERM...GCC
AVIATION...MJ
FIRE WEATHER...TJT




000
FXUS65 KCYS 230544
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1044 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 932 PM MST SAT NOV 22 2014

WINDS PER SURFACE/HIGHWAY OBSERVATIONS THE PAST FEW HOURS HAVE
SHOWN A GRADUAL DECREASING TREND...AND THE THREAT FOR HIGH WINDS
TONIGHT HAS ENDED. THUS HAVE CANCELLED HIGH WIND WARNINGS. COLD
FRONT HAS MOVED THROUGH RIVERTON AND CASPER AND WILL CONTINUE ITS
STEADY SOUTHEASTWARD PROGRESS THROUGH THE CWA TONIGHT. GUSTY
NORTHWEST WINDS OF 35 TO 45 MPH WILL OCCUR BEHIND THE FRONT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM MST SAT NOV 22 2014

PRIMARY CONCERNS THROUGH THIS WEEKEND WILL BE WINDS AND MOUNTAIN
SNOWFALL. MOST OF THE AREA WITHIN THE HIGH WIND WARNING HAS
VERIFIED THIS AFTERNOON WITH GUSTS AS HIGH AS 76 MPH REPORTED
ALONG I25 AND I80. ELSEWHERE...WINDS HAVE STRUGGLED ACROSS
LOCATIONS SUCH AS THE LARAMIE VALLEY AND THE HIGH PLAINS
IMMEDIATELY EAST OF THE LARAMIE RANGE. BELIEVE THIS IS DUE TO A
COMBINATION OF CLOUDY SKIES AND AN AREA OF POSITIVE OMEGA EAST OF
THE MOUNTAINS. WILL KEEP THE HIGH WIND WARNING OUT FOR THESE
AREAS...BUT THERE IS ONLY A SMALL WINDOW TO SEE GUSTS AROUND 55
MPH SINCE DOWNSLOPE AND SUBSIDENCE WILL BEGIN TO DIMINISH BY LATE
THIS EVENING. ENDED THE HIGH WIND WARNING AT MIDNIGHT TONIGHT
SINCE THE FRONT AND IS TRENDING A BIT FASTER AND SHOULD BE NEAR
THE COLORADO BORDER A FEW HOURS BEFORE MIDNIGHT. AFTER THE FRONT
AND ASSOCIATED TROUGH AXIS ALOFT MOVES THROUGH...WINDS WILL SHIFT
INTO THE NORTHWEST WHICH WILL END THE HIGH WIND EVENT BRIEFLY FOR
THE WIND PRONE AREAS AS WELL. HOWEVER...HIGH WINDS WILL LIKELY
RETURN BY LATE MONDAY NIGHT ACROSS MOST OF SOUTHEAST WYOMING.

SNOW WILL BE ANOTHER CONCERN...PRIMARILY ACROSS THE MOUNTAINS OF
SOUTHEAST WYOMING AND PERHAPS EVEN SOME OF THE HIGH VALLEYS. SNOW
IS DEVELOPING ACROSS THE MOUNTAINS EARLY THIS AFTERNOON WITH SOME
RAIN/SNOW MIX DOWN TO THE VALLEY FLOORS. ANY RAINFALL WILL QUICKLY
CHANGE TO SNOW LATE THIS AFTERNOON AS MUCH COLDER AIR MOVES INTO
THE AREA. THE HEAVIEST SNOW WILL BE TONIGHT...BUT ANOTHER
DISTURBANCE ALOFT WILL PUSH ACROSS THE AREA ON SUNDAY AS WELL
RESULTING IN SOME ENHANCEMENT OF SNOWFALL RATES. HIGH CONFIDENCE
THAT THE MOUNTAINS WILL DO WELL WITH THIS EVENT...SO KEPT THE
WINTER STORM WARNING GOING THROUGH MONDAY FOR 1 TO 2 FEET OF SNOW.
EXPECT THE PRECIPITATION TO BE ENHANCED FURTHER ON THE WEST TO
NORTHWEST FACING SLOPES AND RIDGES DUE TO UPSLOPE FLOW. FOR THE
VALLEYS AND HIGH PLAINS...EXPECT PERHAPS 1 TO 2 INCHES ALONG I80
WEST OF THE LARAMIE RANGE AND FURTHER NORTH ALONG I80 AROUND
DOUGLAS. THE CHEYENNE RIDGE FROM CHEYENNE TO SIDNEY INCLUDING MOST
OF THE NEBRASKA PANHANDLE WILL BE LUCKY TO SEE A DUSTING OF SNOW
DUE TO THE LARGE LOW LEVEL DOWNSLOPE COMPONENT TO THE WINDS. THE
BEST CHANCE TO SEE SOME SNOW WILL BE NEAR THE FRONTAL PASSAGE DUE
TO BRIEF FRONTOGENESIS AND LOW LEVEL DYNAMIC LIFT. THERE IS SOME
CONCERN THAT THE ADJACENT VALLEYS ACROSS SOUTHERN CARBON COUNTY
WILL SEE SOME MODERATE SNOWFALL RATES AS THE WINDS SHIFT INTO THE
NORTHWEST. WILL CONTINUE TO KEEP AN EYE ON THIS THROUGH SUNDAY AS
THE NEXT DISTURBANCE MOVES ACROSS THE AREA. FOR NOW...KEPT 1 TO 3
INCHES OF SNOW IN THESE LOCATIONS WITH 5 INCHES POSSIBLE LOCALLY.

FOR MONDAY...ANOTHER DISTURBANCE ALOFT WILL MOVE ACROSS THE
AREA...RESULTING IN ENHANCED SNOWFALL RATES ACROSS THE MOUNTAINS
AFTER A BRIEF LULL SUNDAY NIGHT. THIS MAY BE THE BEST CHANCE FOR
THE HIGH PLAINS TO RECEIVE SOME WIDESPREAD LIGHT SNOW
ACCUMULATIONS AS WINDS SHIFT INTO THE NORTH.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 300 PM MST SAT NOV 22 2014

STRONG WINDS CONTINUE THROUGH AT LEAST WEDNESDAY. GFS SHOWING A
1041MB SURFACE HIGH OVER WESTERN COLORADO TUESDAY MORNING WITH
A ROUGHLY 10-12MB SURFACE GRADIENT BETWEEN CASPER AND CRAIG.
700MB WINDS FROM THE NORTHWEST AT 50-60KTS WITH A 700MB HEIGHT
GRADIENT AROUND 70 TO 80 MARS BETWEEN CRAIG AND CASPER. ALMOST A
SURE THING FOR WIND WARNING CRITERIA AT LEAST FOR THE WIND PRONE
AREAS AND HAVE BUMPED UP GUIDANCE AT THESE LOCATIONS TO REFLECT
CONFIDENCE IN HIGH WINDS.

WINDS LOOK TO FINALLY EASE SOME THURSDAY AS WE SEE A FRONT DIVE
SOUTHWEST OUT OF THE DAKOTAS AND LAY UP AGAINST THE LARAMIE RANGE.
ECMWF A LITTLE FURTHER NORTHEAST WITH THIS FRONT OVER THE MORE
AGGRESSIVE GFS...FINALLY PUSHING THE BOUNDARY INTO THE LARAMIE
RANGE THURSDAY EVENING. DID GO AHEAD AND LOWER TEMPERATURES SOME
OVER THE NORTHERN PANHANDLE AND OUR EASTERN ZONES TO REFLECT THE
MUCH COLDER AIR BEHIND THE FRONT FOR THURSDAY THROUGH FRIDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1037 PM MST SAT NOV 22 2014

GUSTY WEST TO NORTHWEST WINDS OF 30 TO 40 KT WILL CONTINUE TONIGHT
WITH THE PASSAGE OF A COLD FRONT. OCCASIONAL MVFR CONDITIONS IN
LIGHT SNOW WILL AFFECT MOST TERMINALS TONIGHT THROUGH EARLY SUNDAY
MORNING. MVFR CEILINGS MAY LINGER THROUGH MUCH OF THE DAY SUNDAY
FOR THE RAWLINS/SARATOGA AREAS...WITH THE MOUNTAINS OBSCURED WITH
FALLING/BLOWING SNOW. VFR CONDITIONS SHOULD RESUME LATER SUNDAY
MORNING ELSEWHERE. STRONG AND GUSTY NORTHWEST WINDS WILL PREVAIL
SUNDAY.

&&

.FIRE WEATHER...
ISSUED AT 209 PM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG THROUGH EARLY NEXT WEEK...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED DUE TO COOL TEMPERATURES AND HIGH
RELATIVE HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ112-114.

NE...WIND ADVISORY FROM 9 AM TO 6 PM MST SUNDAY FOR NEZ002-003-
     019>021-054-055-095-096.

&&

$$

UPDATE...MJ
SHORT TERM...TJT
LONG TERM...GCC
AVIATION...MJ
FIRE WEATHER...TJT



000
FXUS63 KUNR 230526
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1026 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 903 PM MST SAT NOV 22 2014

04Z SURFACE ANALYSIS HAD LOW NEAR CYQR WITH COLD FRONT TO KRAP TO
SOUTH CENTRAL WY. COUPLE OF HOURS OF GUSTY WINDS ASSOCIATED WITH
COLD FRONT AS WELL AS SOME -SHRASN. 00Z KUNR SOUNDING SHOWS LIFT
AHEAD OF SHORTWAVE OVER SOUTHEAST MT BEING WASTED ON SATURATION
EARLIER THIS EVENING. LATEST RADAR/OBSERVATIONS DO SUGGEST LOWER
TROPOSPHERE MOISTENING ENOUGH FOR PRECIPITATION TO REACH THE
GROUND...ESPECIALLY OVER NORTHWEST SD SO HAVE RAISED POPS THERE.

00Z GUIDANCE STILL SHOWS VERY WINDY DAY FOR MUCH OF THE AREA
SUNDAY. BUFKIT MOMENTUM TRANSFER INDICATES HIGH WIND WARNING
CRITERIA WINDS FROM K2WX TO KRAP DURING PEAK MIXING LATER SUNDAY
MORNING THROUGH LATE SUNDAY AFTERNOON...IN CONTRAST TO LESSER MOS
GUIDANCE WINDS. 40-50KT 850MB WINDS NOTED WITH SLIGHTLY HIGHER
VALUES HIGHER UP. STRONG SUBSIDENCE NOTED BEHIND TONIGHT/S
SHORTWAVE ALONG WITH WEAK COLD AIR ADVECTION DURING PEAK HEATING.
WILL CONVERT WATCH TO WARNING AND EXPAND ALONG THE FOOTHILLS A BIT
WITH UPDATE.

&&

.SHORT TERM...THIS EVENING THROUGH SUNDAY NIGHT
ISSUED AT 426 PM MST SAT NOV 22 2014

DEEPENING NW CONUS UPPER TROUGH WILL ADVECT THROUGH THE REGION
THROUGH SUNDAY...SUPPORTING A COLD FRONT INTO THE AREA...WITH
CHANCES FOR SNOW AND INCREASING WINDS. THERMAL RIDGE HAS SUPPORTED
A MILD DAY ACROSS THE AREA...ESP WHERE ENHANCED LOCAL MIXING HAS
OCCURRED. HOWEVER...INCREASING LSA WITH A LL COLD FRONT WILL
SUPPORT A WEAK FGEN BAND OF PRECIP ACROSS THE AREA TONIGHT.
SECONDARY COLD FRONT WITH STEEP LL LAPSE RATES AND CYCLONIC FLOW
ALOFT WILL THEN SUPPORT INCREASING CHANCES FOR DIURNALLY DRIVEN
SNOW SHOWERS SUNDAY...WITH FAVORABLE UPSLOPE FORCING OVER THE
NORTHERN HILLS. ACTIVE NW FLOW WILL SUSTAIN THROUGH SUNDAY
NIGHT...WITH ANOTHER IMPULSE EXPECTED TO INFLUENCE THE WESTERN FA
LATE SUNDAY.

TONIGHT...SPLITTING NW CONUS UPPER TROUGH WILL SUPPORT A WEAK HIGH
CENTERED FGEN RESPONSE OVER THE REGION WITH INCREASING MID LEVEL
MOISTURE. STEEP MID LEVEL LAPSE RATES COMBINED WITH SUFFICIENT MID
LEVEL MOISTURE AND INCREASING UVM SHOULD BE ENOUGH TO SUPPORT SCT
RAIN/SNOW SHOWERS OVER THE REGION...ESP NE WY WHERE BETTER FORCING
FOR ACCENT WILL BE IN PLACE. ANY PRECIP WILL MAINLY BE IN THE FORM OF
RAIN THIS EVENING...QUICKLY TRANSITIONING TO SNOW OVERNIGHT GIVEN
COOLING THERMAL FIELDS. ANY SNOW AMOUNTS WILL GENERALLY BE LESS THAN
ONE INCH. LL FLOW WILL VEER NW TONIGHT AND INCREASE AFTER MIDNIGHT.
INITIAL CAA PUSH AND PRESSURE RISES MAY SUPPORT A PERIOD OF NEAR ADV
WINDS AROUND KRAP AFTER MIDNIGHT. HOWEVER...WINDS SHOULD GENERALLY
REMAIN TAME UNTIL LATER SUNDAY MORNING.

SUNDAY...SECONDARY CAA PUSH AND INCREASING LL FLOW WILL SUPPORT A
WINDY DAY ACROSS THE REGION. MEAN BL FLOW PROGS SUPPORT SUSTAINED
WINDS OF 30-35 KNOTS ESP ACROSS FAR NW SD. BUFR PROGS INDICATE THE
POTENTIAL FOR WINDS OF 50 KNOTS TO MIX DOWN...ESP WITH THE SECONDARY
PRESSURE RISE SURGE EARLY SUNDAY AFTERNOON ACROSS THE FAR NW. IN
ADDITION...COLD POCKET ALOFT COMBINED WITH DIURNAL HEATING WILL
SUPPORT THE DEVELOPMENT OF SNOW SHOWERS...WITH LOCAL ENHANCED
DOWNWARD MOMENTUM TRANSPORT POSSIBLE IN THE VICINITY OF ANY SHOWER.
HAVE DECIDED TO ISSUE A WIND ADV FOR MUCH OF THE SD
PLAINS...RETAINING A HIGH WIND WATCH ACROSS THE FAR NW WHERE THE
BEST POTENTIAL FOR DOWNWARD MOMENTUM TRANSPORT OF 50 KNOT FLOW WILL
RESIDE. MEAN MODEL TRENDS HAVE SUPPORTED SLIGHTLY WEAKER WINDS
ACROSS THE AREA...BUT WOULD LIKE TO HAVE ANOTHER FORECAST RUN OR TWO
TO SEE IF THIS TREND SUSTAINS. THERE IS ALSO THE POTENTIAL FOR
LOCALIZED STRONG WINDS ALONG THE PLAINS OF THE EASTERN BLACK
HILLS...INCLUDING RAPID CITY...WITH NEAR HIGH WIND WARNING POSSIBLE.
HOWEVER...GIVEN THE LOW POTENTIAL/SHORT DURATION/AND LOCALIZED
NATURE...FEEL A WIND ADV IS MORE PRUDENT. THE OTHER HIGHLIGHT WILL
BE INCREASINGLY FAVORABLE CONDITIONS FOR UPSLOPE SNOWS ACROSS THE
NORTHERN BLACK HILLS...MAINLY FROM THE BEAR LODGE MOUNTAINS TO
CHEYENNE CROSSING. INCREASING FROUDE/MOISTURE/AND FLOW WITH COOLING
THERMAL FIELDS IN STEEP LL LAPSE RATES WILL SUPPORT A DECENT PERIOD
OF UPSLOPE FORCING...EXTENDING INTO THE DGZ. 1 TO 3 INCHES WITH
LOCALLY HIGHER AMOUNTS WILL BE POSSIBLE IN THIS AREA. SNOW WILL WIND
DOWN SUNDAY EVENING AS THE BL DRIES. HOWEVER...AS SECONDARY IMPULSE
WILL LEAD TO RENEWED CHANCES FOR SNOW...MAINLY NE WY LATE SUNDAY
NIGHT.

&&

.LONG TERM...MONDAY THROUGH SATURDAY
ISSUED AT 426 PM MST SAT NOV 22 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW ALOFT WILL
CONTINUE ACROSS THE NORTHERN HIGH PLAINS EARLY NEXT WEEK. SEVERAL
WEAK DISTURBANCES WITHIN NORTHWEST FLOW WILL SLIDE THROUGH...BRINGING
A GOOD DEAL OF CLOUDINESS AND CHANCES FOR SNOW SHOWERS AT TIMES
THROUGH WEDNESDAY. THE BEST CHANCES FOR SNOW WILL GENERALLY BE
ACROSS NORTHEAST WY AND THE NORTHERN BLACK HILLS AREA.

FOR THE HOLIDAY PERIOD...THE LATEST RUNS OF THE GFS...ECMWF...AND
CANADIAN HAVE ALL FLIPPED BACK TO A COLDER REGIME FOR LATE IN THE
WEEK AS A CANADIAN COLD FRONT IS PROGGED TO SLIDE SOUTH THROUGH THE
AREA LATE WEDNESDAY/WEDNESDAY NIGHT. WILL TREND COLDER AGAIN FOR
THANKSGIVING DAY AND THE REST OF THE EXTENDED...BUT UNCERTAINTY
STILL EXISTS WITH REGARD TO TEMPS. IT DOES CONTINUE TO LOOK MAINLY
DRY DURING THE PERIOD THOUGH.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1022 PM MST SAT NOV 22 2014

A COLD FRONT WILL EXIT THE AREA OVERNIGHT. BEHIND IT GUSTY
NORTHWEST WINDS ARE EXPECTED FOR A COUPLE OF HOURS TONIGHT. WINDS
WILL PICK UP AGAIN SUNDAY MORNING AS STRONG NORTHWEST WINDS
DEVELOP OVER THE NORTHWEST SD PLAINS. LOCAL MVFR CIGS MAY OCCUR
BEHIND THE COLD FRONT TONIGHT...WITH SOME CLEARING OVERNIGHT.
ADDITIONAL LOCAL MVFR CIGS MAY OCCUR SUNDAY WITH ANY SNOW
SHOWERS...ESPECIALLY OVER THE BLACK HILLS.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY FROM 8 AM MST /9 AM CST/ TO 8 PM MST /9 PM CST/
     SUNDAY FOR SDZ014-025-027-032-041-043-044-046-047-049.

     HIGH WIND WARNING FROM 8 AM TO 8 PM MST SUNDAY FOR SDZ001-002-
     012-013-026-031-072-073.

WY...NONE.
&&

$$

UPDATE...HELGESON
SHORT TERM...JC
LONG TERM...26
AVIATION...HELGESON




000
FXUS63 KUNR 230526
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1026 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 903 PM MST SAT NOV 22 2014

04Z SURFACE ANALYSIS HAD LOW NEAR CYQR WITH COLD FRONT TO KRAP TO
SOUTH CENTRAL WY. COUPLE OF HOURS OF GUSTY WINDS ASSOCIATED WITH
COLD FRONT AS WELL AS SOME -SHRASN. 00Z KUNR SOUNDING SHOWS LIFT
AHEAD OF SHORTWAVE OVER SOUTHEAST MT BEING WASTED ON SATURATION
EARLIER THIS EVENING. LATEST RADAR/OBSERVATIONS DO SUGGEST LOWER
TROPOSPHERE MOISTENING ENOUGH FOR PRECIPITATION TO REACH THE
GROUND...ESPECIALLY OVER NORTHWEST SD SO HAVE RAISED POPS THERE.

00Z GUIDANCE STILL SHOWS VERY WINDY DAY FOR MUCH OF THE AREA
SUNDAY. BUFKIT MOMENTUM TRANSFER INDICATES HIGH WIND WARNING
CRITERIA WINDS FROM K2WX TO KRAP DURING PEAK MIXING LATER SUNDAY
MORNING THROUGH LATE SUNDAY AFTERNOON...IN CONTRAST TO LESSER MOS
GUIDANCE WINDS. 40-50KT 850MB WINDS NOTED WITH SLIGHTLY HIGHER
VALUES HIGHER UP. STRONG SUBSIDENCE NOTED BEHIND TONIGHT/S
SHORTWAVE ALONG WITH WEAK COLD AIR ADVECTION DURING PEAK HEATING.
WILL CONVERT WATCH TO WARNING AND EXPAND ALONG THE FOOTHILLS A BIT
WITH UPDATE.

&&

.SHORT TERM...THIS EVENING THROUGH SUNDAY NIGHT
ISSUED AT 426 PM MST SAT NOV 22 2014

DEEPENING NW CONUS UPPER TROUGH WILL ADVECT THROUGH THE REGION
THROUGH SUNDAY...SUPPORTING A COLD FRONT INTO THE AREA...WITH
CHANCES FOR SNOW AND INCREASING WINDS. THERMAL RIDGE HAS SUPPORTED
A MILD DAY ACROSS THE AREA...ESP WHERE ENHANCED LOCAL MIXING HAS
OCCURRED. HOWEVER...INCREASING LSA WITH A LL COLD FRONT WILL
SUPPORT A WEAK FGEN BAND OF PRECIP ACROSS THE AREA TONIGHT.
SECONDARY COLD FRONT WITH STEEP LL LAPSE RATES AND CYCLONIC FLOW
ALOFT WILL THEN SUPPORT INCREASING CHANCES FOR DIURNALLY DRIVEN
SNOW SHOWERS SUNDAY...WITH FAVORABLE UPSLOPE FORCING OVER THE
NORTHERN HILLS. ACTIVE NW FLOW WILL SUSTAIN THROUGH SUNDAY
NIGHT...WITH ANOTHER IMPULSE EXPECTED TO INFLUENCE THE WESTERN FA
LATE SUNDAY.

TONIGHT...SPLITTING NW CONUS UPPER TROUGH WILL SUPPORT A WEAK HIGH
CENTERED FGEN RESPONSE OVER THE REGION WITH INCREASING MID LEVEL
MOISTURE. STEEP MID LEVEL LAPSE RATES COMBINED WITH SUFFICIENT MID
LEVEL MOISTURE AND INCREASING UVM SHOULD BE ENOUGH TO SUPPORT SCT
RAIN/SNOW SHOWERS OVER THE REGION...ESP NE WY WHERE BETTER FORCING
FOR ACCENT WILL BE IN PLACE. ANY PRECIP WILL MAINLY BE IN THE FORM OF
RAIN THIS EVENING...QUICKLY TRANSITIONING TO SNOW OVERNIGHT GIVEN
COOLING THERMAL FIELDS. ANY SNOW AMOUNTS WILL GENERALLY BE LESS THAN
ONE INCH. LL FLOW WILL VEER NW TONIGHT AND INCREASE AFTER MIDNIGHT.
INITIAL CAA PUSH AND PRESSURE RISES MAY SUPPORT A PERIOD OF NEAR ADV
WINDS AROUND KRAP AFTER MIDNIGHT. HOWEVER...WINDS SHOULD GENERALLY
REMAIN TAME UNTIL LATER SUNDAY MORNING.

SUNDAY...SECONDARY CAA PUSH AND INCREASING LL FLOW WILL SUPPORT A
WINDY DAY ACROSS THE REGION. MEAN BL FLOW PROGS SUPPORT SUSTAINED
WINDS OF 30-35 KNOTS ESP ACROSS FAR NW SD. BUFR PROGS INDICATE THE
POTENTIAL FOR WINDS OF 50 KNOTS TO MIX DOWN...ESP WITH THE SECONDARY
PRESSURE RISE SURGE EARLY SUNDAY AFTERNOON ACROSS THE FAR NW. IN
ADDITION...COLD POCKET ALOFT COMBINED WITH DIURNAL HEATING WILL
SUPPORT THE DEVELOPMENT OF SNOW SHOWERS...WITH LOCAL ENHANCED
DOWNWARD MOMENTUM TRANSPORT POSSIBLE IN THE VICINITY OF ANY SHOWER.
HAVE DECIDED TO ISSUE A WIND ADV FOR MUCH OF THE SD
PLAINS...RETAINING A HIGH WIND WATCH ACROSS THE FAR NW WHERE THE
BEST POTENTIAL FOR DOWNWARD MOMENTUM TRANSPORT OF 50 KNOT FLOW WILL
RESIDE. MEAN MODEL TRENDS HAVE SUPPORTED SLIGHTLY WEAKER WINDS
ACROSS THE AREA...BUT WOULD LIKE TO HAVE ANOTHER FORECAST RUN OR TWO
TO SEE IF THIS TREND SUSTAINS. THERE IS ALSO THE POTENTIAL FOR
LOCALIZED STRONG WINDS ALONG THE PLAINS OF THE EASTERN BLACK
HILLS...INCLUDING RAPID CITY...WITH NEAR HIGH WIND WARNING POSSIBLE.
HOWEVER...GIVEN THE LOW POTENTIAL/SHORT DURATION/AND LOCALIZED
NATURE...FEEL A WIND ADV IS MORE PRUDENT. THE OTHER HIGHLIGHT WILL
BE INCREASINGLY FAVORABLE CONDITIONS FOR UPSLOPE SNOWS ACROSS THE
NORTHERN BLACK HILLS...MAINLY FROM THE BEAR LODGE MOUNTAINS TO
CHEYENNE CROSSING. INCREASING FROUDE/MOISTURE/AND FLOW WITH COOLING
THERMAL FIELDS IN STEEP LL LAPSE RATES WILL SUPPORT A DECENT PERIOD
OF UPSLOPE FORCING...EXTENDING INTO THE DGZ. 1 TO 3 INCHES WITH
LOCALLY HIGHER AMOUNTS WILL BE POSSIBLE IN THIS AREA. SNOW WILL WIND
DOWN SUNDAY EVENING AS THE BL DRIES. HOWEVER...AS SECONDARY IMPULSE
WILL LEAD TO RENEWED CHANCES FOR SNOW...MAINLY NE WY LATE SUNDAY
NIGHT.

&&

.LONG TERM...MONDAY THROUGH SATURDAY
ISSUED AT 426 PM MST SAT NOV 22 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW ALOFT WILL
CONTINUE ACROSS THE NORTHERN HIGH PLAINS EARLY NEXT WEEK. SEVERAL
WEAK DISTURBANCES WITHIN NORTHWEST FLOW WILL SLIDE THROUGH...BRINGING
A GOOD DEAL OF CLOUDINESS AND CHANCES FOR SNOW SHOWERS AT TIMES
THROUGH WEDNESDAY. THE BEST CHANCES FOR SNOW WILL GENERALLY BE
ACROSS NORTHEAST WY AND THE NORTHERN BLACK HILLS AREA.

FOR THE HOLIDAY PERIOD...THE LATEST RUNS OF THE GFS...ECMWF...AND
CANADIAN HAVE ALL FLIPPED BACK TO A COLDER REGIME FOR LATE IN THE
WEEK AS A CANADIAN COLD FRONT IS PROGGED TO SLIDE SOUTH THROUGH THE
AREA LATE WEDNESDAY/WEDNESDAY NIGHT. WILL TREND COLDER AGAIN FOR
THANKSGIVING DAY AND THE REST OF THE EXTENDED...BUT UNCERTAINTY
STILL EXISTS WITH REGARD TO TEMPS. IT DOES CONTINUE TO LOOK MAINLY
DRY DURING THE PERIOD THOUGH.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1022 PM MST SAT NOV 22 2014

A COLD FRONT WILL EXIT THE AREA OVERNIGHT. BEHIND IT GUSTY
NORTHWEST WINDS ARE EXPECTED FOR A COUPLE OF HOURS TONIGHT. WINDS
WILL PICK UP AGAIN SUNDAY MORNING AS STRONG NORTHWEST WINDS
DEVELOP OVER THE NORTHWEST SD PLAINS. LOCAL MVFR CIGS MAY OCCUR
BEHIND THE COLD FRONT TONIGHT...WITH SOME CLEARING OVERNIGHT.
ADDITIONAL LOCAL MVFR CIGS MAY OCCUR SUNDAY WITH ANY SNOW
SHOWERS...ESPECIALLY OVER THE BLACK HILLS.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY FROM 8 AM MST /9 AM CST/ TO 8 PM MST /9 PM CST/
     SUNDAY FOR SDZ014-025-027-032-041-043-044-046-047-049.

     HIGH WIND WARNING FROM 8 AM TO 8 PM MST SUNDAY FOR SDZ001-002-
     012-013-026-031-072-073.

WY...NONE.
&&

$$

UPDATE...HELGESON
SHORT TERM...JC
LONG TERM...26
AVIATION...HELGESON





000
FXUS65 KCYS 230437
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
935 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 932 PM MST SAT NOV 22 2014

WINDS PER SURFACE/HIGHWAY OBSERVATIONS THE PAST FEW HOURS HAVE
SHOWN A GRADUAL DECREASING TREND...AND THE THREAT FOR HIGH WINDS
TONIGHT HAS ENDED. THUS HAVE CANCELLED HIGH WIND WARNINGS. COLD
FRONT HAS MOVED THROUGH RIVERTON AND CASPER AND WILL CONTINUE ITS
STEADY SOUTHEASTWARD PROGRESS THROUGH THE CWA TONIGHT. GUSTY
NORTHWEST WINDS OF 35 TO 45 MPH WILL OCCUR BEHIND THE FRONT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM MST SAT NOV 22 2014

PRIMARY CONCERNS THROUGH THIS WEEKEND WILL BE WINDS AND MOUNTAIN
SNOWFALL. MOST OF THE AREA WITHIN THE HIGH WIND WARNING HAS
VERIFIED THIS AFTERNOON WITH GUSTS AS HIGH AS 76 MPH REPORTED
ALONG I25 AND I80. ELSEWHERE...WINDS HAVE STRUGGLED ACROSS
LOCATIONS SUCH AS THE LARAMIE VALLEY AND THE HIGH PLAINS
IMMEDIATELY EAST OF THE LARAMIE RANGE. BELIEVE THIS IS DUE TO A
COMBINATION OF CLOUDY SKIES AND AN AREA OF POSITIVE OMEGA EAST OF
THE MOUNTAINS. WILL KEEP THE HIGH WIND WARNING OUT FOR THESE
AREAS...BUT THERE IS ONLY A SMALL WINDOW TO SEE GUSTS AROUND 55
MPH SINCE DOWNSLOPE AND SUBSIDENCE WILL BEGIN TO DIMINISH BY LATE
THIS EVENING. ENDED THE HIGH WIND WARNING AT MIDNIGHT TONIGHT
SINCE THE FRONT AND IS TRENDING A BIT FASTER AND SHOULD BE NEAR
THE COLORADO BORDER A FEW HOURS BEFORE MIDNIGHT. AFTER THE FRONT
AND ASSOCIATED TROUGH AXIS ALOFT MOVES THROUGH...WINDS WILL SHIFT
INTO THE NORTHWEST WHICH WILL END THE HIGH WIND EVENT BRIEFLY FOR
THE WIND PRONE AREAS AS WELL. HOWEVER...HIGH WINDS WILL LIKELY
RETURN BY LATE MONDAY NIGHT ACROSS MOST OF SOUTHEAST WYOMING.

SNOW WILL BE ANOTHER CONCERN...PRIMARILY ACROSS THE MOUNTAINS OF
SOUTHEAST WYOMING AND PERHAPS EVEN SOME OF THE HIGH VALLEYS. SNOW
IS DEVELOPING ACROSS THE MOUNTAINS EARLY THIS AFTERNOON WITH SOME
RAIN/SNOW MIX DOWN TO THE VALLEY FLOORS. ANY RAINFALL WILL QUICKLY
CHANGE TO SNOW LATE THIS AFTERNOON AS MUCH COLDER AIR MOVES INTO
THE AREA. THE HEAVIEST SNOW WILL BE TONIGHT...BUT ANOTHER
DISTURBANCE ALOFT WILL PUSH ACROSS THE AREA ON SUNDAY AS WELL
RESULTING IN SOME ENHANCEMENT OF SNOWFALL RATES. HIGH CONFIDENCE
THAT THE MOUNTAINS WILL DO WELL WITH THIS EVENT...SO KEPT THE
WINTER STORM WARNING GOING THROUGH MONDAY FOR 1 TO 2 FEET OF SNOW.
EXPECT THE PRECIPITATION TO BE ENHANCED FURTHER ON THE WEST TO
NORTHWEST FACING SLOPES AND RIDGES DUE TO UPSLOPE FLOW. FOR THE
VALLEYS AND HIGH PLAINS...EXPECT PERHAPS 1 TO 2 INCHES ALONG I80
WEST OF THE LARAMIE RANGE AND FURTHER NORTH ALONG I80 AROUND
DOUGLAS. THE CHEYENNE RIDGE FROM CHEYENNE TO SIDNEY INCLUDING MOST
OF THE NEBRASKA PANHANDLE WILL BE LUCKY TO SEE A DUSTING OF SNOW
DUE TO THE LARGE LOW LEVEL DOWNSLOPE COMPONENT TO THE WINDS. THE
BEST CHANCE TO SEE SOME SNOW WILL BE NEAR THE FRONTAL PASSAGE DUE
TO BRIEF FRONTOGENESIS AND LOW LEVEL DYNAMIC LIFT. THERE IS SOME
CONCERN THAT THE ADJACENT VALLEYS ACROSS SOUTHERN CARBON COUNTY
WILL SEE SOME MODERATE SNOWFALL RATES AS THE WINDS SHIFT INTO THE
NORTHWEST. WILL CONTINUE TO KEEP AN EYE ON THIS THROUGH SUNDAY AS
THE NEXT DISTURBANCE MOVES ACROSS THE AREA. FOR NOW...KEPT 1 TO 3
INCHES OF SNOW IN THESE LOCATIONS WITH 5 INCHES POSSIBLE LOCALLY.

FOR MONDAY...ANOTHER DISTURBANCE ALOFT WILL MOVE ACROSS THE
AREA...RESULTING IN ENHANCED SNOWFALL RATES ACROSS THE MOUNTAINS
AFTER A BRIEF LULL SUNDAY NIGHT. THIS MAY BE THE BEST CHANCE FOR
THE HIGH PLAINS TO RECEIVE SOME WIDESPREAD LIGHT SNOW
ACCUMULATIONS AS WINDS SHIFT INTO THE NORTH.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 300 PM MST SAT NOV 22 2014

STRONG WINDS CONTINUE THROUGH AT LEAST WEDNESDAY. GFS SHOWING A
1041MB SURFACE HIGH OVER WESTERN COLORADO TUESDAY MORNING WITH
A ROUGHLY 10-12MB SURFACE GRADIENT BETWEEN CASPER AND CRAIG.
700MB WINDS FROM THE NORTHWEST AT 50-60KTS WITH A 700MB HEIGHT
GRADIENT AROUND 70 TO 80 MARS BETWEEN CRAIG AND CASPER. ALMOST A
SURE THING FOR WIND WARNING CRITERIA AT LEAST FOR THE WIND PRONE
AREAS AND HAVE BUMPED UP GUIDANCE AT THESE LOCATIONS TO REFLECT
CONFIDENCE IN HIGH WINDS.

WINDS LOOK TO FINALLY EASE SOME THURSDAY AS WE SEE A FRONT DIVE
SOUTHWEST OUT OF THE DAKOTAS AND LAY UP AGAINST THE LARAMIE RANGE.
ECMWF A LITTLE FURTHER NORTHEAST WITH THIS FRONT OVER THE MORE
AGGRESSIVE GFS...FINALLY PUSHING THE BOUNDARY INTO THE LARAMIE
RANGE THURSDAY EVENING. DID GO AHEAD AND LOWER TEMPERATURES SOME
OVER THE NORTHERN PANHANDLE AND OUR EASTERN ZONES TO REFLECT THE
MUCH COLDER AIR BEHIND THE FRONT FOR THURSDAY THROUGH FRIDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 453 PM MST SAT NOV 22 2014

STRONG AND GUSTY WESTERLY WINDS WILL CONTINUE TONIGHT WITH THE
PASSAGE OF A PACIFIC COLD FRONT. GUSTS TO 50 KT WILL STILL BE
POSSIBLE EARLY THIS EVENING...MAINLY INVOF THE MOUNTAINS. GUSTS
WILL DECREASE TO 30-40 KT LATER THIS EVENING AND OVERNIGHT. MVFR
CONDITIONS IN RAIN/SNOW SHOWERS WEST OF THE LARAMIE RANGE WILL
SPREAD EAST ONTO THE PLAINS TONIGHT...WITH OCCASIONAL IFR POSSIBLE.
PRECIPITATION WILL TAPER OFF WITH IMPROVING CIGS/VSBYS SUNDAY
MORNING.

&&

.FIRE WEATHER...
ISSUED AT 209 PM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG THROUGH EARLY NEXT WEEK...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED DUE TO COOL TEMPERATURES AND HIGH
RELATIVE HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ112-114.

NE...WIND ADVISORY FROM 9 AM TO 6 PM MST SUNDAY FOR NEZ002-003-
     019>021-054-055-095-096.

&&

$$

UPDATE...MJ
SHORT TERM...TJT
LONG TERM...GCC
AVIATION...MJ
FIRE WEATHER...TJT



000
FXUS65 KCYS 230437
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
935 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 932 PM MST SAT NOV 22 2014

WINDS PER SURFACE/HIGHWAY OBSERVATIONS THE PAST FEW HOURS HAVE
SHOWN A GRADUAL DECREASING TREND...AND THE THREAT FOR HIGH WINDS
TONIGHT HAS ENDED. THUS HAVE CANCELLED HIGH WIND WARNINGS. COLD
FRONT HAS MOVED THROUGH RIVERTON AND CASPER AND WILL CONTINUE ITS
STEADY SOUTHEASTWARD PROGRESS THROUGH THE CWA TONIGHT. GUSTY
NORTHWEST WINDS OF 35 TO 45 MPH WILL OCCUR BEHIND THE FRONT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM MST SAT NOV 22 2014

PRIMARY CONCERNS THROUGH THIS WEEKEND WILL BE WINDS AND MOUNTAIN
SNOWFALL. MOST OF THE AREA WITHIN THE HIGH WIND WARNING HAS
VERIFIED THIS AFTERNOON WITH GUSTS AS HIGH AS 76 MPH REPORTED
ALONG I25 AND I80. ELSEWHERE...WINDS HAVE STRUGGLED ACROSS
LOCATIONS SUCH AS THE LARAMIE VALLEY AND THE HIGH PLAINS
IMMEDIATELY EAST OF THE LARAMIE RANGE. BELIEVE THIS IS DUE TO A
COMBINATION OF CLOUDY SKIES AND AN AREA OF POSITIVE OMEGA EAST OF
THE MOUNTAINS. WILL KEEP THE HIGH WIND WARNING OUT FOR THESE
AREAS...BUT THERE IS ONLY A SMALL WINDOW TO SEE GUSTS AROUND 55
MPH SINCE DOWNSLOPE AND SUBSIDENCE WILL BEGIN TO DIMINISH BY LATE
THIS EVENING. ENDED THE HIGH WIND WARNING AT MIDNIGHT TONIGHT
SINCE THE FRONT AND IS TRENDING A BIT FASTER AND SHOULD BE NEAR
THE COLORADO BORDER A FEW HOURS BEFORE MIDNIGHT. AFTER THE FRONT
AND ASSOCIATED TROUGH AXIS ALOFT MOVES THROUGH...WINDS WILL SHIFT
INTO THE NORTHWEST WHICH WILL END THE HIGH WIND EVENT BRIEFLY FOR
THE WIND PRONE AREAS AS WELL. HOWEVER...HIGH WINDS WILL LIKELY
RETURN BY LATE MONDAY NIGHT ACROSS MOST OF SOUTHEAST WYOMING.

SNOW WILL BE ANOTHER CONCERN...PRIMARILY ACROSS THE MOUNTAINS OF
SOUTHEAST WYOMING AND PERHAPS EVEN SOME OF THE HIGH VALLEYS. SNOW
IS DEVELOPING ACROSS THE MOUNTAINS EARLY THIS AFTERNOON WITH SOME
RAIN/SNOW MIX DOWN TO THE VALLEY FLOORS. ANY RAINFALL WILL QUICKLY
CHANGE TO SNOW LATE THIS AFTERNOON AS MUCH COLDER AIR MOVES INTO
THE AREA. THE HEAVIEST SNOW WILL BE TONIGHT...BUT ANOTHER
DISTURBANCE ALOFT WILL PUSH ACROSS THE AREA ON SUNDAY AS WELL
RESULTING IN SOME ENHANCEMENT OF SNOWFALL RATES. HIGH CONFIDENCE
THAT THE MOUNTAINS WILL DO WELL WITH THIS EVENT...SO KEPT THE
WINTER STORM WARNING GOING THROUGH MONDAY FOR 1 TO 2 FEET OF SNOW.
EXPECT THE PRECIPITATION TO BE ENHANCED FURTHER ON THE WEST TO
NORTHWEST FACING SLOPES AND RIDGES DUE TO UPSLOPE FLOW. FOR THE
VALLEYS AND HIGH PLAINS...EXPECT PERHAPS 1 TO 2 INCHES ALONG I80
WEST OF THE LARAMIE RANGE AND FURTHER NORTH ALONG I80 AROUND
DOUGLAS. THE CHEYENNE RIDGE FROM CHEYENNE TO SIDNEY INCLUDING MOST
OF THE NEBRASKA PANHANDLE WILL BE LUCKY TO SEE A DUSTING OF SNOW
DUE TO THE LARGE LOW LEVEL DOWNSLOPE COMPONENT TO THE WINDS. THE
BEST CHANCE TO SEE SOME SNOW WILL BE NEAR THE FRONTAL PASSAGE DUE
TO BRIEF FRONTOGENESIS AND LOW LEVEL DYNAMIC LIFT. THERE IS SOME
CONCERN THAT THE ADJACENT VALLEYS ACROSS SOUTHERN CARBON COUNTY
WILL SEE SOME MODERATE SNOWFALL RATES AS THE WINDS SHIFT INTO THE
NORTHWEST. WILL CONTINUE TO KEEP AN EYE ON THIS THROUGH SUNDAY AS
THE NEXT DISTURBANCE MOVES ACROSS THE AREA. FOR NOW...KEPT 1 TO 3
INCHES OF SNOW IN THESE LOCATIONS WITH 5 INCHES POSSIBLE LOCALLY.

FOR MONDAY...ANOTHER DISTURBANCE ALOFT WILL MOVE ACROSS THE
AREA...RESULTING IN ENHANCED SNOWFALL RATES ACROSS THE MOUNTAINS
AFTER A BRIEF LULL SUNDAY NIGHT. THIS MAY BE THE BEST CHANCE FOR
THE HIGH PLAINS TO RECEIVE SOME WIDESPREAD LIGHT SNOW
ACCUMULATIONS AS WINDS SHIFT INTO THE NORTH.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 300 PM MST SAT NOV 22 2014

STRONG WINDS CONTINUE THROUGH AT LEAST WEDNESDAY. GFS SHOWING A
1041MB SURFACE HIGH OVER WESTERN COLORADO TUESDAY MORNING WITH
A ROUGHLY 10-12MB SURFACE GRADIENT BETWEEN CASPER AND CRAIG.
700MB WINDS FROM THE NORTHWEST AT 50-60KTS WITH A 700MB HEIGHT
GRADIENT AROUND 70 TO 80 MARS BETWEEN CRAIG AND CASPER. ALMOST A
SURE THING FOR WIND WARNING CRITERIA AT LEAST FOR THE WIND PRONE
AREAS AND HAVE BUMPED UP GUIDANCE AT THESE LOCATIONS TO REFLECT
CONFIDENCE IN HIGH WINDS.

WINDS LOOK TO FINALLY EASE SOME THURSDAY AS WE SEE A FRONT DIVE
SOUTHWEST OUT OF THE DAKOTAS AND LAY UP AGAINST THE LARAMIE RANGE.
ECMWF A LITTLE FURTHER NORTHEAST WITH THIS FRONT OVER THE MORE
AGGRESSIVE GFS...FINALLY PUSHING THE BOUNDARY INTO THE LARAMIE
RANGE THURSDAY EVENING. DID GO AHEAD AND LOWER TEMPERATURES SOME
OVER THE NORTHERN PANHANDLE AND OUR EASTERN ZONES TO REFLECT THE
MUCH COLDER AIR BEHIND THE FRONT FOR THURSDAY THROUGH FRIDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 453 PM MST SAT NOV 22 2014

STRONG AND GUSTY WESTERLY WINDS WILL CONTINUE TONIGHT WITH THE
PASSAGE OF A PACIFIC COLD FRONT. GUSTS TO 50 KT WILL STILL BE
POSSIBLE EARLY THIS EVENING...MAINLY INVOF THE MOUNTAINS. GUSTS
WILL DECREASE TO 30-40 KT LATER THIS EVENING AND OVERNIGHT. MVFR
CONDITIONS IN RAIN/SNOW SHOWERS WEST OF THE LARAMIE RANGE WILL
SPREAD EAST ONTO THE PLAINS TONIGHT...WITH OCCASIONAL IFR POSSIBLE.
PRECIPITATION WILL TAPER OFF WITH IMPROVING CIGS/VSBYS SUNDAY
MORNING.

&&

.FIRE WEATHER...
ISSUED AT 209 PM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG THROUGH EARLY NEXT WEEK...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED DUE TO COOL TEMPERATURES AND HIGH
RELATIVE HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ112-114.

NE...WIND ADVISORY FROM 9 AM TO 6 PM MST SUNDAY FOR NEZ002-003-
     019>021-054-055-095-096.

&&

$$

UPDATE...MJ
SHORT TERM...TJT
LONG TERM...GCC
AVIATION...MJ
FIRE WEATHER...TJT




000
FXUS65 KCYS 230437
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
935 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 932 PM MST SAT NOV 22 2014

WINDS PER SURFACE/HIGHWAY OBSERVATIONS THE PAST FEW HOURS HAVE
SHOWN A GRADUAL DECREASING TREND...AND THE THREAT FOR HIGH WINDS
TONIGHT HAS ENDED. THUS HAVE CANCELLED HIGH WIND WARNINGS. COLD
FRONT HAS MOVED THROUGH RIVERTON AND CASPER AND WILL CONTINUE ITS
STEADY SOUTHEASTWARD PROGRESS THROUGH THE CWA TONIGHT. GUSTY
NORTHWEST WINDS OF 35 TO 45 MPH WILL OCCUR BEHIND THE FRONT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM MST SAT NOV 22 2014

PRIMARY CONCERNS THROUGH THIS WEEKEND WILL BE WINDS AND MOUNTAIN
SNOWFALL. MOST OF THE AREA WITHIN THE HIGH WIND WARNING HAS
VERIFIED THIS AFTERNOON WITH GUSTS AS HIGH AS 76 MPH REPORTED
ALONG I25 AND I80. ELSEWHERE...WINDS HAVE STRUGGLED ACROSS
LOCATIONS SUCH AS THE LARAMIE VALLEY AND THE HIGH PLAINS
IMMEDIATELY EAST OF THE LARAMIE RANGE. BELIEVE THIS IS DUE TO A
COMBINATION OF CLOUDY SKIES AND AN AREA OF POSITIVE OMEGA EAST OF
THE MOUNTAINS. WILL KEEP THE HIGH WIND WARNING OUT FOR THESE
AREAS...BUT THERE IS ONLY A SMALL WINDOW TO SEE GUSTS AROUND 55
MPH SINCE DOWNSLOPE AND SUBSIDENCE WILL BEGIN TO DIMINISH BY LATE
THIS EVENING. ENDED THE HIGH WIND WARNING AT MIDNIGHT TONIGHT
SINCE THE FRONT AND IS TRENDING A BIT FASTER AND SHOULD BE NEAR
THE COLORADO BORDER A FEW HOURS BEFORE MIDNIGHT. AFTER THE FRONT
AND ASSOCIATED TROUGH AXIS ALOFT MOVES THROUGH...WINDS WILL SHIFT
INTO THE NORTHWEST WHICH WILL END THE HIGH WIND EVENT BRIEFLY FOR
THE WIND PRONE AREAS AS WELL. HOWEVER...HIGH WINDS WILL LIKELY
RETURN BY LATE MONDAY NIGHT ACROSS MOST OF SOUTHEAST WYOMING.

SNOW WILL BE ANOTHER CONCERN...PRIMARILY ACROSS THE MOUNTAINS OF
SOUTHEAST WYOMING AND PERHAPS EVEN SOME OF THE HIGH VALLEYS. SNOW
IS DEVELOPING ACROSS THE MOUNTAINS EARLY THIS AFTERNOON WITH SOME
RAIN/SNOW MIX DOWN TO THE VALLEY FLOORS. ANY RAINFALL WILL QUICKLY
CHANGE TO SNOW LATE THIS AFTERNOON AS MUCH COLDER AIR MOVES INTO
THE AREA. THE HEAVIEST SNOW WILL BE TONIGHT...BUT ANOTHER
DISTURBANCE ALOFT WILL PUSH ACROSS THE AREA ON SUNDAY AS WELL
RESULTING IN SOME ENHANCEMENT OF SNOWFALL RATES. HIGH CONFIDENCE
THAT THE MOUNTAINS WILL DO WELL WITH THIS EVENT...SO KEPT THE
WINTER STORM WARNING GOING THROUGH MONDAY FOR 1 TO 2 FEET OF SNOW.
EXPECT THE PRECIPITATION TO BE ENHANCED FURTHER ON THE WEST TO
NORTHWEST FACING SLOPES AND RIDGES DUE TO UPSLOPE FLOW. FOR THE
VALLEYS AND HIGH PLAINS...EXPECT PERHAPS 1 TO 2 INCHES ALONG I80
WEST OF THE LARAMIE RANGE AND FURTHER NORTH ALONG I80 AROUND
DOUGLAS. THE CHEYENNE RIDGE FROM CHEYENNE TO SIDNEY INCLUDING MOST
OF THE NEBRASKA PANHANDLE WILL BE LUCKY TO SEE A DUSTING OF SNOW
DUE TO THE LARGE LOW LEVEL DOWNSLOPE COMPONENT TO THE WINDS. THE
BEST CHANCE TO SEE SOME SNOW WILL BE NEAR THE FRONTAL PASSAGE DUE
TO BRIEF FRONTOGENESIS AND LOW LEVEL DYNAMIC LIFT. THERE IS SOME
CONCERN THAT THE ADJACENT VALLEYS ACROSS SOUTHERN CARBON COUNTY
WILL SEE SOME MODERATE SNOWFALL RATES AS THE WINDS SHIFT INTO THE
NORTHWEST. WILL CONTINUE TO KEEP AN EYE ON THIS THROUGH SUNDAY AS
THE NEXT DISTURBANCE MOVES ACROSS THE AREA. FOR NOW...KEPT 1 TO 3
INCHES OF SNOW IN THESE LOCATIONS WITH 5 INCHES POSSIBLE LOCALLY.

FOR MONDAY...ANOTHER DISTURBANCE ALOFT WILL MOVE ACROSS THE
AREA...RESULTING IN ENHANCED SNOWFALL RATES ACROSS THE MOUNTAINS
AFTER A BRIEF LULL SUNDAY NIGHT. THIS MAY BE THE BEST CHANCE FOR
THE HIGH PLAINS TO RECEIVE SOME WIDESPREAD LIGHT SNOW
ACCUMULATIONS AS WINDS SHIFT INTO THE NORTH.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 300 PM MST SAT NOV 22 2014

STRONG WINDS CONTINUE THROUGH AT LEAST WEDNESDAY. GFS SHOWING A
1041MB SURFACE HIGH OVER WESTERN COLORADO TUESDAY MORNING WITH
A ROUGHLY 10-12MB SURFACE GRADIENT BETWEEN CASPER AND CRAIG.
700MB WINDS FROM THE NORTHWEST AT 50-60KTS WITH A 700MB HEIGHT
GRADIENT AROUND 70 TO 80 MARS BETWEEN CRAIG AND CASPER. ALMOST A
SURE THING FOR WIND WARNING CRITERIA AT LEAST FOR THE WIND PRONE
AREAS AND HAVE BUMPED UP GUIDANCE AT THESE LOCATIONS TO REFLECT
CONFIDENCE IN HIGH WINDS.

WINDS LOOK TO FINALLY EASE SOME THURSDAY AS WE SEE A FRONT DIVE
SOUTHWEST OUT OF THE DAKOTAS AND LAY UP AGAINST THE LARAMIE RANGE.
ECMWF A LITTLE FURTHER NORTHEAST WITH THIS FRONT OVER THE MORE
AGGRESSIVE GFS...FINALLY PUSHING THE BOUNDARY INTO THE LARAMIE
RANGE THURSDAY EVENING. DID GO AHEAD AND LOWER TEMPERATURES SOME
OVER THE NORTHERN PANHANDLE AND OUR EASTERN ZONES TO REFLECT THE
MUCH COLDER AIR BEHIND THE FRONT FOR THURSDAY THROUGH FRIDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 453 PM MST SAT NOV 22 2014

STRONG AND GUSTY WESTERLY WINDS WILL CONTINUE TONIGHT WITH THE
PASSAGE OF A PACIFIC COLD FRONT. GUSTS TO 50 KT WILL STILL BE
POSSIBLE EARLY THIS EVENING...MAINLY INVOF THE MOUNTAINS. GUSTS
WILL DECREASE TO 30-40 KT LATER THIS EVENING AND OVERNIGHT. MVFR
CONDITIONS IN RAIN/SNOW SHOWERS WEST OF THE LARAMIE RANGE WILL
SPREAD EAST ONTO THE PLAINS TONIGHT...WITH OCCASIONAL IFR POSSIBLE.
PRECIPITATION WILL TAPER OFF WITH IMPROVING CIGS/VSBYS SUNDAY
MORNING.

&&

.FIRE WEATHER...
ISSUED AT 209 PM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG THROUGH EARLY NEXT WEEK...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED DUE TO COOL TEMPERATURES AND HIGH
RELATIVE HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ112-114.

NE...WIND ADVISORY FROM 9 AM TO 6 PM MST SUNDAY FOR NEZ002-003-
     019>021-054-055-095-096.

&&

$$

UPDATE...MJ
SHORT TERM...TJT
LONG TERM...GCC
AVIATION...MJ
FIRE WEATHER...TJT



000
FXUS65 KCYS 230437
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
935 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 932 PM MST SAT NOV 22 2014

WINDS PER SURFACE/HIGHWAY OBSERVATIONS THE PAST FEW HOURS HAVE
SHOWN A GRADUAL DECREASING TREND...AND THE THREAT FOR HIGH WINDS
TONIGHT HAS ENDED. THUS HAVE CANCELLED HIGH WIND WARNINGS. COLD
FRONT HAS MOVED THROUGH RIVERTON AND CASPER AND WILL CONTINUE ITS
STEADY SOUTHEASTWARD PROGRESS THROUGH THE CWA TONIGHT. GUSTY
NORTHWEST WINDS OF 35 TO 45 MPH WILL OCCUR BEHIND THE FRONT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM MST SAT NOV 22 2014

PRIMARY CONCERNS THROUGH THIS WEEKEND WILL BE WINDS AND MOUNTAIN
SNOWFALL. MOST OF THE AREA WITHIN THE HIGH WIND WARNING HAS
VERIFIED THIS AFTERNOON WITH GUSTS AS HIGH AS 76 MPH REPORTED
ALONG I25 AND I80. ELSEWHERE...WINDS HAVE STRUGGLED ACROSS
LOCATIONS SUCH AS THE LARAMIE VALLEY AND THE HIGH PLAINS
IMMEDIATELY EAST OF THE LARAMIE RANGE. BELIEVE THIS IS DUE TO A
COMBINATION OF CLOUDY SKIES AND AN AREA OF POSITIVE OMEGA EAST OF
THE MOUNTAINS. WILL KEEP THE HIGH WIND WARNING OUT FOR THESE
AREAS...BUT THERE IS ONLY A SMALL WINDOW TO SEE GUSTS AROUND 55
MPH SINCE DOWNSLOPE AND SUBSIDENCE WILL BEGIN TO DIMINISH BY LATE
THIS EVENING. ENDED THE HIGH WIND WARNING AT MIDNIGHT TONIGHT
SINCE THE FRONT AND IS TRENDING A BIT FASTER AND SHOULD BE NEAR
THE COLORADO BORDER A FEW HOURS BEFORE MIDNIGHT. AFTER THE FRONT
AND ASSOCIATED TROUGH AXIS ALOFT MOVES THROUGH...WINDS WILL SHIFT
INTO THE NORTHWEST WHICH WILL END THE HIGH WIND EVENT BRIEFLY FOR
THE WIND PRONE AREAS AS WELL. HOWEVER...HIGH WINDS WILL LIKELY
RETURN BY LATE MONDAY NIGHT ACROSS MOST OF SOUTHEAST WYOMING.

SNOW WILL BE ANOTHER CONCERN...PRIMARILY ACROSS THE MOUNTAINS OF
SOUTHEAST WYOMING AND PERHAPS EVEN SOME OF THE HIGH VALLEYS. SNOW
IS DEVELOPING ACROSS THE MOUNTAINS EARLY THIS AFTERNOON WITH SOME
RAIN/SNOW MIX DOWN TO THE VALLEY FLOORS. ANY RAINFALL WILL QUICKLY
CHANGE TO SNOW LATE THIS AFTERNOON AS MUCH COLDER AIR MOVES INTO
THE AREA. THE HEAVIEST SNOW WILL BE TONIGHT...BUT ANOTHER
DISTURBANCE ALOFT WILL PUSH ACROSS THE AREA ON SUNDAY AS WELL
RESULTING IN SOME ENHANCEMENT OF SNOWFALL RATES. HIGH CONFIDENCE
THAT THE MOUNTAINS WILL DO WELL WITH THIS EVENT...SO KEPT THE
WINTER STORM WARNING GOING THROUGH MONDAY FOR 1 TO 2 FEET OF SNOW.
EXPECT THE PRECIPITATION TO BE ENHANCED FURTHER ON THE WEST TO
NORTHWEST FACING SLOPES AND RIDGES DUE TO UPSLOPE FLOW. FOR THE
VALLEYS AND HIGH PLAINS...EXPECT PERHAPS 1 TO 2 INCHES ALONG I80
WEST OF THE LARAMIE RANGE AND FURTHER NORTH ALONG I80 AROUND
DOUGLAS. THE CHEYENNE RIDGE FROM CHEYENNE TO SIDNEY INCLUDING MOST
OF THE NEBRASKA PANHANDLE WILL BE LUCKY TO SEE A DUSTING OF SNOW
DUE TO THE LARGE LOW LEVEL DOWNSLOPE COMPONENT TO THE WINDS. THE
BEST CHANCE TO SEE SOME SNOW WILL BE NEAR THE FRONTAL PASSAGE DUE
TO BRIEF FRONTOGENESIS AND LOW LEVEL DYNAMIC LIFT. THERE IS SOME
CONCERN THAT THE ADJACENT VALLEYS ACROSS SOUTHERN CARBON COUNTY
WILL SEE SOME MODERATE SNOWFALL RATES AS THE WINDS SHIFT INTO THE
NORTHWEST. WILL CONTINUE TO KEEP AN EYE ON THIS THROUGH SUNDAY AS
THE NEXT DISTURBANCE MOVES ACROSS THE AREA. FOR NOW...KEPT 1 TO 3
INCHES OF SNOW IN THESE LOCATIONS WITH 5 INCHES POSSIBLE LOCALLY.

FOR MONDAY...ANOTHER DISTURBANCE ALOFT WILL MOVE ACROSS THE
AREA...RESULTING IN ENHANCED SNOWFALL RATES ACROSS THE MOUNTAINS
AFTER A BRIEF LULL SUNDAY NIGHT. THIS MAY BE THE BEST CHANCE FOR
THE HIGH PLAINS TO RECEIVE SOME WIDESPREAD LIGHT SNOW
ACCUMULATIONS AS WINDS SHIFT INTO THE NORTH.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 300 PM MST SAT NOV 22 2014

STRONG WINDS CONTINUE THROUGH AT LEAST WEDNESDAY. GFS SHOWING A
1041MB SURFACE HIGH OVER WESTERN COLORADO TUESDAY MORNING WITH
A ROUGHLY 10-12MB SURFACE GRADIENT BETWEEN CASPER AND CRAIG.
700MB WINDS FROM THE NORTHWEST AT 50-60KTS WITH A 700MB HEIGHT
GRADIENT AROUND 70 TO 80 MARS BETWEEN CRAIG AND CASPER. ALMOST A
SURE THING FOR WIND WARNING CRITERIA AT LEAST FOR THE WIND PRONE
AREAS AND HAVE BUMPED UP GUIDANCE AT THESE LOCATIONS TO REFLECT
CONFIDENCE IN HIGH WINDS.

WINDS LOOK TO FINALLY EASE SOME THURSDAY AS WE SEE A FRONT DIVE
SOUTHWEST OUT OF THE DAKOTAS AND LAY UP AGAINST THE LARAMIE RANGE.
ECMWF A LITTLE FURTHER NORTHEAST WITH THIS FRONT OVER THE MORE
AGGRESSIVE GFS...FINALLY PUSHING THE BOUNDARY INTO THE LARAMIE
RANGE THURSDAY EVENING. DID GO AHEAD AND LOWER TEMPERATURES SOME
OVER THE NORTHERN PANHANDLE AND OUR EASTERN ZONES TO REFLECT THE
MUCH COLDER AIR BEHIND THE FRONT FOR THURSDAY THROUGH FRIDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 453 PM MST SAT NOV 22 2014

STRONG AND GUSTY WESTERLY WINDS WILL CONTINUE TONIGHT WITH THE
PASSAGE OF A PACIFIC COLD FRONT. GUSTS TO 50 KT WILL STILL BE
POSSIBLE EARLY THIS EVENING...MAINLY INVOF THE MOUNTAINS. GUSTS
WILL DECREASE TO 30-40 KT LATER THIS EVENING AND OVERNIGHT. MVFR
CONDITIONS IN RAIN/SNOW SHOWERS WEST OF THE LARAMIE RANGE WILL
SPREAD EAST ONTO THE PLAINS TONIGHT...WITH OCCASIONAL IFR POSSIBLE.
PRECIPITATION WILL TAPER OFF WITH IMPROVING CIGS/VSBYS SUNDAY
MORNING.

&&

.FIRE WEATHER...
ISSUED AT 209 PM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG THROUGH EARLY NEXT WEEK...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED DUE TO COOL TEMPERATURES AND HIGH
RELATIVE HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ112-114.

NE...WIND ADVISORY FROM 9 AM TO 6 PM MST SUNDAY FOR NEZ002-003-
     019>021-054-055-095-096.

&&

$$

UPDATE...MJ
SHORT TERM...TJT
LONG TERM...GCC
AVIATION...MJ
FIRE WEATHER...TJT




000
FXUS65 KCYS 230435
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
935 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 932 PM MST SAT NOV 22 2014

WINDS PER SURFACE/HIGHWAY OBSERVATIONS THE PAST FEW HOURS HAVE
SHOWN A GRADUAL DECREASING TREND...AND THE THREAT FOR HIGH WINDS
TONIGHT HAVE ENDED. THUS HAVE CANCELLED HIGH WIND WARNINGS. COLD
FRONT HAS MOVED THROUGH RIVERTON AND CASPER AND WILL CONTINUE
ITS STEADY SOUTHEASTWARD PROGRESS THROUGH THE CWA TONIGHT. GUSTY
NORTHWEST WINDS OF 35 TO 45 MPH WILL OCCUR BEHIND THE FRONT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM MST SAT NOV 22 2014

PRIMARY CONCERNS THROUGH THIS WEEKEND WILL BE WINDS AND MOUNTAIN
SNOWFALL. MOST OF THE AREA WITHIN THE HIGH WIND WARNING HAS
VERIFIED THIS AFTERNOON WITH GUSTS AS HIGH AS 76 MPH REPORTED
ALONG I25 AND I80. ELSEWHERE...WINDS HAVE STRUGGLED ACROSS
LOCATIONS SUCH AS THE LARAMIE VALLEY AND THE HIGH PLAINS
IMMEDIATELY EAST OF THE LARAMIE RANGE. BELIEVE THIS IS DUE TO A
COMBINATION OF CLOUDY SKIES AND AN AREA OF POSITIVE OMEGA EAST OF
THE MOUNTAINS. WILL KEEP THE HIGH WIND WARNING OUT FOR THESE
AREAS...BUT THERE IS ONLY A SMALL WINDOW TO SEE GUSTS AROUND 55
MPH SINCE DOWNSLOPE AND SUBSIDENCE WILL BEGIN TO DIMINISH BY LATE
THIS EVENING. ENDED THE HIGH WIND WARNING AT MIDNIGHT TONIGHT
SINCE THE FRONT AND IS TRENDING A BIT FASTER AND SHOULD BE NEAR
THE COLORADO BORDER A FEW HOURS BEFORE MIDNIGHT. AFTER THE FRONT
AND ASSOCIATED TROUGH AXIS ALOFT MOVES THROUGH...WINDS WILL SHIFT
INTO THE NORTHWEST WHICH WILL END THE HIGH WIND EVENT BRIEFLY FOR
THE WIND PRONE AREAS AS WELL. HOWEVER...HIGH WINDS WILL LIKELY
RETURN BY LATE MONDAY NIGHT ACROSS MOST OF SOUTHEAST WYOMING.

SNOW WILL BE ANOTHER CONCERN...PRIMARILY ACROSS THE MOUNTAINS OF
SOUTHEAST WYOMING AND PERHAPS EVEN SOME OF THE HIGH VALLEYS. SNOW
IS DEVELOPING ACROSS THE MOUNTAINS EARLY THIS AFTERNOON WITH SOME
RAIN/SNOW MIX DOWN TO THE VALLEY FLOORS. ANY RAINFALL WILL QUICKLY
CHANGE TO SNOW LATE THIS AFTERNOON AS MUCH COLDER AIR MOVES INTO
THE AREA. THE HEAVIEST SNOW WILL BE TONIGHT...BUT ANOTHER
DISTURBANCE ALOFT WILL PUSH ACROSS THE AREA ON SUNDAY AS WELL
RESULTING IN SOME ENHANCEMENT OF SNOWFALL RATES. HIGH CONFIDENCE
THAT THE MOUNTAINS WILL DO WELL WITH THIS EVENT...SO KEPT THE
WINTER STORM WARNING GOING THROUGH MONDAY FOR 1 TO 2 FEET OF SNOW.
EXPECT THE PRECIPITATION TO BE ENHANCED FURTHER ON THE WEST TO
NORTHWEST FACING SLOPES AND RIDGES DUE TO UPSLOPE FLOW. FOR THE
VALLEYS AND HIGH PLAINS...EXPECT PERHAPS 1 TO 2 INCHES ALONG I80
WEST OF THE LARAMIE RANGE AND FURTHER NORTH ALONG I80 AROUND
DOUGLAS. THE CHEYENNE RIDGE FROM CHEYENNE TO SIDNEY INCLUDING MOST
OF THE NEBRASKA PANHANDLE WILL BE LUCKY TO SEE A DUSTING OF SNOW
DUE TO THE LARGE LOW LEVEL DOWNSLOPE COMPONENT TO THE WINDS. THE
BEST CHANCE TO SEE SOME SNOW WILL BE NEAR THE FRONTAL PASSAGE DUE
TO BRIEF FRONTOGENESIS AND LOW LEVEL DYNAMIC LIFT. THERE IS SOME
CONCERN THAT THE ADJACENT VALLEYS ACROSS SOUTHERN CARBON COUNTY
WILL SEE SOME MODERATE SNOWFALL RATES AS THE WINDS SHIFT INTO THE
NORTHWEST. WILL CONTINUE TO KEEP AN EYE ON THIS THROUGH SUNDAY AS
THE NEXT DISTURBANCE MOVES ACROSS THE AREA. FOR NOW...KEPT 1 TO 3
INCHES OF SNOW IN THESE LOCATIONS WITH 5 INCHES POSSIBLE LOCALLY.

FOR MONDAY...ANOTHER DISTURBANCE ALOFT WILL MOVE ACROSS THE
AREA...RESULTING IN ENHANCED SNOWFALL RATES ACROSS THE MOUNTAINS
AFTER A BRIEF LULL SUNDAY NIGHT. THIS MAY BE THE BEST CHANCE FOR
THE HIGH PLAINS TO RECEIVE SOME WIDESPREAD LIGHT SNOW
ACCUMULATIONS AS WINDS SHIFT INTO THE NORTH.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 300 PM MST SAT NOV 22 2014

STRONG WINDS CONTINUE THROUGH AT LEAST WEDNESDAY. GFS SHOWING A
1041MB SURFACE HIGH OVER WESTERN COLORADO TUESDAY MORNING WITH
A ROUGHLY 10-12MB SURFACE GRADIENT BETWEEN CASPER AND CRAIG.
700MB WINDS FROM THE NORTHWEST AT 50-60KTS WITH A 700MB HEIGHT
GRADIENT AROUND 70 TO 80 MARS BETWEEN CRAIG AND CASPER. ALMOST A
SURE THING FOR WIND WARNING CRITERIA AT LEAST FOR THE WIND PRONE
AREAS AND HAVE BUMPED UP GUIDANCE AT THESE LOCATIONS TO REFLECT
CONFIDENCE IN HIGH WINDS.

WINDS LOOK TO FINALLY EASE SOME THURSDAY AS WE SEE A FRONT DIVE
SOUTHWEST OUT OF THE DAKOTAS AND LAY UP AGAINST THE LARAMIE RANGE.
ECMWF A LITTLE FURTHER NORTHEAST WITH THIS FRONT OVER THE MORE
AGGRESSIVE GFS...FINALLY PUSHING THE BOUNDARY INTO THE LARAMIE
RANGE THURSDAY EVENING. DID GO AHEAD AND LOWER TEMPERATURES SOME
OVER THE NORTHERN PANHANDLE AND OUR EASTERN ZONES TO REFLECT THE
MUCH COLDER AIR BEHIND THE FRONT FOR THURSDAY THROUGH FRIDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 453 PM MST SAT NOV 22 2014

STRONG AND GUSTY WESTERLY WINDS WILL CONTINUE TONIGHT WITH THE
PASSAGE OF A PACIFIC COLD FRONT. GUSTS TO 50 KT WILL STILL BE
POSSIBLE EARLY THIS EVENING...MAINLY INVOF THE MOUNTAINS. GUSTS
WILL DECREASE TO 30-40 KT LATER THIS EVENING AND OVERNIGHT. MVFR
CONDITIONS IN RAIN/SNOW SHOWERS WEST OF THE LARAMIE RANGE WILL
SPREAD EAST ONTO THE PLAINS TONIGHT...WITH OCCASIONAL IFR POSSIBLE.
PRECIPITATION WILL TAPER OFF WITH IMPROVING CIGS/VSBYS SUNDAY
MORNING.

&&

.FIRE WEATHER...
ISSUED AT 209 PM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG THROUGH EARLY NEXT WEEK...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED DUE TO COOL TEMPERATURES AND HIGH
RELATIVE HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ112-114.

NE...WIND ADVISORY FROM 9 AM TO 6 PM MST SUNDAY FOR NEZ002-003-
     019>021-054-055-095-096.

&&

$$

UPDATE...MJ
SHORT TERM...TJT
LONG TERM...GCC
AVIATION...MJ
FIRE WEATHER...TJT




000
FXUS65 KCYS 230435
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
935 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 932 PM MST SAT NOV 22 2014

WINDS PER SURFACE/HIGHWAY OBSERVATIONS THE PAST FEW HOURS HAVE
SHOWN A GRADUAL DECREASING TREND...AND THE THREAT FOR HIGH WINDS
TONIGHT HAVE ENDED. THUS HAVE CANCELLED HIGH WIND WARNINGS. COLD
FRONT HAS MOVED THROUGH RIVERTON AND CASPER AND WILL CONTINUE
ITS STEADY SOUTHEASTWARD PROGRESS THROUGH THE CWA TONIGHT. GUSTY
NORTHWEST WINDS OF 35 TO 45 MPH WILL OCCUR BEHIND THE FRONT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM MST SAT NOV 22 2014

PRIMARY CONCERNS THROUGH THIS WEEKEND WILL BE WINDS AND MOUNTAIN
SNOWFALL. MOST OF THE AREA WITHIN THE HIGH WIND WARNING HAS
VERIFIED THIS AFTERNOON WITH GUSTS AS HIGH AS 76 MPH REPORTED
ALONG I25 AND I80. ELSEWHERE...WINDS HAVE STRUGGLED ACROSS
LOCATIONS SUCH AS THE LARAMIE VALLEY AND THE HIGH PLAINS
IMMEDIATELY EAST OF THE LARAMIE RANGE. BELIEVE THIS IS DUE TO A
COMBINATION OF CLOUDY SKIES AND AN AREA OF POSITIVE OMEGA EAST OF
THE MOUNTAINS. WILL KEEP THE HIGH WIND WARNING OUT FOR THESE
AREAS...BUT THERE IS ONLY A SMALL WINDOW TO SEE GUSTS AROUND 55
MPH SINCE DOWNSLOPE AND SUBSIDENCE WILL BEGIN TO DIMINISH BY LATE
THIS EVENING. ENDED THE HIGH WIND WARNING AT MIDNIGHT TONIGHT
SINCE THE FRONT AND IS TRENDING A BIT FASTER AND SHOULD BE NEAR
THE COLORADO BORDER A FEW HOURS BEFORE MIDNIGHT. AFTER THE FRONT
AND ASSOCIATED TROUGH AXIS ALOFT MOVES THROUGH...WINDS WILL SHIFT
INTO THE NORTHWEST WHICH WILL END THE HIGH WIND EVENT BRIEFLY FOR
THE WIND PRONE AREAS AS WELL. HOWEVER...HIGH WINDS WILL LIKELY
RETURN BY LATE MONDAY NIGHT ACROSS MOST OF SOUTHEAST WYOMING.

SNOW WILL BE ANOTHER CONCERN...PRIMARILY ACROSS THE MOUNTAINS OF
SOUTHEAST WYOMING AND PERHAPS EVEN SOME OF THE HIGH VALLEYS. SNOW
IS DEVELOPING ACROSS THE MOUNTAINS EARLY THIS AFTERNOON WITH SOME
RAIN/SNOW MIX DOWN TO THE VALLEY FLOORS. ANY RAINFALL WILL QUICKLY
CHANGE TO SNOW LATE THIS AFTERNOON AS MUCH COLDER AIR MOVES INTO
THE AREA. THE HEAVIEST SNOW WILL BE TONIGHT...BUT ANOTHER
DISTURBANCE ALOFT WILL PUSH ACROSS THE AREA ON SUNDAY AS WELL
RESULTING IN SOME ENHANCEMENT OF SNOWFALL RATES. HIGH CONFIDENCE
THAT THE MOUNTAINS WILL DO WELL WITH THIS EVENT...SO KEPT THE
WINTER STORM WARNING GOING THROUGH MONDAY FOR 1 TO 2 FEET OF SNOW.
EXPECT THE PRECIPITATION TO BE ENHANCED FURTHER ON THE WEST TO
NORTHWEST FACING SLOPES AND RIDGES DUE TO UPSLOPE FLOW. FOR THE
VALLEYS AND HIGH PLAINS...EXPECT PERHAPS 1 TO 2 INCHES ALONG I80
WEST OF THE LARAMIE RANGE AND FURTHER NORTH ALONG I80 AROUND
DOUGLAS. THE CHEYENNE RIDGE FROM CHEYENNE TO SIDNEY INCLUDING MOST
OF THE NEBRASKA PANHANDLE WILL BE LUCKY TO SEE A DUSTING OF SNOW
DUE TO THE LARGE LOW LEVEL DOWNSLOPE COMPONENT TO THE WINDS. THE
BEST CHANCE TO SEE SOME SNOW WILL BE NEAR THE FRONTAL PASSAGE DUE
TO BRIEF FRONTOGENESIS AND LOW LEVEL DYNAMIC LIFT. THERE IS SOME
CONCERN THAT THE ADJACENT VALLEYS ACROSS SOUTHERN CARBON COUNTY
WILL SEE SOME MODERATE SNOWFALL RATES AS THE WINDS SHIFT INTO THE
NORTHWEST. WILL CONTINUE TO KEEP AN EYE ON THIS THROUGH SUNDAY AS
THE NEXT DISTURBANCE MOVES ACROSS THE AREA. FOR NOW...KEPT 1 TO 3
INCHES OF SNOW IN THESE LOCATIONS WITH 5 INCHES POSSIBLE LOCALLY.

FOR MONDAY...ANOTHER DISTURBANCE ALOFT WILL MOVE ACROSS THE
AREA...RESULTING IN ENHANCED SNOWFALL RATES ACROSS THE MOUNTAINS
AFTER A BRIEF LULL SUNDAY NIGHT. THIS MAY BE THE BEST CHANCE FOR
THE HIGH PLAINS TO RECEIVE SOME WIDESPREAD LIGHT SNOW
ACCUMULATIONS AS WINDS SHIFT INTO THE NORTH.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 300 PM MST SAT NOV 22 2014

STRONG WINDS CONTINUE THROUGH AT LEAST WEDNESDAY. GFS SHOWING A
1041MB SURFACE HIGH OVER WESTERN COLORADO TUESDAY MORNING WITH
A ROUGHLY 10-12MB SURFACE GRADIENT BETWEEN CASPER AND CRAIG.
700MB WINDS FROM THE NORTHWEST AT 50-60KTS WITH A 700MB HEIGHT
GRADIENT AROUND 70 TO 80 MARS BETWEEN CRAIG AND CASPER. ALMOST A
SURE THING FOR WIND WARNING CRITERIA AT LEAST FOR THE WIND PRONE
AREAS AND HAVE BUMPED UP GUIDANCE AT THESE LOCATIONS TO REFLECT
CONFIDENCE IN HIGH WINDS.

WINDS LOOK TO FINALLY EASE SOME THURSDAY AS WE SEE A FRONT DIVE
SOUTHWEST OUT OF THE DAKOTAS AND LAY UP AGAINST THE LARAMIE RANGE.
ECMWF A LITTLE FURTHER NORTHEAST WITH THIS FRONT OVER THE MORE
AGGRESSIVE GFS...FINALLY PUSHING THE BOUNDARY INTO THE LARAMIE
RANGE THURSDAY EVENING. DID GO AHEAD AND LOWER TEMPERATURES SOME
OVER THE NORTHERN PANHANDLE AND OUR EASTERN ZONES TO REFLECT THE
MUCH COLDER AIR BEHIND THE FRONT FOR THURSDAY THROUGH FRIDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 453 PM MST SAT NOV 22 2014

STRONG AND GUSTY WESTERLY WINDS WILL CONTINUE TONIGHT WITH THE
PASSAGE OF A PACIFIC COLD FRONT. GUSTS TO 50 KT WILL STILL BE
POSSIBLE EARLY THIS EVENING...MAINLY INVOF THE MOUNTAINS. GUSTS
WILL DECREASE TO 30-40 KT LATER THIS EVENING AND OVERNIGHT. MVFR
CONDITIONS IN RAIN/SNOW SHOWERS WEST OF THE LARAMIE RANGE WILL
SPREAD EAST ONTO THE PLAINS TONIGHT...WITH OCCASIONAL IFR POSSIBLE.
PRECIPITATION WILL TAPER OFF WITH IMPROVING CIGS/VSBYS SUNDAY
MORNING.

&&

.FIRE WEATHER...
ISSUED AT 209 PM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG THROUGH EARLY NEXT WEEK...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED DUE TO COOL TEMPERATURES AND HIGH
RELATIVE HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ112-114.

NE...WIND ADVISORY FROM 9 AM TO 6 PM MST SUNDAY FOR NEZ002-003-
     019>021-054-055-095-096.

&&

$$

UPDATE...MJ
SHORT TERM...TJT
LONG TERM...GCC
AVIATION...MJ
FIRE WEATHER...TJT




000
FXUS65 KCYS 230435
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
935 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 932 PM MST SAT NOV 22 2014

WINDS PER SURFACE/HIGHWAY OBSERVATIONS THE PAST FEW HOURS HAVE
SHOWN A GRADUAL DECREASING TREND...AND THE THREAT FOR HIGH WINDS
TONIGHT HAVE ENDED. THUS HAVE CANCELLED HIGH WIND WARNINGS. COLD
FRONT HAS MOVED THROUGH RIVERTON AND CASPER AND WILL CONTINUE
ITS STEADY SOUTHEASTWARD PROGRESS THROUGH THE CWA TONIGHT. GUSTY
NORTHWEST WINDS OF 35 TO 45 MPH WILL OCCUR BEHIND THE FRONT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM MST SAT NOV 22 2014

PRIMARY CONCERNS THROUGH THIS WEEKEND WILL BE WINDS AND MOUNTAIN
SNOWFALL. MOST OF THE AREA WITHIN THE HIGH WIND WARNING HAS
VERIFIED THIS AFTERNOON WITH GUSTS AS HIGH AS 76 MPH REPORTED
ALONG I25 AND I80. ELSEWHERE...WINDS HAVE STRUGGLED ACROSS
LOCATIONS SUCH AS THE LARAMIE VALLEY AND THE HIGH PLAINS
IMMEDIATELY EAST OF THE LARAMIE RANGE. BELIEVE THIS IS DUE TO A
COMBINATION OF CLOUDY SKIES AND AN AREA OF POSITIVE OMEGA EAST OF
THE MOUNTAINS. WILL KEEP THE HIGH WIND WARNING OUT FOR THESE
AREAS...BUT THERE IS ONLY A SMALL WINDOW TO SEE GUSTS AROUND 55
MPH SINCE DOWNSLOPE AND SUBSIDENCE WILL BEGIN TO DIMINISH BY LATE
THIS EVENING. ENDED THE HIGH WIND WARNING AT MIDNIGHT TONIGHT
SINCE THE FRONT AND IS TRENDING A BIT FASTER AND SHOULD BE NEAR
THE COLORADO BORDER A FEW HOURS BEFORE MIDNIGHT. AFTER THE FRONT
AND ASSOCIATED TROUGH AXIS ALOFT MOVES THROUGH...WINDS WILL SHIFT
INTO THE NORTHWEST WHICH WILL END THE HIGH WIND EVENT BRIEFLY FOR
THE WIND PRONE AREAS AS WELL. HOWEVER...HIGH WINDS WILL LIKELY
RETURN BY LATE MONDAY NIGHT ACROSS MOST OF SOUTHEAST WYOMING.

SNOW WILL BE ANOTHER CONCERN...PRIMARILY ACROSS THE MOUNTAINS OF
SOUTHEAST WYOMING AND PERHAPS EVEN SOME OF THE HIGH VALLEYS. SNOW
IS DEVELOPING ACROSS THE MOUNTAINS EARLY THIS AFTERNOON WITH SOME
RAIN/SNOW MIX DOWN TO THE VALLEY FLOORS. ANY RAINFALL WILL QUICKLY
CHANGE TO SNOW LATE THIS AFTERNOON AS MUCH COLDER AIR MOVES INTO
THE AREA. THE HEAVIEST SNOW WILL BE TONIGHT...BUT ANOTHER
DISTURBANCE ALOFT WILL PUSH ACROSS THE AREA ON SUNDAY AS WELL
RESULTING IN SOME ENHANCEMENT OF SNOWFALL RATES. HIGH CONFIDENCE
THAT THE MOUNTAINS WILL DO WELL WITH THIS EVENT...SO KEPT THE
WINTER STORM WARNING GOING THROUGH MONDAY FOR 1 TO 2 FEET OF SNOW.
EXPECT THE PRECIPITATION TO BE ENHANCED FURTHER ON THE WEST TO
NORTHWEST FACING SLOPES AND RIDGES DUE TO UPSLOPE FLOW. FOR THE
VALLEYS AND HIGH PLAINS...EXPECT PERHAPS 1 TO 2 INCHES ALONG I80
WEST OF THE LARAMIE RANGE AND FURTHER NORTH ALONG I80 AROUND
DOUGLAS. THE CHEYENNE RIDGE FROM CHEYENNE TO SIDNEY INCLUDING MOST
OF THE NEBRASKA PANHANDLE WILL BE LUCKY TO SEE A DUSTING OF SNOW
DUE TO THE LARGE LOW LEVEL DOWNSLOPE COMPONENT TO THE WINDS. THE
BEST CHANCE TO SEE SOME SNOW WILL BE NEAR THE FRONTAL PASSAGE DUE
TO BRIEF FRONTOGENESIS AND LOW LEVEL DYNAMIC LIFT. THERE IS SOME
CONCERN THAT THE ADJACENT VALLEYS ACROSS SOUTHERN CARBON COUNTY
WILL SEE SOME MODERATE SNOWFALL RATES AS THE WINDS SHIFT INTO THE
NORTHWEST. WILL CONTINUE TO KEEP AN EYE ON THIS THROUGH SUNDAY AS
THE NEXT DISTURBANCE MOVES ACROSS THE AREA. FOR NOW...KEPT 1 TO 3
INCHES OF SNOW IN THESE LOCATIONS WITH 5 INCHES POSSIBLE LOCALLY.

FOR MONDAY...ANOTHER DISTURBANCE ALOFT WILL MOVE ACROSS THE
AREA...RESULTING IN ENHANCED SNOWFALL RATES ACROSS THE MOUNTAINS
AFTER A BRIEF LULL SUNDAY NIGHT. THIS MAY BE THE BEST CHANCE FOR
THE HIGH PLAINS TO RECEIVE SOME WIDESPREAD LIGHT SNOW
ACCUMULATIONS AS WINDS SHIFT INTO THE NORTH.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 300 PM MST SAT NOV 22 2014

STRONG WINDS CONTINUE THROUGH AT LEAST WEDNESDAY. GFS SHOWING A
1041MB SURFACE HIGH OVER WESTERN COLORADO TUESDAY MORNING WITH
A ROUGHLY 10-12MB SURFACE GRADIENT BETWEEN CASPER AND CRAIG.
700MB WINDS FROM THE NORTHWEST AT 50-60KTS WITH A 700MB HEIGHT
GRADIENT AROUND 70 TO 80 MARS BETWEEN CRAIG AND CASPER. ALMOST A
SURE THING FOR WIND WARNING CRITERIA AT LEAST FOR THE WIND PRONE
AREAS AND HAVE BUMPED UP GUIDANCE AT THESE LOCATIONS TO REFLECT
CONFIDENCE IN HIGH WINDS.

WINDS LOOK TO FINALLY EASE SOME THURSDAY AS WE SEE A FRONT DIVE
SOUTHWEST OUT OF THE DAKOTAS AND LAY UP AGAINST THE LARAMIE RANGE.
ECMWF A LITTLE FURTHER NORTHEAST WITH THIS FRONT OVER THE MORE
AGGRESSIVE GFS...FINALLY PUSHING THE BOUNDARY INTO THE LARAMIE
RANGE THURSDAY EVENING. DID GO AHEAD AND LOWER TEMPERATURES SOME
OVER THE NORTHERN PANHANDLE AND OUR EASTERN ZONES TO REFLECT THE
MUCH COLDER AIR BEHIND THE FRONT FOR THURSDAY THROUGH FRIDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 453 PM MST SAT NOV 22 2014

STRONG AND GUSTY WESTERLY WINDS WILL CONTINUE TONIGHT WITH THE
PASSAGE OF A PACIFIC COLD FRONT. GUSTS TO 50 KT WILL STILL BE
POSSIBLE EARLY THIS EVENING...MAINLY INVOF THE MOUNTAINS. GUSTS
WILL DECREASE TO 30-40 KT LATER THIS EVENING AND OVERNIGHT. MVFR
CONDITIONS IN RAIN/SNOW SHOWERS WEST OF THE LARAMIE RANGE WILL
SPREAD EAST ONTO THE PLAINS TONIGHT...WITH OCCASIONAL IFR POSSIBLE.
PRECIPITATION WILL TAPER OFF WITH IMPROVING CIGS/VSBYS SUNDAY
MORNING.

&&

.FIRE WEATHER...
ISSUED AT 209 PM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG THROUGH EARLY NEXT WEEK...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED DUE TO COOL TEMPERATURES AND HIGH
RELATIVE HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ112-114.

NE...WIND ADVISORY FROM 9 AM TO 6 PM MST SUNDAY FOR NEZ002-003-
     019>021-054-055-095-096.

&&

$$

UPDATE...MJ
SHORT TERM...TJT
LONG TERM...GCC
AVIATION...MJ
FIRE WEATHER...TJT




000
FXUS65 KCYS 230435
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
935 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 932 PM MST SAT NOV 22 2014

WINDS PER SURFACE/HIGHWAY OBSERVATIONS THE PAST FEW HOURS HAVE
SHOWN A GRADUAL DECREASING TREND...AND THE THREAT FOR HIGH WINDS
TONIGHT HAVE ENDED. THUS HAVE CANCELLED HIGH WIND WARNINGS. COLD
FRONT HAS MOVED THROUGH RIVERTON AND CASPER AND WILL CONTINUE
ITS STEADY SOUTHEASTWARD PROGRESS THROUGH THE CWA TONIGHT. GUSTY
NORTHWEST WINDS OF 35 TO 45 MPH WILL OCCUR BEHIND THE FRONT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM MST SAT NOV 22 2014

PRIMARY CONCERNS THROUGH THIS WEEKEND WILL BE WINDS AND MOUNTAIN
SNOWFALL. MOST OF THE AREA WITHIN THE HIGH WIND WARNING HAS
VERIFIED THIS AFTERNOON WITH GUSTS AS HIGH AS 76 MPH REPORTED
ALONG I25 AND I80. ELSEWHERE...WINDS HAVE STRUGGLED ACROSS
LOCATIONS SUCH AS THE LARAMIE VALLEY AND THE HIGH PLAINS
IMMEDIATELY EAST OF THE LARAMIE RANGE. BELIEVE THIS IS DUE TO A
COMBINATION OF CLOUDY SKIES AND AN AREA OF POSITIVE OMEGA EAST OF
THE MOUNTAINS. WILL KEEP THE HIGH WIND WARNING OUT FOR THESE
AREAS...BUT THERE IS ONLY A SMALL WINDOW TO SEE GUSTS AROUND 55
MPH SINCE DOWNSLOPE AND SUBSIDENCE WILL BEGIN TO DIMINISH BY LATE
THIS EVENING. ENDED THE HIGH WIND WARNING AT MIDNIGHT TONIGHT
SINCE THE FRONT AND IS TRENDING A BIT FASTER AND SHOULD BE NEAR
THE COLORADO BORDER A FEW HOURS BEFORE MIDNIGHT. AFTER THE FRONT
AND ASSOCIATED TROUGH AXIS ALOFT MOVES THROUGH...WINDS WILL SHIFT
INTO THE NORTHWEST WHICH WILL END THE HIGH WIND EVENT BRIEFLY FOR
THE WIND PRONE AREAS AS WELL. HOWEVER...HIGH WINDS WILL LIKELY
RETURN BY LATE MONDAY NIGHT ACROSS MOST OF SOUTHEAST WYOMING.

SNOW WILL BE ANOTHER CONCERN...PRIMARILY ACROSS THE MOUNTAINS OF
SOUTHEAST WYOMING AND PERHAPS EVEN SOME OF THE HIGH VALLEYS. SNOW
IS DEVELOPING ACROSS THE MOUNTAINS EARLY THIS AFTERNOON WITH SOME
RAIN/SNOW MIX DOWN TO THE VALLEY FLOORS. ANY RAINFALL WILL QUICKLY
CHANGE TO SNOW LATE THIS AFTERNOON AS MUCH COLDER AIR MOVES INTO
THE AREA. THE HEAVIEST SNOW WILL BE TONIGHT...BUT ANOTHER
DISTURBANCE ALOFT WILL PUSH ACROSS THE AREA ON SUNDAY AS WELL
RESULTING IN SOME ENHANCEMENT OF SNOWFALL RATES. HIGH CONFIDENCE
THAT THE MOUNTAINS WILL DO WELL WITH THIS EVENT...SO KEPT THE
WINTER STORM WARNING GOING THROUGH MONDAY FOR 1 TO 2 FEET OF SNOW.
EXPECT THE PRECIPITATION TO BE ENHANCED FURTHER ON THE WEST TO
NORTHWEST FACING SLOPES AND RIDGES DUE TO UPSLOPE FLOW. FOR THE
VALLEYS AND HIGH PLAINS...EXPECT PERHAPS 1 TO 2 INCHES ALONG I80
WEST OF THE LARAMIE RANGE AND FURTHER NORTH ALONG I80 AROUND
DOUGLAS. THE CHEYENNE RIDGE FROM CHEYENNE TO SIDNEY INCLUDING MOST
OF THE NEBRASKA PANHANDLE WILL BE LUCKY TO SEE A DUSTING OF SNOW
DUE TO THE LARGE LOW LEVEL DOWNSLOPE COMPONENT TO THE WINDS. THE
BEST CHANCE TO SEE SOME SNOW WILL BE NEAR THE FRONTAL PASSAGE DUE
TO BRIEF FRONTOGENESIS AND LOW LEVEL DYNAMIC LIFT. THERE IS SOME
CONCERN THAT THE ADJACENT VALLEYS ACROSS SOUTHERN CARBON COUNTY
WILL SEE SOME MODERATE SNOWFALL RATES AS THE WINDS SHIFT INTO THE
NORTHWEST. WILL CONTINUE TO KEEP AN EYE ON THIS THROUGH SUNDAY AS
THE NEXT DISTURBANCE MOVES ACROSS THE AREA. FOR NOW...KEPT 1 TO 3
INCHES OF SNOW IN THESE LOCATIONS WITH 5 INCHES POSSIBLE LOCALLY.

FOR MONDAY...ANOTHER DISTURBANCE ALOFT WILL MOVE ACROSS THE
AREA...RESULTING IN ENHANCED SNOWFALL RATES ACROSS THE MOUNTAINS
AFTER A BRIEF LULL SUNDAY NIGHT. THIS MAY BE THE BEST CHANCE FOR
THE HIGH PLAINS TO RECEIVE SOME WIDESPREAD LIGHT SNOW
ACCUMULATIONS AS WINDS SHIFT INTO THE NORTH.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 300 PM MST SAT NOV 22 2014

STRONG WINDS CONTINUE THROUGH AT LEAST WEDNESDAY. GFS SHOWING A
1041MB SURFACE HIGH OVER WESTERN COLORADO TUESDAY MORNING WITH
A ROUGHLY 10-12MB SURFACE GRADIENT BETWEEN CASPER AND CRAIG.
700MB WINDS FROM THE NORTHWEST AT 50-60KTS WITH A 700MB HEIGHT
GRADIENT AROUND 70 TO 80 MARS BETWEEN CRAIG AND CASPER. ALMOST A
SURE THING FOR WIND WARNING CRITERIA AT LEAST FOR THE WIND PRONE
AREAS AND HAVE BUMPED UP GUIDANCE AT THESE LOCATIONS TO REFLECT
CONFIDENCE IN HIGH WINDS.

WINDS LOOK TO FINALLY EASE SOME THURSDAY AS WE SEE A FRONT DIVE
SOUTHWEST OUT OF THE DAKOTAS AND LAY UP AGAINST THE LARAMIE RANGE.
ECMWF A LITTLE FURTHER NORTHEAST WITH THIS FRONT OVER THE MORE
AGGRESSIVE GFS...FINALLY PUSHING THE BOUNDARY INTO THE LARAMIE
RANGE THURSDAY EVENING. DID GO AHEAD AND LOWER TEMPERATURES SOME
OVER THE NORTHERN PANHANDLE AND OUR EASTERN ZONES TO REFLECT THE
MUCH COLDER AIR BEHIND THE FRONT FOR THURSDAY THROUGH FRIDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 453 PM MST SAT NOV 22 2014

STRONG AND GUSTY WESTERLY WINDS WILL CONTINUE TONIGHT WITH THE
PASSAGE OF A PACIFIC COLD FRONT. GUSTS TO 50 KT WILL STILL BE
POSSIBLE EARLY THIS EVENING...MAINLY INVOF THE MOUNTAINS. GUSTS
WILL DECREASE TO 30-40 KT LATER THIS EVENING AND OVERNIGHT. MVFR
CONDITIONS IN RAIN/SNOW SHOWERS WEST OF THE LARAMIE RANGE WILL
SPREAD EAST ONTO THE PLAINS TONIGHT...WITH OCCASIONAL IFR POSSIBLE.
PRECIPITATION WILL TAPER OFF WITH IMPROVING CIGS/VSBYS SUNDAY
MORNING.

&&

.FIRE WEATHER...
ISSUED AT 209 PM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG THROUGH EARLY NEXT WEEK...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED DUE TO COOL TEMPERATURES AND HIGH
RELATIVE HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ112-114.

NE...WIND ADVISORY FROM 9 AM TO 6 PM MST SUNDAY FOR NEZ002-003-
     019>021-054-055-095-096.

&&

$$

UPDATE...MJ
SHORT TERM...TJT
LONG TERM...GCC
AVIATION...MJ
FIRE WEATHER...TJT




000
FXUS65 KCYS 230435
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
935 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 932 PM MST SAT NOV 22 2014

WINDS PER SURFACE/HIGHWAY OBSERVATIONS THE PAST FEW HOURS HAVE
SHOWN A GRADUAL DECREASING TREND...AND THE THREAT FOR HIGH WINDS
TONIGHT HAVE ENDED. THUS HAVE CANCELLED HIGH WIND WARNINGS. COLD
FRONT HAS MOVED THROUGH RIVERTON AND CASPER AND WILL CONTINUE
ITS STEADY SOUTHEASTWARD PROGRESS THROUGH THE CWA TONIGHT. GUSTY
NORTHWEST WINDS OF 35 TO 45 MPH WILL OCCUR BEHIND THE FRONT.

&&

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM MST SAT NOV 22 2014

PRIMARY CONCERNS THROUGH THIS WEEKEND WILL BE WINDS AND MOUNTAIN
SNOWFALL. MOST OF THE AREA WITHIN THE HIGH WIND WARNING HAS
VERIFIED THIS AFTERNOON WITH GUSTS AS HIGH AS 76 MPH REPORTED
ALONG I25 AND I80. ELSEWHERE...WINDS HAVE STRUGGLED ACROSS
LOCATIONS SUCH AS THE LARAMIE VALLEY AND THE HIGH PLAINS
IMMEDIATELY EAST OF THE LARAMIE RANGE. BELIEVE THIS IS DUE TO A
COMBINATION OF CLOUDY SKIES AND AN AREA OF POSITIVE OMEGA EAST OF
THE MOUNTAINS. WILL KEEP THE HIGH WIND WARNING OUT FOR THESE
AREAS...BUT THERE IS ONLY A SMALL WINDOW TO SEE GUSTS AROUND 55
MPH SINCE DOWNSLOPE AND SUBSIDENCE WILL BEGIN TO DIMINISH BY LATE
THIS EVENING. ENDED THE HIGH WIND WARNING AT MIDNIGHT TONIGHT
SINCE THE FRONT AND IS TRENDING A BIT FASTER AND SHOULD BE NEAR
THE COLORADO BORDER A FEW HOURS BEFORE MIDNIGHT. AFTER THE FRONT
AND ASSOCIATED TROUGH AXIS ALOFT MOVES THROUGH...WINDS WILL SHIFT
INTO THE NORTHWEST WHICH WILL END THE HIGH WIND EVENT BRIEFLY FOR
THE WIND PRONE AREAS AS WELL. HOWEVER...HIGH WINDS WILL LIKELY
RETURN BY LATE MONDAY NIGHT ACROSS MOST OF SOUTHEAST WYOMING.

SNOW WILL BE ANOTHER CONCERN...PRIMARILY ACROSS THE MOUNTAINS OF
SOUTHEAST WYOMING AND PERHAPS EVEN SOME OF THE HIGH VALLEYS. SNOW
IS DEVELOPING ACROSS THE MOUNTAINS EARLY THIS AFTERNOON WITH SOME
RAIN/SNOW MIX DOWN TO THE VALLEY FLOORS. ANY RAINFALL WILL QUICKLY
CHANGE TO SNOW LATE THIS AFTERNOON AS MUCH COLDER AIR MOVES INTO
THE AREA. THE HEAVIEST SNOW WILL BE TONIGHT...BUT ANOTHER
DISTURBANCE ALOFT WILL PUSH ACROSS THE AREA ON SUNDAY AS WELL
RESULTING IN SOME ENHANCEMENT OF SNOWFALL RATES. HIGH CONFIDENCE
THAT THE MOUNTAINS WILL DO WELL WITH THIS EVENT...SO KEPT THE
WINTER STORM WARNING GOING THROUGH MONDAY FOR 1 TO 2 FEET OF SNOW.
EXPECT THE PRECIPITATION TO BE ENHANCED FURTHER ON THE WEST TO
NORTHWEST FACING SLOPES AND RIDGES DUE TO UPSLOPE FLOW. FOR THE
VALLEYS AND HIGH PLAINS...EXPECT PERHAPS 1 TO 2 INCHES ALONG I80
WEST OF THE LARAMIE RANGE AND FURTHER NORTH ALONG I80 AROUND
DOUGLAS. THE CHEYENNE RIDGE FROM CHEYENNE TO SIDNEY INCLUDING MOST
OF THE NEBRASKA PANHANDLE WILL BE LUCKY TO SEE A DUSTING OF SNOW
DUE TO THE LARGE LOW LEVEL DOWNSLOPE COMPONENT TO THE WINDS. THE
BEST CHANCE TO SEE SOME SNOW WILL BE NEAR THE FRONTAL PASSAGE DUE
TO BRIEF FRONTOGENESIS AND LOW LEVEL DYNAMIC LIFT. THERE IS SOME
CONCERN THAT THE ADJACENT VALLEYS ACROSS SOUTHERN CARBON COUNTY
WILL SEE SOME MODERATE SNOWFALL RATES AS THE WINDS SHIFT INTO THE
NORTHWEST. WILL CONTINUE TO KEEP AN EYE ON THIS THROUGH SUNDAY AS
THE NEXT DISTURBANCE MOVES ACROSS THE AREA. FOR NOW...KEPT 1 TO 3
INCHES OF SNOW IN THESE LOCATIONS WITH 5 INCHES POSSIBLE LOCALLY.

FOR MONDAY...ANOTHER DISTURBANCE ALOFT WILL MOVE ACROSS THE
AREA...RESULTING IN ENHANCED SNOWFALL RATES ACROSS THE MOUNTAINS
AFTER A BRIEF LULL SUNDAY NIGHT. THIS MAY BE THE BEST CHANCE FOR
THE HIGH PLAINS TO RECEIVE SOME WIDESPREAD LIGHT SNOW
ACCUMULATIONS AS WINDS SHIFT INTO THE NORTH.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 300 PM MST SAT NOV 22 2014

STRONG WINDS CONTINUE THROUGH AT LEAST WEDNESDAY. GFS SHOWING A
1041MB SURFACE HIGH OVER WESTERN COLORADO TUESDAY MORNING WITH
A ROUGHLY 10-12MB SURFACE GRADIENT BETWEEN CASPER AND CRAIG.
700MB WINDS FROM THE NORTHWEST AT 50-60KTS WITH A 700MB HEIGHT
GRADIENT AROUND 70 TO 80 MARS BETWEEN CRAIG AND CASPER. ALMOST A
SURE THING FOR WIND WARNING CRITERIA AT LEAST FOR THE WIND PRONE
AREAS AND HAVE BUMPED UP GUIDANCE AT THESE LOCATIONS TO REFLECT
CONFIDENCE IN HIGH WINDS.

WINDS LOOK TO FINALLY EASE SOME THURSDAY AS WE SEE A FRONT DIVE
SOUTHWEST OUT OF THE DAKOTAS AND LAY UP AGAINST THE LARAMIE RANGE.
ECMWF A LITTLE FURTHER NORTHEAST WITH THIS FRONT OVER THE MORE
AGGRESSIVE GFS...FINALLY PUSHING THE BOUNDARY INTO THE LARAMIE
RANGE THURSDAY EVENING. DID GO AHEAD AND LOWER TEMPERATURES SOME
OVER THE NORTHERN PANHANDLE AND OUR EASTERN ZONES TO REFLECT THE
MUCH COLDER AIR BEHIND THE FRONT FOR THURSDAY THROUGH FRIDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 453 PM MST SAT NOV 22 2014

STRONG AND GUSTY WESTERLY WINDS WILL CONTINUE TONIGHT WITH THE
PASSAGE OF A PACIFIC COLD FRONT. GUSTS TO 50 KT WILL STILL BE
POSSIBLE EARLY THIS EVENING...MAINLY INVOF THE MOUNTAINS. GUSTS
WILL DECREASE TO 30-40 KT LATER THIS EVENING AND OVERNIGHT. MVFR
CONDITIONS IN RAIN/SNOW SHOWERS WEST OF THE LARAMIE RANGE WILL
SPREAD EAST ONTO THE PLAINS TONIGHT...WITH OCCASIONAL IFR POSSIBLE.
PRECIPITATION WILL TAPER OFF WITH IMPROVING CIGS/VSBYS SUNDAY
MORNING.

&&

.FIRE WEATHER...
ISSUED AT 209 PM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG THROUGH EARLY NEXT WEEK...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED DUE TO COOL TEMPERATURES AND HIGH
RELATIVE HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ112-114.

NE...WIND ADVISORY FROM 9 AM TO 6 PM MST SUNDAY FOR NEZ002-003-
     019>021-054-055-095-096.

&&

$$

UPDATE...MJ
SHORT TERM...TJT
LONG TERM...GCC
AVIATION...MJ
FIRE WEATHER...TJT



000
FXUS63 KUNR 230407
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
907 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 903 PM MST SAT NOV 22 2014

04Z SURFACE ANALYSIS HAD LOW NEAR CYQR WITH COLD FRONT TO KRAP TO
SOUTH CENTRAL WY. COUPLE OF HOURS OF GUSTY WINDS ASSOCIATED WITH
COLD FRONT AS WELL AS SOME -SHRASN. 00Z KUNR SOUNDING SHOWS LIFT
AHEAD OF SHORTWAVE OVER SOUTHEAST MT BEING WASTED ON SATURATION
EARLIER THIS EVENING. LATEST RADAR/OBSERVATIONS DO SUGGEST LOWER
TROPOSPHERE MOISTENING ENOUGH FOR PRECIPITATION TO REACH THE
GROUND...ESPECIALLY OVER NORTHWEST SD SO HAVE RAISED POPS THERE.

00Z GUIDANCE STILL SHOWS VERY WINDY DAY FOR MUCH OF THE AREA
SUNDAY. BUFKIT MOMENTUM TRANSFER INDICATES HIGH WIND WARNING
CRITERIA WINDS FROM K2WX TO KRAP DURING PEAK MIXING LATER SUNDAY
MORNING THROUGH LATE SUNDAY AFTERNOON...IN CONTRAST TO LESSER MOS
GUIDANCE WINDS. 40-50KT 850MB WINDS NOTED WITH SLIGHTLY HIGHER
VALUES HIGHER UP. STRONG SUBSIDENCE NOTED BEHIND TONIGHT/S
SHORTWAVE ALONG WITH WEAK COLD AIR ADVECTION DURING PEAK HEATING.
WILL CONVERT WATCH TO WARNING AND EXPAND ALONG THE FOOTHILLS A BIT
WITH UPDATE.

&&

.SHORT TERM...THIS EVENING THROUGH SUNDAY NIGHT
ISSUED AT 426 PM MST SAT NOV 22 2014

DEEPENING NW CONUS UPPER TROUGH WILL ADVECT THROUGH THE REGION
THROUGH SUNDAY...SUPPORTING A COLD FRONT INTO THE AREA...WITH
CHANCES FOR SNOW AND INCREASING WINDS. THERMAL RIDGE HAS SUPPORTED
A MILD DAY ACROSS THE AREA...ESP WHERE ENHANCED LOCAL MIXING HAS
OCCURRED. HOWEVER...INCREASING LSA WITH A LL COLD FRONT WILL
SUPPORT A WEAK FGEN BAND OF PRECIP ACROSS THE AREA TONIGHT.
SECONDARY COLD FRONT WITH STEEP LL LAPSE RATES AND CYCLONIC FLOW
ALOFT WILL THEN SUPPORT INCREASING CHANCES FOR DIURNALLY DRIVEN
SNOW SHOWERS SUNDAY...WITH FAVORABLE UPSLOPE FORCING OVER THE
NORTHERN HILLS. ACTIVE NW FLOW WILL SUSTAIN THROUGH SUNDAY
NIGHT...WITH ANOTHER IMPULSE EXPECTED TO INFLUENCE THE WESTERN FA
LATE SUNDAY.

TONIGHT...SPLITTING NW CONUS UPPER TROUGH WILL SUPPORT A WEAK HIGH
CENTERED FGEN RESPONSE OVER THE REGION WITH INCREASING MID LEVEL
MOISTURE. STEEP MID LEVEL LAPSE RATES COMBINED WITH SUFFICIENT MID
LEVEL MOISTURE AND INCREASING UVM SHOULD BE ENOUGH TO SUPPORT SCT
RAIN/SNOW SHOWERS OVER THE REGION...ESP NE WY WHERE BETTER FORCING
FOR ACCENT WILL BE IN PLACE. ANY PRECIP WILL MAINLY BE IN THE FORM OF
RAIN THIS EVENING...QUICKLY TRANSITIONING TO SNOW OVERNIGHT GIVEN
COOLING THERMAL FIELDS. ANY SNOW AMOUNTS WILL GENERALLY BE LESS THAN
ONE INCH. LL FLOW WILL VEER NW TONIGHT AND INCREASE AFTER MIDNIGHT.
INITIAL CAA PUSH AND PRESSURE RISES MAY SUPPORT A PERIOD OF NEAR ADV
WINDS AROUND KRAP AFTER MIDNIGHT. HOWEVER...WINDS SHOULD GENERALLY
REMAIN TAME UNTIL LATER SUNDAY MORNING.

SUNDAY...SECONDARY CAA PUSH AND INCREASING LL FLOW WILL SUPPORT A
WINDY DAY ACROSS THE REGION. MEAN BL FLOW PROGS SUPPORT SUSTAINED
WINDS OF 30-35 KNOTS ESP ACROSS FAR NW SD. BUFR PROGS INDICATE THE
POTENTIAL FOR WINDS OF 50 KNOTS TO MIX DOWN...ESP WITH THE SECONDARY
PRESSURE RISE SURGE EARLY SUNDAY AFTERNOON ACROSS THE FAR NW. IN
ADDITION...COLD POCKET ALOFT COMBINED WITH DIURNAL HEATING WILL
SUPPORT THE DEVELOPMENT OF SNOW SHOWERS...WITH LOCAL ENHANCED
DOWNWARD MOMENTUM TRANSPORT POSSIBLE IN THE VICINITY OF ANY SHOWER.
HAVE DECIDED TO ISSUE A WIND ADV FOR MUCH OF THE SD
PLAINS...RETAINING A HIGH WIND WATCH ACROSS THE FAR NW WHERE THE
BEST POTENTIAL FOR DOWNWARD MOMENTUM TRANSPORT OF 50 KNOT FLOW WILL
RESIDE. MEAN MODEL TRENDS HAVE SUPPORTED SLIGHTLY WEAKER WINDS
ACROSS THE AREA...BUT WOULD LIKE TO HAVE ANOTHER FORECAST RUN OR TWO
TO SEE IF THIS TREND SUSTAINS. THERE IS ALSO THE POTENTIAL FOR
LOCALIZED STRONG WINDS ALONG THE PLAINS OF THE EASTERN BLACK
HILLS...INCLUDING RAPID CITY...WITH NEAR HIGH WIND WARNING POSSIBLE.
HOWEVER...GIVEN THE LOW POTENTIAL/SHORT DURATION/AND LOCALIZED
NATURE...FEEL A WIND ADV IS MORE PRUDENT. THE OTHER HIGHLIGHT WILL
BE INCREASINGLY FAVORABLE CONDITIONS FOR UPSLOPE SNOWS ACROSS THE
NORTHERN BLACK HILLS...MAINLY FROM THE BEAR LODGE MOUNTAINS TO
CHEYENNE CROSSING. INCREASING FROUDE/MOISTURE/AND FLOW WITH COOLING
THERMAL FIELDS IN STEEP LL LAPSE RATES WILL SUPPORT A DECENT PERIOD
OF UPSLOPE FORCING...EXTENDING INTO THE DGZ. 1 TO 3 INCHES WITH
LOCALLY HIGHER AMOUNTS WILL BE POSSIBLE IN THIS AREA. SNOW WILL WIND
DOWN SUNDAY EVENING AS THE BL DRIES. HOWEVER...AS SECONDARY IMPULSE
WILL LEAD TO RENEWED CHANCES FOR SNOW...MAINLY NE WY LATE SUNDAY
NIGHT.

&&

.LONG TERM...MONDAY THROUGH SATURDAY
ISSUED AT 426 PM MST SAT NOV 22 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW ALOFT WILL
CONTINUE ACROSS THE NORTHERN HIGH PLAINS EARLY NEXT WEEK. SEVERAL
WEAK DISTURBANCES WITHIN NORTHWEST FLOW WILL SLIDE THROUGH...BRINGING
A GOOD DEAL OF CLOUDINESS AND CHANCES FOR SNOW SHOWERS AT TIMES
THROUGH WEDNESDAY. THE BEST CHANCES FOR SNOW WILL GENERALLY BE
ACROSS NORTHEAST WY AND THE NORTHERN BLACK HILLS AREA.

FOR THE HOLIDAY PERIOD...THE LATEST RUNS OF THE GFS...ECMWF...AND
CANADIAN HAVE ALL FLIPPED BACK TO A COLDER REGIME FOR LATE IN THE
WEEK AS A CANADIAN COLD FRONT IS PROGGED TO SLIDE SOUTH THROUGH THE
AREA LATE WEDNESDAY/WEDNESDAY NIGHT. WILL TREND COLDER AGAIN FOR
THANKSGIVING DAY AND THE REST OF THE EXTENDED...BUT UNCERTAINTY
STILL EXISTS WITH REGARD TO TEMPS. IT DOES CONTINUE TO LOOK MAINLY
DRY DURING THE PERIOD THOUGH.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING
ISSUED AT 426 PM MST SAT NOV 22 2014

A COLD FRONT WILL CROSS THE AREA TONIGHT...WITH GUSTY NORTHWEST
WINDS DEVELOPING BEHIND THE FRONT. A FEW RAIN SHOWERS ARE
EXPECTED THIS EVENING OVER MAINLY NORTHEAST WY AND FAR WESTERN
SD...CHANGING TO SNOW SHOWERS OVERNIGHT. SOME AREAS OF MVFR
CONDITIONS ARE EXPECTED...ESPECIALLY ACROSS FAR NORTHEAST WY AND
THE BLACK HILLS. STRONGER NORTHWEST WINDS WILL DEVELOP ACROSS THE
AREA SUNDAY MORNING.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY FROM 8 AM MST /9 AM CST/ TO 8 PM MST /9 PM CST/
     SUNDAY FOR SDZ014-025-027-032-041-043-044-046-047-049.

     HIGH WIND WARNING FROM 8 AM TO 8 PM MST SUNDAY FOR SDZ001-002-
     012-013-026-031-072-073.

WY...NONE.
&&

$$

UPDATE...HELGESON
SHORT TERM...JC
LONG TERM...26
AVIATION...26




000
FXUS63 KUNR 230407
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
907 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 903 PM MST SAT NOV 22 2014

04Z SURFACE ANALYSIS HAD LOW NEAR CYQR WITH COLD FRONT TO KRAP TO
SOUTH CENTRAL WY. COUPLE OF HOURS OF GUSTY WINDS ASSOCIATED WITH
COLD FRONT AS WELL AS SOME -SHRASN. 00Z KUNR SOUNDING SHOWS LIFT
AHEAD OF SHORTWAVE OVER SOUTHEAST MT BEING WASTED ON SATURATION
EARLIER THIS EVENING. LATEST RADAR/OBSERVATIONS DO SUGGEST LOWER
TROPOSPHERE MOISTENING ENOUGH FOR PRECIPITATION TO REACH THE
GROUND...ESPECIALLY OVER NORTHWEST SD SO HAVE RAISED POPS THERE.

00Z GUIDANCE STILL SHOWS VERY WINDY DAY FOR MUCH OF THE AREA
SUNDAY. BUFKIT MOMENTUM TRANSFER INDICATES HIGH WIND WARNING
CRITERIA WINDS FROM K2WX TO KRAP DURING PEAK MIXING LATER SUNDAY
MORNING THROUGH LATE SUNDAY AFTERNOON...IN CONTRAST TO LESSER MOS
GUIDANCE WINDS. 40-50KT 850MB WINDS NOTED WITH SLIGHTLY HIGHER
VALUES HIGHER UP. STRONG SUBSIDENCE NOTED BEHIND TONIGHT/S
SHORTWAVE ALONG WITH WEAK COLD AIR ADVECTION DURING PEAK HEATING.
WILL CONVERT WATCH TO WARNING AND EXPAND ALONG THE FOOTHILLS A BIT
WITH UPDATE.

&&

.SHORT TERM...THIS EVENING THROUGH SUNDAY NIGHT
ISSUED AT 426 PM MST SAT NOV 22 2014

DEEPENING NW CONUS UPPER TROUGH WILL ADVECT THROUGH THE REGION
THROUGH SUNDAY...SUPPORTING A COLD FRONT INTO THE AREA...WITH
CHANCES FOR SNOW AND INCREASING WINDS. THERMAL RIDGE HAS SUPPORTED
A MILD DAY ACROSS THE AREA...ESP WHERE ENHANCED LOCAL MIXING HAS
OCCURRED. HOWEVER...INCREASING LSA WITH A LL COLD FRONT WILL
SUPPORT A WEAK FGEN BAND OF PRECIP ACROSS THE AREA TONIGHT.
SECONDARY COLD FRONT WITH STEEP LL LAPSE RATES AND CYCLONIC FLOW
ALOFT WILL THEN SUPPORT INCREASING CHANCES FOR DIURNALLY DRIVEN
SNOW SHOWERS SUNDAY...WITH FAVORABLE UPSLOPE FORCING OVER THE
NORTHERN HILLS. ACTIVE NW FLOW WILL SUSTAIN THROUGH SUNDAY
NIGHT...WITH ANOTHER IMPULSE EXPECTED TO INFLUENCE THE WESTERN FA
LATE SUNDAY.

TONIGHT...SPLITTING NW CONUS UPPER TROUGH WILL SUPPORT A WEAK HIGH
CENTERED FGEN RESPONSE OVER THE REGION WITH INCREASING MID LEVEL
MOISTURE. STEEP MID LEVEL LAPSE RATES COMBINED WITH SUFFICIENT MID
LEVEL MOISTURE AND INCREASING UVM SHOULD BE ENOUGH TO SUPPORT SCT
RAIN/SNOW SHOWERS OVER THE REGION...ESP NE WY WHERE BETTER FORCING
FOR ACCENT WILL BE IN PLACE. ANY PRECIP WILL MAINLY BE IN THE FORM OF
RAIN THIS EVENING...QUICKLY TRANSITIONING TO SNOW OVERNIGHT GIVEN
COOLING THERMAL FIELDS. ANY SNOW AMOUNTS WILL GENERALLY BE LESS THAN
ONE INCH. LL FLOW WILL VEER NW TONIGHT AND INCREASE AFTER MIDNIGHT.
INITIAL CAA PUSH AND PRESSURE RISES MAY SUPPORT A PERIOD OF NEAR ADV
WINDS AROUND KRAP AFTER MIDNIGHT. HOWEVER...WINDS SHOULD GENERALLY
REMAIN TAME UNTIL LATER SUNDAY MORNING.

SUNDAY...SECONDARY CAA PUSH AND INCREASING LL FLOW WILL SUPPORT A
WINDY DAY ACROSS THE REGION. MEAN BL FLOW PROGS SUPPORT SUSTAINED
WINDS OF 30-35 KNOTS ESP ACROSS FAR NW SD. BUFR PROGS INDICATE THE
POTENTIAL FOR WINDS OF 50 KNOTS TO MIX DOWN...ESP WITH THE SECONDARY
PRESSURE RISE SURGE EARLY SUNDAY AFTERNOON ACROSS THE FAR NW. IN
ADDITION...COLD POCKET ALOFT COMBINED WITH DIURNAL HEATING WILL
SUPPORT THE DEVELOPMENT OF SNOW SHOWERS...WITH LOCAL ENHANCED
DOWNWARD MOMENTUM TRANSPORT POSSIBLE IN THE VICINITY OF ANY SHOWER.
HAVE DECIDED TO ISSUE A WIND ADV FOR MUCH OF THE SD
PLAINS...RETAINING A HIGH WIND WATCH ACROSS THE FAR NW WHERE THE
BEST POTENTIAL FOR DOWNWARD MOMENTUM TRANSPORT OF 50 KNOT FLOW WILL
RESIDE. MEAN MODEL TRENDS HAVE SUPPORTED SLIGHTLY WEAKER WINDS
ACROSS THE AREA...BUT WOULD LIKE TO HAVE ANOTHER FORECAST RUN OR TWO
TO SEE IF THIS TREND SUSTAINS. THERE IS ALSO THE POTENTIAL FOR
LOCALIZED STRONG WINDS ALONG THE PLAINS OF THE EASTERN BLACK
HILLS...INCLUDING RAPID CITY...WITH NEAR HIGH WIND WARNING POSSIBLE.
HOWEVER...GIVEN THE LOW POTENTIAL/SHORT DURATION/AND LOCALIZED
NATURE...FEEL A WIND ADV IS MORE PRUDENT. THE OTHER HIGHLIGHT WILL
BE INCREASINGLY FAVORABLE CONDITIONS FOR UPSLOPE SNOWS ACROSS THE
NORTHERN BLACK HILLS...MAINLY FROM THE BEAR LODGE MOUNTAINS TO
CHEYENNE CROSSING. INCREASING FROUDE/MOISTURE/AND FLOW WITH COOLING
THERMAL FIELDS IN STEEP LL LAPSE RATES WILL SUPPORT A DECENT PERIOD
OF UPSLOPE FORCING...EXTENDING INTO THE DGZ. 1 TO 3 INCHES WITH
LOCALLY HIGHER AMOUNTS WILL BE POSSIBLE IN THIS AREA. SNOW WILL WIND
DOWN SUNDAY EVENING AS THE BL DRIES. HOWEVER...AS SECONDARY IMPULSE
WILL LEAD TO RENEWED CHANCES FOR SNOW...MAINLY NE WY LATE SUNDAY
NIGHT.

&&

.LONG TERM...MONDAY THROUGH SATURDAY
ISSUED AT 426 PM MST SAT NOV 22 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW ALOFT WILL
CONTINUE ACROSS THE NORTHERN HIGH PLAINS EARLY NEXT WEEK. SEVERAL
WEAK DISTURBANCES WITHIN NORTHWEST FLOW WILL SLIDE THROUGH...BRINGING
A GOOD DEAL OF CLOUDINESS AND CHANCES FOR SNOW SHOWERS AT TIMES
THROUGH WEDNESDAY. THE BEST CHANCES FOR SNOW WILL GENERALLY BE
ACROSS NORTHEAST WY AND THE NORTHERN BLACK HILLS AREA.

FOR THE HOLIDAY PERIOD...THE LATEST RUNS OF THE GFS...ECMWF...AND
CANADIAN HAVE ALL FLIPPED BACK TO A COLDER REGIME FOR LATE IN THE
WEEK AS A CANADIAN COLD FRONT IS PROGGED TO SLIDE SOUTH THROUGH THE
AREA LATE WEDNESDAY/WEDNESDAY NIGHT. WILL TREND COLDER AGAIN FOR
THANKSGIVING DAY AND THE REST OF THE EXTENDED...BUT UNCERTAINTY
STILL EXISTS WITH REGARD TO TEMPS. IT DOES CONTINUE TO LOOK MAINLY
DRY DURING THE PERIOD THOUGH.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING
ISSUED AT 426 PM MST SAT NOV 22 2014

A COLD FRONT WILL CROSS THE AREA TONIGHT...WITH GUSTY NORTHWEST
WINDS DEVELOPING BEHIND THE FRONT. A FEW RAIN SHOWERS ARE
EXPECTED THIS EVENING OVER MAINLY NORTHEAST WY AND FAR WESTERN
SD...CHANGING TO SNOW SHOWERS OVERNIGHT. SOME AREAS OF MVFR
CONDITIONS ARE EXPECTED...ESPECIALLY ACROSS FAR NORTHEAST WY AND
THE BLACK HILLS. STRONGER NORTHWEST WINDS WILL DEVELOP ACROSS THE
AREA SUNDAY MORNING.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY FROM 8 AM MST /9 AM CST/ TO 8 PM MST /9 PM CST/
     SUNDAY FOR SDZ014-025-027-032-041-043-044-046-047-049.

     HIGH WIND WARNING FROM 8 AM TO 8 PM MST SUNDAY FOR SDZ001-002-
     012-013-026-031-072-073.

WY...NONE.
&&

$$

UPDATE...HELGESON
SHORT TERM...JC
LONG TERM...26
AVIATION...26





000
FXUS63 KUNR 230407
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
907 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 903 PM MST SAT NOV 22 2014

04Z SURFACE ANALYSIS HAD LOW NEAR CYQR WITH COLD FRONT TO KRAP TO
SOUTH CENTRAL WY. COUPLE OF HOURS OF GUSTY WINDS ASSOCIATED WITH
COLD FRONT AS WELL AS SOME -SHRASN. 00Z KUNR SOUNDING SHOWS LIFT
AHEAD OF SHORTWAVE OVER SOUTHEAST MT BEING WASTED ON SATURATION
EARLIER THIS EVENING. LATEST RADAR/OBSERVATIONS DO SUGGEST LOWER
TROPOSPHERE MOISTENING ENOUGH FOR PRECIPITATION TO REACH THE
GROUND...ESPECIALLY OVER NORTHWEST SD SO HAVE RAISED POPS THERE.

00Z GUIDANCE STILL SHOWS VERY WINDY DAY FOR MUCH OF THE AREA
SUNDAY. BUFKIT MOMENTUM TRANSFER INDICATES HIGH WIND WARNING
CRITERIA WINDS FROM K2WX TO KRAP DURING PEAK MIXING LATER SUNDAY
MORNING THROUGH LATE SUNDAY AFTERNOON...IN CONTRAST TO LESSER MOS
GUIDANCE WINDS. 40-50KT 850MB WINDS NOTED WITH SLIGHTLY HIGHER
VALUES HIGHER UP. STRONG SUBSIDENCE NOTED BEHIND TONIGHT/S
SHORTWAVE ALONG WITH WEAK COLD AIR ADVECTION DURING PEAK HEATING.
WILL CONVERT WATCH TO WARNING AND EXPAND ALONG THE FOOTHILLS A BIT
WITH UPDATE.

&&

.SHORT TERM...THIS EVENING THROUGH SUNDAY NIGHT
ISSUED AT 426 PM MST SAT NOV 22 2014

DEEPENING NW CONUS UPPER TROUGH WILL ADVECT THROUGH THE REGION
THROUGH SUNDAY...SUPPORTING A COLD FRONT INTO THE AREA...WITH
CHANCES FOR SNOW AND INCREASING WINDS. THERMAL RIDGE HAS SUPPORTED
A MILD DAY ACROSS THE AREA...ESP WHERE ENHANCED LOCAL MIXING HAS
OCCURRED. HOWEVER...INCREASING LSA WITH A LL COLD FRONT WILL
SUPPORT A WEAK FGEN BAND OF PRECIP ACROSS THE AREA TONIGHT.
SECONDARY COLD FRONT WITH STEEP LL LAPSE RATES AND CYCLONIC FLOW
ALOFT WILL THEN SUPPORT INCREASING CHANCES FOR DIURNALLY DRIVEN
SNOW SHOWERS SUNDAY...WITH FAVORABLE UPSLOPE FORCING OVER THE
NORTHERN HILLS. ACTIVE NW FLOW WILL SUSTAIN THROUGH SUNDAY
NIGHT...WITH ANOTHER IMPULSE EXPECTED TO INFLUENCE THE WESTERN FA
LATE SUNDAY.

TONIGHT...SPLITTING NW CONUS UPPER TROUGH WILL SUPPORT A WEAK HIGH
CENTERED FGEN RESPONSE OVER THE REGION WITH INCREASING MID LEVEL
MOISTURE. STEEP MID LEVEL LAPSE RATES COMBINED WITH SUFFICIENT MID
LEVEL MOISTURE AND INCREASING UVM SHOULD BE ENOUGH TO SUPPORT SCT
RAIN/SNOW SHOWERS OVER THE REGION...ESP NE WY WHERE BETTER FORCING
FOR ACCENT WILL BE IN PLACE. ANY PRECIP WILL MAINLY BE IN THE FORM OF
RAIN THIS EVENING...QUICKLY TRANSITIONING TO SNOW OVERNIGHT GIVEN
COOLING THERMAL FIELDS. ANY SNOW AMOUNTS WILL GENERALLY BE LESS THAN
ONE INCH. LL FLOW WILL VEER NW TONIGHT AND INCREASE AFTER MIDNIGHT.
INITIAL CAA PUSH AND PRESSURE RISES MAY SUPPORT A PERIOD OF NEAR ADV
WINDS AROUND KRAP AFTER MIDNIGHT. HOWEVER...WINDS SHOULD GENERALLY
REMAIN TAME UNTIL LATER SUNDAY MORNING.

SUNDAY...SECONDARY CAA PUSH AND INCREASING LL FLOW WILL SUPPORT A
WINDY DAY ACROSS THE REGION. MEAN BL FLOW PROGS SUPPORT SUSTAINED
WINDS OF 30-35 KNOTS ESP ACROSS FAR NW SD. BUFR PROGS INDICATE THE
POTENTIAL FOR WINDS OF 50 KNOTS TO MIX DOWN...ESP WITH THE SECONDARY
PRESSURE RISE SURGE EARLY SUNDAY AFTERNOON ACROSS THE FAR NW. IN
ADDITION...COLD POCKET ALOFT COMBINED WITH DIURNAL HEATING WILL
SUPPORT THE DEVELOPMENT OF SNOW SHOWERS...WITH LOCAL ENHANCED
DOWNWARD MOMENTUM TRANSPORT POSSIBLE IN THE VICINITY OF ANY SHOWER.
HAVE DECIDED TO ISSUE A WIND ADV FOR MUCH OF THE SD
PLAINS...RETAINING A HIGH WIND WATCH ACROSS THE FAR NW WHERE THE
BEST POTENTIAL FOR DOWNWARD MOMENTUM TRANSPORT OF 50 KNOT FLOW WILL
RESIDE. MEAN MODEL TRENDS HAVE SUPPORTED SLIGHTLY WEAKER WINDS
ACROSS THE AREA...BUT WOULD LIKE TO HAVE ANOTHER FORECAST RUN OR TWO
TO SEE IF THIS TREND SUSTAINS. THERE IS ALSO THE POTENTIAL FOR
LOCALIZED STRONG WINDS ALONG THE PLAINS OF THE EASTERN BLACK
HILLS...INCLUDING RAPID CITY...WITH NEAR HIGH WIND WARNING POSSIBLE.
HOWEVER...GIVEN THE LOW POTENTIAL/SHORT DURATION/AND LOCALIZED
NATURE...FEEL A WIND ADV IS MORE PRUDENT. THE OTHER HIGHLIGHT WILL
BE INCREASINGLY FAVORABLE CONDITIONS FOR UPSLOPE SNOWS ACROSS THE
NORTHERN BLACK HILLS...MAINLY FROM THE BEAR LODGE MOUNTAINS TO
CHEYENNE CROSSING. INCREASING FROUDE/MOISTURE/AND FLOW WITH COOLING
THERMAL FIELDS IN STEEP LL LAPSE RATES WILL SUPPORT A DECENT PERIOD
OF UPSLOPE FORCING...EXTENDING INTO THE DGZ. 1 TO 3 INCHES WITH
LOCALLY HIGHER AMOUNTS WILL BE POSSIBLE IN THIS AREA. SNOW WILL WIND
DOWN SUNDAY EVENING AS THE BL DRIES. HOWEVER...AS SECONDARY IMPULSE
WILL LEAD TO RENEWED CHANCES FOR SNOW...MAINLY NE WY LATE SUNDAY
NIGHT.

&&

.LONG TERM...MONDAY THROUGH SATURDAY
ISSUED AT 426 PM MST SAT NOV 22 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW ALOFT WILL
CONTINUE ACROSS THE NORTHERN HIGH PLAINS EARLY NEXT WEEK. SEVERAL
WEAK DISTURBANCES WITHIN NORTHWEST FLOW WILL SLIDE THROUGH...BRINGING
A GOOD DEAL OF CLOUDINESS AND CHANCES FOR SNOW SHOWERS AT TIMES
THROUGH WEDNESDAY. THE BEST CHANCES FOR SNOW WILL GENERALLY BE
ACROSS NORTHEAST WY AND THE NORTHERN BLACK HILLS AREA.

FOR THE HOLIDAY PERIOD...THE LATEST RUNS OF THE GFS...ECMWF...AND
CANADIAN HAVE ALL FLIPPED BACK TO A COLDER REGIME FOR LATE IN THE
WEEK AS A CANADIAN COLD FRONT IS PROGGED TO SLIDE SOUTH THROUGH THE
AREA LATE WEDNESDAY/WEDNESDAY NIGHT. WILL TREND COLDER AGAIN FOR
THANKSGIVING DAY AND THE REST OF THE EXTENDED...BUT UNCERTAINTY
STILL EXISTS WITH REGARD TO TEMPS. IT DOES CONTINUE TO LOOK MAINLY
DRY DURING THE PERIOD THOUGH.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING
ISSUED AT 426 PM MST SAT NOV 22 2014

A COLD FRONT WILL CROSS THE AREA TONIGHT...WITH GUSTY NORTHWEST
WINDS DEVELOPING BEHIND THE FRONT. A FEW RAIN SHOWERS ARE
EXPECTED THIS EVENING OVER MAINLY NORTHEAST WY AND FAR WESTERN
SD...CHANGING TO SNOW SHOWERS OVERNIGHT. SOME AREAS OF MVFR
CONDITIONS ARE EXPECTED...ESPECIALLY ACROSS FAR NORTHEAST WY AND
THE BLACK HILLS. STRONGER NORTHWEST WINDS WILL DEVELOP ACROSS THE
AREA SUNDAY MORNING.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY FROM 8 AM MST /9 AM CST/ TO 8 PM MST /9 PM CST/
     SUNDAY FOR SDZ014-025-027-032-041-043-044-046-047-049.

     HIGH WIND WARNING FROM 8 AM TO 8 PM MST SUNDAY FOR SDZ001-002-
     012-013-026-031-072-073.

WY...NONE.
&&

$$

UPDATE...HELGESON
SHORT TERM...JC
LONG TERM...26
AVIATION...26




000
FXUS63 KUNR 230407
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
907 PM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 903 PM MST SAT NOV 22 2014

04Z SURFACE ANALYSIS HAD LOW NEAR CYQR WITH COLD FRONT TO KRAP TO
SOUTH CENTRAL WY. COUPLE OF HOURS OF GUSTY WINDS ASSOCIATED WITH
COLD FRONT AS WELL AS SOME -SHRASN. 00Z KUNR SOUNDING SHOWS LIFT
AHEAD OF SHORTWAVE OVER SOUTHEAST MT BEING WASTED ON SATURATION
EARLIER THIS EVENING. LATEST RADAR/OBSERVATIONS DO SUGGEST LOWER
TROPOSPHERE MOISTENING ENOUGH FOR PRECIPITATION TO REACH THE
GROUND...ESPECIALLY OVER NORTHWEST SD SO HAVE RAISED POPS THERE.

00Z GUIDANCE STILL SHOWS VERY WINDY DAY FOR MUCH OF THE AREA
SUNDAY. BUFKIT MOMENTUM TRANSFER INDICATES HIGH WIND WARNING
CRITERIA WINDS FROM K2WX TO KRAP DURING PEAK MIXING LATER SUNDAY
MORNING THROUGH LATE SUNDAY AFTERNOON...IN CONTRAST TO LESSER MOS
GUIDANCE WINDS. 40-50KT 850MB WINDS NOTED WITH SLIGHTLY HIGHER
VALUES HIGHER UP. STRONG SUBSIDENCE NOTED BEHIND TONIGHT/S
SHORTWAVE ALONG WITH WEAK COLD AIR ADVECTION DURING PEAK HEATING.
WILL CONVERT WATCH TO WARNING AND EXPAND ALONG THE FOOTHILLS A BIT
WITH UPDATE.

&&

.SHORT TERM...THIS EVENING THROUGH SUNDAY NIGHT
ISSUED AT 426 PM MST SAT NOV 22 2014

DEEPENING NW CONUS UPPER TROUGH WILL ADVECT THROUGH THE REGION
THROUGH SUNDAY...SUPPORTING A COLD FRONT INTO THE AREA...WITH
CHANCES FOR SNOW AND INCREASING WINDS. THERMAL RIDGE HAS SUPPORTED
A MILD DAY ACROSS THE AREA...ESP WHERE ENHANCED LOCAL MIXING HAS
OCCURRED. HOWEVER...INCREASING LSA WITH A LL COLD FRONT WILL
SUPPORT A WEAK FGEN BAND OF PRECIP ACROSS THE AREA TONIGHT.
SECONDARY COLD FRONT WITH STEEP LL LAPSE RATES AND CYCLONIC FLOW
ALOFT WILL THEN SUPPORT INCREASING CHANCES FOR DIURNALLY DRIVEN
SNOW SHOWERS SUNDAY...WITH FAVORABLE UPSLOPE FORCING OVER THE
NORTHERN HILLS. ACTIVE NW FLOW WILL SUSTAIN THROUGH SUNDAY
NIGHT...WITH ANOTHER IMPULSE EXPECTED TO INFLUENCE THE WESTERN FA
LATE SUNDAY.

TONIGHT...SPLITTING NW CONUS UPPER TROUGH WILL SUPPORT A WEAK HIGH
CENTERED FGEN RESPONSE OVER THE REGION WITH INCREASING MID LEVEL
MOISTURE. STEEP MID LEVEL LAPSE RATES COMBINED WITH SUFFICIENT MID
LEVEL MOISTURE AND INCREASING UVM SHOULD BE ENOUGH TO SUPPORT SCT
RAIN/SNOW SHOWERS OVER THE REGION...ESP NE WY WHERE BETTER FORCING
FOR ACCENT WILL BE IN PLACE. ANY PRECIP WILL MAINLY BE IN THE FORM OF
RAIN THIS EVENING...QUICKLY TRANSITIONING TO SNOW OVERNIGHT GIVEN
COOLING THERMAL FIELDS. ANY SNOW AMOUNTS WILL GENERALLY BE LESS THAN
ONE INCH. LL FLOW WILL VEER NW TONIGHT AND INCREASE AFTER MIDNIGHT.
INITIAL CAA PUSH AND PRESSURE RISES MAY SUPPORT A PERIOD OF NEAR ADV
WINDS AROUND KRAP AFTER MIDNIGHT. HOWEVER...WINDS SHOULD GENERALLY
REMAIN TAME UNTIL LATER SUNDAY MORNING.

SUNDAY...SECONDARY CAA PUSH AND INCREASING LL FLOW WILL SUPPORT A
WINDY DAY ACROSS THE REGION. MEAN BL FLOW PROGS SUPPORT SUSTAINED
WINDS OF 30-35 KNOTS ESP ACROSS FAR NW SD. BUFR PROGS INDICATE THE
POTENTIAL FOR WINDS OF 50 KNOTS TO MIX DOWN...ESP WITH THE SECONDARY
PRESSURE RISE SURGE EARLY SUNDAY AFTERNOON ACROSS THE FAR NW. IN
ADDITION...COLD POCKET ALOFT COMBINED WITH DIURNAL HEATING WILL
SUPPORT THE DEVELOPMENT OF SNOW SHOWERS...WITH LOCAL ENHANCED
DOWNWARD MOMENTUM TRANSPORT POSSIBLE IN THE VICINITY OF ANY SHOWER.
HAVE DECIDED TO ISSUE A WIND ADV FOR MUCH OF THE SD
PLAINS...RETAINING A HIGH WIND WATCH ACROSS THE FAR NW WHERE THE
BEST POTENTIAL FOR DOWNWARD MOMENTUM TRANSPORT OF 50 KNOT FLOW WILL
RESIDE. MEAN MODEL TRENDS HAVE SUPPORTED SLIGHTLY WEAKER WINDS
ACROSS THE AREA...BUT WOULD LIKE TO HAVE ANOTHER FORECAST RUN OR TWO
TO SEE IF THIS TREND SUSTAINS. THERE IS ALSO THE POTENTIAL FOR
LOCALIZED STRONG WINDS ALONG THE PLAINS OF THE EASTERN BLACK
HILLS...INCLUDING RAPID CITY...WITH NEAR HIGH WIND WARNING POSSIBLE.
HOWEVER...GIVEN THE LOW POTENTIAL/SHORT DURATION/AND LOCALIZED
NATURE...FEEL A WIND ADV IS MORE PRUDENT. THE OTHER HIGHLIGHT WILL
BE INCREASINGLY FAVORABLE CONDITIONS FOR UPSLOPE SNOWS ACROSS THE
NORTHERN BLACK HILLS...MAINLY FROM THE BEAR LODGE MOUNTAINS TO
CHEYENNE CROSSING. INCREASING FROUDE/MOISTURE/AND FLOW WITH COOLING
THERMAL FIELDS IN STEEP LL LAPSE RATES WILL SUPPORT A DECENT PERIOD
OF UPSLOPE FORCING...EXTENDING INTO THE DGZ. 1 TO 3 INCHES WITH
LOCALLY HIGHER AMOUNTS WILL BE POSSIBLE IN THIS AREA. SNOW WILL WIND
DOWN SUNDAY EVENING AS THE BL DRIES. HOWEVER...AS SECONDARY IMPULSE
WILL LEAD TO RENEWED CHANCES FOR SNOW...MAINLY NE WY LATE SUNDAY
NIGHT.

&&

.LONG TERM...MONDAY THROUGH SATURDAY
ISSUED AT 426 PM MST SAT NOV 22 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW ALOFT WILL
CONTINUE ACROSS THE NORTHERN HIGH PLAINS EARLY NEXT WEEK. SEVERAL
WEAK DISTURBANCES WITHIN NORTHWEST FLOW WILL SLIDE THROUGH...BRINGING
A GOOD DEAL OF CLOUDINESS AND CHANCES FOR SNOW SHOWERS AT TIMES
THROUGH WEDNESDAY. THE BEST CHANCES FOR SNOW WILL GENERALLY BE
ACROSS NORTHEAST WY AND THE NORTHERN BLACK HILLS AREA.

FOR THE HOLIDAY PERIOD...THE LATEST RUNS OF THE GFS...ECMWF...AND
CANADIAN HAVE ALL FLIPPED BACK TO A COLDER REGIME FOR LATE IN THE
WEEK AS A CANADIAN COLD FRONT IS PROGGED TO SLIDE SOUTH THROUGH THE
AREA LATE WEDNESDAY/WEDNESDAY NIGHT. WILL TREND COLDER AGAIN FOR
THANKSGIVING DAY AND THE REST OF THE EXTENDED...BUT UNCERTAINTY
STILL EXISTS WITH REGARD TO TEMPS. IT DOES CONTINUE TO LOOK MAINLY
DRY DURING THE PERIOD THOUGH.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING
ISSUED AT 426 PM MST SAT NOV 22 2014

A COLD FRONT WILL CROSS THE AREA TONIGHT...WITH GUSTY NORTHWEST
WINDS DEVELOPING BEHIND THE FRONT. A FEW RAIN SHOWERS ARE
EXPECTED THIS EVENING OVER MAINLY NORTHEAST WY AND FAR WESTERN
SD...CHANGING TO SNOW SHOWERS OVERNIGHT. SOME AREAS OF MVFR
CONDITIONS ARE EXPECTED...ESPECIALLY ACROSS FAR NORTHEAST WY AND
THE BLACK HILLS. STRONGER NORTHWEST WINDS WILL DEVELOP ACROSS THE
AREA SUNDAY MORNING.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY FROM 8 AM MST /9 AM CST/ TO 8 PM MST /9 PM CST/
     SUNDAY FOR SDZ014-025-027-032-041-043-044-046-047-049.

     HIGH WIND WARNING FROM 8 AM TO 8 PM MST SUNDAY FOR SDZ001-002-
     012-013-026-031-072-073.

WY...NONE.
&&

$$

UPDATE...HELGESON
SHORT TERM...JC
LONG TERM...26
AVIATION...26





000
FXUS65 KRIW 230338
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
838 PM MST SAT NOV 22 2014

.UPDATE...SNOW HAS TAPERED OFF OR ENDED BEHIND A COLD FRONT ACROSS
MOST OF WESTERN WYOMING. ANOTHER SHORTWAVE MOVING EAST ACROSS
IDAHO WILL BRING ANOTHER SHOT OF LIGHT TO MODERATE SNOW INTO FAR
WEST WYOMING AFTER MIDNIGHT. CANCELLED WINTER HIGHLIGHTS FOR ALL
AREAS BUT JACKSON HOLE VALLEY...STAR VALLEY AND SURROUNDING
MOUNTAINS WHERE WINTER STORM WARNINGS REMAIN IN EFFECT UNTIL 6 AM
SUNDAY. COLD FRONT HAS ALSO ENDED THE HIGH WIND THREAT ACROSS
CENTRAL WYOMING...SO HIGH WIND WARNINGS WERE CANCELLED. UPGRADED
HIGH WIND WATCH TO A WARNING FOR ONLY NORTHEAST JOHNSON COUNTY ON
SUNDAY. LATEST MODEL RUNS NOT AS BULLISH WITH STRONG WINDS FURTHER
WEST ACROSS THE WIND RIVER BASIN.

&&

.PREV DISCUSSION... /ISSUED 210 PM MST SAT NOV 22 2014/

SHORT TERM...TONIGHT THROUGH SUNDAY

A PACIFIC COLD FRONT APPROACHING WESTERN WYOMING WILL MOVE THROUGH
WESTERN AND CENTRAL WYOMING THROUGH THE NIGHT.  THE SNOW INTENSITIES
WILL DECREASE WITH THE PASSING OF THE COLD FRONT IN THE WESTERN
M0MOUNTAINS.  MOST AREAS EXPERIENCING HIGH WINDS TODAY WILL SEE
WINDS DECREASE AS THEY SHIFT TO THE NORTHWEST. HIGH WIND WATCHES
REMAIN FOR NORTHERN JOHNSON AND THE WIND RIVER BASIN WITH THE
NORTHWEST WINDS AS THESE AREAS FAVOR HIGH WINDS WITH NORTHWEST
WINDS AND COLD AIR ADVECTION. AREAS EAST OF THE CONTINENTAL DIVIDE
CAN EXPECT A QUICK BURST OF SNOWFALL BEHIND THE COLD FRONT WITH
LIGHT ACCUMULATIONS. OVERALL SNOWFALL WILL BE TAPERING OFF
THROUGH THE MORNING WITH SOME LINGERING MOUNTAIN SNOW SHOWERS ON
SUNDAY. TEMPERATURES WILL COOL ABOUT TEN DEGREES FROM TODAY.

LONG TERM...SUNDAY NIGHT THROUGH SATURDAY

BEHIND THE MAIN SHORTWAVE THAT WILL BE SWINGING THROUGH THIS
WEEKEND...A SECONDARY PIECE OF ENERGY WILL BE SLIDING DOWN THE BACK
SIDE OF THE MAIN TROUGH AXIS ACROSS THE CWA FAIRLY QUICKLY AROUND
12Z MONDAY. WITH WEAK ISENTROPIC LIFT IN THE WEST AHEAD OF THIS
SYSTEM AS WELL AS SOME WEAK QG FORCING IN THE SOUTHWEST...KEPT IDEA
OF ANOTHER 3 TO 6 INCHES OF SNOWFALL IN THE WESTERN MTNS SUNDAY INTO
MONDAY ALONG WITH ANOTHER 2 TO 3 INCHES IN THE WESTERN VALLEYS. THE
SNOW INTENSITY WILL BEGIN TO DECREASE MONDAY AFTERNOON. DURING THE
TROUGH PASSAGE...AROUND 12Z MONDAY...THERE WILL BE A BRIEF PERIOD WHEN THE
SNOWFALL SPILLS OVER TO AREAS EAST OF THE DIVIDE WITH THE MOST
SIGNIFICANT SNOWFALL OCCURRING IN THE BIG HORN MTNS WHERE 3 TO 5
INCHES ARE EXPECTED. THE SNOWFALL WILL DECREASE EAST OF THE DIVIDE
IN THE AFTERNOON AS WELL.

THE NEXT ANTICIPATED SNOW EVENT WILL OCCUR WHEN THE JET STREAM
SHIFTS NORTHEAST PLACING THE FASTER NORTHWEST FLOW ALOFT OVER
WYOMING BY 12Z TUESDAY. THIS WILL DRAW IN ADDITIONAL PACIFIC
MOISTURE FROM THE NORTHWEST ALONG WITH ISENTROPIC LIFT OVER WESTERN
WY TUESDAY WITH AN EXTENSIVE AREA OF ISENTROPIC LIFT SHIFTING TO OUR
NORTH OVER MONTANA BY TUESDAY NIGHT. THIS WILL JUSTIFY LIKELY POPS
IN THE WESTERN/BIG HORN MTNS AS WELL AS CHC POPS OVER THE NORTH HALF
OF THE LOWER ELEVATIONS OF THE CWA TUE/TUE NIGHT. THE JET STREAM
WILL THEN SHIFT NORTHEAST OF THE CWA BY WEDNESDAY.

AFTER THIS TIME FRAME...THE MODELS DIVERGE ONCE AGAIN WITH THE EURO
NOW THE MORE OPTIMISTIC MODEL PLACING A RIDGE OVER WY BY THURSDAY
AND THE GFS KEEPING THE DIRTY NORTHWEST FLOW OVER US THROUGH FRIDAY
WHICH IS IRONIC BECAUSE A COUPLE OF DAYS AGO BOTH THESE MODELS
PORTRAYED OPPOSITE SOLNS WITH THE GFS ADVERTISING A BUILDING RIDGE
AND THE EURO A POTENTIAL SNOW EVENT FOR THANKSGIVING. WITH THE
MODELS FLIP FLOPPING AND NO RUN TO RUN CONSISTENCY...ALL WE ARE
GOING TO DO IS INCREASE THE POPS A TAD OVER MAINLY NW WY FOR THE
SECOND HALF OF NEXT WEEK JUST IN CASE A SNOW EVENT DOES TAKE PLACE
DURING THIS TIME FRAME. MORE SPECIFICALLY...THE GFS PULLS IN COLDER
AIR FROM THE NORTHEAST OVER WY WITH MOST OF THE ASCT ISENTROPIC LIFT
FROM THIS ASCT WEATHER DISTURBANCE REMAINING TO OUR NORTH UP IN MT.

BY FRIDAY NIGHT...THE NW FLOW WILL BACK TO THE WEST AS THE RIDGE
FLATTENS. A MINOR DISTURBANCE MOVING THROUGH THE FLATTENING RIDGE
WITH ITS SHARE OF ISENTROPIC LIFT COULD BRING SOME LIGHT SNOW TO THE
FAR WEST SATURDAY.

TEMPERATURES NEXT WEEK WILL DEPEND LARGELY UPON WHETHER THE GFS OR
THE EURO PANS OUT SO KIND OF WENT WITH A BLEND. IN ANY EVENT...TEMPS
WILL BE MUCH MILDER THAN THEY HAVE BEEN DURING THE LAST COUPLE OF
WEEKS GIVEN THE LACK OF ANY ARCTIC INTRUSIONS NEXT WEEK.

AVIATION.../00Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES

AREAS OF LLWS WILL CONTINUE OVER THE CENTRAL BASINS AS WEST WINDS
FL070-100 BETWEEN 45-50KTS THROUGH 06Z. THESE STRONGER WINDS WILL
MIX DOWN TO THE SURFACE FROM VCNTY 50NE SM KRKS-KCPR AND FROM
VCNTY KCOD- KDUB WHERE HIGH WIND WARNINGS ARE IN EFFECT. A STRONG
COLD FRONT WILL PUSH ACROSS THE AREA EARLY THIS EVENING. MTNS WILL
BE MOSTLY OBSCURED ALONG THE DIVIDE AHEAD OF THE FRONT WITH SOME
BLOW OVER PCPN IN THE VCNTY OF KLND-KCOD. A BAND OF SNOW WILL
LIKELY ACCOMPANY THE FRONT THIS EVENING ALONG WITH AREAS OF
MVFR/IFR -SN MAINLY VCNTY ALONG AND EAST OF THE BIGHORN RANGE AND
INTERSTATE 25. AREAS OF SFC NW WINDS AT 20-30KTS WITH GUSTS TO
40KTS WILL FOLLOW THE FRONT...DECREASING AFTER 06Z.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES

MVFR/IFR CEILINGS AND VISIBILITIES REDUCED IN SNOW...BLOWING SNOW
AND FOG WILL CONTINUE ACROSS THE WEST THROUGH 18Z SUNDAY.  LLWS
WILL ALSO PERSIST ACROSS THE AREA AS FL070-100 WINDS BTWN
40-50KTS. A STRONG COLD FRONT WILL PUSH ACROSS THE AREA THIS
AFTERNOON AND EVENING WITH AREAS OF WEST SFC WIND 20-30KTS WITH
GUSTS TO 40KTS. MVFR/IFR CEILINGS AND VISIBILITIES WILL DECREASE
ACROSS THE WEST FROM 12Z THROUGH 18Z SUNDAY.

FIRE WEATHER...

SNOWFALL WILL CONTINUE MOST MOUNTAIN AREAS TONIGHT AND THEN
DECREASE THROUGH SUNDAY AS A COLD FRONT PASSES THROUGH.  STRONG WINDS
WILL CONTINUE EARLY THIS EVENING AND THEN DIMINISH. BEHIND THE
COLD FRONT EARLY SUNDAY...HIGH WINDS MAY DEVELOP IN THE WIND
RIVER BASIN AND NORTHERN JOHNSON COUNTIES AS THESE AREAS FAVOR
STRONGER WINDS IN NORTHWEST FLOW. TEMPERATURES WILL BE COLDER WITH
HIGHER HUMIDITY AND LOW MIXING HEIGHTS WITH POOR SMOKE DISPERSAL.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 6 AM MST SUNDAY WYZ012-013-023-024.

HIGH WIND WARNING FROM 5 AM TO 5 PM MST SUNDAY WYZ010.

&&

$$

UPDATE...AEM
SHORT TERM...C.BAKER
LONG TERM...LIPSON
AVIATION...C.BAKER
FIRE WEATHER...C.BAKER






000
FXUS65 KRIW 230338
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
838 PM MST SAT NOV 22 2014

.UPDATE...SNOW HAS TAPERED OFF OR ENDED BEHIND A COLD FRONT ACROSS
MOST OF WESTERN WYOMING. ANOTHER SHORTWAVE MOVING EAST ACROSS
IDAHO WILL BRING ANOTHER SHOT OF LIGHT TO MODERATE SNOW INTO FAR
WEST WYOMING AFTER MIDNIGHT. CANCELLED WINTER HIGHLIGHTS FOR ALL
AREAS BUT JACKSON HOLE VALLEY...STAR VALLEY AND SURROUNDING
MOUNTAINS WHERE WINTER STORM WARNINGS REMAIN IN EFFECT UNTIL 6 AM
SUNDAY. COLD FRONT HAS ALSO ENDED THE HIGH WIND THREAT ACROSS
CENTRAL WYOMING...SO HIGH WIND WARNINGS WERE CANCELLED. UPGRADED
HIGH WIND WATCH TO A WARNING FOR ONLY NORTHEAST JOHNSON COUNTY ON
SUNDAY. LATEST MODEL RUNS NOT AS BULLISH WITH STRONG WINDS FURTHER
WEST ACROSS THE WIND RIVER BASIN.

&&

.PREV DISCUSSION... /ISSUED 210 PM MST SAT NOV 22 2014/

SHORT TERM...TONIGHT THROUGH SUNDAY

A PACIFIC COLD FRONT APPROACHING WESTERN WYOMING WILL MOVE THROUGH
WESTERN AND CENTRAL WYOMING THROUGH THE NIGHT.  THE SNOW INTENSITIES
WILL DECREASE WITH THE PASSING OF THE COLD FRONT IN THE WESTERN
M0MOUNTAINS.  MOST AREAS EXPERIENCING HIGH WINDS TODAY WILL SEE
WINDS DECREASE AS THEY SHIFT TO THE NORTHWEST. HIGH WIND WATCHES
REMAIN FOR NORTHERN JOHNSON AND THE WIND RIVER BASIN WITH THE
NORTHWEST WINDS AS THESE AREAS FAVOR HIGH WINDS WITH NORTHWEST
WINDS AND COLD AIR ADVECTION. AREAS EAST OF THE CONTINENTAL DIVIDE
CAN EXPECT A QUICK BURST OF SNOWFALL BEHIND THE COLD FRONT WITH
LIGHT ACCUMULATIONS. OVERALL SNOWFALL WILL BE TAPERING OFF
THROUGH THE MORNING WITH SOME LINGERING MOUNTAIN SNOW SHOWERS ON
SUNDAY. TEMPERATURES WILL COOL ABOUT TEN DEGREES FROM TODAY.

LONG TERM...SUNDAY NIGHT THROUGH SATURDAY

BEHIND THE MAIN SHORTWAVE THAT WILL BE SWINGING THROUGH THIS
WEEKEND...A SECONDARY PIECE OF ENERGY WILL BE SLIDING DOWN THE BACK
SIDE OF THE MAIN TROUGH AXIS ACROSS THE CWA FAIRLY QUICKLY AROUND
12Z MONDAY. WITH WEAK ISENTROPIC LIFT IN THE WEST AHEAD OF THIS
SYSTEM AS WELL AS SOME WEAK QG FORCING IN THE SOUTHWEST...KEPT IDEA
OF ANOTHER 3 TO 6 INCHES OF SNOWFALL IN THE WESTERN MTNS SUNDAY INTO
MONDAY ALONG WITH ANOTHER 2 TO 3 INCHES IN THE WESTERN VALLEYS. THE
SNOW INTENSITY WILL BEGIN TO DECREASE MONDAY AFTERNOON. DURING THE
TROUGH PASSAGE...AROUND 12Z MONDAY...THERE WILL BE A BRIEF PERIOD WHEN THE
SNOWFALL SPILLS OVER TO AREAS EAST OF THE DIVIDE WITH THE MOST
SIGNIFICANT SNOWFALL OCCURRING IN THE BIG HORN MTNS WHERE 3 TO 5
INCHES ARE EXPECTED. THE SNOWFALL WILL DECREASE EAST OF THE DIVIDE
IN THE AFTERNOON AS WELL.

THE NEXT ANTICIPATED SNOW EVENT WILL OCCUR WHEN THE JET STREAM
SHIFTS NORTHEAST PLACING THE FASTER NORTHWEST FLOW ALOFT OVER
WYOMING BY 12Z TUESDAY. THIS WILL DRAW IN ADDITIONAL PACIFIC
MOISTURE FROM THE NORTHWEST ALONG WITH ISENTROPIC LIFT OVER WESTERN
WY TUESDAY WITH AN EXTENSIVE AREA OF ISENTROPIC LIFT SHIFTING TO OUR
NORTH OVER MONTANA BY TUESDAY NIGHT. THIS WILL JUSTIFY LIKELY POPS
IN THE WESTERN/BIG HORN MTNS AS WELL AS CHC POPS OVER THE NORTH HALF
OF THE LOWER ELEVATIONS OF THE CWA TUE/TUE NIGHT. THE JET STREAM
WILL THEN SHIFT NORTHEAST OF THE CWA BY WEDNESDAY.

AFTER THIS TIME FRAME...THE MODELS DIVERGE ONCE AGAIN WITH THE EURO
NOW THE MORE OPTIMISTIC MODEL PLACING A RIDGE OVER WY BY THURSDAY
AND THE GFS KEEPING THE DIRTY NORTHWEST FLOW OVER US THROUGH FRIDAY
WHICH IS IRONIC BECAUSE A COUPLE OF DAYS AGO BOTH THESE MODELS
PORTRAYED OPPOSITE SOLNS WITH THE GFS ADVERTISING A BUILDING RIDGE
AND THE EURO A POTENTIAL SNOW EVENT FOR THANKSGIVING. WITH THE
MODELS FLIP FLOPPING AND NO RUN TO RUN CONSISTENCY...ALL WE ARE
GOING TO DO IS INCREASE THE POPS A TAD OVER MAINLY NW WY FOR THE
SECOND HALF OF NEXT WEEK JUST IN CASE A SNOW EVENT DOES TAKE PLACE
DURING THIS TIME FRAME. MORE SPECIFICALLY...THE GFS PULLS IN COLDER
AIR FROM THE NORTHEAST OVER WY WITH MOST OF THE ASCT ISENTROPIC LIFT
FROM THIS ASCT WEATHER DISTURBANCE REMAINING TO OUR NORTH UP IN MT.

BY FRIDAY NIGHT...THE NW FLOW WILL BACK TO THE WEST AS THE RIDGE
FLATTENS. A MINOR DISTURBANCE MOVING THROUGH THE FLATTENING RIDGE
WITH ITS SHARE OF ISENTROPIC LIFT COULD BRING SOME LIGHT SNOW TO THE
FAR WEST SATURDAY.

TEMPERATURES NEXT WEEK WILL DEPEND LARGELY UPON WHETHER THE GFS OR
THE EURO PANS OUT SO KIND OF WENT WITH A BLEND. IN ANY EVENT...TEMPS
WILL BE MUCH MILDER THAN THEY HAVE BEEN DURING THE LAST COUPLE OF
WEEKS GIVEN THE LACK OF ANY ARCTIC INTRUSIONS NEXT WEEK.

AVIATION.../00Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES

AREAS OF LLWS WILL CONTINUE OVER THE CENTRAL BASINS AS WEST WINDS
FL070-100 BETWEEN 45-50KTS THROUGH 06Z. THESE STRONGER WINDS WILL
MIX DOWN TO THE SURFACE FROM VCNTY 50NE SM KRKS-KCPR AND FROM
VCNTY KCOD- KDUB WHERE HIGH WIND WARNINGS ARE IN EFFECT. A STRONG
COLD FRONT WILL PUSH ACROSS THE AREA EARLY THIS EVENING. MTNS WILL
BE MOSTLY OBSCURED ALONG THE DIVIDE AHEAD OF THE FRONT WITH SOME
BLOW OVER PCPN IN THE VCNTY OF KLND-KCOD. A BAND OF SNOW WILL
LIKELY ACCOMPANY THE FRONT THIS EVENING ALONG WITH AREAS OF
MVFR/IFR -SN MAINLY VCNTY ALONG AND EAST OF THE BIGHORN RANGE AND
INTERSTATE 25. AREAS OF SFC NW WINDS AT 20-30KTS WITH GUSTS TO
40KTS WILL FOLLOW THE FRONT...DECREASING AFTER 06Z.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES

MVFR/IFR CEILINGS AND VISIBILITIES REDUCED IN SNOW...BLOWING SNOW
AND FOG WILL CONTINUE ACROSS THE WEST THROUGH 18Z SUNDAY.  LLWS
WILL ALSO PERSIST ACROSS THE AREA AS FL070-100 WINDS BTWN
40-50KTS. A STRONG COLD FRONT WILL PUSH ACROSS THE AREA THIS
AFTERNOON AND EVENING WITH AREAS OF WEST SFC WIND 20-30KTS WITH
GUSTS TO 40KTS. MVFR/IFR CEILINGS AND VISIBILITIES WILL DECREASE
ACROSS THE WEST FROM 12Z THROUGH 18Z SUNDAY.

FIRE WEATHER...

SNOWFALL WILL CONTINUE MOST MOUNTAIN AREAS TONIGHT AND THEN
DECREASE THROUGH SUNDAY AS A COLD FRONT PASSES THROUGH.  STRONG WINDS
WILL CONTINUE EARLY THIS EVENING AND THEN DIMINISH. BEHIND THE
COLD FRONT EARLY SUNDAY...HIGH WINDS MAY DEVELOP IN THE WIND
RIVER BASIN AND NORTHERN JOHNSON COUNTIES AS THESE AREAS FAVOR
STRONGER WINDS IN NORTHWEST FLOW. TEMPERATURES WILL BE COLDER WITH
HIGHER HUMIDITY AND LOW MIXING HEIGHTS WITH POOR SMOKE DISPERSAL.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 6 AM MST SUNDAY WYZ012-013-023-024.

HIGH WIND WARNING FROM 5 AM TO 5 PM MST SUNDAY WYZ010.

&&

$$

UPDATE...AEM
SHORT TERM...C.BAKER
LONG TERM...LIPSON
AVIATION...C.BAKER
FIRE WEATHER...C.BAKER





000
FXUS65 KRIW 230338
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
838 PM MST SAT NOV 22 2014

.UPDATE...SNOW HAS TAPERED OFF OR ENDED BEHIND A COLD FRONT ACROSS
MOST OF WESTERN WYOMING. ANOTHER SHORTWAVE MOVING EAST ACROSS
IDAHO WILL BRING ANOTHER SHOT OF LIGHT TO MODERATE SNOW INTO FAR
WEST WYOMING AFTER MIDNIGHT. CANCELLED WINTER HIGHLIGHTS FOR ALL
AREAS BUT JACKSON HOLE VALLEY...STAR VALLEY AND SURROUNDING
MOUNTAINS WHERE WINTER STORM WARNINGS REMAIN IN EFFECT UNTIL 6 AM
SUNDAY. COLD FRONT HAS ALSO ENDED THE HIGH WIND THREAT ACROSS
CENTRAL WYOMING...SO HIGH WIND WARNINGS WERE CANCELLED. UPGRADED
HIGH WIND WATCH TO A WARNING FOR ONLY NORTHEAST JOHNSON COUNTY ON
SUNDAY. LATEST MODEL RUNS NOT AS BULLISH WITH STRONG WINDS FURTHER
WEST ACROSS THE WIND RIVER BASIN.

&&

.PREV DISCUSSION... /ISSUED 210 PM MST SAT NOV 22 2014/

SHORT TERM...TONIGHT THROUGH SUNDAY

A PACIFIC COLD FRONT APPROACHING WESTERN WYOMING WILL MOVE THROUGH
WESTERN AND CENTRAL WYOMING THROUGH THE NIGHT.  THE SNOW INTENSITIES
WILL DECREASE WITH THE PASSING OF THE COLD FRONT IN THE WESTERN
M0MOUNTAINS.  MOST AREAS EXPERIENCING HIGH WINDS TODAY WILL SEE
WINDS DECREASE AS THEY SHIFT TO THE NORTHWEST. HIGH WIND WATCHES
REMAIN FOR NORTHERN JOHNSON AND THE WIND RIVER BASIN WITH THE
NORTHWEST WINDS AS THESE AREAS FAVOR HIGH WINDS WITH NORTHWEST
WINDS AND COLD AIR ADVECTION. AREAS EAST OF THE CONTINENTAL DIVIDE
CAN EXPECT A QUICK BURST OF SNOWFALL BEHIND THE COLD FRONT WITH
LIGHT ACCUMULATIONS. OVERALL SNOWFALL WILL BE TAPERING OFF
THROUGH THE MORNING WITH SOME LINGERING MOUNTAIN SNOW SHOWERS ON
SUNDAY. TEMPERATURES WILL COOL ABOUT TEN DEGREES FROM TODAY.

LONG TERM...SUNDAY NIGHT THROUGH SATURDAY

BEHIND THE MAIN SHORTWAVE THAT WILL BE SWINGING THROUGH THIS
WEEKEND...A SECONDARY PIECE OF ENERGY WILL BE SLIDING DOWN THE BACK
SIDE OF THE MAIN TROUGH AXIS ACROSS THE CWA FAIRLY QUICKLY AROUND
12Z MONDAY. WITH WEAK ISENTROPIC LIFT IN THE WEST AHEAD OF THIS
SYSTEM AS WELL AS SOME WEAK QG FORCING IN THE SOUTHWEST...KEPT IDEA
OF ANOTHER 3 TO 6 INCHES OF SNOWFALL IN THE WESTERN MTNS SUNDAY INTO
MONDAY ALONG WITH ANOTHER 2 TO 3 INCHES IN THE WESTERN VALLEYS. THE
SNOW INTENSITY WILL BEGIN TO DECREASE MONDAY AFTERNOON. DURING THE
TROUGH PASSAGE...AROUND 12Z MONDAY...THERE WILL BE A BRIEF PERIOD WHEN THE
SNOWFALL SPILLS OVER TO AREAS EAST OF THE DIVIDE WITH THE MOST
SIGNIFICANT SNOWFALL OCCURRING IN THE BIG HORN MTNS WHERE 3 TO 5
INCHES ARE EXPECTED. THE SNOWFALL WILL DECREASE EAST OF THE DIVIDE
IN THE AFTERNOON AS WELL.

THE NEXT ANTICIPATED SNOW EVENT WILL OCCUR WHEN THE JET STREAM
SHIFTS NORTHEAST PLACING THE FASTER NORTHWEST FLOW ALOFT OVER
WYOMING BY 12Z TUESDAY. THIS WILL DRAW IN ADDITIONAL PACIFIC
MOISTURE FROM THE NORTHWEST ALONG WITH ISENTROPIC LIFT OVER WESTERN
WY TUESDAY WITH AN EXTENSIVE AREA OF ISENTROPIC LIFT SHIFTING TO OUR
NORTH OVER MONTANA BY TUESDAY NIGHT. THIS WILL JUSTIFY LIKELY POPS
IN THE WESTERN/BIG HORN MTNS AS WELL AS CHC POPS OVER THE NORTH HALF
OF THE LOWER ELEVATIONS OF THE CWA TUE/TUE NIGHT. THE JET STREAM
WILL THEN SHIFT NORTHEAST OF THE CWA BY WEDNESDAY.

AFTER THIS TIME FRAME...THE MODELS DIVERGE ONCE AGAIN WITH THE EURO
NOW THE MORE OPTIMISTIC MODEL PLACING A RIDGE OVER WY BY THURSDAY
AND THE GFS KEEPING THE DIRTY NORTHWEST FLOW OVER US THROUGH FRIDAY
WHICH IS IRONIC BECAUSE A COUPLE OF DAYS AGO BOTH THESE MODELS
PORTRAYED OPPOSITE SOLNS WITH THE GFS ADVERTISING A BUILDING RIDGE
AND THE EURO A POTENTIAL SNOW EVENT FOR THANKSGIVING. WITH THE
MODELS FLIP FLOPPING AND NO RUN TO RUN CONSISTENCY...ALL WE ARE
GOING TO DO IS INCREASE THE POPS A TAD OVER MAINLY NW WY FOR THE
SECOND HALF OF NEXT WEEK JUST IN CASE A SNOW EVENT DOES TAKE PLACE
DURING THIS TIME FRAME. MORE SPECIFICALLY...THE GFS PULLS IN COLDER
AIR FROM THE NORTHEAST OVER WY WITH MOST OF THE ASCT ISENTROPIC LIFT
FROM THIS ASCT WEATHER DISTURBANCE REMAINING TO OUR NORTH UP IN MT.

BY FRIDAY NIGHT...THE NW FLOW WILL BACK TO THE WEST AS THE RIDGE
FLATTENS. A MINOR DISTURBANCE MOVING THROUGH THE FLATTENING RIDGE
WITH ITS SHARE OF ISENTROPIC LIFT COULD BRING SOME LIGHT SNOW TO THE
FAR WEST SATURDAY.

TEMPERATURES NEXT WEEK WILL DEPEND LARGELY UPON WHETHER THE GFS OR
THE EURO PANS OUT SO KIND OF WENT WITH A BLEND. IN ANY EVENT...TEMPS
WILL BE MUCH MILDER THAN THEY HAVE BEEN DURING THE LAST COUPLE OF
WEEKS GIVEN THE LACK OF ANY ARCTIC INTRUSIONS NEXT WEEK.

AVIATION.../00Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES

AREAS OF LLWS WILL CONTINUE OVER THE CENTRAL BASINS AS WEST WINDS
FL070-100 BETWEEN 45-50KTS THROUGH 06Z. THESE STRONGER WINDS WILL
MIX DOWN TO THE SURFACE FROM VCNTY 50NE SM KRKS-KCPR AND FROM
VCNTY KCOD- KDUB WHERE HIGH WIND WARNINGS ARE IN EFFECT. A STRONG
COLD FRONT WILL PUSH ACROSS THE AREA EARLY THIS EVENING. MTNS WILL
BE MOSTLY OBSCURED ALONG THE DIVIDE AHEAD OF THE FRONT WITH SOME
BLOW OVER PCPN IN THE VCNTY OF KLND-KCOD. A BAND OF SNOW WILL
LIKELY ACCOMPANY THE FRONT THIS EVENING ALONG WITH AREAS OF
MVFR/IFR -SN MAINLY VCNTY ALONG AND EAST OF THE BIGHORN RANGE AND
INTERSTATE 25. AREAS OF SFC NW WINDS AT 20-30KTS WITH GUSTS TO
40KTS WILL FOLLOW THE FRONT...DECREASING AFTER 06Z.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES

MVFR/IFR CEILINGS AND VISIBILITIES REDUCED IN SNOW...BLOWING SNOW
AND FOG WILL CONTINUE ACROSS THE WEST THROUGH 18Z SUNDAY.  LLWS
WILL ALSO PERSIST ACROSS THE AREA AS FL070-100 WINDS BTWN
40-50KTS. A STRONG COLD FRONT WILL PUSH ACROSS THE AREA THIS
AFTERNOON AND EVENING WITH AREAS OF WEST SFC WIND 20-30KTS WITH
GUSTS TO 40KTS. MVFR/IFR CEILINGS AND VISIBILITIES WILL DECREASE
ACROSS THE WEST FROM 12Z THROUGH 18Z SUNDAY.

FIRE WEATHER...

SNOWFALL WILL CONTINUE MOST MOUNTAIN AREAS TONIGHT AND THEN
DECREASE THROUGH SUNDAY AS A COLD FRONT PASSES THROUGH.  STRONG WINDS
WILL CONTINUE EARLY THIS EVENING AND THEN DIMINISH. BEHIND THE
COLD FRONT EARLY SUNDAY...HIGH WINDS MAY DEVELOP IN THE WIND
RIVER BASIN AND NORTHERN JOHNSON COUNTIES AS THESE AREAS FAVOR
STRONGER WINDS IN NORTHWEST FLOW. TEMPERATURES WILL BE COLDER WITH
HIGHER HUMIDITY AND LOW MIXING HEIGHTS WITH POOR SMOKE DISPERSAL.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 6 AM MST SUNDAY WYZ012-013-023-024.

HIGH WIND WARNING FROM 5 AM TO 5 PM MST SUNDAY WYZ010.

&&

$$

UPDATE...AEM
SHORT TERM...C.BAKER
LONG TERM...LIPSON
AVIATION...C.BAKER
FIRE WEATHER...C.BAKER






000
FXUS65 KRIW 230338
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
838 PM MST SAT NOV 22 2014

.UPDATE...SNOW HAS TAPERED OFF OR ENDED BEHIND A COLD FRONT ACROSS
MOST OF WESTERN WYOMING. ANOTHER SHORTWAVE MOVING EAST ACROSS
IDAHO WILL BRING ANOTHER SHOT OF LIGHT TO MODERATE SNOW INTO FAR
WEST WYOMING AFTER MIDNIGHT. CANCELLED WINTER HIGHLIGHTS FOR ALL
AREAS BUT JACKSON HOLE VALLEY...STAR VALLEY AND SURROUNDING
MOUNTAINS WHERE WINTER STORM WARNINGS REMAIN IN EFFECT UNTIL 6 AM
SUNDAY. COLD FRONT HAS ALSO ENDED THE HIGH WIND THREAT ACROSS
CENTRAL WYOMING...SO HIGH WIND WARNINGS WERE CANCELLED. UPGRADED
HIGH WIND WATCH TO A WARNING FOR ONLY NORTHEAST JOHNSON COUNTY ON
SUNDAY. LATEST MODEL RUNS NOT AS BULLISH WITH STRONG WINDS FURTHER
WEST ACROSS THE WIND RIVER BASIN.

&&

.PREV DISCUSSION... /ISSUED 210 PM MST SAT NOV 22 2014/

SHORT TERM...TONIGHT THROUGH SUNDAY

A PACIFIC COLD FRONT APPROACHING WESTERN WYOMING WILL MOVE THROUGH
WESTERN AND CENTRAL WYOMING THROUGH THE NIGHT.  THE SNOW INTENSITIES
WILL DECREASE WITH THE PASSING OF THE COLD FRONT IN THE WESTERN
M0MOUNTAINS.  MOST AREAS EXPERIENCING HIGH WINDS TODAY WILL SEE
WINDS DECREASE AS THEY SHIFT TO THE NORTHWEST. HIGH WIND WATCHES
REMAIN FOR NORTHERN JOHNSON AND THE WIND RIVER BASIN WITH THE
NORTHWEST WINDS AS THESE AREAS FAVOR HIGH WINDS WITH NORTHWEST
WINDS AND COLD AIR ADVECTION. AREAS EAST OF THE CONTINENTAL DIVIDE
CAN EXPECT A QUICK BURST OF SNOWFALL BEHIND THE COLD FRONT WITH
LIGHT ACCUMULATIONS. OVERALL SNOWFALL WILL BE TAPERING OFF
THROUGH THE MORNING WITH SOME LINGERING MOUNTAIN SNOW SHOWERS ON
SUNDAY. TEMPERATURES WILL COOL ABOUT TEN DEGREES FROM TODAY.

LONG TERM...SUNDAY NIGHT THROUGH SATURDAY

BEHIND THE MAIN SHORTWAVE THAT WILL BE SWINGING THROUGH THIS
WEEKEND...A SECONDARY PIECE OF ENERGY WILL BE SLIDING DOWN THE BACK
SIDE OF THE MAIN TROUGH AXIS ACROSS THE CWA FAIRLY QUICKLY AROUND
12Z MONDAY. WITH WEAK ISENTROPIC LIFT IN THE WEST AHEAD OF THIS
SYSTEM AS WELL AS SOME WEAK QG FORCING IN THE SOUTHWEST...KEPT IDEA
OF ANOTHER 3 TO 6 INCHES OF SNOWFALL IN THE WESTERN MTNS SUNDAY INTO
MONDAY ALONG WITH ANOTHER 2 TO 3 INCHES IN THE WESTERN VALLEYS. THE
SNOW INTENSITY WILL BEGIN TO DECREASE MONDAY AFTERNOON. DURING THE
TROUGH PASSAGE...AROUND 12Z MONDAY...THERE WILL BE A BRIEF PERIOD WHEN THE
SNOWFALL SPILLS OVER TO AREAS EAST OF THE DIVIDE WITH THE MOST
SIGNIFICANT SNOWFALL OCCURRING IN THE BIG HORN MTNS WHERE 3 TO 5
INCHES ARE EXPECTED. THE SNOWFALL WILL DECREASE EAST OF THE DIVIDE
IN THE AFTERNOON AS WELL.

THE NEXT ANTICIPATED SNOW EVENT WILL OCCUR WHEN THE JET STREAM
SHIFTS NORTHEAST PLACING THE FASTER NORTHWEST FLOW ALOFT OVER
WYOMING BY 12Z TUESDAY. THIS WILL DRAW IN ADDITIONAL PACIFIC
MOISTURE FROM THE NORTHWEST ALONG WITH ISENTROPIC LIFT OVER WESTERN
WY TUESDAY WITH AN EXTENSIVE AREA OF ISENTROPIC LIFT SHIFTING TO OUR
NORTH OVER MONTANA BY TUESDAY NIGHT. THIS WILL JUSTIFY LIKELY POPS
IN THE WESTERN/BIG HORN MTNS AS WELL AS CHC POPS OVER THE NORTH HALF
OF THE LOWER ELEVATIONS OF THE CWA TUE/TUE NIGHT. THE JET STREAM
WILL THEN SHIFT NORTHEAST OF THE CWA BY WEDNESDAY.

AFTER THIS TIME FRAME...THE MODELS DIVERGE ONCE AGAIN WITH THE EURO
NOW THE MORE OPTIMISTIC MODEL PLACING A RIDGE OVER WY BY THURSDAY
AND THE GFS KEEPING THE DIRTY NORTHWEST FLOW OVER US THROUGH FRIDAY
WHICH IS IRONIC BECAUSE A COUPLE OF DAYS AGO BOTH THESE MODELS
PORTRAYED OPPOSITE SOLNS WITH THE GFS ADVERTISING A BUILDING RIDGE
AND THE EURO A POTENTIAL SNOW EVENT FOR THANKSGIVING. WITH THE
MODELS FLIP FLOPPING AND NO RUN TO RUN CONSISTENCY...ALL WE ARE
GOING TO DO IS INCREASE THE POPS A TAD OVER MAINLY NW WY FOR THE
SECOND HALF OF NEXT WEEK JUST IN CASE A SNOW EVENT DOES TAKE PLACE
DURING THIS TIME FRAME. MORE SPECIFICALLY...THE GFS PULLS IN COLDER
AIR FROM THE NORTHEAST OVER WY WITH MOST OF THE ASCT ISENTROPIC LIFT
FROM THIS ASCT WEATHER DISTURBANCE REMAINING TO OUR NORTH UP IN MT.

BY FRIDAY NIGHT...THE NW FLOW WILL BACK TO THE WEST AS THE RIDGE
FLATTENS. A MINOR DISTURBANCE MOVING THROUGH THE FLATTENING RIDGE
WITH ITS SHARE OF ISENTROPIC LIFT COULD BRING SOME LIGHT SNOW TO THE
FAR WEST SATURDAY.

TEMPERATURES NEXT WEEK WILL DEPEND LARGELY UPON WHETHER THE GFS OR
THE EURO PANS OUT SO KIND OF WENT WITH A BLEND. IN ANY EVENT...TEMPS
WILL BE MUCH MILDER THAN THEY HAVE BEEN DURING THE LAST COUPLE OF
WEEKS GIVEN THE LACK OF ANY ARCTIC INTRUSIONS NEXT WEEK.

AVIATION.../00Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES

AREAS OF LLWS WILL CONTINUE OVER THE CENTRAL BASINS AS WEST WINDS
FL070-100 BETWEEN 45-50KTS THROUGH 06Z. THESE STRONGER WINDS WILL
MIX DOWN TO THE SURFACE FROM VCNTY 50NE SM KRKS-KCPR AND FROM
VCNTY KCOD- KDUB WHERE HIGH WIND WARNINGS ARE IN EFFECT. A STRONG
COLD FRONT WILL PUSH ACROSS THE AREA EARLY THIS EVENING. MTNS WILL
BE MOSTLY OBSCURED ALONG THE DIVIDE AHEAD OF THE FRONT WITH SOME
BLOW OVER PCPN IN THE VCNTY OF KLND-KCOD. A BAND OF SNOW WILL
LIKELY ACCOMPANY THE FRONT THIS EVENING ALONG WITH AREAS OF
MVFR/IFR -SN MAINLY VCNTY ALONG AND EAST OF THE BIGHORN RANGE AND
INTERSTATE 25. AREAS OF SFC NW WINDS AT 20-30KTS WITH GUSTS TO
40KTS WILL FOLLOW THE FRONT...DECREASING AFTER 06Z.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES

MVFR/IFR CEILINGS AND VISIBILITIES REDUCED IN SNOW...BLOWING SNOW
AND FOG WILL CONTINUE ACROSS THE WEST THROUGH 18Z SUNDAY.  LLWS
WILL ALSO PERSIST ACROSS THE AREA AS FL070-100 WINDS BTWN
40-50KTS. A STRONG COLD FRONT WILL PUSH ACROSS THE AREA THIS
AFTERNOON AND EVENING WITH AREAS OF WEST SFC WIND 20-30KTS WITH
GUSTS TO 40KTS. MVFR/IFR CEILINGS AND VISIBILITIES WILL DECREASE
ACROSS THE WEST FROM 12Z THROUGH 18Z SUNDAY.

FIRE WEATHER...

SNOWFALL WILL CONTINUE MOST MOUNTAIN AREAS TONIGHT AND THEN
DECREASE THROUGH SUNDAY AS A COLD FRONT PASSES THROUGH.  STRONG WINDS
WILL CONTINUE EARLY THIS EVENING AND THEN DIMINISH. BEHIND THE
COLD FRONT EARLY SUNDAY...HIGH WINDS MAY DEVELOP IN THE WIND
RIVER BASIN AND NORTHERN JOHNSON COUNTIES AS THESE AREAS FAVOR
STRONGER WINDS IN NORTHWEST FLOW. TEMPERATURES WILL BE COLDER WITH
HIGHER HUMIDITY AND LOW MIXING HEIGHTS WITH POOR SMOKE DISPERSAL.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 6 AM MST SUNDAY WYZ012-013-023-024.

HIGH WIND WARNING FROM 5 AM TO 5 PM MST SUNDAY WYZ010.

&&

$$

UPDATE...AEM
SHORT TERM...C.BAKER
LONG TERM...LIPSON
AVIATION...C.BAKER
FIRE WEATHER...C.BAKER





000
FXUS65 KCYS 230000
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
500 PM MST SAT NOV 22 2014

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM MST SAT NOV 22 2014

PRIMARY CONCERNS THROUGH THIS WEEKEND WILL BE WINDS AND MOUNTAIN
SNOWFALL. MOST OF THE AREA WITHIN THE HIGH WIND WARNING HAS
VERIFIED THIS AFTERNOON WITH GUSTS AS HIGH AS 76 MPH REPORTED
ALONG I25 AND I80. ELSEWHERE...WINDS HAVE STRUGGLED ACROSS
LOCATIONS SUCH AS THE LARAMIE VALLEY AND THE HIGH PLAINS
IMMEDIATELY EAST OF THE LARAMIE RANGE. BELIEVE THIS IS DUE TO A
COMBINATION OF CLOUDY SKIES AND AN AREA OF POSITIVE OMEGA EAST OF
THE MOUNTAINS. WILL KEEP THE HIGH WIND WARNING OUT FOR THESE
AREAS...BUT THERE IS ONLY A SMALL WINDOW TO SEE GUSTS AROUND 55
MPH SINCE DOWNSLOPE AND SUBSIDENCE WILL BEGIN TO DIMINISH BY LATE
THIS EVENING. ENDED THE HIGH WIND WARNING AT MIDNIGHT TONIGHT
SINCE THE FRONT AND IS TRENDING A BIT FASTER AND SHOULD BE NEAR
THE COLORADO BORDER A FEW HOURS BEFORE MIDNIGHT. AFTER THE FRONT
AND ASSOCIATED TROUGH AXIS ALOFT MOVES THROUGH...WINDS WILL SHIFT
INTO THE NORTHWEST WHICH WILL END THE HIGH WIND EVENT BRIEFLY FOR
THE WIND PRONE AREAS AS WELL. HOWEVER...HIGH WINDS WILL LIKELY
RETURN BY LATE MONDAY NIGHT ACROSS MOST OF SOUTHEAST WYOMING.

SNOW WILL BE ANOTHER CONCERN...PRIMARILY ACROSS THE MOUNTAINS OF
SOUTHEAST WYOMING AND PERHAPS EVEN SOME OF THE HIGH VALLEYS. SNOW
IS DEVELOPING ACROSS THE MOUNTAINS EARLY THIS AFTERNOON WITH SOME
RAIN/SNOW MIX DOWN TO THE VALLEY FLOORS. ANY RAINFALL WILL QUICKLY
CHANGE TO SNOW LATE THIS AFTERNOON AS MUCH COLDER AIR MOVES INTO
THE AREA. THE HEAVIEST SNOW WILL BE TONIGHT...BUT ANOTHER
DISTURBANCE ALOFT WILL PUSH ACROSS THE AREA ON SUNDAY AS WELL
RESULTING IN SOME ENHANCEMENT OF SNOWFALL RATES. HIGH CONFIDENCE
THAT THE MOUNTAINS WILL DO WELL WITH THIS EVENT...SO KEPT THE
WINTER STORM WARNING GOING THROUGH MONDAY FOR 1 TO 2 FEET OF SNOW.
EXPECT THE PRECIPITATION TO BE ENHANCED FURTHER ON THE WEST TO
NORTHWEST FACING SLOPES AND RIDGES DUE TO UPSLOPE FLOW. FOR THE
VALLEYS AND HIGH PLAINS...EXPECT PERHAPS 1 TO 2 INCHES ALONG I80
WEST OF THE LARAMIE RANGE AND FURTHER NORTH ALONG I80 AROUND
DOUGLAS. THE CHEYENNE RIDGE FROM CHEYENNE TO SIDNEY INCLUDING MOST
OF THE NEBRASKA PANHANDLE WILL BE LUCKY TO SEE A DUSTING OF SNOW
DUE TO THE LARGE LOW LEVEL DOWNSLOPE COMPONENT TO THE WINDS. THE
BEST CHANCE TO SEE SOME SNOW WILL BE NEAR THE FRONTAL PASSAGE DUE
TO BRIEF FRONTOGENESIS AND LOW LEVEL DYNAMIC LIFT. THERE IS SOME
CONCERN THAT THE ADJACENT VALLEYS ACROSS SOUTHERN CARBON COUNTY
WILL SEE SOME MODERATE SNOWFALL RATES AS THE WINDS SHIFT INTO THE
NORTHWEST. WILL CONTINUE TO KEEP AN EYE ON THIS THROUGH SUNDAY AS
THE NEXT DISTURBANCE MOVES ACROSS THE AREA. FOR NOW...KEPT 1 TO 3
INCHES OF SNOW IN THESE LOCATIONS WITH 5 INCHES POSSIBLE LOCALLY.

FOR MONDAY...ANOTHER DISTURBANCE ALOFT WILL MOVE ACROSS THE
AREA...RESULTING IN ENHANCED SNOWFALL RATES ACROSS THE MOUNTAINS
AFTER A BRIEF LULL SUNDAY NIGHT. THIS MAY BE THE BEST CHANCE FOR
THE HIGH PLAINS TO RECEIVE SOME WIDESPREAD LIGHT SNOW
ACCUMULATIONS AS WINDS SHIFT INTO THE NORTH.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 300 PM MST SAT NOV 22 2014

STRONG WINDS CONTINUE THROUGH AT LEAST WEDNESDAY. GFS SHOWING A
1041MB SURFACE HIGH OVER WESTERN COLORADO TUESDAY MORNING WITH
A ROUGHLY 10-12MB SURFACE GRADIENT BETWEEN CASPER AND CRAIG.
700MB WINDS FROM THE NORTHWEST AT 50-60KTS WITH A 700MB HEIGHT
GRADIENT AROUND 70 TO 80 MARS BETWEEN CRAIG AND CASPER. ALMOST A
SURE THING FOR WIND WARNING CRITERIA AT LEAST FOR THE WIND PRONE
AREAS AND HAVE BUMPED UP GUIDANCE AT THESE LOCATIONS TO REFLECT
CONFIDENCE IN HIGH WINDS.

WINDS LOOK TO FINALLY EASE SOME THURSDAY AS WE SEE A FRONT DIVE
SOUTHWEST OUT OF THE DAKOTAS AND LAY UP AGAINST THE LARAMIE RANGE.
ECMWF A LITTLE FURTHER NORTHEAST WITH THIS FRONT OVER THE MORE
AGGRESSIVE GFS...FINALLY PUSHING THE BOUNDARY INTO THE LARAMIE
RANGE THURSDAY EVENING. DID GO AHEAD AND LOWER TEMPERATURES SOME
OVER THE NORTHERN PANHANDLE AND OUR EASTERN ZONES TO REFLECT THE
MUCH COLDER AIR BEHIND THE FRONT FOR THURSDAY THROUGH FRIDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 453 PM MST SAT NOV 22 2014

STRONG AND GUSTY WESTERLY WINDS WILL CONTINUE TONIGHT WITH
THE PASSAGE OF A PACIFIC COLD FRONT. GUSTS TO 50 KT WILL
STILL BE POSSIBLE EARLY THIS EVENING...MAINLY INVOF THE
MOUNTAINS. GUSTS WILL DECREASE TO 30-40 KT LATER THIS EVENING
AND OVERNIGHT. MVFR CONDITIONS IN RAIN/SNOW SHOWERS WEST OF THE
LARAMIE RANGE WILL SPREAD EAST ONTO THE PLAINS TONIGHT...WITH
OCCASIONAL IFR POSSIBLE. PRECIPITATION WILL TAPER OFF WITH
IMPROVING CIGS/VSBYS SUNDAY MORNING.

&&

.FIRE WEATHER...
ISSUED AT 209 PM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG THROUGH EARLY NEXT WEEK...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED DUE TO COOL TEMPERATURES AND HIGH
RELATIVE HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...HIGH WIND WARNING UNTIL MIDNIGHT MST TONIGHT FOR WYZ101-103>107-
     110-115>118.

     WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ112-114.

NE...WIND ADVISORY FROM 9 AM TO 6 PM MST SUNDAY FOR NEZ002-003-
     019>021-054-055-095-096.

&&

$$

SHORT TERM...TJT
LONG TERM...GCC
AVIATION...MJ
FIRE WEATHER...TJT




000
FXUS65 KCYS 230000
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
500 PM MST SAT NOV 22 2014

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM MST SAT NOV 22 2014

PRIMARY CONCERNS THROUGH THIS WEEKEND WILL BE WINDS AND MOUNTAIN
SNOWFALL. MOST OF THE AREA WITHIN THE HIGH WIND WARNING HAS
VERIFIED THIS AFTERNOON WITH GUSTS AS HIGH AS 76 MPH REPORTED
ALONG I25 AND I80. ELSEWHERE...WINDS HAVE STRUGGLED ACROSS
LOCATIONS SUCH AS THE LARAMIE VALLEY AND THE HIGH PLAINS
IMMEDIATELY EAST OF THE LARAMIE RANGE. BELIEVE THIS IS DUE TO A
COMBINATION OF CLOUDY SKIES AND AN AREA OF POSITIVE OMEGA EAST OF
THE MOUNTAINS. WILL KEEP THE HIGH WIND WARNING OUT FOR THESE
AREAS...BUT THERE IS ONLY A SMALL WINDOW TO SEE GUSTS AROUND 55
MPH SINCE DOWNSLOPE AND SUBSIDENCE WILL BEGIN TO DIMINISH BY LATE
THIS EVENING. ENDED THE HIGH WIND WARNING AT MIDNIGHT TONIGHT
SINCE THE FRONT AND IS TRENDING A BIT FASTER AND SHOULD BE NEAR
THE COLORADO BORDER A FEW HOURS BEFORE MIDNIGHT. AFTER THE FRONT
AND ASSOCIATED TROUGH AXIS ALOFT MOVES THROUGH...WINDS WILL SHIFT
INTO THE NORTHWEST WHICH WILL END THE HIGH WIND EVENT BRIEFLY FOR
THE WIND PRONE AREAS AS WELL. HOWEVER...HIGH WINDS WILL LIKELY
RETURN BY LATE MONDAY NIGHT ACROSS MOST OF SOUTHEAST WYOMING.

SNOW WILL BE ANOTHER CONCERN...PRIMARILY ACROSS THE MOUNTAINS OF
SOUTHEAST WYOMING AND PERHAPS EVEN SOME OF THE HIGH VALLEYS. SNOW
IS DEVELOPING ACROSS THE MOUNTAINS EARLY THIS AFTERNOON WITH SOME
RAIN/SNOW MIX DOWN TO THE VALLEY FLOORS. ANY RAINFALL WILL QUICKLY
CHANGE TO SNOW LATE THIS AFTERNOON AS MUCH COLDER AIR MOVES INTO
THE AREA. THE HEAVIEST SNOW WILL BE TONIGHT...BUT ANOTHER
DISTURBANCE ALOFT WILL PUSH ACROSS THE AREA ON SUNDAY AS WELL
RESULTING IN SOME ENHANCEMENT OF SNOWFALL RATES. HIGH CONFIDENCE
THAT THE MOUNTAINS WILL DO WELL WITH THIS EVENT...SO KEPT THE
WINTER STORM WARNING GOING THROUGH MONDAY FOR 1 TO 2 FEET OF SNOW.
EXPECT THE PRECIPITATION TO BE ENHANCED FURTHER ON THE WEST TO
NORTHWEST FACING SLOPES AND RIDGES DUE TO UPSLOPE FLOW. FOR THE
VALLEYS AND HIGH PLAINS...EXPECT PERHAPS 1 TO 2 INCHES ALONG I80
WEST OF THE LARAMIE RANGE AND FURTHER NORTH ALONG I80 AROUND
DOUGLAS. THE CHEYENNE RIDGE FROM CHEYENNE TO SIDNEY INCLUDING MOST
OF THE NEBRASKA PANHANDLE WILL BE LUCKY TO SEE A DUSTING OF SNOW
DUE TO THE LARGE LOW LEVEL DOWNSLOPE COMPONENT TO THE WINDS. THE
BEST CHANCE TO SEE SOME SNOW WILL BE NEAR THE FRONTAL PASSAGE DUE
TO BRIEF FRONTOGENESIS AND LOW LEVEL DYNAMIC LIFT. THERE IS SOME
CONCERN THAT THE ADJACENT VALLEYS ACROSS SOUTHERN CARBON COUNTY
WILL SEE SOME MODERATE SNOWFALL RATES AS THE WINDS SHIFT INTO THE
NORTHWEST. WILL CONTINUE TO KEEP AN EYE ON THIS THROUGH SUNDAY AS
THE NEXT DISTURBANCE MOVES ACROSS THE AREA. FOR NOW...KEPT 1 TO 3
INCHES OF SNOW IN THESE LOCATIONS WITH 5 INCHES POSSIBLE LOCALLY.

FOR MONDAY...ANOTHER DISTURBANCE ALOFT WILL MOVE ACROSS THE
AREA...RESULTING IN ENHANCED SNOWFALL RATES ACROSS THE MOUNTAINS
AFTER A BRIEF LULL SUNDAY NIGHT. THIS MAY BE THE BEST CHANCE FOR
THE HIGH PLAINS TO RECEIVE SOME WIDESPREAD LIGHT SNOW
ACCUMULATIONS AS WINDS SHIFT INTO THE NORTH.

.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 300 PM MST SAT NOV 22 2014

STRONG WINDS CONTINUE THROUGH AT LEAST WEDNESDAY. GFS SHOWING A
1041MB SURFACE HIGH OVER WESTERN COLORADO TUESDAY MORNING WITH
A ROUGHLY 10-12MB SURFACE GRADIENT BETWEEN CASPER AND CRAIG.
700MB WINDS FROM THE NORTHWEST AT 50-60KTS WITH A 700MB HEIGHT
GRADIENT AROUND 70 TO 80 MARS BETWEEN CRAIG AND CASPER. ALMOST A
SURE THING FOR WIND WARNING CRITERIA AT LEAST FOR THE WIND PRONE
AREAS AND HAVE BUMPED UP GUIDANCE AT THESE LOCATIONS TO REFLECT
CONFIDENCE IN HIGH WINDS.

WINDS LOOK TO FINALLY EASE SOME THURSDAY AS WE SEE A FRONT DIVE
SOUTHWEST OUT OF THE DAKOTAS AND LAY UP AGAINST THE LARAMIE RANGE.
ECMWF A LITTLE FURTHER NORTHEAST WITH THIS FRONT OVER THE MORE
AGGRESSIVE GFS...FINALLY PUSHING THE BOUNDARY INTO THE LARAMIE
RANGE THURSDAY EVENING. DID GO AHEAD AND LOWER TEMPERATURES SOME
OVER THE NORTHERN PANHANDLE AND OUR EASTERN ZONES TO REFLECT THE
MUCH COLDER AIR BEHIND THE FRONT FOR THURSDAY THROUGH FRIDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 453 PM MST SAT NOV 22 2014

STRONG AND GUSTY WESTERLY WINDS WILL CONTINUE TONIGHT WITH
THE PASSAGE OF A PACIFIC COLD FRONT. GUSTS TO 50 KT WILL
STILL BE POSSIBLE EARLY THIS EVENING...MAINLY INVOF THE
MOUNTAINS. GUSTS WILL DECREASE TO 30-40 KT LATER THIS EVENING
AND OVERNIGHT. MVFR CONDITIONS IN RAIN/SNOW SHOWERS WEST OF THE
LARAMIE RANGE WILL SPREAD EAST ONTO THE PLAINS TONIGHT...WITH
OCCASIONAL IFR POSSIBLE. PRECIPITATION WILL TAPER OFF WITH
IMPROVING CIGS/VSBYS SUNDAY MORNING.

&&

.FIRE WEATHER...
ISSUED AT 209 PM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG THROUGH EARLY NEXT WEEK...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED DUE TO COOL TEMPERATURES AND HIGH
RELATIVE HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...HIGH WIND WARNING UNTIL MIDNIGHT MST TONIGHT FOR WYZ101-103>107-
     110-115>118.

     WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ112-114.

NE...WIND ADVISORY FROM 9 AM TO 6 PM MST SUNDAY FOR NEZ002-003-
     019>021-054-055-095-096.

&&

$$

SHORT TERM...TJT
LONG TERM...GCC
AVIATION...MJ
FIRE WEATHER...TJT



000
FXUS63 KUNR 222329
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
429 PM MST SAT NOV 22 2014

.SHORT TERM...THIS EVENING THROUGH SUNDAY NIGHT
ISSUED AT 426 PM MST SAT NOV 22 2014

DEEPENING NW CONUS UPPER TROUGH WILL ADVECT THROUGH THE REGION
THROUGH SUNDAY...SUPPORTING A COLD FRONT INTO THE AREA...WITH
CHANCES FOR SNOW AND INCREASING WINDS. THERMAL RIDGE HAS SUPPORTED
A MILD DAY ACROSS THE AREA...ESP WHERE ENHANCED LOCAL MIXING HAS
OCCURRED. HOWEVER...INCREASING LSA WITH A LL COLD FRONT WILL
SUPPORT A WEAK FGEN BAND OF PRECIP ACROSS THE AREA TONIGHT.
SECONDARY COLD FRONT WITH STEEP LL LAPSE RATES AND CYCLONIC FLOW
ALOFT WILL THEN SUPPORT INCREASING CHANCES FOR DIURNALLY DRIVEN
SNOW SHOWERS SUNDAY...WITH FAVORABLE UPSLOPE FORCING OVER THE
NORTHERN HILLS. ACTIVE NW FLOW WILL SUSTAIN THROUGH SUNDAY
NIGHT...WITH ANOTHER IMPULSE EXPECTED TO INFLUENCE THE WESTERN FA
LATE SUNDAY.

TONIGHT...SPLITTING NW CONUS UPPER TROUGH WILL SUPPORT A WEAK HIGH
CENTERED FGEN RESPONSE OVER THE REGION WITH INCREASING MID LEVEL
MOISTURE. STEEP MID LEVEL LAPSE RATES COMBINED WITH SUFFICIENT MID
LEVEL MOISTURE AND INCREASING UVM SHOULD BE ENOUGH TO SUPPORT SCT
RAIN/SNOW SHOWERS OVER THE REGION...ESP NE WY WHERE BETTER FORCING
FOR ACCENT WILL BE IN PLACE. ANY PRECIP WILL MAINLY BE IN THE FORM OF
RAIN THIS EVENING...QUICKLY TRANSITIONING TO SNOW OVERNIGHT GIVEN
COOLING THERMAL FIELDS. ANY SNOW AMOUNTS WILL GENERALLY BE LESS THAN
ONE INCH. LL FLOW WILL VEER NW TONIGHT AND INCREASE AFTER MIDNIGHT.
INITIAL CAA PUSH AND PRESSURE RISES MAY SUPPORT A PERIOD OF NEAR ADV
WINDS AROUND KRAP AFTER MIDNIGHT. HOWEVER...WINDS SHOULD GENERALLY
REMAIN TAME UNTIL LATER SUNDAY MORNING.

SUNDAY...SECONDARY CAA PUSH AND INCREASING LL FLOW WILL SUPPORT A
WINDY DAY ACROSS THE REGION. MEAN BL FLOW PROGS SUPPORT SUSTAINED
WINDS OF 30-35 KNOTS ESP ACROSS FAR NW SD. BUFR PROGS INDICATE THE
POTENTIAL FOR WINDS OF 50 KNOTS TO MIX DOWN...ESP WITH THE SECONDARY
PRESSURE RISE SURGE EARLY SUNDAY AFTERNOON ACROSS THE FAR NW. IN
ADDITION...COLD POCKET ALOFT COMBINED WITH DIURNAL HEATING WILL
SUPPORT THE DEVELOPMENT OF SNOW SHOWERS...WITH LOCAL ENHANCED
DOWNWARD MOMENTUM TRANSPORT POSSIBLE IN THE VICINITY OF ANY SHOWER.
HAVE DECIDED TO ISSUE A WIND ADV FOR MUCH OF THE SD
PLAINS...RETAINING A HIGH WIND WATCH ACROSS THE FAR NW WHERE THE
BEST POTENTIAL FOR DOWNWARD MOMENTUM TRANSPORT OF 50 KNOT FLOW WILL
RESIDE. MEAN MODEL TRENDS HAVE SUPPORTED SLIGHTLY WEAKER WINDS
ACROSS THE AREA...BUT WOULD LIKE TO HAVE ANOTHER FORECAST RUN OR TWO
TO SEE IF THIS TREND SUSTAINS. THERE IS ALSO THE POTENTIAL FOR
LOCALIZED STRONG WINDS ALONG THE PLAINS OF THE EASTERN BLACK
HILLS...INCLUDING RAPID CITY...WITH NEAR HIGH WIND WARNING POSSIBLE.
HOWEVER...GIVEN THE LOW POTENTIAL/SHORT DURATION/AND LOCALIZED
NATURE...FEEL A WIND ADV IS MORE PRUDENT. THE OTHER HIGHLIGHT WILL
BE INCREASINGLY FAVORABLE CONDITIONS FOR UPSLOPE SNOWS ACROSS THE
NORTHERN BLACK HILLS...MAINLY FROM THE BEAR LODGE MOUNTAINS TO
CHEYENNE CROSSING. INCREASING FROUDE/MOISTURE/AND FLOW WITH COOLING
THERMAL FIELDS IN STEEP LL LAPSE RATES WILL SUPPORT A DECENT PERIOD
OF UPSLOPE FORCING...EXTENDING INTO THE DGZ. 1 TO 3 INCHES WITH
LOCALLY HIGHER AMOUNTS WILL BE POSSIBLE IN THIS AREA. SNOW WILL WIND
DOWN SUNDAY EVENING AS THE BL DRIES. HOWEVER...AS SECONDARY IMPULSE
WILL LEAD TO RENEWED CHANCES FOR SNOW...MAINLY NE WY LATE SUNDAY
NIGHT.

&&

.LONG TERM...MONDAY THROUGH SATURDAY
ISSUED AT 426 PM MST SAT NOV 22 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW ALOFT WILL
CONTINUE ACROSS THE NORTHERN HIGH PLAINS EARLY NEXT WEEK. SEVERAL
WEAK DISTURBANCES WITHIN NORTHWEST FLOW WILL SLIDE THROUGH...BRINGING
A GOOD DEAL OF CLOUDINESS AND CHANCES FOR SNOW SHOWERS AT TIMES
THROUGH WEDNESDAY. THE BEST CHANCES FOR SNOW WILL GENERALLY BE
ACROSS NORTHEAST WY AND THE NORTHERN BLACK HILLS AREA.

FOR THE HOLIDAY PERIOD...THE LATEST RUNS OF THE GFS...ECMWF...AND
CANADIAN HAVE ALL FLIPPED BACK TO A COLDER REGIME FOR LATE IN THE
WEEK AS A CANADIAN COLD FRONT IS PROGGED TO SLIDE SOUTH THROUGH THE
AREA LATE WEDNESDAY/WEDNESDAY NIGHT. WILL TREND COLDER AGAIN FOR
THANKSGIVING DAY AND THE REST OF THE EXTENDED...BUT UNCERTAINTY
STILL EXISTS WITH REGARD TO TEMPS. IT DOES CONTINUE TO LOOK MAINLY
DRY DURING THE PERIOD THOUGH.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING
ISSUED AT 426 PM MST SAT NOV 22 2014

A COLD FRONT WILL CROSS THE AREA TONIGHT...WITH GUSTY NORTHWEST
WINDS DEVELOPING BEHIND THE FRONT. A FEW RAIN SHOWERS ARE
EXPECTED THIS EVENING OVER MAINLY NORTHEAST WY AND FAR WESTERN
SD...CHANGING TO SNOW SHOWERS OVERNIGHT. SOME AREAS OF MVFR
CONDITIONS ARE EXPECTED...ESPECIALLY ACROSS FAR NORTHEAST WY AND
THE BLACK HILLS. STRONGER NORTHWEST WINDS WILL DEVELOP ACROSS THE
AREA SUNDAY MORNING.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY FROM 8 AM MST /9 AM CST/ TO 8 PM MST /9 PM CST/
     SUNDAY FOR SDZ014-025>027-031-032-041-043-044-046-047-049-
     072.

     HIGH WIND WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR
     SDZ001-002-012-013-073.

WY...NONE.
&&

$$

SHORT TERM...JC
LONG TERM...26
AVIATION...26





000
FXUS63 KUNR 222329
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
429 PM MST SAT NOV 22 2014

.SHORT TERM...THIS EVENING THROUGH SUNDAY NIGHT
ISSUED AT 426 PM MST SAT NOV 22 2014

DEEPENING NW CONUS UPPER TROUGH WILL ADVECT THROUGH THE REGION
THROUGH SUNDAY...SUPPORTING A COLD FRONT INTO THE AREA...WITH
CHANCES FOR SNOW AND INCREASING WINDS. THERMAL RIDGE HAS SUPPORTED
A MILD DAY ACROSS THE AREA...ESP WHERE ENHANCED LOCAL MIXING HAS
OCCURRED. HOWEVER...INCREASING LSA WITH A LL COLD FRONT WILL
SUPPORT A WEAK FGEN BAND OF PRECIP ACROSS THE AREA TONIGHT.
SECONDARY COLD FRONT WITH STEEP LL LAPSE RATES AND CYCLONIC FLOW
ALOFT WILL THEN SUPPORT INCREASING CHANCES FOR DIURNALLY DRIVEN
SNOW SHOWERS SUNDAY...WITH FAVORABLE UPSLOPE FORCING OVER THE
NORTHERN HILLS. ACTIVE NW FLOW WILL SUSTAIN THROUGH SUNDAY
NIGHT...WITH ANOTHER IMPULSE EXPECTED TO INFLUENCE THE WESTERN FA
LATE SUNDAY.

TONIGHT...SPLITTING NW CONUS UPPER TROUGH WILL SUPPORT A WEAK HIGH
CENTERED FGEN RESPONSE OVER THE REGION WITH INCREASING MID LEVEL
MOISTURE. STEEP MID LEVEL LAPSE RATES COMBINED WITH SUFFICIENT MID
LEVEL MOISTURE AND INCREASING UVM SHOULD BE ENOUGH TO SUPPORT SCT
RAIN/SNOW SHOWERS OVER THE REGION...ESP NE WY WHERE BETTER FORCING
FOR ACCENT WILL BE IN PLACE. ANY PRECIP WILL MAINLY BE IN THE FORM OF
RAIN THIS EVENING...QUICKLY TRANSITIONING TO SNOW OVERNIGHT GIVEN
COOLING THERMAL FIELDS. ANY SNOW AMOUNTS WILL GENERALLY BE LESS THAN
ONE INCH. LL FLOW WILL VEER NW TONIGHT AND INCREASE AFTER MIDNIGHT.
INITIAL CAA PUSH AND PRESSURE RISES MAY SUPPORT A PERIOD OF NEAR ADV
WINDS AROUND KRAP AFTER MIDNIGHT. HOWEVER...WINDS SHOULD GENERALLY
REMAIN TAME UNTIL LATER SUNDAY MORNING.

SUNDAY...SECONDARY CAA PUSH AND INCREASING LL FLOW WILL SUPPORT A
WINDY DAY ACROSS THE REGION. MEAN BL FLOW PROGS SUPPORT SUSTAINED
WINDS OF 30-35 KNOTS ESP ACROSS FAR NW SD. BUFR PROGS INDICATE THE
POTENTIAL FOR WINDS OF 50 KNOTS TO MIX DOWN...ESP WITH THE SECONDARY
PRESSURE RISE SURGE EARLY SUNDAY AFTERNOON ACROSS THE FAR NW. IN
ADDITION...COLD POCKET ALOFT COMBINED WITH DIURNAL HEATING WILL
SUPPORT THE DEVELOPMENT OF SNOW SHOWERS...WITH LOCAL ENHANCED
DOWNWARD MOMENTUM TRANSPORT POSSIBLE IN THE VICINITY OF ANY SHOWER.
HAVE DECIDED TO ISSUE A WIND ADV FOR MUCH OF THE SD
PLAINS...RETAINING A HIGH WIND WATCH ACROSS THE FAR NW WHERE THE
BEST POTENTIAL FOR DOWNWARD MOMENTUM TRANSPORT OF 50 KNOT FLOW WILL
RESIDE. MEAN MODEL TRENDS HAVE SUPPORTED SLIGHTLY WEAKER WINDS
ACROSS THE AREA...BUT WOULD LIKE TO HAVE ANOTHER FORECAST RUN OR TWO
TO SEE IF THIS TREND SUSTAINS. THERE IS ALSO THE POTENTIAL FOR
LOCALIZED STRONG WINDS ALONG THE PLAINS OF THE EASTERN BLACK
HILLS...INCLUDING RAPID CITY...WITH NEAR HIGH WIND WARNING POSSIBLE.
HOWEVER...GIVEN THE LOW POTENTIAL/SHORT DURATION/AND LOCALIZED
NATURE...FEEL A WIND ADV IS MORE PRUDENT. THE OTHER HIGHLIGHT WILL
BE INCREASINGLY FAVORABLE CONDITIONS FOR UPSLOPE SNOWS ACROSS THE
NORTHERN BLACK HILLS...MAINLY FROM THE BEAR LODGE MOUNTAINS TO
CHEYENNE CROSSING. INCREASING FROUDE/MOISTURE/AND FLOW WITH COOLING
THERMAL FIELDS IN STEEP LL LAPSE RATES WILL SUPPORT A DECENT PERIOD
OF UPSLOPE FORCING...EXTENDING INTO THE DGZ. 1 TO 3 INCHES WITH
LOCALLY HIGHER AMOUNTS WILL BE POSSIBLE IN THIS AREA. SNOW WILL WIND
DOWN SUNDAY EVENING AS THE BL DRIES. HOWEVER...AS SECONDARY IMPULSE
WILL LEAD TO RENEWED CHANCES FOR SNOW...MAINLY NE WY LATE SUNDAY
NIGHT.

&&

.LONG TERM...MONDAY THROUGH SATURDAY
ISSUED AT 426 PM MST SAT NOV 22 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW ALOFT WILL
CONTINUE ACROSS THE NORTHERN HIGH PLAINS EARLY NEXT WEEK. SEVERAL
WEAK DISTURBANCES WITHIN NORTHWEST FLOW WILL SLIDE THROUGH...BRINGING
A GOOD DEAL OF CLOUDINESS AND CHANCES FOR SNOW SHOWERS AT TIMES
THROUGH WEDNESDAY. THE BEST CHANCES FOR SNOW WILL GENERALLY BE
ACROSS NORTHEAST WY AND THE NORTHERN BLACK HILLS AREA.

FOR THE HOLIDAY PERIOD...THE LATEST RUNS OF THE GFS...ECMWF...AND
CANADIAN HAVE ALL FLIPPED BACK TO A COLDER REGIME FOR LATE IN THE
WEEK AS A CANADIAN COLD FRONT IS PROGGED TO SLIDE SOUTH THROUGH THE
AREA LATE WEDNESDAY/WEDNESDAY NIGHT. WILL TREND COLDER AGAIN FOR
THANKSGIVING DAY AND THE REST OF THE EXTENDED...BUT UNCERTAINTY
STILL EXISTS WITH REGARD TO TEMPS. IT DOES CONTINUE TO LOOK MAINLY
DRY DURING THE PERIOD THOUGH.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING
ISSUED AT 426 PM MST SAT NOV 22 2014

A COLD FRONT WILL CROSS THE AREA TONIGHT...WITH GUSTY NORTHWEST
WINDS DEVELOPING BEHIND THE FRONT. A FEW RAIN SHOWERS ARE
EXPECTED THIS EVENING OVER MAINLY NORTHEAST WY AND FAR WESTERN
SD...CHANGING TO SNOW SHOWERS OVERNIGHT. SOME AREAS OF MVFR
CONDITIONS ARE EXPECTED...ESPECIALLY ACROSS FAR NORTHEAST WY AND
THE BLACK HILLS. STRONGER NORTHWEST WINDS WILL DEVELOP ACROSS THE
AREA SUNDAY MORNING.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY FROM 8 AM MST /9 AM CST/ TO 8 PM MST /9 PM CST/
     SUNDAY FOR SDZ014-025>027-031-032-041-043-044-046-047-049-
     072.

     HIGH WIND WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR
     SDZ001-002-012-013-073.

WY...NONE.
&&

$$

SHORT TERM...JC
LONG TERM...26
AVIATION...26




000
FXUS65 KCYS 222206
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
306 PM MST SAT NOV 22 2014

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM MST SAT NOV 22 2014

PRIMARY CONCERNS THROUGH THIS WEEKEND WILL BE WINDS AND MOUNTAIN
SNOWFALL. MOST OF THE AREA WITHIN THE HIGH WIND WARNING HAS
VERIFIED THIS AFTERNOON WITH GUSTS AS HIGH AS 76 MPH REPORTED
ALONG I25 AND I80. ELSEWHERE...WINDS HAVE STRUGGLED ACROSS
LOCATIONS SUCH AS THE LARAMIE VALLEY AND THE HIGH PLAINS
IMMEDIATELY EAST OF THE LARAMIE RANGE. BELIEVE THIS IS DUE TO A
COMBINATION OF CLOUDY SKIES AND AN AREA OF POSITIVE OMEGA EAST OF
THE MOUNTAINS. WILL KEEP THE HIGH WIND WARNING OUT FOR THESE
AREAS...BUT THERE IS ONLY A SMALL WINDOW TO SEE GUSTS AROUND 55
MPH SINCE DOWNSLOPE AND SUBSIDENCE WILL BEGIN TO DIMINISH BY LATE
THIS EVENING. ENDED THE HIGH WIND WARNING AT MIDNIGHT TONIGHT
SINCE THE FRONT AND IS TRENDING A BIT FASTER AND SHOULD BE NEAR
THE COLORADO BORDER A FEW HOURS BEFORE MIDNIGHT. AFTER THE FRONT
AND ASSOCIATED TROUGH AXIS ALOFT MOVES THROUGH...WINDS WILL SHIFT
INTO THE NORTHWEST WHICH WILL END THE HIGH WIND EVENT BRIEFLY FOR
THE WIND PRONE AREAS AS WELL. HOWEVER...HIGH WINDS WILL LIKELY
RETURN BY LATE MONDAY NIGHT ACROSS MOST OF SOUTHEAST WYOMING.

SNOW WILL BE ANOTHER CONCERN...PRIMARILY ACROSS THE MOUNTAINS OF
SOUTHEAST WYOMING AND PERHAPS EVEN SOME OF THE HIGH VALLEYS. SNOW
IS DEVELOPING ACROSS THE MOUNTAINS EARLY THIS AFTERNOON WITH SOME
RAIN/SNOW MIX DOWN TO THE VALLEY FLOORS. ANY RAINFALL WILL QUICKLY
CHANGE TO SNOW LATE THIS AFTERNOON AS MUCH COLDER AIR MOVES INTO
THE AREA. THE HEAVIEST SNOW WILL BE TONIGHT...BUT ANOTHER
DISTURBANCE ALOFT WILL PUSH ACROSS THE AREA ON SUNDAY AS WELL
RESULTING IN SOME ENHANCEMENT OF SNOWFALL RATES. HIGH CONFIDENCE
THAT THE MOUNTAINS WILL DO WELL WITH THIS EVENT...SO KEPT THE
WINTER STORM WARNING GOING THROUGH MONDAY FOR 1 TO 2 FEET OF SNOW.
EXPECT THE PRECIPITATION TO BE ENHANCED FURTHER ON THE WEST TO
NORTHWEST FACING SLOPES AND RIDGES DUE TO UPSLOPE FLOW. FOR THE
VALLEYS AND HIGH PLAINS...EXPECT PERHAPS 1 TO 2 INCHES ALONG I80
WEST OF THE LARAMIE RANGE AND FURTHER NORTH ALONG I80 AROUND
DOUGLAS. THE CHEYENNE RIDGE FROM CHEYENNE TO SIDNEY INCLUDING MOST
OF THE NEBRASKA PANHANDLE WILL BE LUCKY TO SEE A DUSTING OF SNOW
DUE TO THE LARGE LLVL DOWNSLOPE COMPONENT TO THE WINDS. THE BEST
CHANCE TO SEE SOME SNOW WILL BE NEAR THE FRONTAL PASSAGE DUE TO
BRIEF FRONTOGENESIS AND LLVL DYNAMIC LIFT. THERE IS SOME CONCERN
THAT THE ADJACENT VALLEYS ACROSS SOUTHERN CARBON COUNTY WILL SEE
SOME MODERATE SNOWFALL RATES AS THE WINDS SHIFT INTO THE
NORTHWEST. WILL CONTINUE TO KEEP AN EYE ON THIS THROUGH SUNDAY AS
THE NEXT DISTURBANCE MOVES ACROSS THE AREA. FOR NOW...KEPT 1 TO 3
INCHES OF SNOW IN THESE LOCATIONS WITH 5 INCHES POSSIBLE LOCALLY.

FOR MONDAY...ANOTHER DISTURBANCE ALOFT WILL MOVE ACROSS THE
AREA...RESULTING IN ENHANCED SNOWFALL RATES ACROSS THE MOUNTAINS
AFTER A BRIEF LULL SUNDAY NIGHT. THIS MAY BE THE BEST CHANCE FOR
THE HIGH PLAINS TO RECEIVE SOME WIDESPREAD LIGHT SNOW
ACCUMULATIONS AS WINDS SHIFT INTO THE NORTH.


.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 300 PM MST SAT NOV 22 2014

STRONG WINDS CONTINUE THROUGH AT LEAST WEDNESDAY. GFS SHOWING A
1041MB SURFACE HIGH OVER WESTERN COLORADO TUESDAY MORNING WITH
A ROUGHLY 10-12MB SURFACE GRADIENT BETWEEN CASPER AND CRAIG.
700MB WINDS FROM THE NORTHWEST AT 50-60KTS WITH A 700MB HEIGHT
GRADIENT AROUND 70 TO 80 MARS BETWEEN CRAIG AND CASPER. ALMOST A
SURE THING FOR WIND WARNING CRITERIA AT LEAST FOR THE WIND PRONE
AREAS AND HAVE BUMPED UP GUIDANCE AT THESE LOCATIONS TO REFLECT
CONFIDENCE IN HIGH WINDS.

WINDS LOOK TO FINALLY EASE SOME THURSDAY AS WE SEE A FRONT DIVE
SOUTHWEST OUT OF THE DAKOTAS AND LAY UP AGAINST THE LARAMIE RANGE.
ECMWF A LITTLE FURTHER NORTHEAST WITH THIS FRONT OVER THE MORE
AGGRESSIVE GFS...FINALLY PUSHING THE BOUNDARY INTO THE LARAMIE
RANGE THURSDAY EVENING. DID GO AHEAD AND LOWER TEMPERATURES SOME
OVER THE NORTHERN PANHANDLE AND OUR EASTERN ZONES TO REFLECT THE
MUCH COLDER AIR BEHIND THE FRONT FOR THURSDAY THROUGH FRIDAY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1031 AM MST SAT NOV 22 2014

VERY WINDY CONDITIONS ACROSS SOUTHEAST WYOMING WITH GUSTY WINDS IN
THE PANHANDLE. LOOK FOR DETERIORATING CONDITIONS OUT NEAR KRWL
LATER THIS AFTERNOON AS RAIN SHOWERS TURN OVER TO SNOW. THESE
LOWERING CONDITIONS COULD IMPACT THE PANHANDLE AIRPORTS TONIGHT AS
LATEST GUIDANCE DOES SHOW SHOWERS DEVELOPING OUT THERE OVERNIGHT.


&&

.FIRE WEATHER...
ISSUED AT 209 PM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG THROUGH EARLY NEXT WEEK...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED DUE TO COOL TEMPERATURES AND HIGH
RELATIVE HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...HIGH WIND WARNING UNTIL MIDNIGHT MST TONIGHT FOR WYZ101-103>107-
     110-115>118.

     WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ112-114.

NE...WIND ADVISORY FROM 9 AM TO 6 PM MST SUNDAY FOR NEZ002-003-
     019>021-054-055-095-096.

&&

$$

SHORT TERM...TJT
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...TJT



000
FXUS65 KCYS 222206
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
306 PM MST SAT NOV 22 2014

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 300 PM MST SAT NOV 22 2014

PRIMARY CONCERNS THROUGH THIS WEEKEND WILL BE WINDS AND MOUNTAIN
SNOWFALL. MOST OF THE AREA WITHIN THE HIGH WIND WARNING HAS
VERIFIED THIS AFTERNOON WITH GUSTS AS HIGH AS 76 MPH REPORTED
ALONG I25 AND I80. ELSEWHERE...WINDS HAVE STRUGGLED ACROSS
LOCATIONS SUCH AS THE LARAMIE VALLEY AND THE HIGH PLAINS
IMMEDIATELY EAST OF THE LARAMIE RANGE. BELIEVE THIS IS DUE TO A
COMBINATION OF CLOUDY SKIES AND AN AREA OF POSITIVE OMEGA EAST OF
THE MOUNTAINS. WILL KEEP THE HIGH WIND WARNING OUT FOR THESE
AREAS...BUT THERE IS ONLY A SMALL WINDOW TO SEE GUSTS AROUND 55
MPH SINCE DOWNSLOPE AND SUBSIDENCE WILL BEGIN TO DIMINISH BY LATE
THIS EVENING. ENDED THE HIGH WIND WARNING AT MIDNIGHT TONIGHT
SINCE THE FRONT AND IS TRENDING A BIT FASTER AND SHOULD BE NEAR
THE COLORADO BORDER A FEW HOURS BEFORE MIDNIGHT. AFTER THE FRONT
AND ASSOCIATED TROUGH AXIS ALOFT MOVES THROUGH...WINDS WILL SHIFT
INTO THE NORTHWEST WHICH WILL END THE HIGH WIND EVENT BRIEFLY FOR
THE WIND PRONE AREAS AS WELL. HOWEVER...HIGH WINDS WILL LIKELY
RETURN BY LATE MONDAY NIGHT ACROSS MOST OF SOUTHEAST WYOMING.

SNOW WILL BE ANOTHER CONCERN...PRIMARILY ACROSS THE MOUNTAINS OF
SOUTHEAST WYOMING AND PERHAPS EVEN SOME OF THE HIGH VALLEYS. SNOW
IS DEVELOPING ACROSS THE MOUNTAINS EARLY THIS AFTERNOON WITH SOME
RAIN/SNOW MIX DOWN TO THE VALLEY FLOORS. ANY RAINFALL WILL QUICKLY
CHANGE TO SNOW LATE THIS AFTERNOON AS MUCH COLDER AIR MOVES INTO
THE AREA. THE HEAVIEST SNOW WILL BE TONIGHT...BUT ANOTHER
DISTURBANCE ALOFT WILL PUSH ACROSS THE AREA ON SUNDAY AS WELL
RESULTING IN SOME ENHANCEMENT OF SNOWFALL RATES. HIGH CONFIDENCE
THAT THE MOUNTAINS WILL DO WELL WITH THIS EVENT...SO KEPT THE
WINTER STORM WARNING GOING THROUGH MONDAY FOR 1 TO 2 FEET OF SNOW.
EXPECT THE PRECIPITATION TO BE ENHANCED FURTHER ON THE WEST TO
NORTHWEST FACING SLOPES AND RIDGES DUE TO UPSLOPE FLOW. FOR THE
VALLEYS AND HIGH PLAINS...EXPECT PERHAPS 1 TO 2 INCHES ALONG I80
WEST OF THE LARAMIE RANGE AND FURTHER NORTH ALONG I80 AROUND
DOUGLAS. THE CHEYENNE RIDGE FROM CHEYENNE TO SIDNEY INCLUDING MOST
OF THE NEBRASKA PANHANDLE WILL BE LUCKY TO SEE A DUSTING OF SNOW
DUE TO THE LARGE LLVL DOWNSLOPE COMPONENT TO THE WINDS. THE BEST
CHANCE TO SEE SOME SNOW WILL BE NEAR THE FRONTAL PASSAGE DUE TO
BRIEF FRONTOGENESIS AND LLVL DYNAMIC LIFT. THERE IS SOME CONCERN
THAT THE ADJACENT VALLEYS ACROSS SOUTHERN CARBON COUNTY WILL SEE
SOME MODERATE SNOWFALL RATES AS THE WINDS SHIFT INTO THE
NORTHWEST. WILL CONTINUE TO KEEP AN EYE ON THIS THROUGH SUNDAY AS
THE NEXT DISTURBANCE MOVES ACROSS THE AREA. FOR NOW...KEPT 1 TO 3
INCHES OF SNOW IN THESE LOCATIONS WITH 5 INCHES POSSIBLE LOCALLY.

FOR MONDAY...ANOTHER DISTURBANCE ALOFT WILL MOVE ACROSS THE
AREA...RESULTING IN ENHANCED SNOWFALL RATES ACROSS THE MOUNTAINS
AFTER A BRIEF LULL SUNDAY NIGHT. THIS MAY BE THE BEST CHANCE FOR
THE HIGH PLAINS TO RECEIVE SOME WIDESPREAD LIGHT SNOW
ACCUMULATIONS AS WINDS SHIFT INTO THE NORTH.


.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 300 PM MST SAT NOV 22 2014

STRONG WINDS CONTINUE THROUGH AT LEAST WEDNESDAY. GFS SHOWING A
1041MB SURFACE HIGH OVER WESTERN COLORADO TUESDAY MORNING WITH
A ROUGHLY 10-12MB SURFACE GRADIENT BETWEEN CASPER AND CRAIG.
700MB WINDS FROM THE NORTHWEST AT 50-60KTS WITH A 700MB HEIGHT
GRADIENT AROUND 70 TO 80 MARS BETWEEN CRAIG AND CASPER. ALMOST A
SURE THING FOR WIND WARNING CRITERIA AT LEAST FOR THE WIND PRONE
AREAS AND HAVE BUMPED UP GUIDANCE AT THESE LOCATIONS TO REFLECT
CONFIDENCE IN HIGH WINDS.

WINDS LOOK TO FINALLY EASE SOME THURSDAY AS WE SEE A FRONT DIVE
SOUTHWEST OUT OF THE DAKOTAS AND LAY UP AGAINST THE LARAMIE RANGE.
ECMWF A LITTLE FURTHER NORTHEAST WITH THIS FRONT OVER THE MORE
AGGRESSIVE GFS...FINALLY PUSHING THE BOUNDARY INTO THE LARAMIE
RANGE THURSDAY EVENING. DID GO AHEAD AND LOWER TEMPERATURES SOME
OVER THE NORTHERN PANHANDLE AND OUR EASTERN ZONES TO REFLECT THE
MUCH COLDER AIR BEHIND THE FRONT FOR THURSDAY THROUGH FRIDAY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1031 AM MST SAT NOV 22 2014

VERY WINDY CONDITIONS ACROSS SOUTHEAST WYOMING WITH GUSTY WINDS IN
THE PANHANDLE. LOOK FOR DETERIORATING CONDITIONS OUT NEAR KRWL
LATER THIS AFTERNOON AS RAIN SHOWERS TURN OVER TO SNOW. THESE
LOWERING CONDITIONS COULD IMPACT THE PANHANDLE AIRPORTS TONIGHT AS
LATEST GUIDANCE DOES SHOW SHOWERS DEVELOPING OUT THERE OVERNIGHT.


&&

.FIRE WEATHER...
ISSUED AT 209 PM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG THROUGH EARLY NEXT WEEK...NO FIRE
WEATHER CONCERNS ARE ANTICIPATED DUE TO COOL TEMPERATURES AND HIGH
RELATIVE HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...HIGH WIND WARNING UNTIL MIDNIGHT MST TONIGHT FOR WYZ101-103>107-
     110-115>118.

     WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ112-114.

NE...WIND ADVISORY FROM 9 AM TO 6 PM MST SUNDAY FOR NEZ002-003-
     019>021-054-055-095-096.

&&

$$

SHORT TERM...TJT
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...TJT




000
FXUS65 KCYS 222114
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
215 PM MST SAT NOV 22 2014

.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 342 AM MST SAT NOV 22 2014

TODAY...INHERITED WIND AND SNOW HIGHLITES LOOK ON TRACK. FOR
WIND...ARLINGTON ALREADY SEEING SUSTAINED 45 MPH WITH GUSTS IN THE
MID 50S. WINDS EXPECTED TO CONTINUE TO RAMP UP AS 850/700 MB CRAIG
TO CASPER HEIGHT GRADIENTS RISE TO NEAR 70 METERS BY LATE AFTERNOON.
BASED ON LOW AND MID LEVEL HEIGHT GRADIENTS...INHERITED HIGH WIND
WARNING ON TRACK...AND WILL UPGRADE THE HIGH WIND WATCH TO A WARNING
FOR LATE MORNING AND LATER TODAY FOR CHEYENNE...PLATTE AND CONVERSE
COUNTIES AS AGREE WITH DAY SHIFT REASONING FROM YESTERDAY. PROGGED
SURFACE THROUGH 700 MB GRADIENTS LOOK FAVORABLE. OROGRAPHIC SNOWS
EXPECTED TO CRANK UP LATE THIS AFTERNOON OVER THE SNOWY AND SIERRA
MADRE RANGES AS A PACIFIC COLD FRONT ENTERS THE REGION. FORECAST QPF
AND OROGRAPHICS SUGGEST AN UPGRADE TO A WINTER STORM WARNING THERE.

TONIGHT...STRONG BORA WINDS CONTINUE IN THE POST COLD FRONTAL
AIRMASS AND THUS THE CONTINUATION OF THE HIGH WIND WARNING. HEIGHT
GRADIENTS DECREASE THUS SLOWLY DECREASING WINDS. MODERATE TO HEAVY
SNOW WILL CONTINUE OVER THE SNOWY AND SIERRA MADRE RANGES IN MOIST
OROGRAPHIC FLOW.

SUNDAY...BLUSTERY AND WINDY DAY IN THE WAKE OF THE COLD FRONT WITH
OROGRAPHIC SNOWS IN EARNEST CONTINUING OVER THE SOUTHWEST MOUNTAINS.

SUNDAY NIGHT...CONTINUED BREEZY TO WINDY PER PROGGED SURFACE THROUGH
700 MB GRADIENTS...THOUGH NOT AS WINDY AS SATURDAY NIGHT. COLD AND
BLUSTERY WITH OROGRAPHIC SNOWS CONTINUING IN MOIST FLOW OVER THE
SNOWY AND SIERRA MADRE RANGES.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 342 AM MST SAT NOV 22 2014

ONGOING SNOW EVENT OVR THE SNOWY AND SIERRA MADRE RANGES WILL KICK
OFF THE PERIOD AS TRAILING SHORTWAVE TROUGH IN NORTHWEST FLOW CLIPS
THE AREA. MOUNTAINS LOCATIONS WILL SEE AN ADDITIONAL 3 TO 6 INCHES
ON MONDAY. THESE RATES WILL CONTINUE TO WARRANT THE AFOREMENTIONED
WINTER STORM WARNING OVR THE MOUNTAINS. POST-FRONTAL NORTHWEST FLOW
WILL NOT BE ALL THAT FAVORABLE FOR PRECIP OUTSIDE OF OROGRAPHIC
AREAS...HOWEVER MAY SEE NW/SE ORIENTED SNOW BANDS SET UP...
ESPECIALLY DURING THE AFTERNOON HOURS. POST FRONTAL LLVL CAA WILL
YIELD HIGHS MONDAY ONLY IN THE 20S WEST OF THE LARAMIE RANGE...WITH
30S ON THE ERN PLAINS. IT WILL FEEL MUCH COLDER HOWEVER...WITH
NORTHWEST WINDS GUSTING TO 35-45 MPH AT TIMES. DEPENDING UPON THE
AMOUNT OF CLEARING/MIXING...AREAS IN THE PANHANDLE MAY NEED A WIND
ADVISORY IN TIME.

NW FLOW WILL CONTINUE ON TUESDAY. OROGRAPHICALLY FAVORED AREAS WILL
STILL SEE LT SNOW...HOWEVER RATES SHOULD NO LONGER NECESSITATE A
WINTER HIGHLIGHT. ANY SNOW CHANCES WILL AGAIN STRUGGLE TO PULL AWAY
FROM THE MTNS...ESPECIALLY DURING THE DAYTIME HOURS. THE ECMWF DOES
HINT THAT SNOW CHANCES WILL SPILL OUT ONTO THE PLAINS TUESDAY NIGHT.
THE GFS IS LESS AGGRESSIVE WITH THIS IDEA HOWEVER...CONFINING
CHANCES TO THE MOUNTAINS TUESDAY NIGHT. ANOTHER DAY OF BREEZY WEST
WINDS ACROSS THE CWFA TUESDAY WITH GUSTS AGAIN 30-40 MPH.

MEDIUM RANGE MODELS CONTINUE TO STRUGGLE WED-SAT...WITH THE MILLION
DOLLAR QUESTION CENTERING AROUND THE POSSIBILITY OF AN ARCTIC
BOUNDARY BCMNG STATIONARY WED NIGHT AND THU. MODELS ARE NOTORIOUS
FOR STRUGGLING IN THE DEPTH OF COLD AIR MASS THIS FAR OUT. THE 00Z
ECMWF IS MUCH MORE AMPLIFIED WITH A BUILDING RIDGE ALONG THE WEST
COAST...WHILE THE GFS IS SIGNIFICANTLY FLATTER. SO DESPITE SOME
SOLUTION CONGRUENCY IN YESTERDAYS 12Z MODEL SUITES...DIFFERENCES
REAR THEIR UGLY HEAD ONCE AGAIN IN 00Z DATA. FOR NOW...HAVE KEPT
THINGS RELATIVELY DRY AND MILD...FAVORING THE MORE CONSISTENT ECMWF.
HOWEVER...IF TRENDS TURN TOWARDS THE GFS COULD SEE A PERIOD OF SNOW
WED NT/THU ALONG WITH A COOLER THANKSGIVING DAY. STAY TUNED.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1031 AM MST SAT NOV 22 2014

VERY WINDY CONDITIONS ACROSS SOUTHEAST WYOMING WITH GUSTY WINDS IN
THE PANHANDLE. LOOK FOR DETERIORORATING CONDITIONS OUT NEAR KRWL
LATER THIS AFTERNOON AS RAIN SHOWERS TURN OVER TO SNOW. THESE
LOWERING CONDITIONS COULD IMPACT THE PANHANDLE AIRPORTS TONIGHT AS
LATEST GUIDANCE DOES SHOW SHOWERS DEVELOPING OUT THERE OVERNIGHT.

&&

.FIRE WEATHER...
ISSUED AT 342 AM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG TODAY AND TONIGHT...MINIMAL FIRE
WEATHER CONCERNS DUE TO COOL TEMPERATURES AND HIGHER HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO 5 PM MST MONDAY
     FOR WYZ112-114.

     HIGH WIND WARNING UNTIL 5 AM MST SUNDAY FOR WYZ101-103>106-110-
     116-117.

     HIGH WIND WARNING UNTIL 5 AM MST SUNDAY FOR WYZ107-115-118.

NE...NONE.
&&

$$

SHORT TERM...RUBIN
LONG TERM...CAH
AVIATION...GCC
FIRE WEATHER...RUBIN



000
FXUS65 KCYS 222114
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
215 PM MST SAT NOV 22 2014

.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 342 AM MST SAT NOV 22 2014

TODAY...INHERITED WIND AND SNOW HIGHLITES LOOK ON TRACK. FOR
WIND...ARLINGTON ALREADY SEEING SUSTAINED 45 MPH WITH GUSTS IN THE
MID 50S. WINDS EXPECTED TO CONTINUE TO RAMP UP AS 850/700 MB CRAIG
TO CASPER HEIGHT GRADIENTS RISE TO NEAR 70 METERS BY LATE AFTERNOON.
BASED ON LOW AND MID LEVEL HEIGHT GRADIENTS...INHERITED HIGH WIND
WARNING ON TRACK...AND WILL UPGRADE THE HIGH WIND WATCH TO A WARNING
FOR LATE MORNING AND LATER TODAY FOR CHEYENNE...PLATTE AND CONVERSE
COUNTIES AS AGREE WITH DAY SHIFT REASONING FROM YESTERDAY. PROGGED
SURFACE THROUGH 700 MB GRADIENTS LOOK FAVORABLE. OROGRAPHIC SNOWS
EXPECTED TO CRANK UP LATE THIS AFTERNOON OVER THE SNOWY AND SIERRA
MADRE RANGES AS A PACIFIC COLD FRONT ENTERS THE REGION. FORECAST QPF
AND OROGRAPHICS SUGGEST AN UPGRADE TO A WINTER STORM WARNING THERE.

TONIGHT...STRONG BORA WINDS CONTINUE IN THE POST COLD FRONTAL
AIRMASS AND THUS THE CONTINUATION OF THE HIGH WIND WARNING. HEIGHT
GRADIENTS DECREASE THUS SLOWLY DECREASING WINDS. MODERATE TO HEAVY
SNOW WILL CONTINUE OVER THE SNOWY AND SIERRA MADRE RANGES IN MOIST
OROGRAPHIC FLOW.

SUNDAY...BLUSTERY AND WINDY DAY IN THE WAKE OF THE COLD FRONT WITH
OROGRAPHIC SNOWS IN EARNEST CONTINUING OVER THE SOUTHWEST MOUNTAINS.

SUNDAY NIGHT...CONTINUED BREEZY TO WINDY PER PROGGED SURFACE THROUGH
700 MB GRADIENTS...THOUGH NOT AS WINDY AS SATURDAY NIGHT. COLD AND
BLUSTERY WITH OROGRAPHIC SNOWS CONTINUING IN MOIST FLOW OVER THE
SNOWY AND SIERRA MADRE RANGES.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 342 AM MST SAT NOV 22 2014

ONGOING SNOW EVENT OVR THE SNOWY AND SIERRA MADRE RANGES WILL KICK
OFF THE PERIOD AS TRAILING SHORTWAVE TROUGH IN NORTHWEST FLOW CLIPS
THE AREA. MOUNTAINS LOCATIONS WILL SEE AN ADDITIONAL 3 TO 6 INCHES
ON MONDAY. THESE RATES WILL CONTINUE TO WARRANT THE AFOREMENTIONED
WINTER STORM WARNING OVR THE MOUNTAINS. POST-FRONTAL NORTHWEST FLOW
WILL NOT BE ALL THAT FAVORABLE FOR PRECIP OUTSIDE OF OROGRAPHIC
AREAS...HOWEVER MAY SEE NW/SE ORIENTED SNOW BANDS SET UP...
ESPECIALLY DURING THE AFTERNOON HOURS. POST FRONTAL LLVL CAA WILL
YIELD HIGHS MONDAY ONLY IN THE 20S WEST OF THE LARAMIE RANGE...WITH
30S ON THE ERN PLAINS. IT WILL FEEL MUCH COLDER HOWEVER...WITH
NORTHWEST WINDS GUSTING TO 35-45 MPH AT TIMES. DEPENDING UPON THE
AMOUNT OF CLEARING/MIXING...AREAS IN THE PANHANDLE MAY NEED A WIND
ADVISORY IN TIME.

NW FLOW WILL CONTINUE ON TUESDAY. OROGRAPHICALLY FAVORED AREAS WILL
STILL SEE LT SNOW...HOWEVER RATES SHOULD NO LONGER NECESSITATE A
WINTER HIGHLIGHT. ANY SNOW CHANCES WILL AGAIN STRUGGLE TO PULL AWAY
FROM THE MTNS...ESPECIALLY DURING THE DAYTIME HOURS. THE ECMWF DOES
HINT THAT SNOW CHANCES WILL SPILL OUT ONTO THE PLAINS TUESDAY NIGHT.
THE GFS IS LESS AGGRESSIVE WITH THIS IDEA HOWEVER...CONFINING
CHANCES TO THE MOUNTAINS TUESDAY NIGHT. ANOTHER DAY OF BREEZY WEST
WINDS ACROSS THE CWFA TUESDAY WITH GUSTS AGAIN 30-40 MPH.

MEDIUM RANGE MODELS CONTINUE TO STRUGGLE WED-SAT...WITH THE MILLION
DOLLAR QUESTION CENTERING AROUND THE POSSIBILITY OF AN ARCTIC
BOUNDARY BCMNG STATIONARY WED NIGHT AND THU. MODELS ARE NOTORIOUS
FOR STRUGGLING IN THE DEPTH OF COLD AIR MASS THIS FAR OUT. THE 00Z
ECMWF IS MUCH MORE AMPLIFIED WITH A BUILDING RIDGE ALONG THE WEST
COAST...WHILE THE GFS IS SIGNIFICANTLY FLATTER. SO DESPITE SOME
SOLUTION CONGRUENCY IN YESTERDAYS 12Z MODEL SUITES...DIFFERENCES
REAR THEIR UGLY HEAD ONCE AGAIN IN 00Z DATA. FOR NOW...HAVE KEPT
THINGS RELATIVELY DRY AND MILD...FAVORING THE MORE CONSISTENT ECMWF.
HOWEVER...IF TRENDS TURN TOWARDS THE GFS COULD SEE A PERIOD OF SNOW
WED NT/THU ALONG WITH A COOLER THANKSGIVING DAY. STAY TUNED.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1031 AM MST SAT NOV 22 2014

VERY WINDY CONDITIONS ACROSS SOUTHEAST WYOMING WITH GUSTY WINDS IN
THE PANHANDLE. LOOK FOR DETERIORORATING CONDITIONS OUT NEAR KRWL
LATER THIS AFTERNOON AS RAIN SHOWERS TURN OVER TO SNOW. THESE
LOWERING CONDITIONS COULD IMPACT THE PANHANDLE AIRPORTS TONIGHT AS
LATEST GUIDANCE DOES SHOW SHOWERS DEVELOPING OUT THERE OVERNIGHT.

&&

.FIRE WEATHER...
ISSUED AT 342 AM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG TODAY AND TONIGHT...MINIMAL FIRE
WEATHER CONCERNS DUE TO COOL TEMPERATURES AND HIGHER HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO 5 PM MST MONDAY
     FOR WYZ112-114.

     HIGH WIND WARNING UNTIL 5 AM MST SUNDAY FOR WYZ101-103>106-110-
     116-117.

     HIGH WIND WARNING UNTIL 5 AM MST SUNDAY FOR WYZ107-115-118.

NE...NONE.
&&

$$

SHORT TERM...RUBIN
LONG TERM...CAH
AVIATION...GCC
FIRE WEATHER...RUBIN



000
FXUS65 KCYS 222114
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
215 PM MST SAT NOV 22 2014

.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 342 AM MST SAT NOV 22 2014

TODAY...INHERITED WIND AND SNOW HIGHLITES LOOK ON TRACK. FOR
WIND...ARLINGTON ALREADY SEEING SUSTAINED 45 MPH WITH GUSTS IN THE
MID 50S. WINDS EXPECTED TO CONTINUE TO RAMP UP AS 850/700 MB CRAIG
TO CASPER HEIGHT GRADIENTS RISE TO NEAR 70 METERS BY LATE AFTERNOON.
BASED ON LOW AND MID LEVEL HEIGHT GRADIENTS...INHERITED HIGH WIND
WARNING ON TRACK...AND WILL UPGRADE THE HIGH WIND WATCH TO A WARNING
FOR LATE MORNING AND LATER TODAY FOR CHEYENNE...PLATTE AND CONVERSE
COUNTIES AS AGREE WITH DAY SHIFT REASONING FROM YESTERDAY. PROGGED
SURFACE THROUGH 700 MB GRADIENTS LOOK FAVORABLE. OROGRAPHIC SNOWS
EXPECTED TO CRANK UP LATE THIS AFTERNOON OVER THE SNOWY AND SIERRA
MADRE RANGES AS A PACIFIC COLD FRONT ENTERS THE REGION. FORECAST QPF
AND OROGRAPHICS SUGGEST AN UPGRADE TO A WINTER STORM WARNING THERE.

TONIGHT...STRONG BORA WINDS CONTINUE IN THE POST COLD FRONTAL
AIRMASS AND THUS THE CONTINUATION OF THE HIGH WIND WARNING. HEIGHT
GRADIENTS DECREASE THUS SLOWLY DECREASING WINDS. MODERATE TO HEAVY
SNOW WILL CONTINUE OVER THE SNOWY AND SIERRA MADRE RANGES IN MOIST
OROGRAPHIC FLOW.

SUNDAY...BLUSTERY AND WINDY DAY IN THE WAKE OF THE COLD FRONT WITH
OROGRAPHIC SNOWS IN EARNEST CONTINUING OVER THE SOUTHWEST MOUNTAINS.

SUNDAY NIGHT...CONTINUED BREEZY TO WINDY PER PROGGED SURFACE THROUGH
700 MB GRADIENTS...THOUGH NOT AS WINDY AS SATURDAY NIGHT. COLD AND
BLUSTERY WITH OROGRAPHIC SNOWS CONTINUING IN MOIST FLOW OVER THE
SNOWY AND SIERRA MADRE RANGES.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 342 AM MST SAT NOV 22 2014

ONGOING SNOW EVENT OVR THE SNOWY AND SIERRA MADRE RANGES WILL KICK
OFF THE PERIOD AS TRAILING SHORTWAVE TROUGH IN NORTHWEST FLOW CLIPS
THE AREA. MOUNTAINS LOCATIONS WILL SEE AN ADDITIONAL 3 TO 6 INCHES
ON MONDAY. THESE RATES WILL CONTINUE TO WARRANT THE AFOREMENTIONED
WINTER STORM WARNING OVR THE MOUNTAINS. POST-FRONTAL NORTHWEST FLOW
WILL NOT BE ALL THAT FAVORABLE FOR PRECIP OUTSIDE OF OROGRAPHIC
AREAS...HOWEVER MAY SEE NW/SE ORIENTED SNOW BANDS SET UP...
ESPECIALLY DURING THE AFTERNOON HOURS. POST FRONTAL LLVL CAA WILL
YIELD HIGHS MONDAY ONLY IN THE 20S WEST OF THE LARAMIE RANGE...WITH
30S ON THE ERN PLAINS. IT WILL FEEL MUCH COLDER HOWEVER...WITH
NORTHWEST WINDS GUSTING TO 35-45 MPH AT TIMES. DEPENDING UPON THE
AMOUNT OF CLEARING/MIXING...AREAS IN THE PANHANDLE MAY NEED A WIND
ADVISORY IN TIME.

NW FLOW WILL CONTINUE ON TUESDAY. OROGRAPHICALLY FAVORED AREAS WILL
STILL SEE LT SNOW...HOWEVER RATES SHOULD NO LONGER NECESSITATE A
WINTER HIGHLIGHT. ANY SNOW CHANCES WILL AGAIN STRUGGLE TO PULL AWAY
FROM THE MTNS...ESPECIALLY DURING THE DAYTIME HOURS. THE ECMWF DOES
HINT THAT SNOW CHANCES WILL SPILL OUT ONTO THE PLAINS TUESDAY NIGHT.
THE GFS IS LESS AGGRESSIVE WITH THIS IDEA HOWEVER...CONFINING
CHANCES TO THE MOUNTAINS TUESDAY NIGHT. ANOTHER DAY OF BREEZY WEST
WINDS ACROSS THE CWFA TUESDAY WITH GUSTS AGAIN 30-40 MPH.

MEDIUM RANGE MODELS CONTINUE TO STRUGGLE WED-SAT...WITH THE MILLION
DOLLAR QUESTION CENTERING AROUND THE POSSIBILITY OF AN ARCTIC
BOUNDARY BCMNG STATIONARY WED NIGHT AND THU. MODELS ARE NOTORIOUS
FOR STRUGGLING IN THE DEPTH OF COLD AIR MASS THIS FAR OUT. THE 00Z
ECMWF IS MUCH MORE AMPLIFIED WITH A BUILDING RIDGE ALONG THE WEST
COAST...WHILE THE GFS IS SIGNIFICANTLY FLATTER. SO DESPITE SOME
SOLUTION CONGRUENCY IN YESTERDAYS 12Z MODEL SUITES...DIFFERENCES
REAR THEIR UGLY HEAD ONCE AGAIN IN 00Z DATA. FOR NOW...HAVE KEPT
THINGS RELATIVELY DRY AND MILD...FAVORING THE MORE CONSISTENT ECMWF.
HOWEVER...IF TRENDS TURN TOWARDS THE GFS COULD SEE A PERIOD OF SNOW
WED NT/THU ALONG WITH A COOLER THANKSGIVING DAY. STAY TUNED.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1031 AM MST SAT NOV 22 2014

VERY WINDY CONDITIONS ACROSS SOUTHEAST WYOMING WITH GUSTY WINDS IN
THE PANHANDLE. LOOK FOR DETERIORORATING CONDITIONS OUT NEAR KRWL
LATER THIS AFTERNOON AS RAIN SHOWERS TURN OVER TO SNOW. THESE
LOWERING CONDITIONS COULD IMPACT THE PANHANDLE AIRPORTS TONIGHT AS
LATEST GUIDANCE DOES SHOW SHOWERS DEVELOPING OUT THERE OVERNIGHT.

&&

.FIRE WEATHER...
ISSUED AT 342 AM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG TODAY AND TONIGHT...MINIMAL FIRE
WEATHER CONCERNS DUE TO COOL TEMPERATURES AND HIGHER HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO 5 PM MST MONDAY
     FOR WYZ112-114.

     HIGH WIND WARNING UNTIL 5 AM MST SUNDAY FOR WYZ101-103>106-110-
     116-117.

     HIGH WIND WARNING UNTIL 5 AM MST SUNDAY FOR WYZ107-115-118.

NE...NONE.
&&

$$

SHORT TERM...RUBIN
LONG TERM...CAH
AVIATION...GCC
FIRE WEATHER...RUBIN



000
FXUS65 KCYS 222114
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
215 PM MST SAT NOV 22 2014

.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 342 AM MST SAT NOV 22 2014

TODAY...INHERITED WIND AND SNOW HIGHLITES LOOK ON TRACK. FOR
WIND...ARLINGTON ALREADY SEEING SUSTAINED 45 MPH WITH GUSTS IN THE
MID 50S. WINDS EXPECTED TO CONTINUE TO RAMP UP AS 850/700 MB CRAIG
TO CASPER HEIGHT GRADIENTS RISE TO NEAR 70 METERS BY LATE AFTERNOON.
BASED ON LOW AND MID LEVEL HEIGHT GRADIENTS...INHERITED HIGH WIND
WARNING ON TRACK...AND WILL UPGRADE THE HIGH WIND WATCH TO A WARNING
FOR LATE MORNING AND LATER TODAY FOR CHEYENNE...PLATTE AND CONVERSE
COUNTIES AS AGREE WITH DAY SHIFT REASONING FROM YESTERDAY. PROGGED
SURFACE THROUGH 700 MB GRADIENTS LOOK FAVORABLE. OROGRAPHIC SNOWS
EXPECTED TO CRANK UP LATE THIS AFTERNOON OVER THE SNOWY AND SIERRA
MADRE RANGES AS A PACIFIC COLD FRONT ENTERS THE REGION. FORECAST QPF
AND OROGRAPHICS SUGGEST AN UPGRADE TO A WINTER STORM WARNING THERE.

TONIGHT...STRONG BORA WINDS CONTINUE IN THE POST COLD FRONTAL
AIRMASS AND THUS THE CONTINUATION OF THE HIGH WIND WARNING. HEIGHT
GRADIENTS DECREASE THUS SLOWLY DECREASING WINDS. MODERATE TO HEAVY
SNOW WILL CONTINUE OVER THE SNOWY AND SIERRA MADRE RANGES IN MOIST
OROGRAPHIC FLOW.

SUNDAY...BLUSTERY AND WINDY DAY IN THE WAKE OF THE COLD FRONT WITH
OROGRAPHIC SNOWS IN EARNEST CONTINUING OVER THE SOUTHWEST MOUNTAINS.

SUNDAY NIGHT...CONTINUED BREEZY TO WINDY PER PROGGED SURFACE THROUGH
700 MB GRADIENTS...THOUGH NOT AS WINDY AS SATURDAY NIGHT. COLD AND
BLUSTERY WITH OROGRAPHIC SNOWS CONTINUING IN MOIST FLOW OVER THE
SNOWY AND SIERRA MADRE RANGES.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 342 AM MST SAT NOV 22 2014

ONGOING SNOW EVENT OVR THE SNOWY AND SIERRA MADRE RANGES WILL KICK
OFF THE PERIOD AS TRAILING SHORTWAVE TROUGH IN NORTHWEST FLOW CLIPS
THE AREA. MOUNTAINS LOCATIONS WILL SEE AN ADDITIONAL 3 TO 6 INCHES
ON MONDAY. THESE RATES WILL CONTINUE TO WARRANT THE AFOREMENTIONED
WINTER STORM WARNING OVR THE MOUNTAINS. POST-FRONTAL NORTHWEST FLOW
WILL NOT BE ALL THAT FAVORABLE FOR PRECIP OUTSIDE OF OROGRAPHIC
AREAS...HOWEVER MAY SEE NW/SE ORIENTED SNOW BANDS SET UP...
ESPECIALLY DURING THE AFTERNOON HOURS. POST FRONTAL LLVL CAA WILL
YIELD HIGHS MONDAY ONLY IN THE 20S WEST OF THE LARAMIE RANGE...WITH
30S ON THE ERN PLAINS. IT WILL FEEL MUCH COLDER HOWEVER...WITH
NORTHWEST WINDS GUSTING TO 35-45 MPH AT TIMES. DEPENDING UPON THE
AMOUNT OF CLEARING/MIXING...AREAS IN THE PANHANDLE MAY NEED A WIND
ADVISORY IN TIME.

NW FLOW WILL CONTINUE ON TUESDAY. OROGRAPHICALLY FAVORED AREAS WILL
STILL SEE LT SNOW...HOWEVER RATES SHOULD NO LONGER NECESSITATE A
WINTER HIGHLIGHT. ANY SNOW CHANCES WILL AGAIN STRUGGLE TO PULL AWAY
FROM THE MTNS...ESPECIALLY DURING THE DAYTIME HOURS. THE ECMWF DOES
HINT THAT SNOW CHANCES WILL SPILL OUT ONTO THE PLAINS TUESDAY NIGHT.
THE GFS IS LESS AGGRESSIVE WITH THIS IDEA HOWEVER...CONFINING
CHANCES TO THE MOUNTAINS TUESDAY NIGHT. ANOTHER DAY OF BREEZY WEST
WINDS ACROSS THE CWFA TUESDAY WITH GUSTS AGAIN 30-40 MPH.

MEDIUM RANGE MODELS CONTINUE TO STRUGGLE WED-SAT...WITH THE MILLION
DOLLAR QUESTION CENTERING AROUND THE POSSIBILITY OF AN ARCTIC
BOUNDARY BCMNG STATIONARY WED NIGHT AND THU. MODELS ARE NOTORIOUS
FOR STRUGGLING IN THE DEPTH OF COLD AIR MASS THIS FAR OUT. THE 00Z
ECMWF IS MUCH MORE AMPLIFIED WITH A BUILDING RIDGE ALONG THE WEST
COAST...WHILE THE GFS IS SIGNIFICANTLY FLATTER. SO DESPITE SOME
SOLUTION CONGRUENCY IN YESTERDAYS 12Z MODEL SUITES...DIFFERENCES
REAR THEIR UGLY HEAD ONCE AGAIN IN 00Z DATA. FOR NOW...HAVE KEPT
THINGS RELATIVELY DRY AND MILD...FAVORING THE MORE CONSISTENT ECMWF.
HOWEVER...IF TRENDS TURN TOWARDS THE GFS COULD SEE A PERIOD OF SNOW
WED NT/THU ALONG WITH A COOLER THANKSGIVING DAY. STAY TUNED.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1031 AM MST SAT NOV 22 2014

VERY WINDY CONDITIONS ACROSS SOUTHEAST WYOMING WITH GUSTY WINDS IN
THE PANHANDLE. LOOK FOR DETERIORORATING CONDITIONS OUT NEAR KRWL
LATER THIS AFTERNOON AS RAIN SHOWERS TURN OVER TO SNOW. THESE
LOWERING CONDITIONS COULD IMPACT THE PANHANDLE AIRPORTS TONIGHT AS
LATEST GUIDANCE DOES SHOW SHOWERS DEVELOPING OUT THERE OVERNIGHT.

&&

.FIRE WEATHER...
ISSUED AT 342 AM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG TODAY AND TONIGHT...MINIMAL FIRE
WEATHER CONCERNS DUE TO COOL TEMPERATURES AND HIGHER HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO 5 PM MST MONDAY
     FOR WYZ112-114.

     HIGH WIND WARNING UNTIL 5 AM MST SUNDAY FOR WYZ101-103>106-110-
     116-117.

     HIGH WIND WARNING UNTIL 5 AM MST SUNDAY FOR WYZ107-115-118.

NE...NONE.
&&

$$

SHORT TERM...RUBIN
LONG TERM...CAH
AVIATION...GCC
FIRE WEATHER...RUBIN



000
FXUS65 KRIW 222110
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
210 PM MST SAT NOV 22 2014

.SHORT TERM...TONIGHT THROUGH SUNDAY

A PACIFIC COLD FRONT APPROACHING WESTERN WYOMING WILL MOVE THROUGH
WESTERN AND CENTRAL WYOMING THROUGH THE NIGHT.  THE SNOW INTENSITIES
WILL DECREASE WITH THE PASSING OF THE COLD FRONT IN THE WESTERN
M0MOUNTAINS.  MOST AREAS EXPERIENCING HIGH WINDS TODAY WILL SEE
WINDS DECREASE AS THEY SHIFT TO THE NORTHWEST. HIGH WIND WATCHES
REMAIN FOR NORTHERN JOHNSON AND THE WIND RIVER BASIN WITH THE
NORTHWEST WINDS AS THESE AREAS FAVOR HIGH WINDS WITH NORTHWEST
WINDS AND COLD AIR ADVECTION. AREAS EAST OF THE CONTINENTAL DIVIDE
CAN EXPECT A QUICK BURST OF SNOWFALL BEHIND THE COLD FRONT WITH
LIGHT ACCUMULATIONS. OVERALL SNOWFALL WILL BE TAPERING OFF
THROUGH THE MORNING WITH SOME LINGERING MOUNTAIN SNOW SHOWERS ON
SUNDAY. TEMPERATURES WILL COOL ABOUT TEN DEGREES FROM TODAY.

.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY

BEHIND THE MAIN SHORTWAVE THAT WILL BE SWINGING THROUGH THIS
WEEKEND...A SECONDARY PIECE OF ENERGY WILL BE SLIDING DOWN THE BACK
SIDE OF THE MAIN TROUGH AXIS ACROSS THE CWA FAIRLY QUICKLY AROUND
12Z MONDAY. WITH WEAK ISENTROPIC LIFT IN THE WEST AHEAD OF THIS
SYSTEM AS WELL AS SOME WEAK QG FORCING IN THE SOUTHWEST...KEPT IDEA
OF ANOTHER 3 TO 6 INCHES OF SNOWFALL IN THE WESTERN MTNS SUNDAY INTO
MONDAY ALONG WITH ANOTHER 2 TO 3 INCHES IN THE WESTERN VALLEYS. THE
SNOW INTENSITY WILL BEGIN TO DECREASE MONDAY AFTERNOON. DURING THE
TROUHPA...AROUND 12Z MONDAY...THERE WILL BE A BRIEF PERIOD WHEN THE
SNOWFALL SPILLS OVER TO AREAS EAST OF THE DIVIDE WITH THE MOST
SIGNIFICANT SNOWFALL OCCURRING IN THE BIG HORN MTNS WHERE 3 TO 5
INCHES ARE EXPECTED. THE SNOWFALL WILL DECREASE EAST OF THE DIVIDE
IN THE AFTERNOON AS WELL.

THE NEXT ANTICIPATED SNOW EVENT WILL OCCUR WHEN THE JET STREAM
SHIFTS NORTHEAST PLACING THE FASTER NORTHWEST FLOW ALOFT OVER
WYOMING BY 12Z TUESDAY. THIS WILL DRAW IN ADDITIONAL PACIFIC
MOISTURE FROM THE NORTHWEST ALONG WITH ISENTROPIC LIFT OVER WESTERN
WY TUESDAY WITH AN EXTENSIVE AREA OF ISENTROPIC LIFT SHIFTING TO OUR
NORTH OVER MONTANA BY TUESDAY NIGHT. THIS WILL JUSTIFY LIKELY POPS
IN THE WESTERN/BIG HORN MTNS AS WELL AS CHC POPS OVER THE NORTH HALF
OF THE LOWER ELEVATIONS OF THE CWA TUE/TUE NIGHT. THE JET STREAM
WILL THEN SHIFT NORTHEAST OF THE CWA BY WEDNESDAY.

AFTER THIS TIME FRAME...THE MODELS DIVERGE ONCE AGAIN WITH THE EURO
NOW THE MORE OPTIMISTIC MODEL PLACING A RIDGE OVER WY BY THURSDAY
AND THE GFS KEEPING THE DIRTY NORTHWEST FLOW OVER US THROUGH FRIDAY
WHICH IS IRONIC BECAUSE A COUPLE OF DAYS AGO BOTH THESE MODELS
PORTRAYED OPPOSITE SOLNS WITH THE GFS ADVERTISING A BUILDING RIDGE
AND THE EURO A POTENTIAL SNOW EVENT FOR THANKSGIVING. WITH THE
MODELS FLIP FLOPPING AND NO RUN TO RUN CONSISTENCY...ALL WE ARE
GOING TO DO IS INCREASE THE POPS A TAD OVER MAINLY NW WY FOR THE
SECOND HALF OF NEXT WEEK JUST IN CASE A SNOW EVENT DOES TAKE PLACE
DURING THIS TIME FRAME. MORE SPECIFICALLY...THE GFS PULLS IN COLDER
AIR FROM THE NORTHEAST OVER WY WITH MOST OF THE ASCT ISENTROPIC LIFT
FROM THIS ASCT WEATHER DISTURBANCE REMAINING TO OUR NORTH UP IN MT.

BY FRIDAY NIGHT...THE NW FLOW WILL BACK TO THE WEST AS THE RIDGE
FLATTENS. A MINOR DISTURBANCE MOVING THROUGH THE FLATTENING RIDGE
WITH ITS SHARE OF ISENTROPIC LIFT COULD BRING SOME LIGHT SNOW TO THE
FAR WEST SATURDAY.

TEMPERATURES NEXT WEEK WILL DEPEND LARGELY UPON WHETHER THE GFS OR
THE EURO PANS OUT SO KIND OF WENT WITH A BLEND. IN ANY EVENT...TEMPS
WILL BE MUCH MILDER THAN THEY HAVE BEEN DURING THE LAST COUPLE OF
WEEKS GIVEN THE LACK OF ANY ARCTIC INTRUSIONS NEXT WEEK.

&&

.AVIATION.../00Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES

AREAS OF LLWS WILL CONTINUE OVER THE CENTRAL BASINS AS WEST WINDS
FL070-100 BETWEEN 45-50KTS THROUGH 06Z. THESE STRONGER WINDS WILL
MIX DOWN TO THE SURFACE FROM VCNTY 50NE SM KRKS-KCPR AND FROM
VCNTY KCOD- KDUB WHERE HIGH WIND WARNINGS ARE IN EFFECT. A STRONG
COLD FRONT WILL PUSH ACROSS THE AREA EARLY THIS EVENING. MTNS WILL
BE MOSTLY OBSCURED ALONG THE DIVIDE AHEAD OF THE FRONT WITH SOME
BLOW OVER PCPN IN THE VCNTY OF KLND-KCOD. A BAND OF SNOW WILL
LIKELY ACCOMPANY THE FRONT THIS EVENING ALONG WITH AREAS OF
MVFR/IFR -SN MAINLY VCNTY ALONG AND EAST OF THE BIGHORN RANGE AND
INTERSTATE 25. AREAS OF SFC NW WINDS AT 20-30KTS WITH GUSTS TO
40KTS WILL FOLLOW THE FRONT...DECREASING AFTER 06Z.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES

MVFR/IFR CEILINGS AND VISIBILITIES REDUCED IN SNOW...BLOWING SNOW
AND FOG WILL CONTINUE ACROSS THE WEST THROUGH 18Z SUNDAY.  LLWS
WILL ALSO PERSIST ACROSS THE AREA AS FL070-100 WINDS BTWN
40-50KTS. A STRONG COLD FRONT WILL PUSH ACROSS THE AREA THIS
AFTERNOON AND EVENING WITH AREAS OF WEST SFC WIND 20-30KTS WITH
GUSTS TO 40KTS. MVFR/IFR CEILINGS AND VISIBILITIES WILL DECREASE
ACROSS THE WEST FROM 12Z THROUGH 18Z SUNDAY.

&&

.FIRE WEATHER...

SNOWFALL WILL CONTINUE MOST MOUNTAIN AREAS TONIGHT AND THEN
DECREASE THROUGH SUNDAY AS A COLD FRONT PASSES THROUGH.  STRONG WINDS
WILL CONTINUE EARLY THIS EVENING AND THEN DIMINISH. BEHIND THE
COLD FRONT EARLY SUNDAY...HIGH WINDS MAY DEVELOP IN THE WIND
RIVER BASIN AND NORTHERN JOHNSON COUNTIES AS THESE AREAS FAVOR
STRONGER WINDS IN NORTHWEST FLOW. TEMPERATURES WILL BE COLDER WITH
HIGHER HUMIDITY AND LOW MIXING HEIGHTS WITH POOR SMOKE DISPERSAL.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL MIDNIGHT MST TONIGHT WYZ003-019-020-022.

WINTER WEATHER ADVISORY UNTIL 6 AM MST SUNDAY WYZ016-026-027.

WINTER STORM WARNING UNTIL 6 AM MST SUNDAY
WYZ001-002-012>015-023>025.

HIGH WIND WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
WYZ010.

HIGH WIND WATCH FROM SUNDAY MORNING THROUGH SUNDAY AFTERNOON
WYZ016-017.

&&

$$

SHORT TERM...C.BAKER
LONG TERM...LIPSON
AVIATION...C.BAKER
FIRE WEATHER...C.BAKER








000
FXUS63 KUNR 221744
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1044 AM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 835 AM MST SAT NOV 22 2014

POTENT NW CONUS UPPER TROUGH CONTINUES TO ADVECT EAST INTO THE
NORTHERN PLAINS. TIMING OF UVM LOOKS OT BE A LITTLE EARLIER THAN
PREVIOUS GUIDANCE SUGGESTED. GIVEN UPSTREAM OB TRENDS...WENT AHEAD
AND INCREASED POPS THIS AFTERNOON FAR NW. OTHERWISE...WENT AHEAD
AND ISSUED A HIGH WIND WATCH FOR NW SD SUNDAY GIVEN
MOMENTUM/MIXING PROGS. WIND GUSTS TO AROUND 60 LOOK LIKELY ACROSS
FAR NW SD...AND POSSIBLE AS FAR SOUTH AS RAPID CITY.

&&

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
ISSUED AT 301 AM MST SAT NOV 22 2014

AN ACTIVE WESTERLY FLOW ALOFT DOMINATES THE LARGE
SCALE FOR THE NORTHERN U.S. THIS MORNING.  WEAK IMPULSES EMBEDDED IN
THE FLOW ARE MOVING INTO THE NORTHERN PLAINS PRODUCING SOME VERY
LIGHT PRECIPITATION EAST OF THE CONTDVD...BUT NO SIGNIFICANT FRONTAL
BOUNDARIES ARE IN THE ANALYSIS ACROSS THE NORTHERN PLAINS OR
NORTHERN ROCKIES. EARLY MORNING TEMPERATURES ACROSS THE NORTHERN
PLAINS ARE SEASONABLY MILD BUT WARM CONSIDERABLY TO THE WEST IN THE
NORTHERN INTERMOUNTAIN REGION. A VIGOROUS FAST MOVING PACIFIC SHORT
WAVE WAS MOVING ONSHORE AT 09Z. A SPLIT FLOW OVER THE SOUTHERN GREAT
BASIN HAS PRETTY MUCH CUT OFF THE HIGH AMPLITUDE TROUGH OVER THE
SOUTHWESTERN U.S. AND NORTHERN MEXICO WHICH IS MAKING SLOW PROGRESS
EASTWARD.

TODAY...ANOTHER DAY OF ABOVE NORMAL TEMPERATURES IS IN STORE FOR
NORTHEAST WYOMING AND WESTERN SOUTH DAKOTA TODAY.  THE APPROACHING
WEATHER SYSTEM WILL PRODUCE INCREASING HIGH CLOUDS FROM MID MORNING
ONWARD...BUT MAXIMUM TEMPERATURES ARE STILL EXPECTED TO BE AT LEAST
A COUPLE DEGREES HIGHER THAN YESTERDAY.  A FEW LIGHT RAIN SHOWERS
ARE POSSIBLE OVER NORTHEAST WYOMING AND THE BLKHLS REGION LATE THIS
AFTERNOON WITH THE DCVA FROM THE APPROACHING SYSTEM.

TONIGHT...THE MAIN PRECIPITATION EVENT WILL BEGIN DURING THE LATE
EVENING HOURS AS THE FAST MOVING COLD FRONT MOVES INTO THE PLAINS.
THE PRECIP WILL FALL AS RAIN INITIALLY THEN BECOME MIXED WITH SNOW
AFTER 06Z AND BE ALL SNOW BY EARLY SUNDAY MORNING.  DEPENDING ON
WHEN THE SWITCHOVER ACTUALLY OCCURS THE HIGHER ELEVATIONS OF THE
BLKHLS AND NORTHEAST WYOMING COULD SEE FROM 4 TO 8 INCHES OF NEW
SNOW BY EARLY SUNDAY.

SUNDAY...THE PACIFIC TROUGH IS FORECAST TO BEGIN SPLITTING AND
SLOWING DOWN AS IT MOVES INTO THE PLAINS EARLY SUNDAY.  THIS
EVOLUTION WILL CREATE A PERIOD OF STRONG NORTHERLY SURFACE FLOW
...ESPECIALLY ACROSS WESTERN SOUTH DAKOTA...BY MIDDAY SUNDAY. THE
WINDS AND COLDER TEMPERATURES WILL BECOME THE MAIN WEATHER STORY ON
SUNDAY AS DYNAMICS TO SUPPORT THE LIGHT SNOW WILL GRADUALLY FADE.
WIND SPEEDS MEETING HIGH WIND CRITERIA ARE A POSSIBILITY EARLY
SUNDAY AFTERNOON.

SUNDAY NIGHT...LIGHT SNOW SHOWERS WILL CONTINUE THROUGH THE
OVERNIGHT HOURS BEHIND THE MAIN WEATHER SYSTEM WITH LITTLE
ACCUMULATION. MID LEVEL COLD ADVECTION AND A FEW WEAK EMBEDDED
IMPULSES WILL CONTINUE ALL NIGHT.

&&

.LONG TERM...MONDAY THROUGH FRIDAY
ISSUED AT 301 AM MST SAT NOV 22 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. SEVERAL WEAK DISTURBANCES WITHIN THE NORTHWEST FLOW WILL
BRING CLOUDS AND CHANCES FOR SNOW AT TIMES THROUGH TUESDAY. A COLD
FRONT WILL CROSS THE DAKOTAS WEDNESDAY...BRINGING COOLER TEMPS
ACROSS MOST AREAS. SNOW IS ALSO EXPECTED TO DEVELOP ALONG THE
BAROCLINIC ZONE...ESPECIALLY ACROSS NE WY AND PORTIONS OF FAR WRN
SD.

THERE IS STILL UNCERTAINTY TOWARD THE LATTER PART OF NEXT
WEEK...WITH LONGER RANGE MODELS CONTINUING TO FIGURE OUT WHAT TYPE
OF AIRMASS WILL BE OVER THE AREA. MODELS HAVE BEEN SHOWING WARMER
AIR ADVECTING IN WITH THE FRONTAL BOUNDARY SLIDING EAST OF THE
CWA...BUT THE 00Z GFS HAS TRENDED BACK TO A COLDER SOLUTION WHILE
THE 00Z ECM HAS TRENDED WARMER. WILL STICK WITH TEMPS IN THE MIDDLE
OF ALL SOLUTIONS.

&&

.AVIATION...FOR THE 18Z TAFS THROUGH 18Z SUNDAY
ISSUED AT 1043 AM MST SAT NOV 22 2014

VFR CONDITIONS EXPECTED THROUGH THIS AFTERNOON. GUSTY WEST-SOUTHWEST
WINDS WILL CONTINUE ACROSS NORTHEAST WY/HIGHER ELEVATIONS OF THE
BLACK HILLS THIS AFTERNOON. A COLD FRONT WILL CROSS THE AREA
TONIGHT...WITH BREEZY NORTHWEST WINDS DEVELOPING BEHIND THE FRONT.
CHANCES FOR RAIN SHOWERS ARE EXPECTED LATE THIS AFTERNOON AND
EVENING OVER MAINLY NORTHEAST WY AND FAR WESTERN SD...CHANGING TO
SNOW SHOWERS OVERNIGHT. STRONGER NORTHWEST WINDS WILL DEVELOP
SUNDAY MORNING.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...HIGH WIND WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR
     SDZ001-002-012-013-025-026-031-072-073.

WY...NONE.
&&

$$

UPDATE...JC
SHORT TERM...CARPENTER
LONG TERM...13
AVIATION...26






000
FXUS65 KCYS 221734
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1034 AM MST SAT NOV 22 2014

.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 342 AM MST SAT NOV 22 2014

TODAY...INHERITED WIND AND SNOW HIGHLITES LOOK ON TRACK. FOR
WIND...ARLINGTON ALREADY SEEING SUSTAINED 45 MPH WITH GUSTS IN THE
MID 50S. WINDS EXPECTED TO CONTINUE TO RAMP UP AS 850/700 MB CRAIG
TO CASPER HEIGHT GRADIENTS RISE TO NEAR 70 METERS BY LATE AFTERNOON.
BASED ON LOW AND MID LEVEL HEIGHT GRADIENTS...INHERITED HIGH WIND
WARNING ON TRACK...AND WILL UPGRADE THE HIGH WIND WATCH TO A WARNING
FOR LATE MORNING AND LATER TODAY FOR CHEYENNE...PLATTE AND CONVERSE
COUNTIES AS AGREE WITH DAY SHIFT REASONING FROM YESTERDAY. PROGGED
SURFACE THROUGH 700 MB GRADIENTS LOOK FAVORABLE. OROGRAPHIC SNOWS
EXPECTED TO CRANK UP LATE THIS AFTERNOON OVER THE SNOWY AND SIERRA
MADRE RANGES AS A PACIFIC COLD FRONT ENTERS THE REGION. FORECAST QPF
AND OROGRAPHICS SUGGEST AN UPGRADE TO A WINTER STORM WARNING THERE.

TONIGHT...STRONG BORA WINDS CONTINUE IN THE POST COLD FRONTAL
AIRMASS AND THUS THE CONTINUATION OF THE HIGH WIND WARNING. HEIGHT
GRADIENTS DECREASE THUS SLOWLY DECREASING WINDS. MODERATE TO HEAVY
SNOW WILL CONTINUE OVER THE SNOWY AND SIERRA MADRE RANGES IN MOIST
OROGRAPHIC FLOW.

SUNDAY...BLUSTERY AND WINDY DAY IN THE WAKE OF THE COLD FRONT WITH
OROGRAPHIC SNOWS IN EARNEST CONTINUING OVER THE SOUTHWEST MOUNTAINS.

SUNDAY NIGHT...CONTINUED BREEZY TO WINDY PER PROGGED SURFACE THROUGH
700 MB GRADIENTS...THOUGH NOT AS WINDY AS SATURDAY NIGHT. COLD AND
BLUSTERY WITH OROGRAPHIC SNOWS CONTINUING IN MOIST FLOW OVER THE
SNOWY AND SIERRA MADRE RANGES.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 342 AM MST SAT NOV 22 2014

ONGOING SNOW EVENT OVR THE SNOWY AND SIERRA MADRE RANGES WILL KICK
OFF THE PERIOD AS TRAILING SHORTWAVE TROUGH IN NORTHWEST FLOW CLIPS
THE AREA. MOUNTAINS LOCATIONS WILL SEE AN ADDITIONAL 3 TO 6 INCHES
ON MONDAY. THESE RATES WILL CONTINUE TO WARRANT THE AFOREMENTIONED
WINTER STORM WARNING OVR THE MOUNTAINS. POST-FRONTAL NORTHWEST FLOW
WILL NOT BE ALL THAT FAVORABLE FOR PRECIP OUTSIDE OF OROGRAPHIC
AREAS...HOWEVER MAY SEE NW/SE ORIENTED SNOW BANDS SET UP...
ESPECIALLY DURING THE AFTERNOON HOURS. POST FRONTAL LLVL CAA WILL
YIELD HIGHS MONDAY ONLY IN THE 20S WEST OF THE LARAMIE RANGE...WITH
30S ON THE ERN PLAINS. IT WILL FEEL MUCH COLDER HOWEVER...WITH
NORTHWEST WINDS GUSTING TO 35-45 MPH AT TIMES. DEPENDING UPON THE
AMOUNT OF CLEARING/MIXING...AREAS IN THE PANHANDLE MAY NEED A WIND
ADVISORY IN TIME.

NW FLOW WILL CONTINUE ON TUESDAY. OROGRAPHICALLY FAVORED AREAS WILL
STILL SEE LT SNOW...HOWEVER RATES SHOULD NO LONGER NECESSITATE A
WINTER HIGHLIGHT. ANY SNOW CHANCES WILL AGAIN STRUGGLE TO PULL AWAY
FROM THE MTNS...ESPECIALLY DURING THE DAYTIME HOURS. THE ECMWF DOES
HINT THAT SNOW CHANCES WILL SPILL OUT ONTO THE PLAINS TUESDAY NIGHT.
THE GFS IS LESS AGGRESSIVE WITH THIS IDEA HOWEVER...CONFINING
CHANCES TO THE MOUNTAINS TUESDAY NIGHT. ANOTHER DAY OF BREEZY WEST
WINDS ACROSS THE CWFA TUESDAY WITH GUSTS AGAIN 30-40 MPH.

MEDIUM RANGE MODELS CONTINUE TO STRUGGLE WED-SAT...WITH THE MILLION
DOLLAR QUESTION CENTERING AROUND THE POSSIBILITY OF AN ARCTIC
BOUNDARY BCMNG STATIONARY WED NIGHT AND THU. MODELS ARE NOTORIOUS
FOR STRUGGLING IN THE DEPTH OF COLD AIR MASS THIS FAR OUT. THE 00Z
ECMWF IS MUCH MORE AMPLIFIED WITH A BUILDING RIDGE ALONG THE WEST
COAST...WHILE THE GFS IS SIGNIFICANTLY FLATTER. SO DESPITE SOME
SOLUTION CONGRUENCY IN YESTERDAYS 12Z MODEL SUITES...DIFFERENCES
REAR THEIR UGLY HEAD ONCE AGAIN IN 00Z DATA. FOR NOW...HAVE KEPT
THINGS RELATIVELY DRY AND MILD...FAVORING THE MORE CONSISTENT ECMWF.
HOWEVER...IF TRENDS TURN TOWARDS THE GFS COULD SEE A PERIOD OF SNOW
WED NT/THU ALONG WITH A COOLER THANKSGIVING DAY. STAY TUNED.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1031 AM MST SAT NOV 22 2014

VERY WINDY CONDITIONS ACROSS SOUTHEAST WYOMING WITH GUSTY WINDS IN
THE PANHANDLE. LOOK FOR DETERIORORATING CONDITIONS OUT NEAR KRWL
LATER THIS AFTERNOON AS RAIN SHOWERS TURN OVER TO SNOW. THESE
LOWERING CONDITIONS COULD IMPACT THE PANHANDLE AIRPORTS TONIGHT AS
LATEST GUIDANCE DOES SHOW SHOWERS DEVELOPING OUT THERE OVERNIGHT.

&&

.FIRE WEATHER...
ISSUED AT 342 AM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG TODAY AND TONIGHT...MINIMAL FIRE
WEATHER CONCERNS DUE TO COOL TEMPERATURES AND HIGHER HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO 5 PM MST MONDAY
     FOR WYZ112-114.

     HIGH WIND WARNING UNTIL 5 AM MST SUNDAY FOR WYZ101-103>106-110-
     116-117.

     HIGH WIND WARNING UNTIL 5 AM MST SUNDAY FOR WYZ107-115-118.

NE...NONE.
&&

$$

SHORT TERM...RUBIN
LONG TERM...CAH
AVIATION...GCC
FIRE WEATHER...RUBIN



000
FXUS65 KRIW 221723
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1023 AM MST SAT NOV 22 2014

.SHORT TERM...SATURDAY THROUGH MONDAY NIGHT

WITH THE DIFFERENCES IN THE WEATHER ACROSS THE AREA WE WILL DIVIDE
THE DISCUSSION INTO WEST OF THE DIVIDE AND EAST OF THE DIVIDE.

WEST OF THE DIVIDE...IT LOOKS LIKE AN ACTIVE 36 HOURS OR SO AS THE
NEXT WEATHER MAKER NOW OVER IDAHO IN THE FORM OF A COLD FRONT AND
ASSOCIATED TROUGH MAKES ITS WAY TOWARD THE AREA. RADAR OUT OF OUR
NEIGHBORS TO THE WEST SHOW SOME SNOW MOVING INTO THE WESTERN
MOUNTAINS AND THE WEB CAMS CONFIRM THIS. THERE STILL LOOK TO BE TWO
DIFFERENT PARTS TO THIS SYSTEM. THE FIRST WILL BE THE WARM ADVECTION
THAT FALLS THIS MORNING. THE SECOND WILL BE THEN PASSAGE OF THE COLD
FRONT. THE MODELS CONTINUE TO BE IN FAIRLY GOOD AGREEMENT IN
BRINGING THE HEAVIEST PRECIPITATION FROM AROUND MID MORNING TO
AROUND EARLY AFTERNOON ACROSS MUCH OF THE AREA WITH THE FRONTAL
PASSAGE AND BEST UPPER LEVEL SUPPORT. CONTINUITY HANDLED THIS FAIRLY
WELL SO WE MADE FEW CHANGES TO THIS. THERE IS ONE CONCERN WE HAVE
HOWEVER. UNLIKE THE LAST SYSTEMS...THIS ONE IS PACIFIC IN ORIGIN AND
DOES NOT HAVE REALLY COLD AIR WITH IT. THE MODELS ARE SHOWING SOME
WARMER AIR THAT MAY ADVECT INTO THE WEST PRIOR TO THE PASSAGE OF THE
COLD FRONT. THE NAM SHOWS 700 MILLIBAR TEMPERATURES RISING TO AROUND
MINUS 3 THAT WOULD RAISE SNOW LEVELS TO AROUND 7000 FEET EARLY IN
THE AFTERNOON. THAT COULD LEAD TO SOME MIXING THAT COULD HOLD DOWN
ACCUMULATIONS. THE GFS IS COOLER BY ABOUT 1 TO 2 DEGREES CELSIUS AND
THAT WOULD KEEP THE PRECIPITATION MAINLY SNOW. FOR NOW...WE ALLOWED
FOR SOME MIXING IN SOME SOUTHERN PORTIONS OF THE HIGHLIGHT AREA
EARLY IN THE AFTERNOON BEFORE THE FRONTAL PASSAGE.

THE HEAVIEST SNOW SHOULD END THIS EVENING AS THE FORCING MOVES AWAY.
HOWEVER...WITH A SOMEWHAT MOIST WEST TO NORTHWESTERLY FLOW
CONTINUING OCCASIONAL SNOW WILL CONTINUE INTO TONIGHT AND INTO
TOMORROW AS WELL. TEMPERATURES WILL BE COLDER BUT NOT NEARLY AS COLD
AS LAST WEEK. ACCUMULATION WILL CONTINUE ALTHOUGH AT THIS POINT
ADDITIONAL AMOUNTS LOOK TO BE FAIRLY LIGHT. ANOTHER SPOKE OF ENERGY
IN THE FORM OF A SHORTWAVE COULD BRING SOME ADDITIONAL STEADIER SNOW
SUNDAY NIGHT AS WELL. WITH THE NORTHWEST FLOW CONTINUING SNOW
SHOWERS LOOK CONTINUE TO BE A GOOD BET RIGHT INTO MONDAY. AS ALWAYS
WITH NORTHWEST FLOW...THERE COULD BE A HEAVIER BAND THAT SETS UP BUT
PINPOINTING THESE IS IMPOSSIBLE. SOMETHING TO WATCH THOUGH.
TEMPERATURES ARE EXPECTED TO BE FAIRLY CLOSE TO NORMAL.

EAST OF THE DIVIDE...THE MAIN CONCERN HERE SHIFTS FROM THE THE WHITE
STUFF TO WIND. AHEAD OF THE COLD FRONT...IT LOOKS QUITE WINDY IN THE
FAVORED AREAS WITH SOUTHWEST FLOW. THE MODELS CONTINUE TO SHOW 50 TO
60 KNOTS ALOFT AND WITH SOME MIXING WE SHOULD SEE SOME WIND GUSTS TO
OVER 60 MPH ACROSS NATRONA COUNTY AS WELL AS THE RATTLESNAKE RANGE
AND CODY FOOTHILLS...ESPECIALLY NEAR THE GREAT CROSSROAD OF CLARK.
WINDS HAVE ALREADY GUSTED OVER 60 MPH THERE. WE THOUGHT ABOUT
DROPPING THE WARNING FOR CASPER MOUNTAIN...BUT WILL LEAVE IT FOR
NOW. AS FOR CHANCES OF PRECIPITATION...THEY LOOK FAIRLY SPARSE
DURING THE DAY AS DOWN SLOPING FLOW KEEPS THINGS DRY FOR MOST AREAS
EXCEPT THE MOUNTAINS. WE KEPT A SLIGHT CHANCE FOR MANY AREAS BUT
INCREASED IT TOWARD EVENING. THE EXCEPTION WOULD BE A PLACE LIKE
DUBOIS WHERE SOME BLOW OVER MAY BRING SNOW. THIS WILL ALSO BRING THE
WARMEST TEMPERATURES MANY AREAS HAVE SEEN SINCE A WEEK AGO ON
SUNDAY. THE GFS MOS NUMBERS ARE ESPECIALLY WARM...WARMING SOME AREAS
INTO THE 50S. WE KEPT THINGS A BUT COOLER FOR NOW THINKING THAT IF
IT GETS WARMER THAN THE PREDICTED HIGH TEMPERATURES...MOST PEOPLE
WILL BE HAPPY. IT WILL COOL OFF TONIGHT AFTER THE FRONT PASSES.
THERE IS THE CHANCE FOR SOME SNOW BANDS WITH THE NORTHWEST FLOW BUT
AGAIN THESE ARE IMPOSSIBLE TO PINPOINT UNTIL THEY FORM. SOMETHING TO
WATCH THOUGH.

WIND IS ONCE AGAIN THE PROBLEM FOR SUNDAY. HOWEVER...THE AREAS OF
CONCERN SWITCH TO THE FAVORED AREAS WITH NORTHWEST FLOW. THAT MEANS
PORTIONS OF NORTHERN JOHNSON COUNTY AS WELL AS THE WIND RIVER BASIN.
AGAIN WITH 700 MILLIBAR WINDS AROUND 50 KNOTS AS A RESULT WE HOISTED A
HIGH WIND WATCH FOR THESE AREAS FOR SUNDAY AND WILL CONTINUE IT AT
THIS TIME. THERE WILL STILL BE NORTHWEST FLOW AND CYCLONIC CURVATURE
OVER THE AREA AS WELL. THAT MEANS THE CHANCE FOR SOME SHOWERS
ALTHOUGH MOST AREAS SHOULD BE DRY MOST OF THE TIME. THE EXCEPTION
WOULD BE THE BIGHORN MOUNTAINS WHERE A FEW INCHES OF SNOW ARE
POSSIBLE. MONDAY LOOKS TO BE A SIMILAR DAY WITH SCATTERED SNOW
SHOWERS. WINDS SHOULD BE NOT QUITE AS STRONG...ALTHOUGH STILL GUSTY
FOR MOST AREAS.

.LONG TERM...TUESDAY THROUGH SATURDAY

MEDIUM RANGE MODELS START OUT IN PRETTY GOOD AGREEMENT BUT THEN
DIVERGE SIGNIFICANTLY FROM THANKSGIVING ONWARD. TO START THE
PERIOD ON TUESDAY...WE GET IN A DECENT ISENTROPIC UP GLIDE NW FLOW
PATTERN THAT COULD BRING SOME DECENT SNOW THE THE WRN AND NRN
MOUNTAINS TUESDAY INTO TUESDAY NIGHT. LIKELY POPS COVER THIS
PERIOD IN MOST OF THE WEST AND IN THE BIGHORN MTNS WITH A CHANCE
ACROSS THE LOWER ELEVATIONS OF THE NORTH. AFTER THAT...THE CHANGES
START. THE FIRST BIG DIFFERENCE IS HOW THE GULF OF ALASKA UPPER
LOW IS HANDLED. THE GFS TAKES THIS SYSTEM INLAND AND THEN SLIDES
IT SEWD DOWN THE BACK SIDE OF OUR RIDGE ALONG THE COAST RESULTING
IN A DECENT CHANCE OF SNOW WEDNESDAY NIGHT AND THURSDAY ACROSS ALL
BUT THE SW PART OF THE AREA. THE ECMWF WEAKENS THIS GULF OF ALASKA
LOW AS IT MOVES INLAND AND RUNS INTO THE CONFLUENT FLOW BETWEEN
THE WEST COAST RIDGE AND THE NNW FLOW FROM AROUND THE HUDSON BAY
LOW. ECMWF ENSEMBLES ALSO SUPPORT THE OP ECMWF. THE GEM SHOWS A
MORE GLANCING BLOW THAN THE GFS WITH WHAT`S LEFT OF THE GULF OF
ALASKA UPPER LOW WITH MAINLY A DRY FRONT CLIPPING THE NERN ZONES
WEDNESDAY NIGHT AND THURSDAY. LEANING MORE TOWARDS THE ECMWF EVEN
THOUGH IT HAS STRUGGLED OVER THE PAST SEVERAL DAYS. END RESULT FOR
OUR AREA IS WARMER TEMPERATURES FOR THANKSGIVING THAN THE GFS
WOULD INDICATE AND LITTLE IF ANY PCPN. WE WILL STILL NEED TO WATCH
IT CLOSELY. KEEPING SOME 20-30 POPS ACROSS THE WEST AND NORTH
WEDNESDAY NIGHT AND THEN DECREASING ON THANKSGIVING. FLAT RIDGE
HOLDS THROUGH THE END OF THE PERIOD WITH A POSSIBLE WEAK SHORTWAVE
MOVING IN ON SATURDAY FOR A CHANCE OF MTN SNOW IN THE WEST.
SHORTWAVE MOVING SOUTH TOWARDS THE NRN HIGH PLAINS MAY ALSO PUSH A
FRONT INTO THE NERN ZONES FRIDAY NIGHT AND SATURDAY.

.AVIATION.../18Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES

AREAS OF LLWS WILL CONTINUE OVER THE CENTRAL BASINS AS WEST WINDS
FL070-100 BETWEEN 45-50KTS. THESE STRONGER WINDS WILL MIX DOWN TO
THE SURFACE FROM VCNTY 50NE SM KRKS-KCPR AND FROM VCNTY KCOD- KDUB
WHERE HIGH WIND WARNINGS ARE IN EFFECT. A STRONG COLD FRONT WILL
PUSH ACROSS THE AREA EARLY THIS EVENING. MTNS WILL BE MOSTLY
OBSCURED ALONG THE DIVIDE AHEAD OF THE FRONT WITH SOME BLOW OVER
PCPN IN THE VCNTY OF KLND-KCOD.  A BAND OF SNOW WILL LIKELY
ACCOMPANY THE FRONT THIS EVENING ALONG WITH AREAS OF MVFR/IFR -SN MAINLY
VCNTY ALONG AND EAST OF THE BIGHORN RANGE AND INTERSTATE 25. AREAS
OF SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL FOLLOW THE
FRONT...DECREASING AFTER 06Z SUNDAY.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES

MVFR/IFR CEILINGS AND VISIBILITIES REDUCED IN SNOW...BLOWING SNOW
AND FOG WILL CONTINUE ACROSS THE WEST THROUGH 18Z SUNDAY.  LLWS
WILL ALSO PERSIST ACROSS THE AREA AS FL070-100 WINDS INCREASE TO
BTWN 40-50KTS. A STRONG COLD FRONT WILL PUSH ACROSS THE AREA
THIS AFTERNOON...AREAS OF WEST SFC WIND 20-30KTS WITH GUSTS TO
40KTS.

.FIRE WEATHER...

A WINTER WEATHER SYSTEM WILL IMPACT WESTERN WYOMING THROUGH TODAY.
ADDITIONALLY...STRONG WIND WILL OCCUR ACROSS THE WIND CORRIDOR
BETWEEN ROCK SPRINGS AND CASPER...AND WILL ALSO DEVELOP IN THE
CODY FOOTHILLS. HIGH WIND WARNINGS ARE IN EFFECT FOR MUCH OF THE
DAY TODAY FOR THESE LOCATIONS. FIRE WEATHER BEHAVIOR IS
EXPECTED TO REMAIN MINIMAL UNDER THIS SYSTEM...WITH THE BEST
DISPERSION RATES OCCURRING DURING THE STORM.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL MIDNIGHT MST TONIGHT WYZ003-019-020-022.

WINTER WEATHER ADVISORY UNTIL 6 AM MST SUNDAY WYZ016-026-027.

WINTER STORM WARNING UNTIL 6 AM MST SUNDAY
WYZ001-002-012>015-023>025.

HIGH WIND WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
WYZ010.

HIGH WIND WATCH FROM SUNDAY MORNING THROUGH SUNDAY AFTERNOON
WYZ016-017.

&&

$$

SHORT TERM...HATTINGS
LONG TERM...SKRBAC
AVIATION...C.BAKER
FIRE WEATHER...HATTINGS






000
FXUS65 KRIW 221723
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1023 AM MST SAT NOV 22 2014

.SHORT TERM...SATURDAY THROUGH MONDAY NIGHT

WITH THE DIFFERENCES IN THE WEATHER ACROSS THE AREA WE WILL DIVIDE
THE DISCUSSION INTO WEST OF THE DIVIDE AND EAST OF THE DIVIDE.

WEST OF THE DIVIDE...IT LOOKS LIKE AN ACTIVE 36 HOURS OR SO AS THE
NEXT WEATHER MAKER NOW OVER IDAHO IN THE FORM OF A COLD FRONT AND
ASSOCIATED TROUGH MAKES ITS WAY TOWARD THE AREA. RADAR OUT OF OUR
NEIGHBORS TO THE WEST SHOW SOME SNOW MOVING INTO THE WESTERN
MOUNTAINS AND THE WEB CAMS CONFIRM THIS. THERE STILL LOOK TO BE TWO
DIFFERENT PARTS TO THIS SYSTEM. THE FIRST WILL BE THE WARM ADVECTION
THAT FALLS THIS MORNING. THE SECOND WILL BE THEN PASSAGE OF THE COLD
FRONT. THE MODELS CONTINUE TO BE IN FAIRLY GOOD AGREEMENT IN
BRINGING THE HEAVIEST PRECIPITATION FROM AROUND MID MORNING TO
AROUND EARLY AFTERNOON ACROSS MUCH OF THE AREA WITH THE FRONTAL
PASSAGE AND BEST UPPER LEVEL SUPPORT. CONTINUITY HANDLED THIS FAIRLY
WELL SO WE MADE FEW CHANGES TO THIS. THERE IS ONE CONCERN WE HAVE
HOWEVER. UNLIKE THE LAST SYSTEMS...THIS ONE IS PACIFIC IN ORIGIN AND
DOES NOT HAVE REALLY COLD AIR WITH IT. THE MODELS ARE SHOWING SOME
WARMER AIR THAT MAY ADVECT INTO THE WEST PRIOR TO THE PASSAGE OF THE
COLD FRONT. THE NAM SHOWS 700 MILLIBAR TEMPERATURES RISING TO AROUND
MINUS 3 THAT WOULD RAISE SNOW LEVELS TO AROUND 7000 FEET EARLY IN
THE AFTERNOON. THAT COULD LEAD TO SOME MIXING THAT COULD HOLD DOWN
ACCUMULATIONS. THE GFS IS COOLER BY ABOUT 1 TO 2 DEGREES CELSIUS AND
THAT WOULD KEEP THE PRECIPITATION MAINLY SNOW. FOR NOW...WE ALLOWED
FOR SOME MIXING IN SOME SOUTHERN PORTIONS OF THE HIGHLIGHT AREA
EARLY IN THE AFTERNOON BEFORE THE FRONTAL PASSAGE.

THE HEAVIEST SNOW SHOULD END THIS EVENING AS THE FORCING MOVES AWAY.
HOWEVER...WITH A SOMEWHAT MOIST WEST TO NORTHWESTERLY FLOW
CONTINUING OCCASIONAL SNOW WILL CONTINUE INTO TONIGHT AND INTO
TOMORROW AS WELL. TEMPERATURES WILL BE COLDER BUT NOT NEARLY AS COLD
AS LAST WEEK. ACCUMULATION WILL CONTINUE ALTHOUGH AT THIS POINT
ADDITIONAL AMOUNTS LOOK TO BE FAIRLY LIGHT. ANOTHER SPOKE OF ENERGY
IN THE FORM OF A SHORTWAVE COULD BRING SOME ADDITIONAL STEADIER SNOW
SUNDAY NIGHT AS WELL. WITH THE NORTHWEST FLOW CONTINUING SNOW
SHOWERS LOOK CONTINUE TO BE A GOOD BET RIGHT INTO MONDAY. AS ALWAYS
WITH NORTHWEST FLOW...THERE COULD BE A HEAVIER BAND THAT SETS UP BUT
PINPOINTING THESE IS IMPOSSIBLE. SOMETHING TO WATCH THOUGH.
TEMPERATURES ARE EXPECTED TO BE FAIRLY CLOSE TO NORMAL.

EAST OF THE DIVIDE...THE MAIN CONCERN HERE SHIFTS FROM THE THE WHITE
STUFF TO WIND. AHEAD OF THE COLD FRONT...IT LOOKS QUITE WINDY IN THE
FAVORED AREAS WITH SOUTHWEST FLOW. THE MODELS CONTINUE TO SHOW 50 TO
60 KNOTS ALOFT AND WITH SOME MIXING WE SHOULD SEE SOME WIND GUSTS TO
OVER 60 MPH ACROSS NATRONA COUNTY AS WELL AS THE RATTLESNAKE RANGE
AND CODY FOOTHILLS...ESPECIALLY NEAR THE GREAT CROSSROAD OF CLARK.
WINDS HAVE ALREADY GUSTED OVER 60 MPH THERE. WE THOUGHT ABOUT
DROPPING THE WARNING FOR CASPER MOUNTAIN...BUT WILL LEAVE IT FOR
NOW. AS FOR CHANCES OF PRECIPITATION...THEY LOOK FAIRLY SPARSE
DURING THE DAY AS DOWN SLOPING FLOW KEEPS THINGS DRY FOR MOST AREAS
EXCEPT THE MOUNTAINS. WE KEPT A SLIGHT CHANCE FOR MANY AREAS BUT
INCREASED IT TOWARD EVENING. THE EXCEPTION WOULD BE A PLACE LIKE
DUBOIS WHERE SOME BLOW OVER MAY BRING SNOW. THIS WILL ALSO BRING THE
WARMEST TEMPERATURES MANY AREAS HAVE SEEN SINCE A WEEK AGO ON
SUNDAY. THE GFS MOS NUMBERS ARE ESPECIALLY WARM...WARMING SOME AREAS
INTO THE 50S. WE KEPT THINGS A BUT COOLER FOR NOW THINKING THAT IF
IT GETS WARMER THAN THE PREDICTED HIGH TEMPERATURES...MOST PEOPLE
WILL BE HAPPY. IT WILL COOL OFF TONIGHT AFTER THE FRONT PASSES.
THERE IS THE CHANCE FOR SOME SNOW BANDS WITH THE NORTHWEST FLOW BUT
AGAIN THESE ARE IMPOSSIBLE TO PINPOINT UNTIL THEY FORM. SOMETHING TO
WATCH THOUGH.

WIND IS ONCE AGAIN THE PROBLEM FOR SUNDAY. HOWEVER...THE AREAS OF
CONCERN SWITCH TO THE FAVORED AREAS WITH NORTHWEST FLOW. THAT MEANS
PORTIONS OF NORTHERN JOHNSON COUNTY AS WELL AS THE WIND RIVER BASIN.
AGAIN WITH 700 MILLIBAR WINDS AROUND 50 KNOTS AS A RESULT WE HOISTED A
HIGH WIND WATCH FOR THESE AREAS FOR SUNDAY AND WILL CONTINUE IT AT
THIS TIME. THERE WILL STILL BE NORTHWEST FLOW AND CYCLONIC CURVATURE
OVER THE AREA AS WELL. THAT MEANS THE CHANCE FOR SOME SHOWERS
ALTHOUGH MOST AREAS SHOULD BE DRY MOST OF THE TIME. THE EXCEPTION
WOULD BE THE BIGHORN MOUNTAINS WHERE A FEW INCHES OF SNOW ARE
POSSIBLE. MONDAY LOOKS TO BE A SIMILAR DAY WITH SCATTERED SNOW
SHOWERS. WINDS SHOULD BE NOT QUITE AS STRONG...ALTHOUGH STILL GUSTY
FOR MOST AREAS.

.LONG TERM...TUESDAY THROUGH SATURDAY

MEDIUM RANGE MODELS START OUT IN PRETTY GOOD AGREEMENT BUT THEN
DIVERGE SIGNIFICANTLY FROM THANKSGIVING ONWARD. TO START THE
PERIOD ON TUESDAY...WE GET IN A DECENT ISENTROPIC UP GLIDE NW FLOW
PATTERN THAT COULD BRING SOME DECENT SNOW THE THE WRN AND NRN
MOUNTAINS TUESDAY INTO TUESDAY NIGHT. LIKELY POPS COVER THIS
PERIOD IN MOST OF THE WEST AND IN THE BIGHORN MTNS WITH A CHANCE
ACROSS THE LOWER ELEVATIONS OF THE NORTH. AFTER THAT...THE CHANGES
START. THE FIRST BIG DIFFERENCE IS HOW THE GULF OF ALASKA UPPER
LOW IS HANDLED. THE GFS TAKES THIS SYSTEM INLAND AND THEN SLIDES
IT SEWD DOWN THE BACK SIDE OF OUR RIDGE ALONG THE COAST RESULTING
IN A DECENT CHANCE OF SNOW WEDNESDAY NIGHT AND THURSDAY ACROSS ALL
BUT THE SW PART OF THE AREA. THE ECMWF WEAKENS THIS GULF OF ALASKA
LOW AS IT MOVES INLAND AND RUNS INTO THE CONFLUENT FLOW BETWEEN
THE WEST COAST RIDGE AND THE NNW FLOW FROM AROUND THE HUDSON BAY
LOW. ECMWF ENSEMBLES ALSO SUPPORT THE OP ECMWF. THE GEM SHOWS A
MORE GLANCING BLOW THAN THE GFS WITH WHAT`S LEFT OF THE GULF OF
ALASKA UPPER LOW WITH MAINLY A DRY FRONT CLIPPING THE NERN ZONES
WEDNESDAY NIGHT AND THURSDAY. LEANING MORE TOWARDS THE ECMWF EVEN
THOUGH IT HAS STRUGGLED OVER THE PAST SEVERAL DAYS. END RESULT FOR
OUR AREA IS WARMER TEMPERATURES FOR THANKSGIVING THAN THE GFS
WOULD INDICATE AND LITTLE IF ANY PCPN. WE WILL STILL NEED TO WATCH
IT CLOSELY. KEEPING SOME 20-30 POPS ACROSS THE WEST AND NORTH
WEDNESDAY NIGHT AND THEN DECREASING ON THANKSGIVING. FLAT RIDGE
HOLDS THROUGH THE END OF THE PERIOD WITH A POSSIBLE WEAK SHORTWAVE
MOVING IN ON SATURDAY FOR A CHANCE OF MTN SNOW IN THE WEST.
SHORTWAVE MOVING SOUTH TOWARDS THE NRN HIGH PLAINS MAY ALSO PUSH A
FRONT INTO THE NERN ZONES FRIDAY NIGHT AND SATURDAY.

.AVIATION.../18Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES

AREAS OF LLWS WILL CONTINUE OVER THE CENTRAL BASINS AS WEST WINDS
FL070-100 BETWEEN 45-50KTS. THESE STRONGER WINDS WILL MIX DOWN TO
THE SURFACE FROM VCNTY 50NE SM KRKS-KCPR AND FROM VCNTY KCOD- KDUB
WHERE HIGH WIND WARNINGS ARE IN EFFECT. A STRONG COLD FRONT WILL
PUSH ACROSS THE AREA EARLY THIS EVENING. MTNS WILL BE MOSTLY
OBSCURED ALONG THE DIVIDE AHEAD OF THE FRONT WITH SOME BLOW OVER
PCPN IN THE VCNTY OF KLND-KCOD.  A BAND OF SNOW WILL LIKELY
ACCOMPANY THE FRONT THIS EVENING ALONG WITH AREAS OF MVFR/IFR -SN MAINLY
VCNTY ALONG AND EAST OF THE BIGHORN RANGE AND INTERSTATE 25. AREAS
OF SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL FOLLOW THE
FRONT...DECREASING AFTER 06Z SUNDAY.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES

MVFR/IFR CEILINGS AND VISIBILITIES REDUCED IN SNOW...BLOWING SNOW
AND FOG WILL CONTINUE ACROSS THE WEST THROUGH 18Z SUNDAY.  LLWS
WILL ALSO PERSIST ACROSS THE AREA AS FL070-100 WINDS INCREASE TO
BTWN 40-50KTS. A STRONG COLD FRONT WILL PUSH ACROSS THE AREA
THIS AFTERNOON...AREAS OF WEST SFC WIND 20-30KTS WITH GUSTS TO
40KTS.

.FIRE WEATHER...

A WINTER WEATHER SYSTEM WILL IMPACT WESTERN WYOMING THROUGH TODAY.
ADDITIONALLY...STRONG WIND WILL OCCUR ACROSS THE WIND CORRIDOR
BETWEEN ROCK SPRINGS AND CASPER...AND WILL ALSO DEVELOP IN THE
CODY FOOTHILLS. HIGH WIND WARNINGS ARE IN EFFECT FOR MUCH OF THE
DAY TODAY FOR THESE LOCATIONS. FIRE WEATHER BEHAVIOR IS
EXPECTED TO REMAIN MINIMAL UNDER THIS SYSTEM...WITH THE BEST
DISPERSION RATES OCCURRING DURING THE STORM.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL MIDNIGHT MST TONIGHT WYZ003-019-020-022.

WINTER WEATHER ADVISORY UNTIL 6 AM MST SUNDAY WYZ016-026-027.

WINTER STORM WARNING UNTIL 6 AM MST SUNDAY
WYZ001-002-012>015-023>025.

HIGH WIND WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
WYZ010.

HIGH WIND WATCH FROM SUNDAY MORNING THROUGH SUNDAY AFTERNOON
WYZ016-017.

&&

$$

SHORT TERM...HATTINGS
LONG TERM...SKRBAC
AVIATION...C.BAKER
FIRE WEATHER...HATTINGS







000
FXUS63 KUNR 221538
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
838 AM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 835 AM MST SAT NOV 22 2014

POTENT NW CONUS UPPER TROUGH CONTINUES TO ADVECT EAST INTO THE
NORTHERN PLAINS. TIMING OF UVM LOOKS OT BE A LITTLE EARLIER THAN
PREVIOUS GUIDANCE SUGGESTED. GIVEN UPSTREAM OB TRENDS...WENT AHEAD
AND INCREASED POPS THIS AFTERNOON FAR NW. OTHERWISE...WENT AHEAD
AND ISSUED A HIGH WIND WATCH FOR NW SD SUNDAY GIVEN
MOMENTUM/MIXING PROGS. WIND GUSTS TO AROUND 60 LOOK LIKELY ACROSS
FAR NW SD...AND POSSIBLE AS FAR SOUTH AS RAPID CITY.

&&

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
ISSUED AT 301 AM MST SAT NOV 22 2014

AN ACTIVE WESTERLY FLOW ALOFT DOMINATES THE LARGE
SCALE FOR THE NORTHERN U.S. THIS MORNING.  WEAK IMPULSES EMBEDDED IN
THE FLOW ARE MOVING INTO THE NORTHERN PLAINS PRODUCING SOME VERY
LIGHT PRECIPITATION EAST OF THE CONTDVD...BUT NO SIGNIFICANT FRONTAL
BOUNDARIES ARE IN THE ANALYSIS ACROSS THE NORTHERN PLAINS OR
NORTHERN ROCKIES. EARLY MORNING TEMPERATURES ACROSS THE NORTHERN
PLAINS ARE SEASONABLY MILD BUT WARM CONSIDERABLY TO THE WEST IN THE
NORTHERN INTERMOUNTAIN REGION. A VIGOROUS FAST MOVING PACIFIC SHORT
WAVE WAS MOVING ONSHORE AT 09Z. A SPLIT FLOW OVER THE SOUTHERN GREAT
BASIN HAS PRETTY MUCH CUT OFF THE HIGH AMPLITUDE TROUGH OVER THE
SOUTHWESTERN U.S. AND NORTHERN MEXICO WHICH IS MAKING SLOW PROGRESS
EASTWARD.

TODAY...ANOTHER DAY OF ABOVE NORMAL TEMPERATURES IS IN STORE FOR
NORTHEAST WYOMING AND WESTERN SOUTH DAKOTA TODAY.  THE APPROACHING
WEATHER SYSTEM WILL PRODUCE INCREASING HIGH CLOUDS FROM MID MORNING
ONWARD...BUT MAXIMUM TEMPERATURES ARE STILL EXPECTED TO BE AT LEAST
A COUPLE DEGREES HIGHER THAN YESTERDAY.  A FEW LIGHT RAIN SHOWERS
ARE POSSIBLE OVER NORTHEAST WYOMING AND THE BLKHLS REGION LATE THIS
AFTERNOON WITH THE DCVA FROM THE APPROACHING SYSTEM.

TONIGHT...THE MAIN PRECIPITATION EVENT WILL BEGIN DURING THE LATE
EVENING HOURS AS THE FAST MOVING COLD FRONT MOVES INTO THE PLAINS.
THE PRECIP WILL FALL AS RAIN INITIALLY THEN BECOME MIXED WITH SNOW
AFTER 06Z AND BE ALL SNOW BY EARLY SUNDAY MORNING.  DEPENDING ON
WHEN THE SWITCHOVER ACTUALLY OCCURS THE HIGHER ELEVATIONS OF THE
BLKHLS AND NORTHEAST WYOMING COULD SEE FROM 4 TO 8 INCHES OF NEW
SNOW BY EARLY SUNDAY.

SUNDAY...THE PACIFIC TROUGH IS FORECAST TO BEGIN SPLITTING AND
SLOWING DOWN AS IT MOVES INTO THE PLAINS EARLY SUNDAY.  THIS
EVOLUTION WILL CREATE A PERIOD OF STRONG NORTHERLY SURFACE FLOW
...ESPECIALLY ACROSS WESTERN SOUTH DAKOTA...BY MIDDAY SUNDAY. THE
WINDS AND COLDER TEMPERATURES WILL BECOME THE MAIN WEATHER STORY ON
SUNDAY AS DYNAMICS TO SUPPORT THE LIGHT SNOW WILL GRADUALLY FADE.
WIND SPEEDS MEETING HIGH WIND CRITERIA ARE A POSSIBILITY EARLY
SUNDAY AFTERNOON.

SUNDAY NIGHT...LIGHT SNOW SHOWERS WILL CONTINUE THROUGH THE
OVERNIGHT HOURS BEHIND THE MAIN WEATHER SYSTEM WITH LITTLE
ACCUMULATION. MID LEVEL COLD ADVECTION AND A FEW WEAK EMBEDDED
IMPULSES WILL CONTINUE ALL NIGHT.

&&

.LONG TERM...MONDAY THROUGH FRIDAY
ISSUED AT 301 AM MST SAT NOV 22 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. SEVERAL WEAK DISTURBANCES WITHIN THE NORTHWEST FLOW WILL
BRING CLOUDS AND CHANCES FOR SNOW AT TIMES THROUGH TUESDAY. A COLD
FRONT WILL CROSS THE DAKOTAS WEDNESDAY...BRINGING COOLER TEMPS
ACROSS MOST AREAS. SNOW IS ALSO EXPECTED TO DEVELOP ALONG THE
BAROCLINIC ZONE...ESPECIALLY ACROSS NE WY AND PORTIONS OF FAR WRN
SD.

THERE IS STILL UNCERTAINTY TOWARD THE LATTER PART OF NEXT
WEEK...WITH LONGER RANGE MODELS CONTINUING TO FIGURE OUT WHAT TYPE
OF AIRMASS WILL BE OVER THE AREA. MODELS HAVE BEEN SHOWING WARMER
AIR ADVECTING IN WITH THE FRONTAL BOUNDARY SLIDING EAST OF THE
CWA...BUT THE 00Z GFS HAS TRENDED BACK TO A COLDER SOLUTION WHILE
THE 00Z ECM HAS TRENDED WARMER. WILL STICK WITH TEMPS IN THE MIDDLE
OF ALL SOLUTIONS.

&&

.AVIATION...FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING
ISSUED AT 301 AM MST SAT NOV 22 2014

VFR CONDITIONS EXPECTED THROUGH THIS AFTERNOON. BREEZY
SOUTHWEST WILL CONTINUE ACROSS NORTHEAST WY/HIGHER ELEVATIONS OF THE
BLACK HILLS TODAY. A COLD FRONT WILL CROSS THE AREA TONIGHT...WITH
GUSTY NW WINDS DEVELOPING BEHIND THE FRONT. CHANCES FOR SHRA ARE
EXPECTED THIS AFTN AND TONIGHT...CHANGING TO SHSN OVERNIGHT.


&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...HIGH WIND WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR
     SDZ001-002-012-013-025-026-031-072-073.

WY...NONE.
&&

$$

UPDATE...JC
SHORT TERM...CARPENTER
LONG TERM...13
AVIATION...13






000
FXUS63 KUNR 221538
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
838 AM MST SAT NOV 22 2014

.UPDATE...
ISSUED AT 835 AM MST SAT NOV 22 2014

POTENT NW CONUS UPPER TROUGH CONTINUES TO ADVECT EAST INTO THE
NORTHERN PLAINS. TIMING OF UVM LOOKS OT BE A LITTLE EARLIER THAN
PREVIOUS GUIDANCE SUGGESTED. GIVEN UPSTREAM OB TRENDS...WENT AHEAD
AND INCREASED POPS THIS AFTERNOON FAR NW. OTHERWISE...WENT AHEAD
AND ISSUED A HIGH WIND WATCH FOR NW SD SUNDAY GIVEN
MOMENTUM/MIXING PROGS. WIND GUSTS TO AROUND 60 LOOK LIKELY ACROSS
FAR NW SD...AND POSSIBLE AS FAR SOUTH AS RAPID CITY.

&&

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
ISSUED AT 301 AM MST SAT NOV 22 2014

AN ACTIVE WESTERLY FLOW ALOFT DOMINATES THE LARGE
SCALE FOR THE NORTHERN U.S. THIS MORNING.  WEAK IMPULSES EMBEDDED IN
THE FLOW ARE MOVING INTO THE NORTHERN PLAINS PRODUCING SOME VERY
LIGHT PRECIPITATION EAST OF THE CONTDVD...BUT NO SIGNIFICANT FRONTAL
BOUNDARIES ARE IN THE ANALYSIS ACROSS THE NORTHERN PLAINS OR
NORTHERN ROCKIES. EARLY MORNING TEMPERATURES ACROSS THE NORTHERN
PLAINS ARE SEASONABLY MILD BUT WARM CONSIDERABLY TO THE WEST IN THE
NORTHERN INTERMOUNTAIN REGION. A VIGOROUS FAST MOVING PACIFIC SHORT
WAVE WAS MOVING ONSHORE AT 09Z. A SPLIT FLOW OVER THE SOUTHERN GREAT
BASIN HAS PRETTY MUCH CUT OFF THE HIGH AMPLITUDE TROUGH OVER THE
SOUTHWESTERN U.S. AND NORTHERN MEXICO WHICH IS MAKING SLOW PROGRESS
EASTWARD.

TODAY...ANOTHER DAY OF ABOVE NORMAL TEMPERATURES IS IN STORE FOR
NORTHEAST WYOMING AND WESTERN SOUTH DAKOTA TODAY.  THE APPROACHING
WEATHER SYSTEM WILL PRODUCE INCREASING HIGH CLOUDS FROM MID MORNING
ONWARD...BUT MAXIMUM TEMPERATURES ARE STILL EXPECTED TO BE AT LEAST
A COUPLE DEGREES HIGHER THAN YESTERDAY.  A FEW LIGHT RAIN SHOWERS
ARE POSSIBLE OVER NORTHEAST WYOMING AND THE BLKHLS REGION LATE THIS
AFTERNOON WITH THE DCVA FROM THE APPROACHING SYSTEM.

TONIGHT...THE MAIN PRECIPITATION EVENT WILL BEGIN DURING THE LATE
EVENING HOURS AS THE FAST MOVING COLD FRONT MOVES INTO THE PLAINS.
THE PRECIP WILL FALL AS RAIN INITIALLY THEN BECOME MIXED WITH SNOW
AFTER 06Z AND BE ALL SNOW BY EARLY SUNDAY MORNING.  DEPENDING ON
WHEN THE SWITCHOVER ACTUALLY OCCURS THE HIGHER ELEVATIONS OF THE
BLKHLS AND NORTHEAST WYOMING COULD SEE FROM 4 TO 8 INCHES OF NEW
SNOW BY EARLY SUNDAY.

SUNDAY...THE PACIFIC TROUGH IS FORECAST TO BEGIN SPLITTING AND
SLOWING DOWN AS IT MOVES INTO THE PLAINS EARLY SUNDAY.  THIS
EVOLUTION WILL CREATE A PERIOD OF STRONG NORTHERLY SURFACE FLOW
...ESPECIALLY ACROSS WESTERN SOUTH DAKOTA...BY MIDDAY SUNDAY. THE
WINDS AND COLDER TEMPERATURES WILL BECOME THE MAIN WEATHER STORY ON
SUNDAY AS DYNAMICS TO SUPPORT THE LIGHT SNOW WILL GRADUALLY FADE.
WIND SPEEDS MEETING HIGH WIND CRITERIA ARE A POSSIBILITY EARLY
SUNDAY AFTERNOON.

SUNDAY NIGHT...LIGHT SNOW SHOWERS WILL CONTINUE THROUGH THE
OVERNIGHT HOURS BEHIND THE MAIN WEATHER SYSTEM WITH LITTLE
ACCUMULATION. MID LEVEL COLD ADVECTION AND A FEW WEAK EMBEDDED
IMPULSES WILL CONTINUE ALL NIGHT.

&&

.LONG TERM...MONDAY THROUGH FRIDAY
ISSUED AT 301 AM MST SAT NOV 22 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. SEVERAL WEAK DISTURBANCES WITHIN THE NORTHWEST FLOW WILL
BRING CLOUDS AND CHANCES FOR SNOW AT TIMES THROUGH TUESDAY. A COLD
FRONT WILL CROSS THE DAKOTAS WEDNESDAY...BRINGING COOLER TEMPS
ACROSS MOST AREAS. SNOW IS ALSO EXPECTED TO DEVELOP ALONG THE
BAROCLINIC ZONE...ESPECIALLY ACROSS NE WY AND PORTIONS OF FAR WRN
SD.

THERE IS STILL UNCERTAINTY TOWARD THE LATTER PART OF NEXT
WEEK...WITH LONGER RANGE MODELS CONTINUING TO FIGURE OUT WHAT TYPE
OF AIRMASS WILL BE OVER THE AREA. MODELS HAVE BEEN SHOWING WARMER
AIR ADVECTING IN WITH THE FRONTAL BOUNDARY SLIDING EAST OF THE
CWA...BUT THE 00Z GFS HAS TRENDED BACK TO A COLDER SOLUTION WHILE
THE 00Z ECM HAS TRENDED WARMER. WILL STICK WITH TEMPS IN THE MIDDLE
OF ALL SOLUTIONS.

&&

.AVIATION...FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING
ISSUED AT 301 AM MST SAT NOV 22 2014

VFR CONDITIONS EXPECTED THROUGH THIS AFTERNOON. BREEZY
SOUTHWEST WILL CONTINUE ACROSS NORTHEAST WY/HIGHER ELEVATIONS OF THE
BLACK HILLS TODAY. A COLD FRONT WILL CROSS THE AREA TONIGHT...WITH
GUSTY NW WINDS DEVELOPING BEHIND THE FRONT. CHANCES FOR SHRA ARE
EXPECTED THIS AFTN AND TONIGHT...CHANGING TO SHSN OVERNIGHT.


&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...HIGH WIND WATCH FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR
     SDZ001-002-012-013-025-026-031-072-073.

WY...NONE.
&&

$$

UPDATE...JC
SHORT TERM...CARPENTER
LONG TERM...13
AVIATION...13







000
FXUS65 KCYS 221218
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
518 AM MST SAT NOV 22 2014

.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 342 AM MST SAT NOV 22 2014

TODAY...INHERITED WIND AND SNOW HIGHLITES LOOK ON TRACK. FOR
WIND...ARLINGTON ALREADY SEEING SUSTAINED 45 MPH WITH GUSTS IN THE
MID 50S. WINDS EXPECTED TO CONTINUE TO RAMP UP AS 850/700 MB CRAIG
TO CASPER HEIGHT GRADIENTS RISE TO NEAR 70 METERS BY LATE AFTERNOON.
BASED ON LOW AND MID LEVEL HEIGHT GRADIENTS...INHERITED HIGH WIND
WARNING ON TRACK...AND WILL UPGRADE THE HIGH WIND WATCH TO A WARNING
FOR LATE MORNING AND LATER TODAY FOR CHEYENNE...PLATTE AND CONVERSE
COUNTIES AS AGREE WITH DAY SHIFT REASONING FROM YESTERDAY. PROGGED
SURFACE THROUGH 700 MB GRADIENTS LOOK FAVORABLE. OROGRAPHIC SNOWS
EXPECTED TO CRANK UP LATE THIS AFTERNOON OVER THE SNOWY AND SIERRA
MADRE RANGES AS A PACIFIC COLD FRONT ENTERS THE REGION. FORECAST QPF
AND OROGRAPHICS SUGGEST AN UPGRADE TO A WINTER STORM WARNING THERE.

TONIGHT...STRONG BORA WINDS CONTINUE IN THE POST COLD FRONTAL
AIRMASS AND THUS THE CONTINUATION OF THE HIGH WIND WARNING. HEIGHT
GRADIENTS DECREASE THUS SLOWLY DECREASING WINDS. MODERATE TO HEAVY
SNOW WILL CONTINUE OVER THE SNOWY AND SIERRA MADRE RANGES IN MOIST
OROGRAPHIC FLOW.

SUNDAY...BLUSTERY AND WINDY DAY IN THE WAKE OF THE COLD FRONT WITH
OROGRAPHIC SNOWS IN EARNEST CONTINUING OVER THE SOUTHWEST MOUNTAINS.

SUNDAY NIGHT...CONTINUED BREEZY TO WINDY PER PROGGED SURFACE THROUGH
700 MB GRADIENTS...THOUGH NOT AS WINDY AS SATURDAY NIGHT. COLD AND
BLUSTERY WITH OROGRAPHIC SNOWS CONTINUING IN MOIST FLOW OVER THE
SNOWY AND SIERRA MADRE RANGES.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 342 AM MST SAT NOV 22 2014

ONGOING SNOW EVENT OVR THE SNOWY AND SIERRA MADRE RANGES WILL KICK
OFF THE PERIOD AS TRAILING SHORTWAVE TROUGH IN NORTHWEST FLOW CLIPS
THE AREA. MOUNTAINS LOCATIONS WILL SEE AN ADDITIONAL 3 TO 6 INCHES
ON MONDAY. THESE RATES WILL CONTINUE TO WARRANT THE AFOREMENTIONED
WINTER STORM WARNING OVR THE MOUNTAINS. POST-FRONTAL NORTHWEST FLOW
WILL NOT BE ALL THAT FAVORABLE FOR PRECIP OUTSIDE OF OROGRAPHIC
AREAS...HOWEVER MAY SEE NW/SE ORIENTED SNOW BANDS SET UP...
ESPECIALLY DURING THE AFTERNOON HOURS. POST FRONTAL LLVL CAA WILL
YIELD HIGHS MONDAY ONLY IN THE 20S WEST OF THE LARAMIE RANGE...WITH
30S ON THE ERN PLAINS. IT WILL FEEL MUCH COLDER HOWEVER...WITH
NORTHWEST WINDS GUSTING TO 35-45 MPH AT TIMES. DEPENDING UPON THE
AMOUNT OF CLEARING/MIXING...AREAS IN THE PANHANDLE MAY NEED A WIND
ADVISORY IN TIME.

NW FLOW WILL CONTINUE ON TUESDAY. OROGRAPHICALLY FAVORED AREAS WILL
STILL SEE LT SNOW...HOWEVER RATES SHOULD NO LONGER NECESSITATE A
WINTER HIGHLIGHT. ANY SNOW CHANCES WILL AGAIN STRUGGLE TO PULL AWAY
FROM THE MTNS...ESPECIALLY DURING THE DAYTIME HOURS. THE ECMWF DOES
HINT THAT SNOW CHANCES WILL SPILL OUT ONTO THE PLAINS TUESDAY NIGHT.
THE GFS IS LESS AGGRESSIVE WITH THIS IDEA HOWEVER...CONFINING
CHANCES TO THE MOUNTAINS TUESDAY NIGHT. ANOTHER DAY OF BREEZY WEST
WINDS ACROSS THE CWFA TUESDAY WITH GUSTS AGAIN 30-40 MPH.

MEDIUM RANGE MODELS CONTINUE TO STRUGGLE WED-SAT...WITH THE MILLION
DOLLAR QUESTION CENTERING AROUND THE POSSIBILITY OF AN ARCTIC
BOUNDARY BCMNG STATIONARY WED NIGHT AND THU. MODELS ARE NOTORIOUS
FOR STRUGGLING IN THE DEPTH OF COLD AIR MASS THIS FAR OUT. THE 00Z
ECMWF IS MUCH MORE AMPLIFIED WITH A BUILDING RIDGE ALONG THE WEST
COAST...WHILE THE GFS IS SIGNIFICANTLY FLATTER. SO DESPITE SOME
SOLUTION CONGRUENCY IN YESTERDAYS 12Z MODEL SUITES...DIFFERENCES
REAR THEIR UGLY HEAD ONCE AGAIN IN 00Z DATA. FOR NOW...HAVE KEPT
THINGS RELATIVELY DRY AND MILD...FAVORING THE MORE CONSISTENT ECMWF.
HOWEVER...IF TRENDS TURN TOWARDS THE GFS COULD SEE A PERIOD OF SNOW
WED NT/THU ALONG WITH A COOLER THANKSGIVING DAY. STAY TUNED.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 512 AM MST SAT NOV 22 2014

AVIATION CONCERNS CENTER AROUND STRONG WINDS AT MOST SITES.
SOUTHWEST WINDS WILL GUST TO BETWEEN 35 AND 50 KNOTS AT
KRWL...KLAR AND KCYS. SITES IN THE WRN NEBRASKA PANHANDLE WILL
SEE SLIGHTLY LIGHTER WINDS...BUT STILL BREEZY WITH GUSTS 25-35
KNOTS LIKELY. WINDS WILL DECREASE SOMEWHAT AROUND 02Z. THE OTHER
CONCERN WILL BE DETERIORATING CONDITIONS AT KRWL AFTER 21Z AND
KLAR AFTER 07Z. KRWL MAY SEE A -RA/-SN MIX INITIALLY BUT TURN OVER
COMPLETELY TO SNOW BY 00Z. MAY ALSO SEE A PERIOD OF LIGHT SNOW
SHOWERS OVR THE WRN NEBRASKA PANHANDLE SITES AFTER 00Z...BUT
CONFIDENCE IS LESS WHETHER OR NOT COVERAGE WILL BE ENOUGH TO CARRY
MUCH IMPACT AT THOSE TERMINALS. SE WY MOUNTAINS WILL BE OBSCURED
THIS AFTERNOON AND TONIGHT.

&&

.FIRE WEATHER...
ISSUED AT 342 AM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG TODAY AND TONIGHT...MINIMAL FIRE
WEATHER CONCERNS DUE TO COOL TEMPERATURES AND HIGHER HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO 5 PM MST MONDAY
     FOR WYZ112-114.

     HIGH WIND WARNING UNTIL 5 AM MST SUNDAY FOR WYZ103>106-110-116-
     117.

     HIGH WIND WARNING FROM 11 AM THIS MORNING TO 5 AM MST SUNDAY FOR
     WYZ101-107-115-118.

NE...NONE.
&&

$$

SHORT TERM...RUBIN
LONG TERM...CAH
AVIATION...CAH
FIRE WEATHER...RUBIN




000
FXUS65 KCYS 221050
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
350 AM MST SAT NOV 22 2014

.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 342 AM MST SAT NOV 22 2014

TODAY...INHERITED WIND AND SNOW HIGHLITES LOOK ON TRACK. FOR
WIND...ARLINGTON ALREADY SEEING SUSTAINED 45 MPH WITH GUSTS IN THE
MID 50S. WINDS EXPECTED TO CONTINUE TO RAMP UP AS 850/700 MB CRAIG
TO CASPER HEIGHT GRADIENTS RISE TO NEAR 70 METERS BY LATE AFTERNOON.
BASED ON LOW AND MID LEVEL HEIGHT GRADIENTS...INHERITED HIGH WIND
WARNING ON TRACK...AND WILL UPGRADE THE HIGH WIND WATCH TO A WARNING
FOR LATE MORNING AND LATER TODAY FOR CHEYENNE...PLATTE AND CONVERSE
COUNTIES AS AGREE WITH DAY SHIFT REASONING FROM YESTERDAY. PROGGED
SURFACE THROUGH 700 MB GRADIENTS LOOK FAVORABLE. OROGRAPHIC SNOWS
EXPECTED TO CRANK UP LATE THIS AFTERNOON OVER THE SNOWY AND SIERRA
MADRE RANGES AS A PACIFIC COLD FRONT ENTERS THE REGION. FORECAST QPF
AND OROGRAPHICS SUGGEST AN UPGRADE TO A WINTER STORM WARNING THERE.

TONIGHT...STRONG BORA WINDS CONTINUE IN THE POST COLD FRONTAL
AIRMASS AND THUS THE CONTINUATION OF THE HIGH WIND WARNING. HEIGHT
GRADIENTS DECREASE THUS SLOWLY DECREASING WINDS. MODERATE TO HEAVY
SNOW WILL CONTINUE OVER THE SNOWY AND SIERRA MADRE RANGES IN MOIST
OROGRAPHIC FLOW.

SUNDAY...BLUSTERY AND WINDY DAY IN THE WAKE OF THE COLD FRONT WITH
OROGRAPHIC SNOWS IN EARNEST CONTINUING OVER THE SOUTHWEST MOUNTAINS.

SUNDAY NIGHT...CONTINUED BREEZY TO WINDY PER PROGGED SURFACE THROUGH
700 MB GRADIENTS...THOUGH NOT AS WINDY AS SATURDAY NIGHT. COLD AND
BLUSTERY WITH OROGRAPHIC SNOWS CONTINUING IN MOIST FLOW OVER THE
SNOWY AND SIERRA MADRE RANGES.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 342 AM MST SAT NOV 22 2014

ONGOING SNOW EVENT OVR THE SNOWY AND SIERRA MADRE RANGES WILL KICK
OFF THE PERIOD AS TRAILING SHORTWAVE TROUGH IN NORTHWEST FLOW CLIPS
THE AREA. MOUNTAINS LOCATIONS WILL SEE AN ADDITIONAL 3 TO 6 INCHES
ON MONDAY. THESE RATES WILL CONTINUE TO WARRANT THE AFOREMENTIONED
WINTER STORM WARNING OVR THE MOUNTAINS. POST-FRONTAL NORTHWEST FLOW
WILL NOT BE ALL THAT FAVORABLE FOR PRECIP OUTSIDE OF OROGRAPHIC
AREAS...HOWEVER MAY SEE NW/SE ORIENTED SNOW BANDS SET UP...
ESPECIALLY DURING THE AFTERNOON HOURS. POST FRONTAL LLVL CAA WILL
YIELD HIGHS MONDAY ONLY IN THE 20S WEST OF THE LARAMIE RANGE...WITH
30S ON THE ERN PLAINS. IT WILL FEEL MUCH COLDER HOWEVER...WITH
NORTHWEST WINDS GUSTING TO 35-45 MPH AT TIMES. DEPENDING UPON THE
AMOUNT OF CLEARING/MIXING...AREAS IN THE PANHANDLE MAY NEED A WIND
ADVISORY IN TIME.

NW FLOW WILL CONTINUE ON TUESDAY. OROGRAPHICALLY FAVORED AREAS WILL
STILL SEE LT SNOW...HOWEVER RATES SHOULD NO LONGER NECESSITATE A
WINTER HIGHLIGHT. ANY SNOW CHANCES WILL AGAIN STRUGGLE TO PULL AWAY
FROM THE MTNS...ESPECIALLY DURING THE DAYTIME HOURS. THE ECMWF DOES
HINT THAT SNOW CHANCES WILL SPILL OUT ONTO THE PLAINS TUESDAY NIGHT.
THE GFS IS LESS AGGRESSIVE WITH THIS IDEA HOWEVER...CONFINING
CHANCES TO THE MOUNTAINS TUESDAY NIGHT. ANOTHER DAY OF BREEZY WEST
WINDS ACROSS THE CWFA TUESDAY WITH GUSTS AGAIN 30-40 MPH.

MEDIUM RANGE MODELS CONTINUE TO STRUGGLE WED-SAT...WITH THE MILLION
DOLLAR QUESTION CENTERING AROUND THE POSSIBILITY OF AN ARCTIC
BOUNDARY BCMNG STATIONARY WED NIGHT AND THU. MODELS ARE NOTORIOUS
FOR STRUGGLING IN THE DEPTH OF COLD AIR MASS THIS FAR OUT. THE 00Z
ECMWF IS MUCH MORE AMPLIFIED WITH A BUILDING RIDGE ALONG THE WEST
COAST...WHILE THE GFS IS SIGNIFICANTLY FLATTER. SO DESPITE SOME
SOLUTION CONGRUENCY IN YESTERDAYS 12Z MODEL SUITES...DIFFERENCES
REAR THEIR UGLY HEAD ONCE AGAIN IN 00Z DATA. FOR NOW...HAVE KEPT
THINGS RELATIVELY DRY AND MILD...FAVORING THE MORE CONSISTENT ECMWF.
HOWEVER...IF TRENDS TURN TOWARDS THE GFS COULD SEE A PERIOD OF SNOW
WED NT/THU ALONG WITH A COOLER THANKSGIVING DAY. STAY TUNED.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1000 PM MST FRI NOV 21 2014

PRIMARY AVIATION CONCERNS WILL FOCUS ON STRONG WINDS OVERNIGHT
TONIGHT THROUGH SATURDAY NIGHT...WITH ACCUMULATING SNOW DEVELOPING
OVER THE MOUNTAINS SATURDAY AFTERNOON. FREQUENT GUSTS TO 50 KT AND
HIGHER WILL DEVELOP IN THE ARLINGTON AND BORDEAUX AREAS BETWEEN
09Z AND 12Z TONIGHT. THESE STRONG WEST TO SOUTHWEST WINDS WILL
THEN SPREAD INTO THE SOUTHERN AND NORTHERN LARAMIE RANGES SATURDAY
MORNING. GUSTY WINDS WILL ALSO SPREAD INTO LOWER ELEVATIONS AND
INTO THE PLAINS OF SOUTHEAST WYOMING SATURDAY AFTERNOON WITH GUSTS
OF 30 TO 40 KT COMMON. WINDS WILL NOT BE AS STRONG ACROSS THE
WESTERN NEBRASKA PANHANDLE BUT STILL BREEZY. THE MOUNTAINS WILL BE
OBSCURED DUE TO FALLING AND BLOWING SNOW SATURDAY AFTERNOON AND
EVENING. PREVAILING MVFR CEILINGS/VISIBIITIES WERE INTRODUCED AT
RAWLINS BEGINNING LATE SATURDAY AFTERNOON WITH DEVELOPING LIGHT
RAIN/SNOW.

&&

.FIRE WEATHER...
ISSUED AT 342 AM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG TODAY AND TONIGHT...MINIMAL FIRE
WEATHER CONCERNS DUE TO COOL TEMPERATURES AND HIGHER HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO 5 PM MST MONDAY
     FOR WYZ112-114.

     HIGH WIND WARNING UNTIL 5 AM MST SUNDAY FOR WYZ103>106-110-116-
     117.

     HIGH WIND WARNING FROM 11 AM THIS MORNING TO 5 AM MST SUNDAY FOR
     WYZ101-107-115-118.

NE...NONE.

&&

$$

SHORT TERM...RUBIN
LONG TERM...CAH
AVIATION...MAJ
FIRE WEATHER...RUBIN



000
FXUS65 KCYS 221050
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
350 AM MST SAT NOV 22 2014

.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 342 AM MST SAT NOV 22 2014

TODAY...INHERITED WIND AND SNOW HIGHLITES LOOK ON TRACK. FOR
WIND...ARLINGTON ALREADY SEEING SUSTAINED 45 MPH WITH GUSTS IN THE
MID 50S. WINDS EXPECTED TO CONTINUE TO RAMP UP AS 850/700 MB CRAIG
TO CASPER HEIGHT GRADIENTS RISE TO NEAR 70 METERS BY LATE AFTERNOON.
BASED ON LOW AND MID LEVEL HEIGHT GRADIENTS...INHERITED HIGH WIND
WARNING ON TRACK...AND WILL UPGRADE THE HIGH WIND WATCH TO A WARNING
FOR LATE MORNING AND LATER TODAY FOR CHEYENNE...PLATTE AND CONVERSE
COUNTIES AS AGREE WITH DAY SHIFT REASONING FROM YESTERDAY. PROGGED
SURFACE THROUGH 700 MB GRADIENTS LOOK FAVORABLE. OROGRAPHIC SNOWS
EXPECTED TO CRANK UP LATE THIS AFTERNOON OVER THE SNOWY AND SIERRA
MADRE RANGES AS A PACIFIC COLD FRONT ENTERS THE REGION. FORECAST QPF
AND OROGRAPHICS SUGGEST AN UPGRADE TO A WINTER STORM WARNING THERE.

TONIGHT...STRONG BORA WINDS CONTINUE IN THE POST COLD FRONTAL
AIRMASS AND THUS THE CONTINUATION OF THE HIGH WIND WARNING. HEIGHT
GRADIENTS DECREASE THUS SLOWLY DECREASING WINDS. MODERATE TO HEAVY
SNOW WILL CONTINUE OVER THE SNOWY AND SIERRA MADRE RANGES IN MOIST
OROGRAPHIC FLOW.

SUNDAY...BLUSTERY AND WINDY DAY IN THE WAKE OF THE COLD FRONT WITH
OROGRAPHIC SNOWS IN EARNEST CONTINUING OVER THE SOUTHWEST MOUNTAINS.

SUNDAY NIGHT...CONTINUED BREEZY TO WINDY PER PROGGED SURFACE THROUGH
700 MB GRADIENTS...THOUGH NOT AS WINDY AS SATURDAY NIGHT. COLD AND
BLUSTERY WITH OROGRAPHIC SNOWS CONTINUING IN MOIST FLOW OVER THE
SNOWY AND SIERRA MADRE RANGES.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 342 AM MST SAT NOV 22 2014

ONGOING SNOW EVENT OVR THE SNOWY AND SIERRA MADRE RANGES WILL KICK
OFF THE PERIOD AS TRAILING SHORTWAVE TROUGH IN NORTHWEST FLOW CLIPS
THE AREA. MOUNTAINS LOCATIONS WILL SEE AN ADDITIONAL 3 TO 6 INCHES
ON MONDAY. THESE RATES WILL CONTINUE TO WARRANT THE AFOREMENTIONED
WINTER STORM WARNING OVR THE MOUNTAINS. POST-FRONTAL NORTHWEST FLOW
WILL NOT BE ALL THAT FAVORABLE FOR PRECIP OUTSIDE OF OROGRAPHIC
AREAS...HOWEVER MAY SEE NW/SE ORIENTED SNOW BANDS SET UP...
ESPECIALLY DURING THE AFTERNOON HOURS. POST FRONTAL LLVL CAA WILL
YIELD HIGHS MONDAY ONLY IN THE 20S WEST OF THE LARAMIE RANGE...WITH
30S ON THE ERN PLAINS. IT WILL FEEL MUCH COLDER HOWEVER...WITH
NORTHWEST WINDS GUSTING TO 35-45 MPH AT TIMES. DEPENDING UPON THE
AMOUNT OF CLEARING/MIXING...AREAS IN THE PANHANDLE MAY NEED A WIND
ADVISORY IN TIME.

NW FLOW WILL CONTINUE ON TUESDAY. OROGRAPHICALLY FAVORED AREAS WILL
STILL SEE LT SNOW...HOWEVER RATES SHOULD NO LONGER NECESSITATE A
WINTER HIGHLIGHT. ANY SNOW CHANCES WILL AGAIN STRUGGLE TO PULL AWAY
FROM THE MTNS...ESPECIALLY DURING THE DAYTIME HOURS. THE ECMWF DOES
HINT THAT SNOW CHANCES WILL SPILL OUT ONTO THE PLAINS TUESDAY NIGHT.
THE GFS IS LESS AGGRESSIVE WITH THIS IDEA HOWEVER...CONFINING
CHANCES TO THE MOUNTAINS TUESDAY NIGHT. ANOTHER DAY OF BREEZY WEST
WINDS ACROSS THE CWFA TUESDAY WITH GUSTS AGAIN 30-40 MPH.

MEDIUM RANGE MODELS CONTINUE TO STRUGGLE WED-SAT...WITH THE MILLION
DOLLAR QUESTION CENTERING AROUND THE POSSIBILITY OF AN ARCTIC
BOUNDARY BCMNG STATIONARY WED NIGHT AND THU. MODELS ARE NOTORIOUS
FOR STRUGGLING IN THE DEPTH OF COLD AIR MASS THIS FAR OUT. THE 00Z
ECMWF IS MUCH MORE AMPLIFIED WITH A BUILDING RIDGE ALONG THE WEST
COAST...WHILE THE GFS IS SIGNIFICANTLY FLATTER. SO DESPITE SOME
SOLUTION CONGRUENCY IN YESTERDAYS 12Z MODEL SUITES...DIFFERENCES
REAR THEIR UGLY HEAD ONCE AGAIN IN 00Z DATA. FOR NOW...HAVE KEPT
THINGS RELATIVELY DRY AND MILD...FAVORING THE MORE CONSISTENT ECMWF.
HOWEVER...IF TRENDS TURN TOWARDS THE GFS COULD SEE A PERIOD OF SNOW
WED NT/THU ALONG WITH A COOLER THANKSGIVING DAY. STAY TUNED.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1000 PM MST FRI NOV 21 2014

PRIMARY AVIATION CONCERNS WILL FOCUS ON STRONG WINDS OVERNIGHT
TONIGHT THROUGH SATURDAY NIGHT...WITH ACCUMULATING SNOW DEVELOPING
OVER THE MOUNTAINS SATURDAY AFTERNOON. FREQUENT GUSTS TO 50 KT AND
HIGHER WILL DEVELOP IN THE ARLINGTON AND BORDEAUX AREAS BETWEEN
09Z AND 12Z TONIGHT. THESE STRONG WEST TO SOUTHWEST WINDS WILL
THEN SPREAD INTO THE SOUTHERN AND NORTHERN LARAMIE RANGES SATURDAY
MORNING. GUSTY WINDS WILL ALSO SPREAD INTO LOWER ELEVATIONS AND
INTO THE PLAINS OF SOUTHEAST WYOMING SATURDAY AFTERNOON WITH GUSTS
OF 30 TO 40 KT COMMON. WINDS WILL NOT BE AS STRONG ACROSS THE
WESTERN NEBRASKA PANHANDLE BUT STILL BREEZY. THE MOUNTAINS WILL BE
OBSCURED DUE TO FALLING AND BLOWING SNOW SATURDAY AFTERNOON AND
EVENING. PREVAILING MVFR CEILINGS/VISIBIITIES WERE INTRODUCED AT
RAWLINS BEGINNING LATE SATURDAY AFTERNOON WITH DEVELOPING LIGHT
RAIN/SNOW.

&&

.FIRE WEATHER...
ISSUED AT 342 AM MST SAT NOV 22 2014

ALTHOUGH WINDS WILL BE STRONG TODAY AND TONIGHT...MINIMAL FIRE
WEATHER CONCERNS DUE TO COOL TEMPERATURES AND HIGHER HUMIDITIES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO 5 PM MST MONDAY
     FOR WYZ112-114.

     HIGH WIND WARNING UNTIL 5 AM MST SUNDAY FOR WYZ103>106-110-116-
     117.

     HIGH WIND WARNING FROM 11 AM THIS MORNING TO 5 AM MST SUNDAY FOR
     WYZ101-107-115-118.

NE...NONE.

&&

$$

SHORT TERM...RUBIN
LONG TERM...CAH
AVIATION...MAJ
FIRE WEATHER...RUBIN




000
FXUS63 KUNR 221002
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
302 AM MST SAT NOV 22 2014

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
ISSUED AT 301 AM MST SAT NOV 22 2014

AN ACTIVE WESTERLY FLOW ALOFT DOMINATES THE LARGE
SCALE FOR THE NORTHERN U.S. THIS MORNING.  WEAK IMPULSES EMBEDDED IN
THE FLOW ARE MOVING INTO THE NORTHERN PLAINS PRODUCING SOME VERY
LIGHT PRECIPITATION EAST OF THE CONTDVD...BUT NO SIGNIFICANT FRONTAL
BOUNDARIES ARE IN THE ANALYSIS ACROSS THE NORTHERN PLAINS OR
NORTHERN ROCKIES. EARLY MORNING TEMPERATURES ACROSS THE NORTHERN
PLAINS ARE SEASONABLY MILD BUT WARM CONSIDERABLY TO THE WEST IN THE
NORTHERN INTERMOUNTAIN REGION. A VIGOROUS FAST MOVING PACIFIC SHORT
WAVE WAS MOVING ONSHORE AT 09Z. A SPLIT FLOW OVER THE SOUTHERN GREAT
BASIN HAS PRETTY MUCH CUT OFF THE HIGH AMPLITUDE TROUGH OVER THE
SOUTHWESTERN U.S. AND NORTHERN MEXICO WHICH IS MAKING SLOW PROGRESS
EASTWARD.

TODAY...ANOTHER DAY OF ABOVE NORMAL TEMPERATURES IS IN STORE FOR
NORTHEAST WYOMING AND WESTERN SOUTH DAKOTA TODAY.  THE APPROACHING
WEATHER SYSTEM WILL PRODUCE INCREASING HIGH CLOUDS FROM MID MORNING
ONWARD...BUT MAXIMUM TEMPERATURES ARE STILL EXPECTED TO BE AT LEAST
A COUPLE DEGREES HIGHER THAN YESTERDAY.  A FEW LIGHT RAIN SHOWERS
ARE POSSIBLE OVER NORTHEAST WYOMING AND THE BLKHLS REGION LATE THIS
AFTERNOON WITH THE DCVA FROM THE APPROACHING SYSTEM.

TONIGHT...THE MAIN PRECIPITATION EVENT WILL BEGIN DURING THE LATE
EVENING HOURS AS THE FAST MOVING COLD FRONT MOVES INTO THE PLAINS.
THE PRECIP WILL FALL AS RAIN INITIALLY THEN BECOME MIXED WITH SNOW
AFTER 06Z AND BE ALL SNOW BY EARLY SUNDAY MORNING.  DEPENDING ON
WHEN THE SWITCHOVER ACTUALLY OCCURS THE HIGHER ELEVATIONS OF THE
BLKHLS AND NORTHEAST WYOMING COULD SEE FROM 4 TO 8 INCHES OF NEW
SNOW BY EARLY SUNDAY.

SUNDAY...THE PACIFIC TROUGH IS FORECAST TO BEGIN SPLITTING AND
SLOWING DOWN AS IT MOVES INTO THE PLAINS EARLY SUNDAY.  THIS
EVOLUTION WILL CREATE A PERIOD OF STRONG NORTHERLY SURFACE FLOW
...ESPECIALLY ACROSS WESTERN SOUTH DAKOTA...BY MIDDAY SUNDAY. THE
WINDS AND COLDER TEMPERATURES WILL BECOME THE MAIN WEATHER STORY ON
SUNDAY AS DYNAMICS TO SUPPORT THE LIGHT SNOW WILL GRADUALLY FADE.
WIND SPEEDS MEETING HIGH WIND CRITERIA ARE A POSSIBILITY EARLY
SUNDAY AFTERNOON.

SUNDAY NIGHT...LIGHT SNOW SHOWERS WILL CONTINUE THROUGH THE
OVERNIGHT HOURS BEHIND THE MAIN WEATHER SYSTEM WITH LITTLE
ACCUMULATION. MID LEVEL COLD ADVECTION AND A FEW WEAK EMBEDDED
IMPULSES WILL CONTINUE ALL NIGHT.
&&

.LONG TERM...MONDAY THROUGH FRIDAY
ISSUED AT 301 AM MST SAT NOV 22 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. SEVERAL WEAK DISTURBANCES WITHIN THE NORTHWEST FLOW WILL
BRING CLOUDS AND CHANCES FOR SNOW AT TIMES THROUGH TUESDAY. A COLD
FRONT WILL CROSS THE DAKOTAS WEDNESDAY...BRINGING COOLER TEMPS
ACROSS MOST AREAS. SNOW IS ALSO EXPECTED TO DEVELOP ALONG THE
BAROCLINIC ZONE...ESPECIALLY ACROSS NE WY AND PORTIONS OF FAR WRN
SD.

THERE IS STILL UNCERTAINTY TOWARD THE LATTER PART OF NEXT
WEEK...WITH LONGER RANGE MODELS CONTINUING TO FIGURE OUT WHAT TYPE
OF AIRMASS WILL BE OVER THE AREA. MODELS HAVE BEEN SHOWING WARMER
AIR ADVECTING IN WITH THE FRONTAL BOUNDARY SLIDING EAST OF THE
CWA...BUT THE 00Z GFS HAS TRENDED BACK TO A COLDER SOLUTION WHILE
THE 00Z ECM HAS TRENDED WARMER. WILL STICK WITH TEMPS IN THE MIDDLE
OF ALL SOLUTIONS.

&&

.AVIATION...FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING
ISSUED AT 301 AM MST SAT NOV 22 2014

VFR CONDITIONS EXPECTED THROUGH THIS AFTERNOON. BREEZY
SOUTHWEST WILL CONTINUE ACROSS NORTHEAST WY/HIGHER ELEVATIONS OF THE
BLACK HILLS TODAY. A COLD FRONT WILL CROSS THE AREA TONIGHT...WITH
GUSTY NW WINDS DEVELOPING BEHIND THE FRONT. CHANCES FOR SHRA ARE
EXPECTED THIS AFTN AND TONIGHT...CHANGING TO SHSN OVERNIGHT.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...CARPENTER
LONG TERM...13
AVIATION...13






000
FXUS63 KUNR 221002
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
302 AM MST SAT NOV 22 2014

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
ISSUED AT 301 AM MST SAT NOV 22 2014

AN ACTIVE WESTERLY FLOW ALOFT DOMINATES THE LARGE
SCALE FOR THE NORTHERN U.S. THIS MORNING.  WEAK IMPULSES EMBEDDED IN
THE FLOW ARE MOVING INTO THE NORTHERN PLAINS PRODUCING SOME VERY
LIGHT PRECIPITATION EAST OF THE CONTDVD...BUT NO SIGNIFICANT FRONTAL
BOUNDARIES ARE IN THE ANALYSIS ACROSS THE NORTHERN PLAINS OR
NORTHERN ROCKIES. EARLY MORNING TEMPERATURES ACROSS THE NORTHERN
PLAINS ARE SEASONABLY MILD BUT WARM CONSIDERABLY TO THE WEST IN THE
NORTHERN INTERMOUNTAIN REGION. A VIGOROUS FAST MOVING PACIFIC SHORT
WAVE WAS MOVING ONSHORE AT 09Z. A SPLIT FLOW OVER THE SOUTHERN GREAT
BASIN HAS PRETTY MUCH CUT OFF THE HIGH AMPLITUDE TROUGH OVER THE
SOUTHWESTERN U.S. AND NORTHERN MEXICO WHICH IS MAKING SLOW PROGRESS
EASTWARD.

TODAY...ANOTHER DAY OF ABOVE NORMAL TEMPERATURES IS IN STORE FOR
NORTHEAST WYOMING AND WESTERN SOUTH DAKOTA TODAY.  THE APPROACHING
WEATHER SYSTEM WILL PRODUCE INCREASING HIGH CLOUDS FROM MID MORNING
ONWARD...BUT MAXIMUM TEMPERATURES ARE STILL EXPECTED TO BE AT LEAST
A COUPLE DEGREES HIGHER THAN YESTERDAY.  A FEW LIGHT RAIN SHOWERS
ARE POSSIBLE OVER NORTHEAST WYOMING AND THE BLKHLS REGION LATE THIS
AFTERNOON WITH THE DCVA FROM THE APPROACHING SYSTEM.

TONIGHT...THE MAIN PRECIPITATION EVENT WILL BEGIN DURING THE LATE
EVENING HOURS AS THE FAST MOVING COLD FRONT MOVES INTO THE PLAINS.
THE PRECIP WILL FALL AS RAIN INITIALLY THEN BECOME MIXED WITH SNOW
AFTER 06Z AND BE ALL SNOW BY EARLY SUNDAY MORNING.  DEPENDING ON
WHEN THE SWITCHOVER ACTUALLY OCCURS THE HIGHER ELEVATIONS OF THE
BLKHLS AND NORTHEAST WYOMING COULD SEE FROM 4 TO 8 INCHES OF NEW
SNOW BY EARLY SUNDAY.

SUNDAY...THE PACIFIC TROUGH IS FORECAST TO BEGIN SPLITTING AND
SLOWING DOWN AS IT MOVES INTO THE PLAINS EARLY SUNDAY.  THIS
EVOLUTION WILL CREATE A PERIOD OF STRONG NORTHERLY SURFACE FLOW
...ESPECIALLY ACROSS WESTERN SOUTH DAKOTA...BY MIDDAY SUNDAY. THE
WINDS AND COLDER TEMPERATURES WILL BECOME THE MAIN WEATHER STORY ON
SUNDAY AS DYNAMICS TO SUPPORT THE LIGHT SNOW WILL GRADUALLY FADE.
WIND SPEEDS MEETING HIGH WIND CRITERIA ARE A POSSIBILITY EARLY
SUNDAY AFTERNOON.

SUNDAY NIGHT...LIGHT SNOW SHOWERS WILL CONTINUE THROUGH THE
OVERNIGHT HOURS BEHIND THE MAIN WEATHER SYSTEM WITH LITTLE
ACCUMULATION. MID LEVEL COLD ADVECTION AND A FEW WEAK EMBEDDED
IMPULSES WILL CONTINUE ALL NIGHT.
&&

.LONG TERM...MONDAY THROUGH FRIDAY
ISSUED AT 301 AM MST SAT NOV 22 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. SEVERAL WEAK DISTURBANCES WITHIN THE NORTHWEST FLOW WILL
BRING CLOUDS AND CHANCES FOR SNOW AT TIMES THROUGH TUESDAY. A COLD
FRONT WILL CROSS THE DAKOTAS WEDNESDAY...BRINGING COOLER TEMPS
ACROSS MOST AREAS. SNOW IS ALSO EXPECTED TO DEVELOP ALONG THE
BAROCLINIC ZONE...ESPECIALLY ACROSS NE WY AND PORTIONS OF FAR WRN
SD.

THERE IS STILL UNCERTAINTY TOWARD THE LATTER PART OF NEXT
WEEK...WITH LONGER RANGE MODELS CONTINUING TO FIGURE OUT WHAT TYPE
OF AIRMASS WILL BE OVER THE AREA. MODELS HAVE BEEN SHOWING WARMER
AIR ADVECTING IN WITH THE FRONTAL BOUNDARY SLIDING EAST OF THE
CWA...BUT THE 00Z GFS HAS TRENDED BACK TO A COLDER SOLUTION WHILE
THE 00Z ECM HAS TRENDED WARMER. WILL STICK WITH TEMPS IN THE MIDDLE
OF ALL SOLUTIONS.

&&

.AVIATION...FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING
ISSUED AT 301 AM MST SAT NOV 22 2014

VFR CONDITIONS EXPECTED THROUGH THIS AFTERNOON. BREEZY
SOUTHWEST WILL CONTINUE ACROSS NORTHEAST WY/HIGHER ELEVATIONS OF THE
BLACK HILLS TODAY. A COLD FRONT WILL CROSS THE AREA TONIGHT...WITH
GUSTY NW WINDS DEVELOPING BEHIND THE FRONT. CHANCES FOR SHRA ARE
EXPECTED THIS AFTN AND TONIGHT...CHANGING TO SHSN OVERNIGHT.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...CARPENTER
LONG TERM...13
AVIATION...13







000
FXUS63 KUNR 221002
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
302 AM MST SAT NOV 22 2014

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
ISSUED AT 301 AM MST SAT NOV 22 2014

AN ACTIVE WESTERLY FLOW ALOFT DOMINATES THE LARGE
SCALE FOR THE NORTHERN U.S. THIS MORNING.  WEAK IMPULSES EMBEDDED IN
THE FLOW ARE MOVING INTO THE NORTHERN PLAINS PRODUCING SOME VERY
LIGHT PRECIPITATION EAST OF THE CONTDVD...BUT NO SIGNIFICANT FRONTAL
BOUNDARIES ARE IN THE ANALYSIS ACROSS THE NORTHERN PLAINS OR
NORTHERN ROCKIES. EARLY MORNING TEMPERATURES ACROSS THE NORTHERN
PLAINS ARE SEASONABLY MILD BUT WARM CONSIDERABLY TO THE WEST IN THE
NORTHERN INTERMOUNTAIN REGION. A VIGOROUS FAST MOVING PACIFIC SHORT
WAVE WAS MOVING ONSHORE AT 09Z. A SPLIT FLOW OVER THE SOUTHERN GREAT
BASIN HAS PRETTY MUCH CUT OFF THE HIGH AMPLITUDE TROUGH OVER THE
SOUTHWESTERN U.S. AND NORTHERN MEXICO WHICH IS MAKING SLOW PROGRESS
EASTWARD.

TODAY...ANOTHER DAY OF ABOVE NORMAL TEMPERATURES IS IN STORE FOR
NORTHEAST WYOMING AND WESTERN SOUTH DAKOTA TODAY.  THE APPROACHING
WEATHER SYSTEM WILL PRODUCE INCREASING HIGH CLOUDS FROM MID MORNING
ONWARD...BUT MAXIMUM TEMPERATURES ARE STILL EXPECTED TO BE AT LEAST
A COUPLE DEGREES HIGHER THAN YESTERDAY.  A FEW LIGHT RAIN SHOWERS
ARE POSSIBLE OVER NORTHEAST WYOMING AND THE BLKHLS REGION LATE THIS
AFTERNOON WITH THE DCVA FROM THE APPROACHING SYSTEM.

TONIGHT...THE MAIN PRECIPITATION EVENT WILL BEGIN DURING THE LATE
EVENING HOURS AS THE FAST MOVING COLD FRONT MOVES INTO THE PLAINS.
THE PRECIP WILL FALL AS RAIN INITIALLY THEN BECOME MIXED WITH SNOW
AFTER 06Z AND BE ALL SNOW BY EARLY SUNDAY MORNING.  DEPENDING ON
WHEN THE SWITCHOVER ACTUALLY OCCURS THE HIGHER ELEVATIONS OF THE
BLKHLS AND NORTHEAST WYOMING COULD SEE FROM 4 TO 8 INCHES OF NEW
SNOW BY EARLY SUNDAY.

SUNDAY...THE PACIFIC TROUGH IS FORECAST TO BEGIN SPLITTING AND
SLOWING DOWN AS IT MOVES INTO THE PLAINS EARLY SUNDAY.  THIS
EVOLUTION WILL CREATE A PERIOD OF STRONG NORTHERLY SURFACE FLOW
...ESPECIALLY ACROSS WESTERN SOUTH DAKOTA...BY MIDDAY SUNDAY. THE
WINDS AND COLDER TEMPERATURES WILL BECOME THE MAIN WEATHER STORY ON
SUNDAY AS DYNAMICS TO SUPPORT THE LIGHT SNOW WILL GRADUALLY FADE.
WIND SPEEDS MEETING HIGH WIND CRITERIA ARE A POSSIBILITY EARLY
SUNDAY AFTERNOON.

SUNDAY NIGHT...LIGHT SNOW SHOWERS WILL CONTINUE THROUGH THE
OVERNIGHT HOURS BEHIND THE MAIN WEATHER SYSTEM WITH LITTLE
ACCUMULATION. MID LEVEL COLD ADVECTION AND A FEW WEAK EMBEDDED
IMPULSES WILL CONTINUE ALL NIGHT.
&&

.LONG TERM...MONDAY THROUGH FRIDAY
ISSUED AT 301 AM MST SAT NOV 22 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. SEVERAL WEAK DISTURBANCES WITHIN THE NORTHWEST FLOW WILL
BRING CLOUDS AND CHANCES FOR SNOW AT TIMES THROUGH TUESDAY. A COLD
FRONT WILL CROSS THE DAKOTAS WEDNESDAY...BRINGING COOLER TEMPS
ACROSS MOST AREAS. SNOW IS ALSO EXPECTED TO DEVELOP ALONG THE
BAROCLINIC ZONE...ESPECIALLY ACROSS NE WY AND PORTIONS OF FAR WRN
SD.

THERE IS STILL UNCERTAINTY TOWARD THE LATTER PART OF NEXT
WEEK...WITH LONGER RANGE MODELS CONTINUING TO FIGURE OUT WHAT TYPE
OF AIRMASS WILL BE OVER THE AREA. MODELS HAVE BEEN SHOWING WARMER
AIR ADVECTING IN WITH THE FRONTAL BOUNDARY SLIDING EAST OF THE
CWA...BUT THE 00Z GFS HAS TRENDED BACK TO A COLDER SOLUTION WHILE
THE 00Z ECM HAS TRENDED WARMER. WILL STICK WITH TEMPS IN THE MIDDLE
OF ALL SOLUTIONS.

&&

.AVIATION...FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING
ISSUED AT 301 AM MST SAT NOV 22 2014

VFR CONDITIONS EXPECTED THROUGH THIS AFTERNOON. BREEZY
SOUTHWEST WILL CONTINUE ACROSS NORTHEAST WY/HIGHER ELEVATIONS OF THE
BLACK HILLS TODAY. A COLD FRONT WILL CROSS THE AREA TONIGHT...WITH
GUSTY NW WINDS DEVELOPING BEHIND THE FRONT. CHANCES FOR SHRA ARE
EXPECTED THIS AFTN AND TONIGHT...CHANGING TO SHSN OVERNIGHT.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...CARPENTER
LONG TERM...13
AVIATION...13







000
FXUS63 KUNR 221002
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
302 AM MST SAT NOV 22 2014

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
ISSUED AT 301 AM MST SAT NOV 22 2014

AN ACTIVE WESTERLY FLOW ALOFT DOMINATES THE LARGE
SCALE FOR THE NORTHERN U.S. THIS MORNING.  WEAK IMPULSES EMBEDDED IN
THE FLOW ARE MOVING INTO THE NORTHERN PLAINS PRODUCING SOME VERY
LIGHT PRECIPITATION EAST OF THE CONTDVD...BUT NO SIGNIFICANT FRONTAL
BOUNDARIES ARE IN THE ANALYSIS ACROSS THE NORTHERN PLAINS OR
NORTHERN ROCKIES. EARLY MORNING TEMPERATURES ACROSS THE NORTHERN
PLAINS ARE SEASONABLY MILD BUT WARM CONSIDERABLY TO THE WEST IN THE
NORTHERN INTERMOUNTAIN REGION. A VIGOROUS FAST MOVING PACIFIC SHORT
WAVE WAS MOVING ONSHORE AT 09Z. A SPLIT FLOW OVER THE SOUTHERN GREAT
BASIN HAS PRETTY MUCH CUT OFF THE HIGH AMPLITUDE TROUGH OVER THE
SOUTHWESTERN U.S. AND NORTHERN MEXICO WHICH IS MAKING SLOW PROGRESS
EASTWARD.

TODAY...ANOTHER DAY OF ABOVE NORMAL TEMPERATURES IS IN STORE FOR
NORTHEAST WYOMING AND WESTERN SOUTH DAKOTA TODAY.  THE APPROACHING
WEATHER SYSTEM WILL PRODUCE INCREASING HIGH CLOUDS FROM MID MORNING
ONWARD...BUT MAXIMUM TEMPERATURES ARE STILL EXPECTED TO BE AT LEAST
A COUPLE DEGREES HIGHER THAN YESTERDAY.  A FEW LIGHT RAIN SHOWERS
ARE POSSIBLE OVER NORTHEAST WYOMING AND THE BLKHLS REGION LATE THIS
AFTERNOON WITH THE DCVA FROM THE APPROACHING SYSTEM.

TONIGHT...THE MAIN PRECIPITATION EVENT WILL BEGIN DURING THE LATE
EVENING HOURS AS THE FAST MOVING COLD FRONT MOVES INTO THE PLAINS.
THE PRECIP WILL FALL AS RAIN INITIALLY THEN BECOME MIXED WITH SNOW
AFTER 06Z AND BE ALL SNOW BY EARLY SUNDAY MORNING.  DEPENDING ON
WHEN THE SWITCHOVER ACTUALLY OCCURS THE HIGHER ELEVATIONS OF THE
BLKHLS AND NORTHEAST WYOMING COULD SEE FROM 4 TO 8 INCHES OF NEW
SNOW BY EARLY SUNDAY.

SUNDAY...THE PACIFIC TROUGH IS FORECAST TO BEGIN SPLITTING AND
SLOWING DOWN AS IT MOVES INTO THE PLAINS EARLY SUNDAY.  THIS
EVOLUTION WILL CREATE A PERIOD OF STRONG NORTHERLY SURFACE FLOW
...ESPECIALLY ACROSS WESTERN SOUTH DAKOTA...BY MIDDAY SUNDAY. THE
WINDS AND COLDER TEMPERATURES WILL BECOME THE MAIN WEATHER STORY ON
SUNDAY AS DYNAMICS TO SUPPORT THE LIGHT SNOW WILL GRADUALLY FADE.
WIND SPEEDS MEETING HIGH WIND CRITERIA ARE A POSSIBILITY EARLY
SUNDAY AFTERNOON.

SUNDAY NIGHT...LIGHT SNOW SHOWERS WILL CONTINUE THROUGH THE
OVERNIGHT HOURS BEHIND THE MAIN WEATHER SYSTEM WITH LITTLE
ACCUMULATION. MID LEVEL COLD ADVECTION AND A FEW WEAK EMBEDDED
IMPULSES WILL CONTINUE ALL NIGHT.
&&

.LONG TERM...MONDAY THROUGH FRIDAY
ISSUED AT 301 AM MST SAT NOV 22 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. SEVERAL WEAK DISTURBANCES WITHIN THE NORTHWEST FLOW WILL
BRING CLOUDS AND CHANCES FOR SNOW AT TIMES THROUGH TUESDAY. A COLD
FRONT WILL CROSS THE DAKOTAS WEDNESDAY...BRINGING COOLER TEMPS
ACROSS MOST AREAS. SNOW IS ALSO EXPECTED TO DEVELOP ALONG THE
BAROCLINIC ZONE...ESPECIALLY ACROSS NE WY AND PORTIONS OF FAR WRN
SD.

THERE IS STILL UNCERTAINTY TOWARD THE LATTER PART OF NEXT
WEEK...WITH LONGER RANGE MODELS CONTINUING TO FIGURE OUT WHAT TYPE
OF AIRMASS WILL BE OVER THE AREA. MODELS HAVE BEEN SHOWING WARMER
AIR ADVECTING IN WITH THE FRONTAL BOUNDARY SLIDING EAST OF THE
CWA...BUT THE 00Z GFS HAS TRENDED BACK TO A COLDER SOLUTION WHILE
THE 00Z ECM HAS TRENDED WARMER. WILL STICK WITH TEMPS IN THE MIDDLE
OF ALL SOLUTIONS.

&&

.AVIATION...FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING
ISSUED AT 301 AM MST SAT NOV 22 2014

VFR CONDITIONS EXPECTED THROUGH THIS AFTERNOON. BREEZY
SOUTHWEST WILL CONTINUE ACROSS NORTHEAST WY/HIGHER ELEVATIONS OF THE
BLACK HILLS TODAY. A COLD FRONT WILL CROSS THE AREA TONIGHT...WITH
GUSTY NW WINDS DEVELOPING BEHIND THE FRONT. CHANCES FOR SHRA ARE
EXPECTED THIS AFTN AND TONIGHT...CHANGING TO SHSN OVERNIGHT.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...CARPENTER
LONG TERM...13
AVIATION...13






000
FXUS65 KRIW 220939
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
239 AM MST SAT NOV 22 2014

.SHORT TERM...SATURDAY THROUGH MONDAY NIGHT

WITH THE DIFFERENCES IN THE WEATHER ACROSS THE AREA WE WILL DIVIDE
THE DISCUSSION INTO WEST OF THE DIVIDE AND EAST OF THE DIVIDE.

WEST OF THE DIVIDE...IT LOOKS LIKE AN ACTIVE 36 HOURS OR SO AS THE
NEXT WEATHER MAKER NOW OVER IDAHO IN THE FORM OF A COLD FRONT AND
ASSOCIATED TROUGH MAKES ITS WAY TOWARD THE AREA. RADAR OUT OF OUR
NEIGHBORS TO THE WEST SHOW SOME SNOW MOVING INTO THE WESTERN
MOUNTAINS AND THE WEB CAMS CONFIRM THIS. THERE STILL LOOK TO BE TWO
DIFFERENT PARTS TO THIS SYSTEM. THE FIRST WILL BE THE WARM ADVECTION
THAT FALLS THIS MORNING. THE SECOND WILL BE THEN PASSAGE OF THE COLD
FRONT. THE MODELS CONTINUE TO BE IN FAIRLY GOOD AGREEMENT IN
BRINGING THE HEAVIEST PRECIPITATION FROM AROUND MID MORNING TO
AROUND EARLY AFTERNOON ACROSS MUCH OF THE AREA WITH THE FRONTAL
PASSAGE AND BEST UPPER LEVEL SUPPORT. CONTINUITY HANDLED THIS FAIRLY
WELL SO WE MADE FEW CHANGES TO THIS. THERE IS ONE CONCERN WE HAVE
HOWEVER. UNLIKE THE LAST SYSTEMS...THIS ONE IS PACIFIC IN ORIGIN AND
DOES NOT HAVE REALLY COLD AIR WITH IT. THE MODELS ARE SHOWING SOME
WARMER AIR THAT MAY ADVECT INTO THE WEST PRIOR TO THE PASSAGE OF THE
COLD FRONT. THE NAM SHOWS 700 MILLIBAR TEMPERATURES RISING TO AROUND
MINUS 3 THAT WOULD RAISE SNOW LEVELS TO AROUND 7000 FEET EARLY IN
THE AFTERNOON. THAT COULD LEAD TO SOME MIXING THAT COULD HOLD DOWN
ACCUMULATIONS. THE GFS IS COOLER BY ABOUT 1 TO 2 DEGREES CELSIUS AND
THAT WOULD KEEP THE PRECIPITATION MAINLY SNOW. FOR NOW...WE ALLOWED
FOR SOME MIXING IN SOME SOUTHERN PORTIONS OF THE HIGHLIGHT AREA
EARLY IN THE AFTERNOON BEFORE THE FRONTAL PASSAGE.

THE HEAVIEST SNOW SHOULD END THIS EVENING AS THE FORCING MOVES AWAY.
HOWEVER...WITH A SOMEWHAT MOIST WEST TO NORTHWESTERLY FLOW
CONTINUING OCCASIONAL SNOW WILL CONTINUE INTO TONIGHT AND INTO
TOMORROW AS WELL. TEMPERATURES WILL BE COLDER BUT NOT NEARLY AS COLD
AS LAST WEEK. ACCUMULATION WILL CONTINUE ALTHOUGH AT THIS POINT
ADDITIONAL AMOUNTS LOOK TO BE FAIRLY LIGHT. ANOTHER SPOKE OF ENERGY
IN THE FORM OF A SHORTWAVE COULD BRING SOME ADDITIONAL STEADIER SNOW
SUNDAY NIGHT AS WELL. WITH THE NORTHWEST FLOW CONTINUING SNOW
SHOWERS LOOK CONTINUE TO BE A GOOD BET RIGHT INTO MONDAY. AS ALWAYS
WITH NORTHWEST FLOW...THERE COULD BE A HEAVIER BAND THAT SETS UP BUT
PINPOINTING THESE IS IMPOSSIBLE. SOMETHING TO WATCH THOUGH.
TEMPERATURES ARE EXPECTED TO BE FAIRLY CLOSE TO NORMAL.

EAST OF THE DIVIDE...THE MAIN CONCERN HERE SHIFTS FROM THE THE WHITE
STUFF TO WIND. AHEAD OF THE COLD FRONT...IT LOOKS QUITE WINDY IN THE
FAVORED AREAS WITH SOUTHWEST FLOW. THE MODELS CONTINUE TO SHOW 50 TO
60 KNOTS ALOFT AND WITH SOME MIXING WE SHOULD SEE SOME WIND GUSTS TO
OVER 60 MPH ACROSS NATRONA COUNTY AS WELL AS THE RATTLESNAKE RANGE
AND CODY FOOTHILLS...ESPECIALLY NEAR THE GREAT CROSSROAD OF CLARK.
WINDS HAVE ALREADY GUSTED OVER 60 MPH THERE. WE THOUGHT ABOUT
DROPPING THE WARNING FOR CASPER MOUNTAIN...BUT WILL LEAVE IT FOR
NOW. AS FOR CHANCES OF PRECIPITATION...THEY LOOK FAIRLY SPARSE
DURING THE DAY AS DOWNSLOPING FLOW KEEPS THINGS DRY FOR MOST AREAS
EXCEPT THE MOUNTAINS. WE KEPT A SLIGHT CHANCE FOR MANY AREAS BUT
INCREASED IT TOWARD EVENING. THE EXCEPTION WOULD BE A PLACE LIKE
DUBOIS WHERE SOME BLOW OVER MAY BRING SNOW. THIS WILL ALSO BRING THE
WARMEST TEMPERATURES MANY AREAS HAVE SEEN SINCE A WEEK AGO ON
SUNDAY. THE GFS MOS NUMBERS ARE ESPECIALLY WARM...WARMING SOME AREAS
INTO THE 50S. WE KEPT THINGS A BUT COOLER FOR NOW THINKING THAT IF
IT GETS WARMER THAN THE PREDICTED HIGH TEMPERATURES...MOST PEOPLE
WILL BE HAPPY. IT WILL COOL OFF TONIGHT AFTER THE FRONT PASSES.
THERE IS THE CHANCE FOR SOME SNOW BANDS WITH THE NORTHWEST FLOW BUT
AGAIN THESE ARE IMPOSSIBLE TO PINPOINT UNTIL THEY FORM. SOMETHING TO
WATCH THOUGH.

WIND IS ONCE AGAIN THE PROBLEM FOR SUNDAY. HOWEVER...THE AREAS OF
CONCERN SWITCH TO THE FAVORED AREAS WITH NORTHWEST FLOW. THAT MEANS
PORTIONS OF NORTHERN JOHNSON COUNTY AS WELL AS THE WIND RIVER BASIN.
AGAIN WITH 700 MILLIBAR WINDS AROUND 50 KNOTS AS A RESULT WE HOISTED A
HIGH WIND WATCH FOR THESE AREAS FOR SUNDAY AND WILL CONTINUE IT AT
THIS TIME. THERE WILL STILL BE NORTHWEST FLOW AND CYCLONIC CURVATURE
OVER THE AREA AS WELL. THAT MEANS THE CHANCE FOR SOME SHOWERS
ALTHOUGH MOST AREAS SHOULD BE DRY MOST OF THE TIME. THE EXCEPTION
WOULD BE THE BIGHORN MOUNTAINS WHERE A FEW INCHES OF SNOW ARE
POSSIBLE. MONDAY LOOKS TO BE A SIMILAR DAY WITH SCATTERED SNOW
SHOWERS. WINDS SHOULD BE NOT QUITE AS STRONG...ALTHOUGH STILL GUSTY
FOR MOST AREAS.


.LONG TERM...TUESDAY THROUGH SATURDAY

MEDIUM RANGE MODELS START OUT IN PRETTY GOOD AGREEMENT BUT THEN
DIVERGE SIGNIFICANTLY FROM THANKSGIVING ONWARD. TO START THE
PERIOD ON TUESDAY...WE GET IN A DECENT ISENTROPIC UPGLIDE NW FLOW
PATTERN THAT COULD BRING SOME DECENT SNOW THE THE WRN AND NRN
MOUNTAINS TUESDAY INTO TUESDAY NIGHT. LIKELY POPS COVER THIS
PERIOD IN MOST OF THE WEST AND IN THE BIGHORN MTNS WITH A CHANCE
ACROSS THE LOWER ELEVATIONS OF THE NORTH. AFTER THAT...THE CHANGES
START. THE FIRST BIG DIFFERENCE IS HOW THE GULF OF ALASKA UPPER
LOW IS HANDLED. THE GFS TAKES THIS SYSTEM INLAND AND THEN SLIDES
IT SEWD DOWN THE BACK SIDE OF OUR RIDGE ALONG THE COAST RESULTING
IN A DECENT CHANCE OF SNOW WEDNESDAY NIGHT AND THURSDAY ACROSS ALL
BUT THE SW PART OF THE AREA. THE ECMWF WEAKENS THIS GULF OF ALASKA
LOW AS IT MOVES INLAND AND RUNS INTO THE CONFLUENT FLOW BETWEEN
THE WEST COAST RIDGE AND THE NNW FLOW FROM AROUND THE HUDSON BAY
LOW. ECMWF ENSEMBLES ALSO SUPPORT THE OP ECMWF. THE GEM SHOWS A
MORE GLANCING BLOW THAN THE GFS WITH WHAT`S LEFT OF THE GULF OF
ALASKA UPPER LOW WITH MAINLY A DRY FRONT CLIPPING THE NERN ZONES
WEDNESDAY NIGHT AND THURSDAY. LEANING MORE TOWARDS THE ECMWF EVEN
THOUGH IT HAS STRUGGLED OVER THE PAST SEVERAL DAYS. END RESULT FOR
OUR AREA IS WARMER TEMPERATURES FOR THANKSGIVING THAN THE GFS
WOULD INDICATE AND LITTLE IF ANY PCPN. WE WILL STILL NEED TO WATCH
IT CLOSELY. KEEPING SOME 20-30 POPS ACROSS THE WEST AND NORTH
WEDNESDAY NIGHT AND THEN DECREASING ON THANKSGIVING. FLAT RIDGE
HOLDS THROUGH THE END OF THE PERIOD WITH A POSSIBLE WEAK SHORTWAVE
MOVING IN ON SATURDAY FOR A CHANCE OF MTN SNOW IN THE WEST.
SHORTWAVE MOVING SOUTH TOWARDS THE NRN HIGH PLAINS MAY ALSO PUSH A
FRONT INTO THE NERN ZONES FRIDAY NIGHT AND SATURDAY.

&&

.AVIATION.../12Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES
AREAS OF LLWS WILL QUICKLY DEVELOP TONIGHT OVER THE CENTRAL BASINS
AS WEST WINDS FL075-100 INCREASE TO BETWEEN 35-50KTS EARLY THIS
MORNING.  THESE STRONGER WINDS WILL MIX DOWN TO THE SURFACE
FROM VCNTY 50NE SM KRKS-KCPR AND FROM VCNTY KCOD-KDUB WHERE HIGH
WIND WARNINGS ARE IN EFFECT.  A STRONG COLD FRONT WILL PUSH ACROSS
THE AREA EARLY SATURDAY EVENING.  MTNS WILL BE MOSTLY OBSCURED ALONG
THE DIVIDE AHEAD OF THE FRONT WITH SOME BLOW OVER PCPN IN THE VCNTY
OF KLND-KCOD DURING THE AFTERNOON.  A BAND OF SNOW WILL LIKELY
ACCOMPANY THE FRONT SATURDAY EVENING ALONG WITH AREAS OF MVFR/IFR
-SN MAINLY VCNTY ALONG AND EAST OF THE BIGHORN RANGE AND INTERSTATE
25.  AREAS OF SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL
FOLLOW THE FRONT...DECREASING AFTER 06Z SUNDAY.


WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES
SNOW AND MVFR/IFR CONDITIONS WILL INCREASE VCNTY AND NORTH OF A
KMM-KPNA LINE THROUGH 14Z WITH THESE CONDITIONS BECOMING WIDESPREAD
AFTER 14Z. LLWS WILL ALSO INCREASE ACROSS THE AREA EARLY THIS
MORNING AS FL075-100 WINDS INCREASE TO BTWN 35-50KTS.  A STRONG COLD
FRONT WILL PUSH ACROSS THE AREA SATURDAY AFTERNOON BRINGING
WIDESPREAD IFR...AREAS OF LIFR CONDITIONS IN SN/BLSN ALONG...AREAS
OF WEST SFC WIND 20-30KTS WITH GUSTS TO 40KTS.  SNOW AND WIND WILL
DECREASE AFTER 02Z SUNDAY BEHIND THE FRONT WITH NMRS SHSN LINGERING
OVER THE MOUNTAINS AND MAINLY SCT SHSN OVER THE VALLEYS WITH SOME
MORE ORGANIZED BANDING POSSIBLE...ESPECIALLY VCNTY KJAC-KAFO.
&&

.FIRE WEATHER...

A WINTER WEATHER SYSTEM WILL IMPACT WESTERN WYOMING THROUGH TODAY.
ADDITIONALLY...STRONG WIND WILL OCCUR ACROSS THE WIND CORRIDOR
BETWEEN ROCK SPRINGS AND CASPER...AND WILL ALSO DEVELOP IN THE
CODY FOOTHILLS. HIGH WIND WARNINGS ARE IN EFFECT FOR MUCH OF THE
DAY TODAY FOR THESE LOCATIONS. FIRE WEATHER BEHAVIOR IS
EXPECTED TO REMAIN MINIMAL UNDER THIS SYSTEM...WITH THE BEST
DISPERSION RATES OCCURRING DURING THE STORM.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM 6 AM THIS MORNING TO MIDNIGHT MST TONIGHT
WYZ003-019-020-022.

WINTER WEATHER ADVISORY UNTIL 6 AM MST SUNDAY WYZ016-026-027.

WINTER STORM WARNING UNTIL 6 AM MST SUNDAY
WYZ001-002-012>015-023>025.

HIGH WIND WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
WYZ010.

HIGH WIND WATCH FROM SUNDAY MORNING THROUGH SUNDAY AFTERNOON
WYZ016-017.

&&

$$

SHORT TERM...HATTINGS
LONG TERM...SKRBAC
AVIATION...AEM
FIRE WEATHER...HATTINGS










000
FXUS65 KRIW 220939
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
239 AM MST SAT NOV 22 2014

.SHORT TERM...SATURDAY THROUGH MONDAY NIGHT

WITH THE DIFFERENCES IN THE WEATHER ACROSS THE AREA WE WILL DIVIDE
THE DISCUSSION INTO WEST OF THE DIVIDE AND EAST OF THE DIVIDE.

WEST OF THE DIVIDE...IT LOOKS LIKE AN ACTIVE 36 HOURS OR SO AS THE
NEXT WEATHER MAKER NOW OVER IDAHO IN THE FORM OF A COLD FRONT AND
ASSOCIATED TROUGH MAKES ITS WAY TOWARD THE AREA. RADAR OUT OF OUR
NEIGHBORS TO THE WEST SHOW SOME SNOW MOVING INTO THE WESTERN
MOUNTAINS AND THE WEB CAMS CONFIRM THIS. THERE STILL LOOK TO BE TWO
DIFFERENT PARTS TO THIS SYSTEM. THE FIRST WILL BE THE WARM ADVECTION
THAT FALLS THIS MORNING. THE SECOND WILL BE THEN PASSAGE OF THE COLD
FRONT. THE MODELS CONTINUE TO BE IN FAIRLY GOOD AGREEMENT IN
BRINGING THE HEAVIEST PRECIPITATION FROM AROUND MID MORNING TO
AROUND EARLY AFTERNOON ACROSS MUCH OF THE AREA WITH THE FRONTAL
PASSAGE AND BEST UPPER LEVEL SUPPORT. CONTINUITY HANDLED THIS FAIRLY
WELL SO WE MADE FEW CHANGES TO THIS. THERE IS ONE CONCERN WE HAVE
HOWEVER. UNLIKE THE LAST SYSTEMS...THIS ONE IS PACIFIC IN ORIGIN AND
DOES NOT HAVE REALLY COLD AIR WITH IT. THE MODELS ARE SHOWING SOME
WARMER AIR THAT MAY ADVECT INTO THE WEST PRIOR TO THE PASSAGE OF THE
COLD FRONT. THE NAM SHOWS 700 MILLIBAR TEMPERATURES RISING TO AROUND
MINUS 3 THAT WOULD RAISE SNOW LEVELS TO AROUND 7000 FEET EARLY IN
THE AFTERNOON. THAT COULD LEAD TO SOME MIXING THAT COULD HOLD DOWN
ACCUMULATIONS. THE GFS IS COOLER BY ABOUT 1 TO 2 DEGREES CELSIUS AND
THAT WOULD KEEP THE PRECIPITATION MAINLY SNOW. FOR NOW...WE ALLOWED
FOR SOME MIXING IN SOME SOUTHERN PORTIONS OF THE HIGHLIGHT AREA
EARLY IN THE AFTERNOON BEFORE THE FRONTAL PASSAGE.

THE HEAVIEST SNOW SHOULD END THIS EVENING AS THE FORCING MOVES AWAY.
HOWEVER...WITH A SOMEWHAT MOIST WEST TO NORTHWESTERLY FLOW
CONTINUING OCCASIONAL SNOW WILL CONTINUE INTO TONIGHT AND INTO
TOMORROW AS WELL. TEMPERATURES WILL BE COLDER BUT NOT NEARLY AS COLD
AS LAST WEEK. ACCUMULATION WILL CONTINUE ALTHOUGH AT THIS POINT
ADDITIONAL AMOUNTS LOOK TO BE FAIRLY LIGHT. ANOTHER SPOKE OF ENERGY
IN THE FORM OF A SHORTWAVE COULD BRING SOME ADDITIONAL STEADIER SNOW
SUNDAY NIGHT AS WELL. WITH THE NORTHWEST FLOW CONTINUING SNOW
SHOWERS LOOK CONTINUE TO BE A GOOD BET RIGHT INTO MONDAY. AS ALWAYS
WITH NORTHWEST FLOW...THERE COULD BE A HEAVIER BAND THAT SETS UP BUT
PINPOINTING THESE IS IMPOSSIBLE. SOMETHING TO WATCH THOUGH.
TEMPERATURES ARE EXPECTED TO BE FAIRLY CLOSE TO NORMAL.

EAST OF THE DIVIDE...THE MAIN CONCERN HERE SHIFTS FROM THE THE WHITE
STUFF TO WIND. AHEAD OF THE COLD FRONT...IT LOOKS QUITE WINDY IN THE
FAVORED AREAS WITH SOUTHWEST FLOW. THE MODELS CONTINUE TO SHOW 50 TO
60 KNOTS ALOFT AND WITH SOME MIXING WE SHOULD SEE SOME WIND GUSTS TO
OVER 60 MPH ACROSS NATRONA COUNTY AS WELL AS THE RATTLESNAKE RANGE
AND CODY FOOTHILLS...ESPECIALLY NEAR THE GREAT CROSSROAD OF CLARK.
WINDS HAVE ALREADY GUSTED OVER 60 MPH THERE. WE THOUGHT ABOUT
DROPPING THE WARNING FOR CASPER MOUNTAIN...BUT WILL LEAVE IT FOR
NOW. AS FOR CHANCES OF PRECIPITATION...THEY LOOK FAIRLY SPARSE
DURING THE DAY AS DOWNSLOPING FLOW KEEPS THINGS DRY FOR MOST AREAS
EXCEPT THE MOUNTAINS. WE KEPT A SLIGHT CHANCE FOR MANY AREAS BUT
INCREASED IT TOWARD EVENING. THE EXCEPTION WOULD BE A PLACE LIKE
DUBOIS WHERE SOME BLOW OVER MAY BRING SNOW. THIS WILL ALSO BRING THE
WARMEST TEMPERATURES MANY AREAS HAVE SEEN SINCE A WEEK AGO ON
SUNDAY. THE GFS MOS NUMBERS ARE ESPECIALLY WARM...WARMING SOME AREAS
INTO THE 50S. WE KEPT THINGS A BUT COOLER FOR NOW THINKING THAT IF
IT GETS WARMER THAN THE PREDICTED HIGH TEMPERATURES...MOST PEOPLE
WILL BE HAPPY. IT WILL COOL OFF TONIGHT AFTER THE FRONT PASSES.
THERE IS THE CHANCE FOR SOME SNOW BANDS WITH THE NORTHWEST FLOW BUT
AGAIN THESE ARE IMPOSSIBLE TO PINPOINT UNTIL THEY FORM. SOMETHING TO
WATCH THOUGH.

WIND IS ONCE AGAIN THE PROBLEM FOR SUNDAY. HOWEVER...THE AREAS OF
CONCERN SWITCH TO THE FAVORED AREAS WITH NORTHWEST FLOW. THAT MEANS
PORTIONS OF NORTHERN JOHNSON COUNTY AS WELL AS THE WIND RIVER BASIN.
AGAIN WITH 700 MILLIBAR WINDS AROUND 50 KNOTS AS A RESULT WE HOISTED A
HIGH WIND WATCH FOR THESE AREAS FOR SUNDAY AND WILL CONTINUE IT AT
THIS TIME. THERE WILL STILL BE NORTHWEST FLOW AND CYCLONIC CURVATURE
OVER THE AREA AS WELL. THAT MEANS THE CHANCE FOR SOME SHOWERS
ALTHOUGH MOST AREAS SHOULD BE DRY MOST OF THE TIME. THE EXCEPTION
WOULD BE THE BIGHORN MOUNTAINS WHERE A FEW INCHES OF SNOW ARE
POSSIBLE. MONDAY LOOKS TO BE A SIMILAR DAY WITH SCATTERED SNOW
SHOWERS. WINDS SHOULD BE NOT QUITE AS STRONG...ALTHOUGH STILL GUSTY
FOR MOST AREAS.


.LONG TERM...TUESDAY THROUGH SATURDAY

MEDIUM RANGE MODELS START OUT IN PRETTY GOOD AGREEMENT BUT THEN
DIVERGE SIGNIFICANTLY FROM THANKSGIVING ONWARD. TO START THE
PERIOD ON TUESDAY...WE GET IN A DECENT ISENTROPIC UPGLIDE NW FLOW
PATTERN THAT COULD BRING SOME DECENT SNOW THE THE WRN AND NRN
MOUNTAINS TUESDAY INTO TUESDAY NIGHT. LIKELY POPS COVER THIS
PERIOD IN MOST OF THE WEST AND IN THE BIGHORN MTNS WITH A CHANCE
ACROSS THE LOWER ELEVATIONS OF THE NORTH. AFTER THAT...THE CHANGES
START. THE FIRST BIG DIFFERENCE IS HOW THE GULF OF ALASKA UPPER
LOW IS HANDLED. THE GFS TAKES THIS SYSTEM INLAND AND THEN SLIDES
IT SEWD DOWN THE BACK SIDE OF OUR RIDGE ALONG THE COAST RESULTING
IN A DECENT CHANCE OF SNOW WEDNESDAY NIGHT AND THURSDAY ACROSS ALL
BUT THE SW PART OF THE AREA. THE ECMWF WEAKENS THIS GULF OF ALASKA
LOW AS IT MOVES INLAND AND RUNS INTO THE CONFLUENT FLOW BETWEEN
THE WEST COAST RIDGE AND THE NNW FLOW FROM AROUND THE HUDSON BAY
LOW. ECMWF ENSEMBLES ALSO SUPPORT THE OP ECMWF. THE GEM SHOWS A
MORE GLANCING BLOW THAN THE GFS WITH WHAT`S LEFT OF THE GULF OF
ALASKA UPPER LOW WITH MAINLY A DRY FRONT CLIPPING THE NERN ZONES
WEDNESDAY NIGHT AND THURSDAY. LEANING MORE TOWARDS THE ECMWF EVEN
THOUGH IT HAS STRUGGLED OVER THE PAST SEVERAL DAYS. END RESULT FOR
OUR AREA IS WARMER TEMPERATURES FOR THANKSGIVING THAN THE GFS
WOULD INDICATE AND LITTLE IF ANY PCPN. WE WILL STILL NEED TO WATCH
IT CLOSELY. KEEPING SOME 20-30 POPS ACROSS THE WEST AND NORTH
WEDNESDAY NIGHT AND THEN DECREASING ON THANKSGIVING. FLAT RIDGE
HOLDS THROUGH THE END OF THE PERIOD WITH A POSSIBLE WEAK SHORTWAVE
MOVING IN ON SATURDAY FOR A CHANCE OF MTN SNOW IN THE WEST.
SHORTWAVE MOVING SOUTH TOWARDS THE NRN HIGH PLAINS MAY ALSO PUSH A
FRONT INTO THE NERN ZONES FRIDAY NIGHT AND SATURDAY.

&&

.AVIATION.../12Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES
AREAS OF LLWS WILL QUICKLY DEVELOP TONIGHT OVER THE CENTRAL BASINS
AS WEST WINDS FL075-100 INCREASE TO BETWEEN 35-50KTS EARLY THIS
MORNING.  THESE STRONGER WINDS WILL MIX DOWN TO THE SURFACE
FROM VCNTY 50NE SM KRKS-KCPR AND FROM VCNTY KCOD-KDUB WHERE HIGH
WIND WARNINGS ARE IN EFFECT.  A STRONG COLD FRONT WILL PUSH ACROSS
THE AREA EARLY SATURDAY EVENING.  MTNS WILL BE MOSTLY OBSCURED ALONG
THE DIVIDE AHEAD OF THE FRONT WITH SOME BLOW OVER PCPN IN THE VCNTY
OF KLND-KCOD DURING THE AFTERNOON.  A BAND OF SNOW WILL LIKELY
ACCOMPANY THE FRONT SATURDAY EVENING ALONG WITH AREAS OF MVFR/IFR
-SN MAINLY VCNTY ALONG AND EAST OF THE BIGHORN RANGE AND INTERSTATE
25.  AREAS OF SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL
FOLLOW THE FRONT...DECREASING AFTER 06Z SUNDAY.


WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES
SNOW AND MVFR/IFR CONDITIONS WILL INCREASE VCNTY AND NORTH OF A
KMM-KPNA LINE THROUGH 14Z WITH THESE CONDITIONS BECOMING WIDESPREAD
AFTER 14Z. LLWS WILL ALSO INCREASE ACROSS THE AREA EARLY THIS
MORNING AS FL075-100 WINDS INCREASE TO BTWN 35-50KTS.  A STRONG COLD
FRONT WILL PUSH ACROSS THE AREA SATURDAY AFTERNOON BRINGING
WIDESPREAD IFR...AREAS OF LIFR CONDITIONS IN SN/BLSN ALONG...AREAS
OF WEST SFC WIND 20-30KTS WITH GUSTS TO 40KTS.  SNOW AND WIND WILL
DECREASE AFTER 02Z SUNDAY BEHIND THE FRONT WITH NMRS SHSN LINGERING
OVER THE MOUNTAINS AND MAINLY SCT SHSN OVER THE VALLEYS WITH SOME
MORE ORGANIZED BANDING POSSIBLE...ESPECIALLY VCNTY KJAC-KAFO.
&&

.FIRE WEATHER...

A WINTER WEATHER SYSTEM WILL IMPACT WESTERN WYOMING THROUGH TODAY.
ADDITIONALLY...STRONG WIND WILL OCCUR ACROSS THE WIND CORRIDOR
BETWEEN ROCK SPRINGS AND CASPER...AND WILL ALSO DEVELOP IN THE
CODY FOOTHILLS. HIGH WIND WARNINGS ARE IN EFFECT FOR MUCH OF THE
DAY TODAY FOR THESE LOCATIONS. FIRE WEATHER BEHAVIOR IS
EXPECTED TO REMAIN MINIMAL UNDER THIS SYSTEM...WITH THE BEST
DISPERSION RATES OCCURRING DURING THE STORM.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM 6 AM THIS MORNING TO MIDNIGHT MST TONIGHT
WYZ003-019-020-022.

WINTER WEATHER ADVISORY UNTIL 6 AM MST SUNDAY WYZ016-026-027.

WINTER STORM WARNING UNTIL 6 AM MST SUNDAY
WYZ001-002-012>015-023>025.

HIGH WIND WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
WYZ010.

HIGH WIND WATCH FROM SUNDAY MORNING THROUGH SUNDAY AFTERNOON
WYZ016-017.

&&

$$

SHORT TERM...HATTINGS
LONG TERM...SKRBAC
AVIATION...AEM
FIRE WEATHER...HATTINGS











000
FXUS65 KRIW 220933
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
233 AM MST SAT NOV 22 2014

.SHORT TERM...SATURDAY THROUGH MONDAY NIGHT

WITH THE DIFFERENCES IN THE WEATHER ACROSS THE AREA WE WILL DIVIDE
THE DISCUSSION INTO WEST OF THE DIVIDE AND EAST OF THE DIVIDE.

WEST OF THE DIVIDE...IT LOOKS LIKE AN ACTIVE 36 HOURS OR SO AS THE
NEXT WEATHER MAKER NOW OVER IDAHO IN THE FORM OF A COLD FRONT AND
ASSOCIATED TROUGH MAKES ITS WAY TOWARD THE AREA. RADAR OUT OF OUR
NEIGHBORS TO THE WEST SHOW SOME SNOW MOVING INTO THE WESTERN
MOUNTAINS AND THE WEB CAMS CONFIRM THIS. THERE STILL LOOK TO BE TWO
DIFFERENT PARTS TO THIS SYSTEM. THE FIRST WILL BE THE WARM ADVECTION
THAT FALLS THIS MORNING. THE SECOND WILL BE THEN PASSAGE OF THE COLD
FRONT. THE MODELS CONTINUE TO BE IN FAIRLY GOOD AGREEMENT IN
BRINGING THE HEAVIEST PRECIPITATION FROM AROUND MID MORNING TO
AROUND EARLY AFTERNOON ACROSS MUCH OF THE AREA WITH THE FRONTAL
PASSAGE AND BEST UPPER LEVEL SUPPORT. CONTINUITY HANDLED THIS FAIRLY
WELL SO WE MADE FEW CHANGES TO THIS. THERE IS ONE CONCERN WE HAVE
HOWEVER. UNLIKE THE LAST SYSTEMS...THIS ONE IS PACIFIC IN ORIGIN AND
DOES NOT HAVE REALLY COLD AIR WITH IT. THE MODELS ARE SHOWING SOME
WARMER AIR THAT MAY ADVECT INTO THE WEST PRIOR TO THE PASSAGE OF THE
COLD FRONT. THE NAM SHOWS 700 MILLIBAR TEMPERATURES RISING TO AROUND
MINUS 3 THAT WOULD RAISE SNOW LEVELS TO AROUND 7000 FEET EARLY IN
THE AFTERNOON. THAT COULD LEAD TO SOME MIXING THAT COULD HOLD DOWN
ACCUMULATIONS. THE GFS IS COOLER BY ABOUT 1 TO 2 DEGREES CELSIUS AND
THAT WOULD KEEP THE PRECIPITATION MAINLY SNOW. FOR NOW...WE ALLOWED
FOR SOME MIXING IN SOME SOUTHERN PORTIONS OF THE HIGHLIGHT AREA
EARLY IN THE AFTERNOON BEFORE THE FRONTAL PASSAGE.

THE HEAVIEST SNOW SHOULD END THIS EVENING AS THE FORCING MOVES AWAY.
HOWEVER...WITH A SOMEWHAT MOIST WEST TO NORTHWESTERLY FLOW
CONTINUING OCCASIONAL SNOW WILL CONTINUE INTO TONIGHT AND INTO
TOMORROW AS WELL. TEMPERATURES WILL BE COLDER BUT NOT NEARLY AS COLD
AS LAST WEEK. ACCUMULATION WILL CONTINUE ALTHOUGH AT THIS POINT
ADDITIONAL AMOUNTS LOOK TO BE FAIRLY LIGHT. ANOTHER SPOKE OF ENERGY
IN THE FORM OF A SHORTWAVE COULD BRING SOME ADDITIONAL STEADIER SNOW
SUNDAY NIGHT AS WELL. WITH THE NORTHWEST FLOW CONTINUING SNOW
SHOWERS LOOK CONTINUE TO BE A GOOD BET RIGHT INTO MONDAY. AS ALWAYS
WITH NORTHWEST FLOW...THERE COULD BE A HEAVIER BAND THAT SETS UP BUT
PINPOINTING THESE IS IMPOSSIBLE. SOMETHING TO WATCH THOUGH.
TEMPERATURES ARE EXPECTED TO BE FAIRLY CLOSE TO NORMAL.

EAST OF THE DIVIDE...THE MAIN CONCERN HERE SHIFTS FROM THE THE WHITE
STUFF TO WIND. AHEAD OF THE COLD FRONT...IT LOOKS QUITE WINDY IN THE
FAVORED AREAS WITH SOUTHWEST FLOW. THE MODELS CONTINUE TO SHOW 50 TO
60 KNOTS ALOFT AND WITH SOME MIXING WE SHOULD SEE SOME WIND GUSTS TO
OVER 60 MPH ACROSS NATRONA COUNTY AS WELL AS THE RATTLESNAKE RANGE
AND CODY FOOTHILLS...ESPECIALLY NEAR THE GREAT CROSSROAD OF CLARK.
WINDS HAVE ALREADY GUSTED OVER 60 MPH THERE. WE THOUGHT ABOUT
DROPPING THE WARNING FOR CASPER MOUNTAIN...BUT WILL LEAVE IT FOR
NOW. AS FOR CHANCES OF PRECIPITATION...THEY LOOK FAIRLY SPARSE
DURING THE DAY AS DOWNSLOPING FLOW KEEPS THINGS DRY FOR MOST AREAS
EXCEPT THE MOUNTAINS. WE KEPT A SLIGHT CHANCE FOR MANY AREAS BUT
INCREASED IT TOWARD EVENING. THE EXCEPTION WOULD BE A PLACE LIKE
DUBOIS WHERE SOME BLOW OVER MAY BRING SNOW. THIS WILL ALSO BRING THE
WARMEST TEMPERATURES MANY AREAS HAVE SEEN SINCE A WEEK AGO ON
SUNDAY. THE GFS MOS NUMBERS ARE ESPECIALLY WARM...WARMING SOME AREAS
INTO THE 50S. WE KEPT THINGS A BUT COOLER FOR NOW THINKING THAT IF
IT GETS WARMER THAN THE PREDICTED HIGH TEMPERATURES...MOST PEOPLE
WILL BE HAPPY. IT WILL COOL OFF TONIGHT AFTER THE FRONT PASSES.
THERE IS THE CHANCE FOR SOME SNOW BANDS WITH THE NORTHWEST FLOW BUT
AGAIN THESE ARE IMPOSSIBLE TO PINPOINT UNTIL THEY FORM. SOMETHING TO
WATCH THOUGH.

WIND IS ONCE AGAIN THE PROBLEM FOR SUNDAY. HOWEVER...THE AREAS OF
CONCERN SWITCH TO THE FAVORED AREAS WITH NORTHWEST FLOW. THAT MEANS
PORTIONS OF NORTHERN JOHNSON COUNTY AS WELL AS THE WIND RIVER BASIN.
AGAIN WITH 700 MILLIBAR WINDS AROUND 50 KNOTS AS A RESULT WE HOISTED A
HIGH WIND WATCH FOR THESE AREAS FOR SUNDAY AND WILL CONTINUE IT AT
THIS TIME. THERE WILL STILL BE NORTHWEST FLOW AND CYCLONIC CURVATURE
OVER THE AREA AS WELL. THAT MEANS THE CHANCE FOR SOME SHOWERS
ALTHOUGH MOST AREAS SHOULD BE DRY MOST OF THE TIME. THE EXCEPTION
WOULD BE THE BIGHORN MOUNTAINS WHERE A FEW INCHES OF SNOW ARE
POSSIBLE. MONDAY LOOKS TO BE A SIMILAR DAY WITH SCATTERED SNOW
SHOWERS. WINDS SHOULD BE NOT QUITE AS STRONG...ALTHOUGH STILL GUSTY
FOR MOST AREAS.


.LONG TERM...TUESDAY THROUGH SATURDAY

MEDIUM RANGE MODELS START OUT IN PRETTY GOOD AGREEMENT BUT THEN
DIVERGE SIGNIFICANTLY FROM THANKSGIVING ONWARD. THE FIRST BIG
DIFFERENCE IS HOW THE GULF OF ALASKA UPPER LOW IS HANDLED. THE GFS
TAKES THIS SYSTEM INLAND AND THEN SLIDES IT SEWD DOWN THE BACK SIDE
OF OUR RIDGE ALONG THE COAST RESULTING IN A DECENT CHANCE OF SNOW
WEDNESDAY NIGHT AND THURSDAY ACROSS ALL BUT THE SW PART OF THE AREA.
THE ECMWF WEAKENS THIS GULF OF ALASKA LOW AS IT MOVES INLAND AND
RUNS INTO THE CONFLUENT FLOW BETWEEN THE WEST COAST RIDGE AND THE
NNW FLOW FROM AROUND THE HUDSON BAY LOW. ECMWF ENSEMBLES ALSO
SUPPORT THE OP ECMWF. THE GEM SHOWS A MORE GLANCING BLOW THAN THE GFS
WITH WHAT`S LEFT OF THE GULF OF ALASKA UPPER LOW WITH MAINLY A DRY
FRONT CLIPPING THE NERN ZONES WEDNESDAY NIGHT AND THURSDAY. LEANING
MORE TOWARDS THE ECMWF EVEN THOUGH IT HAS STRUGGLED OVER THE PAST
SEVERAL DAYS. END RESULT FOR OUR AREA IS WARMER TEMPERATURES FOR
THANKSGIVING THAN THE GFS WOULD INDICATE AND LITTLE IF ANY PCPN. WE
WILL STILL NEED TO WATCH IT CLOSELY. KEEPING SOME 20-30 POPS ACROSS
THE WEST AND NORTH WEDNESDAY NIGHT AND THEN DECREASING ON
THANKSGIVING. FLAT RIDGE HOLDS THROUGH THE END OF THE PERIOD WITH A
POSSIBLE WEAK SHORTWAVE MOVING IN ON SATURDAY FOR A CHANCE OF MTN
SNOW IN THE WEST. SHORTWAVE MOVING SOUTH TOWARDS THE NRN HIGH PLAINS
MAY ALSO PUSH A FRONT INTO THE NERN ZONES FRIDAY NIGHT AND SATURDAY.

&&

.AVIATION.../12Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES
AREAS OF LLWS WILL QUICKLY DEVELOP TONIGHT OVER THE CENTRAL BASINS
AS WEST WINDS FL075-100 INCREASE TO BETWEEN 35-50KTS EARLY THIS
MORNING.  THESE STRONGER WINDS WILL MIX DOWN TO THE SURFACE
FROM VCNTY 50NE SM KRKS-KCPR AND FROM VCNTY KCOD-KDUB WHERE HIGH
WIND WARNINGS ARE IN EFFECT.  A STRONG COLD FRONT WILL PUSH ACROSS
THE AREA EARLY SATURDAY EVENING.  MTNS WILL BE MOSTLY OBSCURED ALONG
THE DIVIDE AHEAD OF THE FRONT WITH SOME BLOW OVER PCPN IN THE VCNTY
OF KLND-KCOD DURING THE AFTERNOON.  A BAND OF SNOW WILL LIKELY
ACCOMPANY THE FRONT SATURDAY EVENING ALONG WITH AREAS OF MVFR/IFR
-SN MAINLY VCNTY ALONG AND EAST OF THE BIGHORN RANGE AND INTERSTATE
25.  AREAS OF SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL
FOLLOW THE FRONT...DECREASING AFTER 06Z SUNDAY.


WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES
SNOW AND MVFR/IFR CONDITIONS WILL INCREASE VCNTY AND NORTH OF A
KMM-KPNA LINE THROUGH 14Z WITH THESE CONDITIONS BECOMING WIDESPREAD
AFTER 14Z. LLWS WILL ALSO INCREASE ACROSS THE AREA EARLY THIS
MORNING AS FL075-100 WINDS INCREASE TO BTWN 35-50KTS.  A STRONG COLD
FRONT WILL PUSH ACROSS THE AREA SATURDAY AFTERNOON BRINGING
WIDESPREAD IFR...AREAS OF LIFR CONDITIONS IN SN/BLSN ALONG...AREAS
OF WEST SFC WIND 20-30KTS WITH GUSTS TO 40KTS.  SNOW AND WIND WILL
DECREASE AFTER 02Z SUNDAY BEHIND THE FRONT WITH NMRS SHSN LINGERING
OVER THE MOUNTAINS AND MAINLY SCT SHSN OVER THE VALLEYS WITH SOME
MORE ORGANIZED BANDING POSSIBLE...ESPECIALLY VCNTY KJAC-KAFO.
&&

.FIRE WEATHER...

A WINTER WEATHER SYSTEM WILL IMPACT WESTERN WYOMING THROUGH TODAY.
ADDITIONALLY...STRONG WIND WILL OCCUR ACROSS THE WIND CORRIDOR
BETWEEN ROCK SPRINGS AND CASPER...AND WILL ALSO DEVELOP IN THE
CODY FOOTHILLS. HIGH WIND WARNINGS ARE IN EFFECT FOR MUCH OF THE
DAY TODAY FOR THESE LOCATIONS. FIRE WEATHER BEHAVIOR IS
EXPECTED TO REMAIN MINIMAL UNDER THIS SYSTEM...WITH THE BEST
DISPERSION RATES OCCURRING DURING THE STORM.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM 6 AM THIS MORNING TO MIDNIGHT MST TONIGHT
WYZ003-019-020-022.

WINTER WEATHER ADVISORY UNTIL 6 AM MST SUNDAY WYZ016-026-027.

WINTER STORM WARNING UNTIL 6 AM MST SUNDAY
WYZ001-002-012>015-023>025.

HIGH WIND WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
WYZ010.

HIGH WIND WATCH FROM SUNDAY MORNING THROUGH SUNDAY AFTERNOON
WYZ016-017.

&&

$$

SHORT TERM...HATTINGS
LONG TERM...SKRBAC
AVIATION...AEM
FIRE WEATHER...HATTINGS









000
FXUS65 KRIW 220933
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
233 AM MST SAT NOV 22 2014

.SHORT TERM...SATURDAY THROUGH MONDAY NIGHT

WITH THE DIFFERENCES IN THE WEATHER ACROSS THE AREA WE WILL DIVIDE
THE DISCUSSION INTO WEST OF THE DIVIDE AND EAST OF THE DIVIDE.

WEST OF THE DIVIDE...IT LOOKS LIKE AN ACTIVE 36 HOURS OR SO AS THE
NEXT WEATHER MAKER NOW OVER IDAHO IN THE FORM OF A COLD FRONT AND
ASSOCIATED TROUGH MAKES ITS WAY TOWARD THE AREA. RADAR OUT OF OUR
NEIGHBORS TO THE WEST SHOW SOME SNOW MOVING INTO THE WESTERN
MOUNTAINS AND THE WEB CAMS CONFIRM THIS. THERE STILL LOOK TO BE TWO
DIFFERENT PARTS TO THIS SYSTEM. THE FIRST WILL BE THE WARM ADVECTION
THAT FALLS THIS MORNING. THE SECOND WILL BE THEN PASSAGE OF THE COLD
FRONT. THE MODELS CONTINUE TO BE IN FAIRLY GOOD AGREEMENT IN
BRINGING THE HEAVIEST PRECIPITATION FROM AROUND MID MORNING TO
AROUND EARLY AFTERNOON ACROSS MUCH OF THE AREA WITH THE FRONTAL
PASSAGE AND BEST UPPER LEVEL SUPPORT. CONTINUITY HANDLED THIS FAIRLY
WELL SO WE MADE FEW CHANGES TO THIS. THERE IS ONE CONCERN WE HAVE
HOWEVER. UNLIKE THE LAST SYSTEMS...THIS ONE IS PACIFIC IN ORIGIN AND
DOES NOT HAVE REALLY COLD AIR WITH IT. THE MODELS ARE SHOWING SOME
WARMER AIR THAT MAY ADVECT INTO THE WEST PRIOR TO THE PASSAGE OF THE
COLD FRONT. THE NAM SHOWS 700 MILLIBAR TEMPERATURES RISING TO AROUND
MINUS 3 THAT WOULD RAISE SNOW LEVELS TO AROUND 7000 FEET EARLY IN
THE AFTERNOON. THAT COULD LEAD TO SOME MIXING THAT COULD HOLD DOWN
ACCUMULATIONS. THE GFS IS COOLER BY ABOUT 1 TO 2 DEGREES CELSIUS AND
THAT WOULD KEEP THE PRECIPITATION MAINLY SNOW. FOR NOW...WE ALLOWED
FOR SOME MIXING IN SOME SOUTHERN PORTIONS OF THE HIGHLIGHT AREA
EARLY IN THE AFTERNOON BEFORE THE FRONTAL PASSAGE.

THE HEAVIEST SNOW SHOULD END THIS EVENING AS THE FORCING MOVES AWAY.
HOWEVER...WITH A SOMEWHAT MOIST WEST TO NORTHWESTERLY FLOW
CONTINUING OCCASIONAL SNOW WILL CONTINUE INTO TONIGHT AND INTO
TOMORROW AS WELL. TEMPERATURES WILL BE COLDER BUT NOT NEARLY AS COLD
AS LAST WEEK. ACCUMULATION WILL CONTINUE ALTHOUGH AT THIS POINT
ADDITIONAL AMOUNTS LOOK TO BE FAIRLY LIGHT. ANOTHER SPOKE OF ENERGY
IN THE FORM OF A SHORTWAVE COULD BRING SOME ADDITIONAL STEADIER SNOW
SUNDAY NIGHT AS WELL. WITH THE NORTHWEST FLOW CONTINUING SNOW
SHOWERS LOOK CONTINUE TO BE A GOOD BET RIGHT INTO MONDAY. AS ALWAYS
WITH NORTHWEST FLOW...THERE COULD BE A HEAVIER BAND THAT SETS UP BUT
PINPOINTING THESE IS IMPOSSIBLE. SOMETHING TO WATCH THOUGH.
TEMPERATURES ARE EXPECTED TO BE FAIRLY CLOSE TO NORMAL.

EAST OF THE DIVIDE...THE MAIN CONCERN HERE SHIFTS FROM THE THE WHITE
STUFF TO WIND. AHEAD OF THE COLD FRONT...IT LOOKS QUITE WINDY IN THE
FAVORED AREAS WITH SOUTHWEST FLOW. THE MODELS CONTINUE TO SHOW 50 TO
60 KNOTS ALOFT AND WITH SOME MIXING WE SHOULD SEE SOME WIND GUSTS TO
OVER 60 MPH ACROSS NATRONA COUNTY AS WELL AS THE RATTLESNAKE RANGE
AND CODY FOOTHILLS...ESPECIALLY NEAR THE GREAT CROSSROAD OF CLARK.
WINDS HAVE ALREADY GUSTED OVER 60 MPH THERE. WE THOUGHT ABOUT
DROPPING THE WARNING FOR CASPER MOUNTAIN...BUT WILL LEAVE IT FOR
NOW. AS FOR CHANCES OF PRECIPITATION...THEY LOOK FAIRLY SPARSE
DURING THE DAY AS DOWNSLOPING FLOW KEEPS THINGS DRY FOR MOST AREAS
EXCEPT THE MOUNTAINS. WE KEPT A SLIGHT CHANCE FOR MANY AREAS BUT
INCREASED IT TOWARD EVENING. THE EXCEPTION WOULD BE A PLACE LIKE
DUBOIS WHERE SOME BLOW OVER MAY BRING SNOW. THIS WILL ALSO BRING THE
WARMEST TEMPERATURES MANY AREAS HAVE SEEN SINCE A WEEK AGO ON
SUNDAY. THE GFS MOS NUMBERS ARE ESPECIALLY WARM...WARMING SOME AREAS
INTO THE 50S. WE KEPT THINGS A BUT COOLER FOR NOW THINKING THAT IF
IT GETS WARMER THAN THE PREDICTED HIGH TEMPERATURES...MOST PEOPLE
WILL BE HAPPY. IT WILL COOL OFF TONIGHT AFTER THE FRONT PASSES.
THERE IS THE CHANCE FOR SOME SNOW BANDS WITH THE NORTHWEST FLOW BUT
AGAIN THESE ARE IMPOSSIBLE TO PINPOINT UNTIL THEY FORM. SOMETHING TO
WATCH THOUGH.

WIND IS ONCE AGAIN THE PROBLEM FOR SUNDAY. HOWEVER...THE AREAS OF
CONCERN SWITCH TO THE FAVORED AREAS WITH NORTHWEST FLOW. THAT MEANS
PORTIONS OF NORTHERN JOHNSON COUNTY AS WELL AS THE WIND RIVER BASIN.
AGAIN WITH 700 MILLIBAR WINDS AROUND 50 KNOTS AS A RESULT WE HOISTED A
HIGH WIND WATCH FOR THESE AREAS FOR SUNDAY AND WILL CONTINUE IT AT
THIS TIME. THERE WILL STILL BE NORTHWEST FLOW AND CYCLONIC CURVATURE
OVER THE AREA AS WELL. THAT MEANS THE CHANCE FOR SOME SHOWERS
ALTHOUGH MOST AREAS SHOULD BE DRY MOST OF THE TIME. THE EXCEPTION
WOULD BE THE BIGHORN MOUNTAINS WHERE A FEW INCHES OF SNOW ARE
POSSIBLE. MONDAY LOOKS TO BE A SIMILAR DAY WITH SCATTERED SNOW
SHOWERS. WINDS SHOULD BE NOT QUITE AS STRONG...ALTHOUGH STILL GUSTY
FOR MOST AREAS.


.LONG TERM...TUESDAY THROUGH SATURDAY

MEDIUM RANGE MODELS START OUT IN PRETTY GOOD AGREEMENT BUT THEN
DIVERGE SIGNIFICANTLY FROM THANKSGIVING ONWARD. THE FIRST BIG
DIFFERENCE IS HOW THE GULF OF ALASKA UPPER LOW IS HANDLED. THE GFS
TAKES THIS SYSTEM INLAND AND THEN SLIDES IT SEWD DOWN THE BACK SIDE
OF OUR RIDGE ALONG THE COAST RESULTING IN A DECENT CHANCE OF SNOW
WEDNESDAY NIGHT AND THURSDAY ACROSS ALL BUT THE SW PART OF THE AREA.
THE ECMWF WEAKENS THIS GULF OF ALASKA LOW AS IT MOVES INLAND AND
RUNS INTO THE CONFLUENT FLOW BETWEEN THE WEST COAST RIDGE AND THE
NNW FLOW FROM AROUND THE HUDSON BAY LOW. ECMWF ENSEMBLES ALSO
SUPPORT THE OP ECMWF. THE GEM SHOWS A MORE GLANCING BLOW THAN THE GFS
WITH WHAT`S LEFT OF THE GULF OF ALASKA UPPER LOW WITH MAINLY A DRY
FRONT CLIPPING THE NERN ZONES WEDNESDAY NIGHT AND THURSDAY. LEANING
MORE TOWARDS THE ECMWF EVEN THOUGH IT HAS STRUGGLED OVER THE PAST
SEVERAL DAYS. END RESULT FOR OUR AREA IS WARMER TEMPERATURES FOR
THANKSGIVING THAN THE GFS WOULD INDICATE AND LITTLE IF ANY PCPN. WE
WILL STILL NEED TO WATCH IT CLOSELY. KEEPING SOME 20-30 POPS ACROSS
THE WEST AND NORTH WEDNESDAY NIGHT AND THEN DECREASING ON
THANKSGIVING. FLAT RIDGE HOLDS THROUGH THE END OF THE PERIOD WITH A
POSSIBLE WEAK SHORTWAVE MOVING IN ON SATURDAY FOR A CHANCE OF MTN
SNOW IN THE WEST. SHORTWAVE MOVING SOUTH TOWARDS THE NRN HIGH PLAINS
MAY ALSO PUSH A FRONT INTO THE NERN ZONES FRIDAY NIGHT AND SATURDAY.

&&

.AVIATION.../12Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES
AREAS OF LLWS WILL QUICKLY DEVELOP TONIGHT OVER THE CENTRAL BASINS
AS WEST WINDS FL075-100 INCREASE TO BETWEEN 35-50KTS EARLY THIS
MORNING.  THESE STRONGER WINDS WILL MIX DOWN TO THE SURFACE
FROM VCNTY 50NE SM KRKS-KCPR AND FROM VCNTY KCOD-KDUB WHERE HIGH
WIND WARNINGS ARE IN EFFECT.  A STRONG COLD FRONT WILL PUSH ACROSS
THE AREA EARLY SATURDAY EVENING.  MTNS WILL BE MOSTLY OBSCURED ALONG
THE DIVIDE AHEAD OF THE FRONT WITH SOME BLOW OVER PCPN IN THE VCNTY
OF KLND-KCOD DURING THE AFTERNOON.  A BAND OF SNOW WILL LIKELY
ACCOMPANY THE FRONT SATURDAY EVENING ALONG WITH AREAS OF MVFR/IFR
-SN MAINLY VCNTY ALONG AND EAST OF THE BIGHORN RANGE AND INTERSTATE
25.  AREAS OF SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL
FOLLOW THE FRONT...DECREASING AFTER 06Z SUNDAY.


WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES
SNOW AND MVFR/IFR CONDITIONS WILL INCREASE VCNTY AND NORTH OF A
KMM-KPNA LINE THROUGH 14Z WITH THESE CONDITIONS BECOMING WIDESPREAD
AFTER 14Z. LLWS WILL ALSO INCREASE ACROSS THE AREA EARLY THIS
MORNING AS FL075-100 WINDS INCREASE TO BTWN 35-50KTS.  A STRONG COLD
FRONT WILL PUSH ACROSS THE AREA SATURDAY AFTERNOON BRINGING
WIDESPREAD IFR...AREAS OF LIFR CONDITIONS IN SN/BLSN ALONG...AREAS
OF WEST SFC WIND 20-30KTS WITH GUSTS TO 40KTS.  SNOW AND WIND WILL
DECREASE AFTER 02Z SUNDAY BEHIND THE FRONT WITH NMRS SHSN LINGERING
OVER THE MOUNTAINS AND MAINLY SCT SHSN OVER THE VALLEYS WITH SOME
MORE ORGANIZED BANDING POSSIBLE...ESPECIALLY VCNTY KJAC-KAFO.
&&

.FIRE WEATHER...

A WINTER WEATHER SYSTEM WILL IMPACT WESTERN WYOMING THROUGH TODAY.
ADDITIONALLY...STRONG WIND WILL OCCUR ACROSS THE WIND CORRIDOR
BETWEEN ROCK SPRINGS AND CASPER...AND WILL ALSO DEVELOP IN THE
CODY FOOTHILLS. HIGH WIND WARNINGS ARE IN EFFECT FOR MUCH OF THE
DAY TODAY FOR THESE LOCATIONS. FIRE WEATHER BEHAVIOR IS
EXPECTED TO REMAIN MINIMAL UNDER THIS SYSTEM...WITH THE BEST
DISPERSION RATES OCCURRING DURING THE STORM.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM 6 AM THIS MORNING TO MIDNIGHT MST TONIGHT
WYZ003-019-020-022.

WINTER WEATHER ADVISORY UNTIL 6 AM MST SUNDAY WYZ016-026-027.

WINTER STORM WARNING UNTIL 6 AM MST SUNDAY
WYZ001-002-012>015-023>025.

HIGH WIND WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
WYZ010.

HIGH WIND WATCH FROM SUNDAY MORNING THROUGH SUNDAY AFTERNOON
WYZ016-017.

&&

$$

SHORT TERM...HATTINGS
LONG TERM...SKRBAC
AVIATION...AEM
FIRE WEATHER...HATTINGS










000
FXUS65 KRIW 220650
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1150 PM MST FRI NOV 21 2014

.SHORT TERM...TONIGHT THROUGH SATURDAY (ISSUED AT 242 MST)

AN INTERESTING PERIOD. RELATIVELY BENIGN CONDITIONS EXPECTED
DURING THE EARLY EVENING HOURS TONIGHT...WITH A SIGNIFICANT WINTER
SYSTEM EXPECTED TO IMPACT THE AREA DURING THE OVERNIGHT HOURS.
SNOWFALL WILL BEGIN BEFORE MIDNIGHT...WITH ACTIVITY AND COVERAGE
INCREASING THROUGH THE OVERNIGHT HOURS. SNOWFALL RATES WILL
INCREASE DURING THE MORNING HOURS...ESPECIALLY BETWEEN 0500 AND
1100 SATURDAY. SNOWFALL ASSOCIATED WITH THIS SYSTEM WILL CONTINUE
IMPACT THE AREA THROUGH SATURDAY...WITH ACTIVITY SPREADING TO
INCLUDE PORTIONS OF SOUTHERN WYOMING DURING SATURDAY AFTERNOON.

SNOWFALL ACCUMULATIONS WILL BE SIGNIFICANT ACROSS THE WESTERN
MOUNTAINS AND VALLEYS...WITH SOME LESSER AMOUNTS EXPECTED ACROSS
SOUTHERN WYOMING. STORM STORM WILL CONTINUE INTO SATURDAY
NIGHT...WITH FURTHER DETAILS ON TOTAL ACCUMULATIONS COVERED IN THE
LONG TERM SECTION.

.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
THE SHORTWAVE EJECTED BY THE LOW SPINNING AROUND IN THE ALEUTIANS
WILL BE CROSSING OVER OUR AREA AROUND 06Z SATURDAY NIGHT. AFTER THE
FROPA...THE SNOWFALL INTENSITY WILL BEGIN TO DIMINISH IN THE WEST.
HOWEVER...MANY AREAS OF SWEETWATER COUNTY SHOULD SEE 2 TO 3 INCHES
OF SNOWFALL SATURDAY NIGHT FROM THE COMBINATION OF THE ASCT STRONG
PACIFIC COLD FRONT AND Q VECTOR FORCING. THE WIND RIVER BASIN ALMOST
ALWAYS MANAGES TO RECEIVE AT LEAST JUST UNDER AN INCH OF SNOWFALL
WHENEVER CENTRAL WYOMING RECEIVES THE BRUNT OF THE 700MB COLD PUNCH
FROM A CLASSIC CATAFRONT LIKE THIS ONE AS WILL BE THE CASE SATURDAY
NIGHT...SO INCREASED POPS THERE AS WELL AS ADDED CORRESPONDING SNOW
ACCUMULATIONS THERE. JOHNSON COUNTY IS ANOTHER AREA TO WATCH FOR
MORE PRECIP SINCE THAT AREA WILL BE CLOSER TO THE 700MB LOW TRACKING
EAST SOUTHEAST ACROSS NORTH DAKOTA BUT THE PRECIP THERE WILL START
AS RAIN SO NOT EXPECTING TOO MUCH IN THE WAY OF ACCUMULATING SNOW
THERE. SNOW TOTALS OF 3 TO 5 INCHES WILL BE COMMON IN THE BIG HORN
MTNS.

AS FAR AS SNOW TOTALS GO IN THE FAR WEST...BY 12Z SUNDAY MORNING WE
WILL BE LOOKING AT 12 TO 20 INCHES IN THE TETONS...GROS VENTRE
RANGE...SALT AND WYOMING RANGES AND ALONG AND WEST OF THE DIVIDE IN
THE WIND RIVER MTNS ALONG WITH LOCAL AMOUNTS OF UP TO 26 INCHES. THE
JACKSON VALLEY CAN EXPECT 8 TO 12 INCHES WITH THE HIGHEST AMOUNTS
EXPECTED IN THE NORTH. THE STAR VALLEY WILL SEE 6 TO 8 INCHES.
SOUTHERN LINCOLN COUNTY WILL SEE 2 TO 4 INCHES AROUND OPAL AND 4 TO
8 INCHES AROUND COKEVILLE. YELLOWSTONE PARK WILL HAVE SNOW TOTALS
RANGING FROM 16 INCHES IN THE SOUTHWEST TO 3 TO 8 INCHES IN THE
NORTH INCLUDING MAMMOTH. THE ABSAROKAS WILL SEE UP TO A FOOT IN THE
WEST TO MAINLY 3 TO 10 INCHES IN THE EAST. AREAS JUST WEST OF DUBOIS
WILL SEE 4 TO 8 INCHES WITH 1 TO 3 INCHES JUST TO THE EAST. THE
UPPER GREEN RIVER FOOTHILLS WILL SEE AROUND 9 INCHES AT BONDURANT TO
5 INCHES IN PINEDALE. THE UPPER GREEN RIVER BASIN WILL SEE 3 TO 6
INCHES.

POST FRONTAL 7 TO 8MB...3 HOURLY SFC PRESSURE RISES WILL KEEP
POST FRONTAL NW WINDS UP THROUGH MID DAY SATURDAY IN THE 30 TO 40
MPH RANGE WITH GUSTS TO 50 MPH IN THE WIND RIVER BASIN AND NORTHERN
JOHNSON COUNTY. HIGH TEMPERATURES SUNDAY SHOULD BE 10 TO 15 DEGREES
COLDER SUNDAY THAN ON SATURDAY MOST AREAS. OCCASIONAL SNOWFALL WILL
CONTINUE THROUGH SUNDAY AND INTO MONDAY IN THE FAR WEST AS A SERIES
OF VORT LOBES PARADES WITHIN THE NORTHWEST FLOW WITH ONE DISTINCT
SHORTWAVE COMING THROUGH MONDAY. ON TUESDAY THE JET STREAM WILL PASS
OVERHEAD AS IT SLIDES OFF TO THE NORTHEAST OF US WHICH WILL PULL IN
MORE MOISTURE FROM THE NORTHWEST CONTINUING THE LIGHT TO
OCCASIONALLY MODERATE SNOW IN THE NORTHWEST MTNS. EXCEPT FOR SOME
CONTINUING LIGHT SNOW IN THE BIG HORN MTNS...AREAS EAST OF THE
DIVIDE WILL DRY OUT AFTER SATURDAY NIGHT. FOR THE REST OF THE
WEEK... TUESDAY NIGHT THROUGH THU...THE GFS AND THE EURO HAVE COME
MORE IN LINE WITH A HIGH PRESSURE RIDGE BUILDING IN FROM THE WEST
WITH A GRADUAL WARMING TREND. HOWEVER...WITH THE RIDGE AXIS STILL TO
THE WEST AND CONTINUING NW FLOW...WILL KEEP LOW POPS IN THE NORTHERN
AND CENTRAL MTNS FOR THIS TIME FRAME. WOULD RATHER WAIT FOR MORE RUN
TO RUN MODEL CONSISTENCY BEFORE WE WOULD BE WILLING TO TONE DOWN THE
MTN POPS ANY MORE THAN THEY ALREADY ARE...ESPECIALLY SINCE THIS IS A
SENSITIVE TIME OF THE MONTH GIVEN ALL THE HOLIDAY TRAVELERS.

&&

.AVIATION.../06Z ISSUANCE/
EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES AREAS OF LLWS
WILL QUICKLY DEVELOP TONIGHT OVER THE CENTRAL BASINS AS WEST WINDS
FL075-100 INCREASE TO BETWEEN 35-50KTS 06Z-12Z SATURDAY.  THESE
STRONGER WINDS WILL MIX DOWN TO THE SURFACE FROM VCNTY 50NE SM
KRKS-KCPR AND FROM VCNTY KCOD-KDUB WHERE HIGH WIND WARNINGS ARE IN
EFFECT.  A STRONG COLD FRONT WILL PUSH ACROSS THE AREA EARLY
SATURDAY EVENING.  MTNS WILL BE MOSTLY OBSCURED ALONG THE DIVIDE
AHEAD OF THE FRONT WITH SOME BLOW OVER PCPN IN THE VCNTY OF
KLND-KCOD DURING THE AFTERNOON.  A BAND OF SNOW WILL LIKELY
ACCOMPANY THE FRONT SATURDAY EVENING ALONG WITH AREAS OF MVFR/IFR
-SN MAINLY VCNTY ALONG AND EAST OF THE BIGHORN RANGE AND INTERSTATE
25.  AREAS OF SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL
FOLLOW THE FRONT...DECREASING AFTER 06Z SUNDAY.


WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES
SNOW AND MVFR/IFR CONDITIONS WILL INCREASE VCNTY AND NORTH OF A
KEMM-KPNA LINE 09Z-14Z WITH THESE CONDITIONS BECOMING WIDESPREAD
AFTER 14Z. LLWS WILL ALSO INCREASE ACROSS THE AREA EARLY THIS
MORNING AS FL075-100 WINDS INCREASE TO BTWN 35-50KTS.  A STRONG COLD
FRONT WILL PUSH ACROSS THE AREA SATURDAY AFTERNOON BRINGING
WIDESPREAD IFR...AREAS OF LIFR CONDITIONS IN SN/BLSN ALONG...AREAS
OF WEST SFC WIND 20-30KTS WITH GUSTS TO 40KTS.  SNOW AND WIND WILL
DECREASE AFTER 02Z SUNDAY BEHIND THE FRONT WITH NMRS SHSN LINGERING
OVER THE MOUNTAINS AND MAINLY SCT SHSN OVER THE VALLEYS WITH SOME
MORE ORGANIZED BANDING POSSIBLE...ESPECIALLY VCNTY KJAC-KAFO.

&&

.FIRE WEATHER...

A SIGNIFICANT WINTER WEATHER SYSTEM WILL BEGIN IMPACTING WESTERN
WYOMING THIS EVENING...AND SNOWFALL SPREADING TO INCLUDE MUCH OF
THE FORECAST AREA BY SATURDAY AFTERNOON. WINTER WEATHER HIGHLIGHTS
AREA IN EFFECT. ADDITIONALLY...STRONG WIND WILL DEVELOP ACROSS THE
WIND CORRIDOR BETWEEN ROCK SPRINGS AND CASPER...AND WILL ALSO
DEVELOP IN THE CODY FOOTHILLS. HIGH WIND WARNINGS ARE IN EFFECT
FOR MUCH OF THE DAY SATURDAY FOR THESE LOCATIONS. FIRE WEATHER
BEHAVIOR IS EXPECTED TO REMAIN MINIMAL UNDER THIS SYSTEM...WITH
THE BEST DISPERSION RATES OCCURRING DURING THE STORM. PLEASE SEE
THE APPROPRIATE WEATHER HIGHLIGHT PRODUCT FOR ADDITIONAL
INFORMATION REGARDING THE WINTER STORM AND HIGH WIND
WARNINGS...AND THE WINTER WEATHER ADVISORY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM 6 AM SATURDAY TO MIDNIGHT MST SATURDAY
NIGHT WYZ003-019-020-022.

WINTER WEATHER ADVISORY FROM 3 AM SATURDAY TO 6 AM MST SUNDAY
WYZ016-026-027.

WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 AM MST SUNDAY
WYZ001-002-012>015-023>025.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...LIPSON
AVIATION...AEM
FIRE WEATHER...BRANHAM











000
FXUS65 KRIW 220650
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1150 PM MST FRI NOV 21 2014

.SHORT TERM...TONIGHT THROUGH SATURDAY (ISSUED AT 242 MST)

AN INTERESTING PERIOD. RELATIVELY BENIGN CONDITIONS EXPECTED
DURING THE EARLY EVENING HOURS TONIGHT...WITH A SIGNIFICANT WINTER
SYSTEM EXPECTED TO IMPACT THE AREA DURING THE OVERNIGHT HOURS.
SNOWFALL WILL BEGIN BEFORE MIDNIGHT...WITH ACTIVITY AND COVERAGE
INCREASING THROUGH THE OVERNIGHT HOURS. SNOWFALL RATES WILL
INCREASE DURING THE MORNING HOURS...ESPECIALLY BETWEEN 0500 AND
1100 SATURDAY. SNOWFALL ASSOCIATED WITH THIS SYSTEM WILL CONTINUE
IMPACT THE AREA THROUGH SATURDAY...WITH ACTIVITY SPREADING TO
INCLUDE PORTIONS OF SOUTHERN WYOMING DURING SATURDAY AFTERNOON.

SNOWFALL ACCUMULATIONS WILL BE SIGNIFICANT ACROSS THE WESTERN
MOUNTAINS AND VALLEYS...WITH SOME LESSER AMOUNTS EXPECTED ACROSS
SOUTHERN WYOMING. STORM STORM WILL CONTINUE INTO SATURDAY
NIGHT...WITH FURTHER DETAILS ON TOTAL ACCUMULATIONS COVERED IN THE
LONG TERM SECTION.

.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
THE SHORTWAVE EJECTED BY THE LOW SPINNING AROUND IN THE ALEUTIANS
WILL BE CROSSING OVER OUR AREA AROUND 06Z SATURDAY NIGHT. AFTER THE
FROPA...THE SNOWFALL INTENSITY WILL BEGIN TO DIMINISH IN THE WEST.
HOWEVER...MANY AREAS OF SWEETWATER COUNTY SHOULD SEE 2 TO 3 INCHES
OF SNOWFALL SATURDAY NIGHT FROM THE COMBINATION OF THE ASCT STRONG
PACIFIC COLD FRONT AND Q VECTOR FORCING. THE WIND RIVER BASIN ALMOST
ALWAYS MANAGES TO RECEIVE AT LEAST JUST UNDER AN INCH OF SNOWFALL
WHENEVER CENTRAL WYOMING RECEIVES THE BRUNT OF THE 700MB COLD PUNCH
FROM A CLASSIC CATAFRONT LIKE THIS ONE AS WILL BE THE CASE SATURDAY
NIGHT...SO INCREASED POPS THERE AS WELL AS ADDED CORRESPONDING SNOW
ACCUMULATIONS THERE. JOHNSON COUNTY IS ANOTHER AREA TO WATCH FOR
MORE PRECIP SINCE THAT AREA WILL BE CLOSER TO THE 700MB LOW TRACKING
EAST SOUTHEAST ACROSS NORTH DAKOTA BUT THE PRECIP THERE WILL START
AS RAIN SO NOT EXPECTING TOO MUCH IN THE WAY OF ACCUMULATING SNOW
THERE. SNOW TOTALS OF 3 TO 5 INCHES WILL BE COMMON IN THE BIG HORN
MTNS.

AS FAR AS SNOW TOTALS GO IN THE FAR WEST...BY 12Z SUNDAY MORNING WE
WILL BE LOOKING AT 12 TO 20 INCHES IN THE TETONS...GROS VENTRE
RANGE...SALT AND WYOMING RANGES AND ALONG AND WEST OF THE DIVIDE IN
THE WIND RIVER MTNS ALONG WITH LOCAL AMOUNTS OF UP TO 26 INCHES. THE
JACKSON VALLEY CAN EXPECT 8 TO 12 INCHES WITH THE HIGHEST AMOUNTS
EXPECTED IN THE NORTH. THE STAR VALLEY WILL SEE 6 TO 8 INCHES.
SOUTHERN LINCOLN COUNTY WILL SEE 2 TO 4 INCHES AROUND OPAL AND 4 TO
8 INCHES AROUND COKEVILLE. YELLOWSTONE PARK WILL HAVE SNOW TOTALS
RANGING FROM 16 INCHES IN THE SOUTHWEST TO 3 TO 8 INCHES IN THE
NORTH INCLUDING MAMMOTH. THE ABSAROKAS WILL SEE UP TO A FOOT IN THE
WEST TO MAINLY 3 TO 10 INCHES IN THE EAST. AREAS JUST WEST OF DUBOIS
WILL SEE 4 TO 8 INCHES WITH 1 TO 3 INCHES JUST TO THE EAST. THE
UPPER GREEN RIVER FOOTHILLS WILL SEE AROUND 9 INCHES AT BONDURANT TO
5 INCHES IN PINEDALE. THE UPPER GREEN RIVER BASIN WILL SEE 3 TO 6
INCHES.

POST FRONTAL 7 TO 8MB...3 HOURLY SFC PRESSURE RISES WILL KEEP
POST FRONTAL NW WINDS UP THROUGH MID DAY SATURDAY IN THE 30 TO 40
MPH RANGE WITH GUSTS TO 50 MPH IN THE WIND RIVER BASIN AND NORTHERN
JOHNSON COUNTY. HIGH TEMPERATURES SUNDAY SHOULD BE 10 TO 15 DEGREES
COLDER SUNDAY THAN ON SATURDAY MOST AREAS. OCCASIONAL SNOWFALL WILL
CONTINUE THROUGH SUNDAY AND INTO MONDAY IN THE FAR WEST AS A SERIES
OF VORT LOBES PARADES WITHIN THE NORTHWEST FLOW WITH ONE DISTINCT
SHORTWAVE COMING THROUGH MONDAY. ON TUESDAY THE JET STREAM WILL PASS
OVERHEAD AS IT SLIDES OFF TO THE NORTHEAST OF US WHICH WILL PULL IN
MORE MOISTURE FROM THE NORTHWEST CONTINUING THE LIGHT TO
OCCASIONALLY MODERATE SNOW IN THE NORTHWEST MTNS. EXCEPT FOR SOME
CONTINUING LIGHT SNOW IN THE BIG HORN MTNS...AREAS EAST OF THE
DIVIDE WILL DRY OUT AFTER SATURDAY NIGHT. FOR THE REST OF THE
WEEK... TUESDAY NIGHT THROUGH THU...THE GFS AND THE EURO HAVE COME
MORE IN LINE WITH A HIGH PRESSURE RIDGE BUILDING IN FROM THE WEST
WITH A GRADUAL WARMING TREND. HOWEVER...WITH THE RIDGE AXIS STILL TO
THE WEST AND CONTINUING NW FLOW...WILL KEEP LOW POPS IN THE NORTHERN
AND CENTRAL MTNS FOR THIS TIME FRAME. WOULD RATHER WAIT FOR MORE RUN
TO RUN MODEL CONSISTENCY BEFORE WE WOULD BE WILLING TO TONE DOWN THE
MTN POPS ANY MORE THAN THEY ALREADY ARE...ESPECIALLY SINCE THIS IS A
SENSITIVE TIME OF THE MONTH GIVEN ALL THE HOLIDAY TRAVELERS.

&&

.AVIATION.../06Z ISSUANCE/
EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES AREAS OF LLWS
WILL QUICKLY DEVELOP TONIGHT OVER THE CENTRAL BASINS AS WEST WINDS
FL075-100 INCREASE TO BETWEEN 35-50KTS 06Z-12Z SATURDAY.  THESE
STRONGER WINDS WILL MIX DOWN TO THE SURFACE FROM VCNTY 50NE SM
KRKS-KCPR AND FROM VCNTY KCOD-KDUB WHERE HIGH WIND WARNINGS ARE IN
EFFECT.  A STRONG COLD FRONT WILL PUSH ACROSS THE AREA EARLY
SATURDAY EVENING.  MTNS WILL BE MOSTLY OBSCURED ALONG THE DIVIDE
AHEAD OF THE FRONT WITH SOME BLOW OVER PCPN IN THE VCNTY OF
KLND-KCOD DURING THE AFTERNOON.  A BAND OF SNOW WILL LIKELY
ACCOMPANY THE FRONT SATURDAY EVENING ALONG WITH AREAS OF MVFR/IFR
-SN MAINLY VCNTY ALONG AND EAST OF THE BIGHORN RANGE AND INTERSTATE
25.  AREAS OF SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL
FOLLOW THE FRONT...DECREASING AFTER 06Z SUNDAY.


WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES
SNOW AND MVFR/IFR CONDITIONS WILL INCREASE VCNTY AND NORTH OF A
KEMM-KPNA LINE 09Z-14Z WITH THESE CONDITIONS BECOMING WIDESPREAD
AFTER 14Z. LLWS WILL ALSO INCREASE ACROSS THE AREA EARLY THIS
MORNING AS FL075-100 WINDS INCREASE TO BTWN 35-50KTS.  A STRONG COLD
FRONT WILL PUSH ACROSS THE AREA SATURDAY AFTERNOON BRINGING
WIDESPREAD IFR...AREAS OF LIFR CONDITIONS IN SN/BLSN ALONG...AREAS
OF WEST SFC WIND 20-30KTS WITH GUSTS TO 40KTS.  SNOW AND WIND WILL
DECREASE AFTER 02Z SUNDAY BEHIND THE FRONT WITH NMRS SHSN LINGERING
OVER THE MOUNTAINS AND MAINLY SCT SHSN OVER THE VALLEYS WITH SOME
MORE ORGANIZED BANDING POSSIBLE...ESPECIALLY VCNTY KJAC-KAFO.

&&

.FIRE WEATHER...

A SIGNIFICANT WINTER WEATHER SYSTEM WILL BEGIN IMPACTING WESTERN
WYOMING THIS EVENING...AND SNOWFALL SPREADING TO INCLUDE MUCH OF
THE FORECAST AREA BY SATURDAY AFTERNOON. WINTER WEATHER HIGHLIGHTS
AREA IN EFFECT. ADDITIONALLY...STRONG WIND WILL DEVELOP ACROSS THE
WIND CORRIDOR BETWEEN ROCK SPRINGS AND CASPER...AND WILL ALSO
DEVELOP IN THE CODY FOOTHILLS. HIGH WIND WARNINGS ARE IN EFFECT
FOR MUCH OF THE DAY SATURDAY FOR THESE LOCATIONS. FIRE WEATHER
BEHAVIOR IS EXPECTED TO REMAIN MINIMAL UNDER THIS SYSTEM...WITH
THE BEST DISPERSION RATES OCCURRING DURING THE STORM. PLEASE SEE
THE APPROPRIATE WEATHER HIGHLIGHT PRODUCT FOR ADDITIONAL
INFORMATION REGARDING THE WINTER STORM AND HIGH WIND
WARNINGS...AND THE WINTER WEATHER ADVISORY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM 6 AM SATURDAY TO MIDNIGHT MST SATURDAY
NIGHT WYZ003-019-020-022.

WINTER WEATHER ADVISORY FROM 3 AM SATURDAY TO 6 AM MST SUNDAY
WYZ016-026-027.

WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 AM MST SUNDAY
WYZ001-002-012>015-023>025.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...LIPSON
AVIATION...AEM
FIRE WEATHER...BRANHAM











000
FXUS65 KRIW 220650
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1150 PM MST FRI NOV 21 2014

.SHORT TERM...TONIGHT THROUGH SATURDAY (ISSUED AT 242 MST)

AN INTERESTING PERIOD. RELATIVELY BENIGN CONDITIONS EXPECTED
DURING THE EARLY EVENING HOURS TONIGHT...WITH A SIGNIFICANT WINTER
SYSTEM EXPECTED TO IMPACT THE AREA DURING THE OVERNIGHT HOURS.
SNOWFALL WILL BEGIN BEFORE MIDNIGHT...WITH ACTIVITY AND COVERAGE
INCREASING THROUGH THE OVERNIGHT HOURS. SNOWFALL RATES WILL
INCREASE DURING THE MORNING HOURS...ESPECIALLY BETWEEN 0500 AND
1100 SATURDAY. SNOWFALL ASSOCIATED WITH THIS SYSTEM WILL CONTINUE
IMPACT THE AREA THROUGH SATURDAY...WITH ACTIVITY SPREADING TO
INCLUDE PORTIONS OF SOUTHERN WYOMING DURING SATURDAY AFTERNOON.

SNOWFALL ACCUMULATIONS WILL BE SIGNIFICANT ACROSS THE WESTERN
MOUNTAINS AND VALLEYS...WITH SOME LESSER AMOUNTS EXPECTED ACROSS
SOUTHERN WYOMING. STORM STORM WILL CONTINUE INTO SATURDAY
NIGHT...WITH FURTHER DETAILS ON TOTAL ACCUMULATIONS COVERED IN THE
LONG TERM SECTION.

.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
THE SHORTWAVE EJECTED BY THE LOW SPINNING AROUND IN THE ALEUTIANS
WILL BE CROSSING OVER OUR AREA AROUND 06Z SATURDAY NIGHT. AFTER THE
FROPA...THE SNOWFALL INTENSITY WILL BEGIN TO DIMINISH IN THE WEST.
HOWEVER...MANY AREAS OF SWEETWATER COUNTY SHOULD SEE 2 TO 3 INCHES
OF SNOWFALL SATURDAY NIGHT FROM THE COMBINATION OF THE ASCT STRONG
PACIFIC COLD FRONT AND Q VECTOR FORCING. THE WIND RIVER BASIN ALMOST
ALWAYS MANAGES TO RECEIVE AT LEAST JUST UNDER AN INCH OF SNOWFALL
WHENEVER CENTRAL WYOMING RECEIVES THE BRUNT OF THE 700MB COLD PUNCH
FROM A CLASSIC CATAFRONT LIKE THIS ONE AS WILL BE THE CASE SATURDAY
NIGHT...SO INCREASED POPS THERE AS WELL AS ADDED CORRESPONDING SNOW
ACCUMULATIONS THERE. JOHNSON COUNTY IS ANOTHER AREA TO WATCH FOR
MORE PRECIP SINCE THAT AREA WILL BE CLOSER TO THE 700MB LOW TRACKING
EAST SOUTHEAST ACROSS NORTH DAKOTA BUT THE PRECIP THERE WILL START
AS RAIN SO NOT EXPECTING TOO MUCH IN THE WAY OF ACCUMULATING SNOW
THERE. SNOW TOTALS OF 3 TO 5 INCHES WILL BE COMMON IN THE BIG HORN
MTNS.

AS FAR AS SNOW TOTALS GO IN THE FAR WEST...BY 12Z SUNDAY MORNING WE
WILL BE LOOKING AT 12 TO 20 INCHES IN THE TETONS...GROS VENTRE
RANGE...SALT AND WYOMING RANGES AND ALONG AND WEST OF THE DIVIDE IN
THE WIND RIVER MTNS ALONG WITH LOCAL AMOUNTS OF UP TO 26 INCHES. THE
JACKSON VALLEY CAN EXPECT 8 TO 12 INCHES WITH THE HIGHEST AMOUNTS
EXPECTED IN THE NORTH. THE STAR VALLEY WILL SEE 6 TO 8 INCHES.
SOUTHERN LINCOLN COUNTY WILL SEE 2 TO 4 INCHES AROUND OPAL AND 4 TO
8 INCHES AROUND COKEVILLE. YELLOWSTONE PARK WILL HAVE SNOW TOTALS
RANGING FROM 16 INCHES IN THE SOUTHWEST TO 3 TO 8 INCHES IN THE
NORTH INCLUDING MAMMOTH. THE ABSAROKAS WILL SEE UP TO A FOOT IN THE
WEST TO MAINLY 3 TO 10 INCHES IN THE EAST. AREAS JUST WEST OF DUBOIS
WILL SEE 4 TO 8 INCHES WITH 1 TO 3 INCHES JUST TO THE EAST. THE
UPPER GREEN RIVER FOOTHILLS WILL SEE AROUND 9 INCHES AT BONDURANT TO
5 INCHES IN PINEDALE. THE UPPER GREEN RIVER BASIN WILL SEE 3 TO 6
INCHES.

POST FRONTAL 7 TO 8MB...3 HOURLY SFC PRESSURE RISES WILL KEEP
POST FRONTAL NW WINDS UP THROUGH MID DAY SATURDAY IN THE 30 TO 40
MPH RANGE WITH GUSTS TO 50 MPH IN THE WIND RIVER BASIN AND NORTHERN
JOHNSON COUNTY. HIGH TEMPERATURES SUNDAY SHOULD BE 10 TO 15 DEGREES
COLDER SUNDAY THAN ON SATURDAY MOST AREAS. OCCASIONAL SNOWFALL WILL
CONTINUE THROUGH SUNDAY AND INTO MONDAY IN THE FAR WEST AS A SERIES
OF VORT LOBES PARADES WITHIN THE NORTHWEST FLOW WITH ONE DISTINCT
SHORTWAVE COMING THROUGH MONDAY. ON TUESDAY THE JET STREAM WILL PASS
OVERHEAD AS IT SLIDES OFF TO THE NORTHEAST OF US WHICH WILL PULL IN
MORE MOISTURE FROM THE NORTHWEST CONTINUING THE LIGHT TO
OCCASIONALLY MODERATE SNOW IN THE NORTHWEST MTNS. EXCEPT FOR SOME
CONTINUING LIGHT SNOW IN THE BIG HORN MTNS...AREAS EAST OF THE
DIVIDE WILL DRY OUT AFTER SATURDAY NIGHT. FOR THE REST OF THE
WEEK... TUESDAY NIGHT THROUGH THU...THE GFS AND THE EURO HAVE COME
MORE IN LINE WITH A HIGH PRESSURE RIDGE BUILDING IN FROM THE WEST
WITH A GRADUAL WARMING TREND. HOWEVER...WITH THE RIDGE AXIS STILL TO
THE WEST AND CONTINUING NW FLOW...WILL KEEP LOW POPS IN THE NORTHERN
AND CENTRAL MTNS FOR THIS TIME FRAME. WOULD RATHER WAIT FOR MORE RUN
TO RUN MODEL CONSISTENCY BEFORE WE WOULD BE WILLING TO TONE DOWN THE
MTN POPS ANY MORE THAN THEY ALREADY ARE...ESPECIALLY SINCE THIS IS A
SENSITIVE TIME OF THE MONTH GIVEN ALL THE HOLIDAY TRAVELERS.

&&

.AVIATION.../06Z ISSUANCE/
EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES AREAS OF LLWS
WILL QUICKLY DEVELOP TONIGHT OVER THE CENTRAL BASINS AS WEST WINDS
FL075-100 INCREASE TO BETWEEN 35-50KTS 06Z-12Z SATURDAY.  THESE
STRONGER WINDS WILL MIX DOWN TO THE SURFACE FROM VCNTY 50NE SM
KRKS-KCPR AND FROM VCNTY KCOD-KDUB WHERE HIGH WIND WARNINGS ARE IN
EFFECT.  A STRONG COLD FRONT WILL PUSH ACROSS THE AREA EARLY
SATURDAY EVENING.  MTNS WILL BE MOSTLY OBSCURED ALONG THE DIVIDE
AHEAD OF THE FRONT WITH SOME BLOW OVER PCPN IN THE VCNTY OF
KLND-KCOD DURING THE AFTERNOON.  A BAND OF SNOW WILL LIKELY
ACCOMPANY THE FRONT SATURDAY EVENING ALONG WITH AREAS OF MVFR/IFR
-SN MAINLY VCNTY ALONG AND EAST OF THE BIGHORN RANGE AND INTERSTATE
25.  AREAS OF SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL
FOLLOW THE FRONT...DECREASING AFTER 06Z SUNDAY.


WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES
SNOW AND MVFR/IFR CONDITIONS WILL INCREASE VCNTY AND NORTH OF A
KEMM-KPNA LINE 09Z-14Z WITH THESE CONDITIONS BECOMING WIDESPREAD
AFTER 14Z. LLWS WILL ALSO INCREASE ACROSS THE AREA EARLY THIS
MORNING AS FL075-100 WINDS INCREASE TO BTWN 35-50KTS.  A STRONG COLD
FRONT WILL PUSH ACROSS THE AREA SATURDAY AFTERNOON BRINGING
WIDESPREAD IFR...AREAS OF LIFR CONDITIONS IN SN/BLSN ALONG...AREAS
OF WEST SFC WIND 20-30KTS WITH GUSTS TO 40KTS.  SNOW AND WIND WILL
DECREASE AFTER 02Z SUNDAY BEHIND THE FRONT WITH NMRS SHSN LINGERING
OVER THE MOUNTAINS AND MAINLY SCT SHSN OVER THE VALLEYS WITH SOME
MORE ORGANIZED BANDING POSSIBLE...ESPECIALLY VCNTY KJAC-KAFO.

&&

.FIRE WEATHER...

A SIGNIFICANT WINTER WEATHER SYSTEM WILL BEGIN IMPACTING WESTERN
WYOMING THIS EVENING...AND SNOWFALL SPREADING TO INCLUDE MUCH OF
THE FORECAST AREA BY SATURDAY AFTERNOON. WINTER WEATHER HIGHLIGHTS
AREA IN EFFECT. ADDITIONALLY...STRONG WIND WILL DEVELOP ACROSS THE
WIND CORRIDOR BETWEEN ROCK SPRINGS AND CASPER...AND WILL ALSO
DEVELOP IN THE CODY FOOTHILLS. HIGH WIND WARNINGS ARE IN EFFECT
FOR MUCH OF THE DAY SATURDAY FOR THESE LOCATIONS. FIRE WEATHER
BEHAVIOR IS EXPECTED TO REMAIN MINIMAL UNDER THIS SYSTEM...WITH
THE BEST DISPERSION RATES OCCURRING DURING THE STORM. PLEASE SEE
THE APPROPRIATE WEATHER HIGHLIGHT PRODUCT FOR ADDITIONAL
INFORMATION REGARDING THE WINTER STORM AND HIGH WIND
WARNINGS...AND THE WINTER WEATHER ADVISORY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM 6 AM SATURDAY TO MIDNIGHT MST SATURDAY
NIGHT WYZ003-019-020-022.

WINTER WEATHER ADVISORY FROM 3 AM SATURDAY TO 6 AM MST SUNDAY
WYZ016-026-027.

WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 AM MST SUNDAY
WYZ001-002-012>015-023>025.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...LIPSON
AVIATION...AEM
FIRE WEATHER...BRANHAM











000
FXUS65 KRIW 220650
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1150 PM MST FRI NOV 21 2014

.SHORT TERM...TONIGHT THROUGH SATURDAY (ISSUED AT 242 MST)

AN INTERESTING PERIOD. RELATIVELY BENIGN CONDITIONS EXPECTED
DURING THE EARLY EVENING HOURS TONIGHT...WITH A SIGNIFICANT WINTER
SYSTEM EXPECTED TO IMPACT THE AREA DURING THE OVERNIGHT HOURS.
SNOWFALL WILL BEGIN BEFORE MIDNIGHT...WITH ACTIVITY AND COVERAGE
INCREASING THROUGH THE OVERNIGHT HOURS. SNOWFALL RATES WILL
INCREASE DURING THE MORNING HOURS...ESPECIALLY BETWEEN 0500 AND
1100 SATURDAY. SNOWFALL ASSOCIATED WITH THIS SYSTEM WILL CONTINUE
IMPACT THE AREA THROUGH SATURDAY...WITH ACTIVITY SPREADING TO
INCLUDE PORTIONS OF SOUTHERN WYOMING DURING SATURDAY AFTERNOON.

SNOWFALL ACCUMULATIONS WILL BE SIGNIFICANT ACROSS THE WESTERN
MOUNTAINS AND VALLEYS...WITH SOME LESSER AMOUNTS EXPECTED ACROSS
SOUTHERN WYOMING. STORM STORM WILL CONTINUE INTO SATURDAY
NIGHT...WITH FURTHER DETAILS ON TOTAL ACCUMULATIONS COVERED IN THE
LONG TERM SECTION.

.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
THE SHORTWAVE EJECTED BY THE LOW SPINNING AROUND IN THE ALEUTIANS
WILL BE CROSSING OVER OUR AREA AROUND 06Z SATURDAY NIGHT. AFTER THE
FROPA...THE SNOWFALL INTENSITY WILL BEGIN TO DIMINISH IN THE WEST.
HOWEVER...MANY AREAS OF SWEETWATER COUNTY SHOULD SEE 2 TO 3 INCHES
OF SNOWFALL SATURDAY NIGHT FROM THE COMBINATION OF THE ASCT STRONG
PACIFIC COLD FRONT AND Q VECTOR FORCING. THE WIND RIVER BASIN ALMOST
ALWAYS MANAGES TO RECEIVE AT LEAST JUST UNDER AN INCH OF SNOWFALL
WHENEVER CENTRAL WYOMING RECEIVES THE BRUNT OF THE 700MB COLD PUNCH
FROM A CLASSIC CATAFRONT LIKE THIS ONE AS WILL BE THE CASE SATURDAY
NIGHT...SO INCREASED POPS THERE AS WELL AS ADDED CORRESPONDING SNOW
ACCUMULATIONS THERE. JOHNSON COUNTY IS ANOTHER AREA TO WATCH FOR
MORE PRECIP SINCE THAT AREA WILL BE CLOSER TO THE 700MB LOW TRACKING
EAST SOUTHEAST ACROSS NORTH DAKOTA BUT THE PRECIP THERE WILL START
AS RAIN SO NOT EXPECTING TOO MUCH IN THE WAY OF ACCUMULATING SNOW
THERE. SNOW TOTALS OF 3 TO 5 INCHES WILL BE COMMON IN THE BIG HORN
MTNS.

AS FAR AS SNOW TOTALS GO IN THE FAR WEST...BY 12Z SUNDAY MORNING WE
WILL BE LOOKING AT 12 TO 20 INCHES IN THE TETONS...GROS VENTRE
RANGE...SALT AND WYOMING RANGES AND ALONG AND WEST OF THE DIVIDE IN
THE WIND RIVER MTNS ALONG WITH LOCAL AMOUNTS OF UP TO 26 INCHES. THE
JACKSON VALLEY CAN EXPECT 8 TO 12 INCHES WITH THE HIGHEST AMOUNTS
EXPECTED IN THE NORTH. THE STAR VALLEY WILL SEE 6 TO 8 INCHES.
SOUTHERN LINCOLN COUNTY WILL SEE 2 TO 4 INCHES AROUND OPAL AND 4 TO
8 INCHES AROUND COKEVILLE. YELLOWSTONE PARK WILL HAVE SNOW TOTALS
RANGING FROM 16 INCHES IN THE SOUTHWEST TO 3 TO 8 INCHES IN THE
NORTH INCLUDING MAMMOTH. THE ABSAROKAS WILL SEE UP TO A FOOT IN THE
WEST TO MAINLY 3 TO 10 INCHES IN THE EAST. AREAS JUST WEST OF DUBOIS
WILL SEE 4 TO 8 INCHES WITH 1 TO 3 INCHES JUST TO THE EAST. THE
UPPER GREEN RIVER FOOTHILLS WILL SEE AROUND 9 INCHES AT BONDURANT TO
5 INCHES IN PINEDALE. THE UPPER GREEN RIVER BASIN WILL SEE 3 TO 6
INCHES.

POST FRONTAL 7 TO 8MB...3 HOURLY SFC PRESSURE RISES WILL KEEP
POST FRONTAL NW WINDS UP THROUGH MID DAY SATURDAY IN THE 30 TO 40
MPH RANGE WITH GUSTS TO 50 MPH IN THE WIND RIVER BASIN AND NORTHERN
JOHNSON COUNTY. HIGH TEMPERATURES SUNDAY SHOULD BE 10 TO 15 DEGREES
COLDER SUNDAY THAN ON SATURDAY MOST AREAS. OCCASIONAL SNOWFALL WILL
CONTINUE THROUGH SUNDAY AND INTO MONDAY IN THE FAR WEST AS A SERIES
OF VORT LOBES PARADES WITHIN THE NORTHWEST FLOW WITH ONE DISTINCT
SHORTWAVE COMING THROUGH MONDAY. ON TUESDAY THE JET STREAM WILL PASS
OVERHEAD AS IT SLIDES OFF TO THE NORTHEAST OF US WHICH WILL PULL IN
MORE MOISTURE FROM THE NORTHWEST CONTINUING THE LIGHT TO
OCCASIONALLY MODERATE SNOW IN THE NORTHWEST MTNS. EXCEPT FOR SOME
CONTINUING LIGHT SNOW IN THE BIG HORN MTNS...AREAS EAST OF THE
DIVIDE WILL DRY OUT AFTER SATURDAY NIGHT. FOR THE REST OF THE
WEEK... TUESDAY NIGHT THROUGH THU...THE GFS AND THE EURO HAVE COME
MORE IN LINE WITH A HIGH PRESSURE RIDGE BUILDING IN FROM THE WEST
WITH A GRADUAL WARMING TREND. HOWEVER...WITH THE RIDGE AXIS STILL TO
THE WEST AND CONTINUING NW FLOW...WILL KEEP LOW POPS IN THE NORTHERN
AND CENTRAL MTNS FOR THIS TIME FRAME. WOULD RATHER WAIT FOR MORE RUN
TO RUN MODEL CONSISTENCY BEFORE WE WOULD BE WILLING TO TONE DOWN THE
MTN POPS ANY MORE THAN THEY ALREADY ARE...ESPECIALLY SINCE THIS IS A
SENSITIVE TIME OF THE MONTH GIVEN ALL THE HOLIDAY TRAVELERS.

&&

.AVIATION.../06Z ISSUANCE/
EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES AREAS OF LLWS
WILL QUICKLY DEVELOP TONIGHT OVER THE CENTRAL BASINS AS WEST WINDS
FL075-100 INCREASE TO BETWEEN 35-50KTS 06Z-12Z SATURDAY.  THESE
STRONGER WINDS WILL MIX DOWN TO THE SURFACE FROM VCNTY 50NE SM
KRKS-KCPR AND FROM VCNTY KCOD-KDUB WHERE HIGH WIND WARNINGS ARE IN
EFFECT.  A STRONG COLD FRONT WILL PUSH ACROSS THE AREA EARLY
SATURDAY EVENING.  MTNS WILL BE MOSTLY OBSCURED ALONG THE DIVIDE
AHEAD OF THE FRONT WITH SOME BLOW OVER PCPN IN THE VCNTY OF
KLND-KCOD DURING THE AFTERNOON.  A BAND OF SNOW WILL LIKELY
ACCOMPANY THE FRONT SATURDAY EVENING ALONG WITH AREAS OF MVFR/IFR
-SN MAINLY VCNTY ALONG AND EAST OF THE BIGHORN RANGE AND INTERSTATE
25.  AREAS OF SFC NW WINDS AT 20-30KTS WITH GUSTS TO 40KTS WILL
FOLLOW THE FRONT...DECREASING AFTER 06Z SUNDAY.


WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES
SNOW AND MVFR/IFR CONDITIONS WILL INCREASE VCNTY AND NORTH OF A
KEMM-KPNA LINE 09Z-14Z WITH THESE CONDITIONS BECOMING WIDESPREAD
AFTER 14Z. LLWS WILL ALSO INCREASE ACROSS THE AREA EARLY THIS
MORNING AS FL075-100 WINDS INCREASE TO BTWN 35-50KTS.  A STRONG COLD
FRONT WILL PUSH ACROSS THE AREA SATURDAY AFTERNOON BRINGING
WIDESPREAD IFR...AREAS OF LIFR CONDITIONS IN SN/BLSN ALONG...AREAS
OF WEST SFC WIND 20-30KTS WITH GUSTS TO 40KTS.  SNOW AND WIND WILL
DECREASE AFTER 02Z SUNDAY BEHIND THE FRONT WITH NMRS SHSN LINGERING
OVER THE MOUNTAINS AND MAINLY SCT SHSN OVER THE VALLEYS WITH SOME
MORE ORGANIZED BANDING POSSIBLE...ESPECIALLY VCNTY KJAC-KAFO.

&&

.FIRE WEATHER...

A SIGNIFICANT WINTER WEATHER SYSTEM WILL BEGIN IMPACTING WESTERN
WYOMING THIS EVENING...AND SNOWFALL SPREADING TO INCLUDE MUCH OF
THE FORECAST AREA BY SATURDAY AFTERNOON. WINTER WEATHER HIGHLIGHTS
AREA IN EFFECT. ADDITIONALLY...STRONG WIND WILL DEVELOP ACROSS THE
WIND CORRIDOR BETWEEN ROCK SPRINGS AND CASPER...AND WILL ALSO
DEVELOP IN THE CODY FOOTHILLS. HIGH WIND WARNINGS ARE IN EFFECT
FOR MUCH OF THE DAY SATURDAY FOR THESE LOCATIONS. FIRE WEATHER
BEHAVIOR IS EXPECTED TO REMAIN MINIMAL UNDER THIS SYSTEM...WITH
THE BEST DISPERSION RATES OCCURRING DURING THE STORM. PLEASE SEE
THE APPROPRIATE WEATHER HIGHLIGHT PRODUCT FOR ADDITIONAL
INFORMATION REGARDING THE WINTER STORM AND HIGH WIND
WARNINGS...AND THE WINTER WEATHER ADVISORY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM 6 AM SATURDAY TO MIDNIGHT MST SATURDAY
NIGHT WYZ003-019-020-022.

WINTER WEATHER ADVISORY FROM 3 AM SATURDAY TO 6 AM MST SUNDAY
WYZ016-026-027.

WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 AM MST SUNDAY
WYZ001-002-012>015-023>025.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...LIPSON
AVIATION...AEM
FIRE WEATHER...BRANHAM











000
FXUS63 KUNR 220510
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1010 PM MST FRI NOV 21 2014

.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 251 PM MST FRI NOV 21 2014

MILD CONDITIONS WILL CONTINUE THROUGH SATURDAY AS DRY
WESTERLY PAC FLOW REMAINS IN PLACE. WEAK MID LEVEL IMPULSE IS
CURRENTLY MOVING THROUGH THE REGION...SUPPORTING A SFC TROUGH INTO
THE AREA. THIS SYSTEM WILL SUPPORT LITTLE TO NO CAA...KEEPING
THERMAL FIELDS BASICALLY UNALTERED ON IT/S BACKSIDE. ATTENTION TURNS
TOWARD A STRONG MID LEVEL TROUGH NOW ENTERING THE PAC NW. THIS
SYSTEM WILL CROSS THE NORTHERN ROCKIES AND AMPLIFY PER A STAUNCH
150+ KNOT UPPER LEVEL JET...ENTERING THE NORTHERN PLAINS LATER
SATURDAY. THIS SYSTEM WILL SUPPORT STRONG LL PRESSURE
FALLS...AND A DEEPENING SFC CYCLONE OVER THE REGION BY SAT
NIGHT. THIS SYSTEM WILL QUICKLY PROGRESS THROUGH THE REGION SAT
NIGHT...SUPPORTING FRONTOGENETIC FORCING AND RESULTING RAIN AND
SNOW...ESP OVER NE WY AND THE NORTHERN HILLS. ANY SHOWERS WILL
LIKELY START AS RAIN OR A RAIN SNOW/MIX...WITH PRECIP TYPE
TRANSITIONING TO ALL SNOW SAT NIGHT. OVERALL...PRECIP CHANCES
REMAIN IN THE SCT-ISOLD RANGE...GIVEN LACK OF SIG FOCUS UVM. ANY
SNOW ACCUMS ARE EXPECTED TO BE AN INCH OR LESS...OUTSIDE OF THE
NORTHERN HILLS WHERE A COUPLE INCHES WILL BE POSSIBLE.

AS FOR TEMPS...PAC NW SYSTEM WILL SUPPORT RE-NEWED DOWNSTREAM
RIDGING WITH AN ASSOCIATED THERMAL RIDGE...WHICH WILL ADVECT OVER
THE REGION SAT. GIVEN CYCLOGENESIS AND INCREASED SFC PRESSURE
FALLS...WESTERLY WINDS WILL INCREASE OVER THE REGION
SAT...SUPPORTING GOOD MIXING. THIS WILL ALLOW ANOTHER WARM DAY
ACROSS THE AREA...WITH 40S AND 50S COMMON ESP...WARMEST ACROSS THE
EASTERN BLACK HILLS AND SCENTRAL SD. WINDS WILL INCREASE SAT EVE
AHEAD OF THE SFC TROUGH IN THE FAVORED DOWNSLOPE AREAS ACROSS THE
BLACK HILLS...WITH WINDS INCREASING EVERYWHERE ACROSS THE REGION
LATE SAT NIGHT...POST FRONTAL. STRONG NW WINDS WILL DEVELOP AS
STAUNCH CAA COMBINES WITH SFC PRESSURE RISES AND INCREASING BL FLOW.
HAVE INCREASED WINDS SOME SAT NIGHT.

&&

.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 251 PM MST FRI NOV 21 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. A TIGHT PRESSURE GRADIENT ON THE BACKSIDE OF LOW PRESSURE
PUSHING INTO THE UPPER MIDWEST WILL BRING VERY WINDY CONDITIONS TO
MUCH OF THE WESTERN SD PLAINS ON SUNDAY. THERE IS POTENTIAL FOR
WARNING CRITERIA WINDS SUNDAY AFTERNOON ACROSS NORTHWEST AND WEST
CENTRAL SD. WILL LET NEXT SHIFT HAVE ANOTHER LOOK AND SEE IF A WATCH
IS NEEDED. UPSLOPE ENHANCED SNOW SHOWERS WILL MAINLY AFFECT THE
NORTHERN BLACK HILLS ON SUNDAY...WITH SOME LIGHT ACCUMULATIONS
LIKELY. WINDS WILL REMAIN BREEZY ON MONDAY. ADDITIONAL WEAK
DISTURBANCES IN NORTHWEST FLOW WILL BRING CLOUDS AND CHANCES FOR
SNOW SHOWERS AT TIMES THROUGH WEDNESDAY.

THERE IS STILL UNCERTAINTY TOWARD THE LATTER PART OF NEXT WEEK...BUT
LONGER RANGE MODELS ARE IN BETTER AGREEMENT RIGHT NOW FOR THE
THANKSGIVING PERIOD...WITH A MILDER AND DRIER STRETCH OF WEATHER
LOOKING MORE LIKELY. WILL GO WITH MILDER TEMPERATURES THURSDAY AND
FRIDAY...ESPECIALLY OVER WESTERN PORTIONS OF THE CWA. IF LATEST
TRENDS PERSIST...TEMPERATURES WILL BE NEAR OR ABOVE AVERAGE IN MOST
AREAS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1008 PM MST FRI NOV 21 2014

VFR CONDITIONS EXPECTED THROUGH SATURDAY AFTERNOON. BREEZY
SOUTHWEST WILL DEVELOP ACROSS NORTHEAST WY/HIGHER ELEVATIONS OF
THE BLACK HILLS OVERNIGHT. A COLD FRONT WILL SWEEP THROUGH
SATURDAY EVENING BRINGING A FEW -SHRASN AND LOCAL MVFR CIGS.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...JC
LONG TERM...26
AVIATION...HELGESON




000
FXUS63 KUNR 220510
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1010 PM MST FRI NOV 21 2014

.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 251 PM MST FRI NOV 21 2014

MILD CONDITIONS WILL CONTINUE THROUGH SATURDAY AS DRY
WESTERLY PAC FLOW REMAINS IN PLACE. WEAK MID LEVEL IMPULSE IS
CURRENTLY MOVING THROUGH THE REGION...SUPPORTING A SFC TROUGH INTO
THE AREA. THIS SYSTEM WILL SUPPORT LITTLE TO NO CAA...KEEPING
THERMAL FIELDS BASICALLY UNALTERED ON IT/S BACKSIDE. ATTENTION TURNS
TOWARD A STRONG MID LEVEL TROUGH NOW ENTERING THE PAC NW. THIS
SYSTEM WILL CROSS THE NORTHERN ROCKIES AND AMPLIFY PER A STAUNCH
150+ KNOT UPPER LEVEL JET...ENTERING THE NORTHERN PLAINS LATER
SATURDAY. THIS SYSTEM WILL SUPPORT STRONG LL PRESSURE
FALLS...AND A DEEPENING SFC CYCLONE OVER THE REGION BY SAT
NIGHT. THIS SYSTEM WILL QUICKLY PROGRESS THROUGH THE REGION SAT
NIGHT...SUPPORTING FRONTOGENETIC FORCING AND RESULTING RAIN AND
SNOW...ESP OVER NE WY AND THE NORTHERN HILLS. ANY SHOWERS WILL
LIKELY START AS RAIN OR A RAIN SNOW/MIX...WITH PRECIP TYPE
TRANSITIONING TO ALL SNOW SAT NIGHT. OVERALL...PRECIP CHANCES
REMAIN IN THE SCT-ISOLD RANGE...GIVEN LACK OF SIG FOCUS UVM. ANY
SNOW ACCUMS ARE EXPECTED TO BE AN INCH OR LESS...OUTSIDE OF THE
NORTHERN HILLS WHERE A COUPLE INCHES WILL BE POSSIBLE.

AS FOR TEMPS...PAC NW SYSTEM WILL SUPPORT RE-NEWED DOWNSTREAM
RIDGING WITH AN ASSOCIATED THERMAL RIDGE...WHICH WILL ADVECT OVER
THE REGION SAT. GIVEN CYCLOGENESIS AND INCREASED SFC PRESSURE
FALLS...WESTERLY WINDS WILL INCREASE OVER THE REGION
SAT...SUPPORTING GOOD MIXING. THIS WILL ALLOW ANOTHER WARM DAY
ACROSS THE AREA...WITH 40S AND 50S COMMON ESP...WARMEST ACROSS THE
EASTERN BLACK HILLS AND SCENTRAL SD. WINDS WILL INCREASE SAT EVE
AHEAD OF THE SFC TROUGH IN THE FAVORED DOWNSLOPE AREAS ACROSS THE
BLACK HILLS...WITH WINDS INCREASING EVERYWHERE ACROSS THE REGION
LATE SAT NIGHT...POST FRONTAL. STRONG NW WINDS WILL DEVELOP AS
STAUNCH CAA COMBINES WITH SFC PRESSURE RISES AND INCREASING BL FLOW.
HAVE INCREASED WINDS SOME SAT NIGHT.

&&

.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 251 PM MST FRI NOV 21 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. A TIGHT PRESSURE GRADIENT ON THE BACKSIDE OF LOW PRESSURE
PUSHING INTO THE UPPER MIDWEST WILL BRING VERY WINDY CONDITIONS TO
MUCH OF THE WESTERN SD PLAINS ON SUNDAY. THERE IS POTENTIAL FOR
WARNING CRITERIA WINDS SUNDAY AFTERNOON ACROSS NORTHWEST AND WEST
CENTRAL SD. WILL LET NEXT SHIFT HAVE ANOTHER LOOK AND SEE IF A WATCH
IS NEEDED. UPSLOPE ENHANCED SNOW SHOWERS WILL MAINLY AFFECT THE
NORTHERN BLACK HILLS ON SUNDAY...WITH SOME LIGHT ACCUMULATIONS
LIKELY. WINDS WILL REMAIN BREEZY ON MONDAY. ADDITIONAL WEAK
DISTURBANCES IN NORTHWEST FLOW WILL BRING CLOUDS AND CHANCES FOR
SNOW SHOWERS AT TIMES THROUGH WEDNESDAY.

THERE IS STILL UNCERTAINTY TOWARD THE LATTER PART OF NEXT WEEK...BUT
LONGER RANGE MODELS ARE IN BETTER AGREEMENT RIGHT NOW FOR THE
THANKSGIVING PERIOD...WITH A MILDER AND DRIER STRETCH OF WEATHER
LOOKING MORE LIKELY. WILL GO WITH MILDER TEMPERATURES THURSDAY AND
FRIDAY...ESPECIALLY OVER WESTERN PORTIONS OF THE CWA. IF LATEST
TRENDS PERSIST...TEMPERATURES WILL BE NEAR OR ABOVE AVERAGE IN MOST
AREAS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1008 PM MST FRI NOV 21 2014

VFR CONDITIONS EXPECTED THROUGH SATURDAY AFTERNOON. BREEZY
SOUTHWEST WILL DEVELOP ACROSS NORTHEAST WY/HIGHER ELEVATIONS OF
THE BLACK HILLS OVERNIGHT. A COLD FRONT WILL SWEEP THROUGH
SATURDAY EVENING BRINGING A FEW -SHRASN AND LOCAL MVFR CIGS.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...JC
LONG TERM...26
AVIATION...HELGESON





000
FXUS65 KCYS 220501
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
958 PM MST FRI NOV 21 2014

.UPDATE...
ISSUED AT 906 PM MST FRI NOV 21 2014

H25-H50 WIND/HEIGHT SHOWED THE LEADING EDGE OF 90KT JET MAXIMA
MOVING ACROSS ID/WESTERN MT...AND WILL PROGRESS EASTWARD INTO WY
OVERNIGHT. COUPLED WITH H70-H85 GEOPOTENTIAL HEIGHT GRADIENTS FROM
CRAIG-CASPER EXCEEDING 60M...EXPECT HIGH WIND CRITERIA TO BE MET
IN THE ARLINGTON/BORDEAUX AREAS BETWEEN 09Z AND 12Z SAT. MOIST
ENERGETIC FLOW STILL FORECAST TO AFFECT AREAS WEST OF THE LARAMIE
RANGE BEGINNING SAT AFTERNOON. NO CHANGES PLANNED TO THE HIGH
WIND/WINTER STORM HEADLINES THIS EVENING.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

QUIET WEATHER IS QUICKLY COMING TO AN END AS WE TRANSITION INTO A
VERY ACTIVE PATTERN FOR THE SHORT TERM PERIOD. HIGHLIGHTS REVOLVE
AROUND POTENTIAL FOR VERY STRONG WINDS OVER SOUTHEAST WYOMING AND
POSSIBLY WESTERN NEBRASKA...AND MOUNTAIN SNOWS. LATEST WATER VAPOR
SATELLITE LOOP SHOWS A VIGOROUS UPPER-LEVEL SHORTWAVE JUST ABOUT TO
CRASH INTO THE PACIFIC NORTHWEST THIS EVE. OBJECTIVE UPPER ANALYSIS
SHOWS A STRONG 110+ KT JET CORE OFFSHORE AT 21Z. THIS WILL BE OUR
MAJOR WEATHER MAKER OVER THE NEXT COUPLE OF DAYS AS THE SYSTEM MOVES
RAPIDLY SOUTHEAST AND STRENGTHENS. NOT EXPECTING ANYTHING MAJOR IN
THE NEAR TERM THOUGH. SHOULD BE A QUIET EVENING WITH WINDS STARTING
TO RELAX AS MIXING DWINDLES WITH THE LOSS OF AFTN HEATING. A BROAD
AREA OF SURFACE HIGH PRESSURE WILL KEEP THINGS ON THE DRY SIDE.

THINGS CHANGE QUICKLY INTO TONIGHT. THE NAM H85 CAG-CPR GRADIENT IS
PROGGED TO CLIMB ABOVE 60 METERS BY ABOUT 09Z SAT. MODELED LOW
LEVEL FLOW IS IMPRESSIVE TO SAY THE LEAST WITH AN EXTENSIVE CORE
OF 60 TO 70 KT WINDS BETWEEN 700 AND 800 MILLIBARS OVER A GOOD
CHUNK OF OUR WYOMING ZONES BY SUNRISE. WITH EXCELLENT SUBSIDENCE
OVER THE TRADITIONAL GAP AREAS AND GOOD 6-HR PRESSURE FALLS ON THE
ORDER OF 5-10 MB PER THE GFS...CONFIDENCE IS HIGH IN A WIDESPREAD
AND POTENTIALLY SIGNIFICANT WIND EVENT. WENT AHEAD AND UPGRADED TO
A HIGH WIND WARNING WITH ALL ZONES STARTING AT 09Z. ARL AND BRX
SHOULD HIT FIRST...WITH THE WIND CORE ALOFT SPREADING INTO THE
SOUTHERN LARAMIE RANGE/FOOTHILLS AT OR AROUND SUNRISE. ADDED THE
NORTHERN LARAMIE RANGE TO THE WARNING AS WELL AS BOTH THE GFS AND
NAM SHOW 65 KT WINDS AT H75 TO THE SOUTH OF DEER CREEK IN WESTERN
CONVERSE COUNTY. THIS MAY BE QUITE THE EVENT WITH MULTIPLE GUSTS
OVER 70 MPH. ANOTHER EVENTUAL CONCERN IS THE POTENTIAL FOR LIGHT
SNOW WEST OF THE LARAMIE RANGE LATER IN THE AFTERNOON AND EVENING.
WITH STRONG WINDS WILL COME THE POTENTIAL FOR SIGNIFICANTLY
REDUCED VISIBILITIES IN BLOWING SNOW EVEN THOUGH LOWER ELEVATIONS
SHOULD NOT SEE MUCH FOR ACCUMULATIONS. MADE IT A POINT TO MENTION
THIS IN THE NPW PRODUCT.

SOMEWHAT CONCERNED THAT SOME OF THE ADJACENT VALLEYS AND HIGH PLAINS
MAY GET IN ON SOME OF THE WINDY FUN TOMORROW AS WELL. THERE ARE SOME
KEY DIFFERENCES IN THE GFS AND NAM WHICH WILL HAVE A ROLE IN WHETHER
OR NOT WE SEE WARNING CRITERIA WINDS AT AREAS SUCH AS CHEYENNE AND
THE LARAMIE VALLEY. FORECAST SOUNDINGS FROM BOTH MODELS SHOW A BELT
OF VERY STRONG FLOW NOT FAR OFF THE SURFACE. THE DIFFERENCES ARE IN
THE MIXING. MAIN LIMITING FACTOR WILL BE CLOUD COVER...BUT BOTH THE
LOW AND MID LEVEL RH FIELDS DO NOT SUGGEST ANYTHING THICK ENOUGH.
COULD EVENTUALLY SEE AN ABUNDANCE OF LENTICULARS EAST OF THE
MOUNTAINS AS MOUNTAIN WAVE ACTIVITY BECOMES INTENSE IN THE AFTN.
IF THIS DOES NOT IMPACT SURFACE HEATING...GFS SOUNDINGS SUGGEST
50-60 KT AT THE TOP OF THE MIXED LAYER AT LARAMIE AND CHEYENNE.
THE NAM IS CONSIDERABLY LESS...HOWEVER IT DOES SHOW SUBSIDENCE IN
ITS OMEGA FIELDS SPREADING SLOWLY ONTO THE PLAINS BETWEEN 18-00Z.
DECIDED TO ISSUE A HIGH WIND WATCH FOR LOWER ELEVATIONS
IMMEDIATELY ADJACENT TO THE LARAMIE RANGE AND FOOTHILLS. EVEN IF
AFTERNOON MIXING IS NOT THE CULPRIT...MODELS ARE IN GOOD AGREEMENT
WITH A TRANSITION TO A BORA WIND EVENT ON SAT NIGHT THROUGH EARLY
SUN AS A COLD FRONT SWEEPS ACROSS THE CWA. COULD SEE WIND GUSTS
RAMP UP AGAIN FOR A FEW HOURS AROUND MIDNIGHT...WITH A FEW GUSTS
TO 60 MPH POSSIBLE OVERNIGHT.

SUNDAY WILL BE VERY WINDY OVER THE PLAINS OF SOUTHEAST WYOMING AND
THE WESTERN PANHANDLE. THE CWA WILL BE IN THE POST FRONTAL AIR MASS
AND THE MODELS SHOW A RIBBON OF 60 TO 70 KT FROM NEAR LUSK
SOUTHEAST TOWARD SIDNEY AT 00Z MON. WILL LIKELY NEED MORE WIND
HEADLINES FOR THIS TIME FRAME...BUT WILL GET THROUGH THE SATURDAY
EVENT FIRST. NOW THAT THE WIND DISCUSSION IS OUT THE WAY...ONTO
THE SNOW POTENTIAL. DIDN`T MAKE ANY CHANGES TO THE WINTER STORM
WATCH FOR THE MOUNTAINS...BUT IT STILL LOOKS GOOD. CONVEYOR BELT OF
AN UPPER JET WITH 150+ KT H25 CORE IS PROGGED TO REMAIN ANCHORED
OVER THE WESTERN US FOR SEVERAL DAYS WITH OUR MOUNTAINS REMAINING
IN THE FAVORED LEFT EXIT REGION. THIS COMBINED WITH FAVORABLE
OROGRAPHICS IN WEST-NORTHWEST FLOW AND AND SEVERAL REINFORCING
SHOTS OF 700-300 MILLIBAR MOISTURE EMBEDDED IN THE ACTIVE FLOW
ALOFT WILL SUPPORT PERIODS OF HEAVY SNOW. SHOULD SEE ONE OR TWO
FEET THROUGH MON WITH ADDITIONAL SNOW POSSIBLE IN THE DAYS
FOLLOWING. SHOULD BE PRIMARILY A MOUNTAIN EVENT WITH AREAS EAST OF
THE LARAMIE RANGE STAYING DRY IN DOWNSLOPING LOW LEVEL FLOW. MAY
SEE A FEW RAIN OR SNOW SHOWERS OVER THE NORTHERN PANHANDLE ON SUN
AFTN AS PVA OVERSPREADS THE AREA.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

BASED ON GFS/ECMWF MODEL SOLUTIONS...SHOULD SEE A BREAK IN SNOW
ACCUMULATIONS OVER SOUTHEAST WYOMING MOUNTAINS SUNDAY EVENING WITH
A SHORTWAVE RIDGE IN PLACE. THEN THE NEXT SHOT OF SNOW LIKELY TO
DEVELOP AFTER MIDNIGHT SUNDAY NIGHT. COULD SEE SOME LIGHT SNOW
INTO LOWER ELEVATIONS BUT MOST SNOW ACCUMULATIONS WILL GENERALLY
BE IN THE MOUNTAINS. VERY LITTLE CHANCE FOR ANY ACCUMULATIONS
EAST OF THE LARAMIE RANGE SUNDAY NIGHT THROUGH MONDAY. WINDS WILL
SUBSIDE ACROSS MOST OF THE AREA SUNDAY NIGHT BUT ANOTHER PUSH OF
STRONGER WINDS POSSIBLE MONDAY NIGHT AS ANOTHER STRONG UPPER LEVEL
JET MOVES OVER THE AREA. MAIN CONCERN FOR HIGH WINDS WILL BE OVER
THE FAVORED WIND PRONE LOCATIONS IN SOUTHEAST WYOMING SUCH AS
ARLINGTON...BORDEAUX AND THE SOUTHERN LARAMIE RANGE.

THE NEXT QUICK MOVING CLIPPER SYSTEM ALONG WITH THE UPPER JET
WILL BRING A CHANCE FOR LIGHT SNOW SHOWERS THROUGH TUESDAY
AFTERNOON...INCLUDING INTO THE NEBRASKA PANHANDLE. AT THIS TIME
NOT EXPECTING MUCH IN THE WAY OF SNOW ACCUMULATIONS...IF ANY. MAINLY
LOOKING FOR LIGHT SNOW SHOWERS AND FLURRIES.

UNCERTAINTY REMAINS FOR LATER PORTIONS OF THE WEEK AND HOLIDAY
WEEKEND GIVEN THE GFS AND ECMWF WERE COMPLETELY DIFFERENT IN
THEIR SOLUTIONS YESTERDAY. HOWEVER...BOTH MODELS TRENDED TOWARD
EACH OTHER TODAY AND HAVE RATHER SIMILAR SOLUTIONS. WOULD LIKE TO
SEE RUN OR TWO OF CONSISTENCY BUT BASED ON LATEST SOLUTIONS IT
WOULD WARM BOTH THURSDAY AND FRIDAY WITH A FLATTENING RIDGE OVER
THE NORTHERN ROCKIES PRODUCING DOWNSLOPE WARMING. INTO THE WEEKEND
THE MODELS SUGGEST A FAST MOVING BUT RELATIVELY WEAK WAVE MOVING
ACROSS THE AREA...SO NO BIG HAZARDOUS WEATHER THREAT EXPECTED AT
THIS TIME.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1000 PM MST FRI NOV 21 2014

PRIMARY AVIATION CONCERNS WILL FOCUS ON STRONG WINDS OVERNIGHT
TONIGHT THROUGH SATURDAY NIGHT...WITH ACCUMULATING SNOW DEVELOPING
OVER THE MOUNTAINS SATURDAY AFTERNOON. FREQUENT GUSTS TO 50 KT AND
HIGHER WILL DEVELOP IN THE ARLINGTON AND BORDEAUX AREAS BETWEEN
09Z AND 12Z TONIGHT. THESE STRONG WEST TO SOUTHWEST WINDS WILL
THEN SPREAD INTO THE SOUTHERN AND NORTHERN LARAMIE RANGES SATURDAY
MORNING. GUSTY WINDS WILL ALSO SPREAD INTO LOWER ELEVATIONS AND
INTO THE PLAINS OF SOUTHEAST WYOMING SATURDAY AFTERNOON WITH GUSTS
OF 30 TO 40 KT COMMON. WINDS WILL NOT BE AS STRONG ACROSS THE
WESTERN NEBRASKA PANHANDLE BUT STILL BREEZY. THE MOUNTAINS WILL BE
OBSCURED DUE TO FALLING AND BLOWING SNOW SATURDAY AFTERNOON AND
EVENING. PREVAILING MVFR CEILINGS/VISIBIITIES WERE INTRODUCED AT
RAWLINS BEGINNING LATE SATURDAY AFTERNOON WITH DEVELOPING LIGHT
RAIN/SNOW.

&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WARNING FROM 2 AM SATURDAY TO 5 AM MST SUNDAY FOR
     WYZ103>106-110-116-117.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH LATE SATURDAY
     NIGHT FOR WYZ101-107-115-118.

NE...NONE.
&&

$$

UPDATE...MJ
SHORT TERM...CLH
LONG TERM...SML
AVIATION...MJ
FIRE WEATHER...RJM



000
FXUS65 KCYS 220501
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
958 PM MST FRI NOV 21 2014

.UPDATE...
ISSUED AT 906 PM MST FRI NOV 21 2014

H25-H50 WIND/HEIGHT SHOWED THE LEADING EDGE OF 90KT JET MAXIMA
MOVING ACROSS ID/WESTERN MT...AND WILL PROGRESS EASTWARD INTO WY
OVERNIGHT. COUPLED WITH H70-H85 GEOPOTENTIAL HEIGHT GRADIENTS FROM
CRAIG-CASPER EXCEEDING 60M...EXPECT HIGH WIND CRITERIA TO BE MET
IN THE ARLINGTON/BORDEAUX AREAS BETWEEN 09Z AND 12Z SAT. MOIST
ENERGETIC FLOW STILL FORECAST TO AFFECT AREAS WEST OF THE LARAMIE
RANGE BEGINNING SAT AFTERNOON. NO CHANGES PLANNED TO THE HIGH
WIND/WINTER STORM HEADLINES THIS EVENING.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

QUIET WEATHER IS QUICKLY COMING TO AN END AS WE TRANSITION INTO A
VERY ACTIVE PATTERN FOR THE SHORT TERM PERIOD. HIGHLIGHTS REVOLVE
AROUND POTENTIAL FOR VERY STRONG WINDS OVER SOUTHEAST WYOMING AND
POSSIBLY WESTERN NEBRASKA...AND MOUNTAIN SNOWS. LATEST WATER VAPOR
SATELLITE LOOP SHOWS A VIGOROUS UPPER-LEVEL SHORTWAVE JUST ABOUT TO
CRASH INTO THE PACIFIC NORTHWEST THIS EVE. OBJECTIVE UPPER ANALYSIS
SHOWS A STRONG 110+ KT JET CORE OFFSHORE AT 21Z. THIS WILL BE OUR
MAJOR WEATHER MAKER OVER THE NEXT COUPLE OF DAYS AS THE SYSTEM MOVES
RAPIDLY SOUTHEAST AND STRENGTHENS. NOT EXPECTING ANYTHING MAJOR IN
THE NEAR TERM THOUGH. SHOULD BE A QUIET EVENING WITH WINDS STARTING
TO RELAX AS MIXING DWINDLES WITH THE LOSS OF AFTN HEATING. A BROAD
AREA OF SURFACE HIGH PRESSURE WILL KEEP THINGS ON THE DRY SIDE.

THINGS CHANGE QUICKLY INTO TONIGHT. THE NAM H85 CAG-CPR GRADIENT IS
PROGGED TO CLIMB ABOVE 60 METERS BY ABOUT 09Z SAT. MODELED LOW
LEVEL FLOW IS IMPRESSIVE TO SAY THE LEAST WITH AN EXTENSIVE CORE
OF 60 TO 70 KT WINDS BETWEEN 700 AND 800 MILLIBARS OVER A GOOD
CHUNK OF OUR WYOMING ZONES BY SUNRISE. WITH EXCELLENT SUBSIDENCE
OVER THE TRADITIONAL GAP AREAS AND GOOD 6-HR PRESSURE FALLS ON THE
ORDER OF 5-10 MB PER THE GFS...CONFIDENCE IS HIGH IN A WIDESPREAD
AND POTENTIALLY SIGNIFICANT WIND EVENT. WENT AHEAD AND UPGRADED TO
A HIGH WIND WARNING WITH ALL ZONES STARTING AT 09Z. ARL AND BRX
SHOULD HIT FIRST...WITH THE WIND CORE ALOFT SPREADING INTO THE
SOUTHERN LARAMIE RANGE/FOOTHILLS AT OR AROUND SUNRISE. ADDED THE
NORTHERN LARAMIE RANGE TO THE WARNING AS WELL AS BOTH THE GFS AND
NAM SHOW 65 KT WINDS AT H75 TO THE SOUTH OF DEER CREEK IN WESTERN
CONVERSE COUNTY. THIS MAY BE QUITE THE EVENT WITH MULTIPLE GUSTS
OVER 70 MPH. ANOTHER EVENTUAL CONCERN IS THE POTENTIAL FOR LIGHT
SNOW WEST OF THE LARAMIE RANGE LATER IN THE AFTERNOON AND EVENING.
WITH STRONG WINDS WILL COME THE POTENTIAL FOR SIGNIFICANTLY
REDUCED VISIBILITIES IN BLOWING SNOW EVEN THOUGH LOWER ELEVATIONS
SHOULD NOT SEE MUCH FOR ACCUMULATIONS. MADE IT A POINT TO MENTION
THIS IN THE NPW PRODUCT.

SOMEWHAT CONCERNED THAT SOME OF THE ADJACENT VALLEYS AND HIGH PLAINS
MAY GET IN ON SOME OF THE WINDY FUN TOMORROW AS WELL. THERE ARE SOME
KEY DIFFERENCES IN THE GFS AND NAM WHICH WILL HAVE A ROLE IN WHETHER
OR NOT WE SEE WARNING CRITERIA WINDS AT AREAS SUCH AS CHEYENNE AND
THE LARAMIE VALLEY. FORECAST SOUNDINGS FROM BOTH MODELS SHOW A BELT
OF VERY STRONG FLOW NOT FAR OFF THE SURFACE. THE DIFFERENCES ARE IN
THE MIXING. MAIN LIMITING FACTOR WILL BE CLOUD COVER...BUT BOTH THE
LOW AND MID LEVEL RH FIELDS DO NOT SUGGEST ANYTHING THICK ENOUGH.
COULD EVENTUALLY SEE AN ABUNDANCE OF LENTICULARS EAST OF THE
MOUNTAINS AS MOUNTAIN WAVE ACTIVITY BECOMES INTENSE IN THE AFTN.
IF THIS DOES NOT IMPACT SURFACE HEATING...GFS SOUNDINGS SUGGEST
50-60 KT AT THE TOP OF THE MIXED LAYER AT LARAMIE AND CHEYENNE.
THE NAM IS CONSIDERABLY LESS...HOWEVER IT DOES SHOW SUBSIDENCE IN
ITS OMEGA FIELDS SPREADING SLOWLY ONTO THE PLAINS BETWEEN 18-00Z.
DECIDED TO ISSUE A HIGH WIND WATCH FOR LOWER ELEVATIONS
IMMEDIATELY ADJACENT TO THE LARAMIE RANGE AND FOOTHILLS. EVEN IF
AFTERNOON MIXING IS NOT THE CULPRIT...MODELS ARE IN GOOD AGREEMENT
WITH A TRANSITION TO A BORA WIND EVENT ON SAT NIGHT THROUGH EARLY
SUN AS A COLD FRONT SWEEPS ACROSS THE CWA. COULD SEE WIND GUSTS
RAMP UP AGAIN FOR A FEW HOURS AROUND MIDNIGHT...WITH A FEW GUSTS
TO 60 MPH POSSIBLE OVERNIGHT.

SUNDAY WILL BE VERY WINDY OVER THE PLAINS OF SOUTHEAST WYOMING AND
THE WESTERN PANHANDLE. THE CWA WILL BE IN THE POST FRONTAL AIR MASS
AND THE MODELS SHOW A RIBBON OF 60 TO 70 KT FROM NEAR LUSK
SOUTHEAST TOWARD SIDNEY AT 00Z MON. WILL LIKELY NEED MORE WIND
HEADLINES FOR THIS TIME FRAME...BUT WILL GET THROUGH THE SATURDAY
EVENT FIRST. NOW THAT THE WIND DISCUSSION IS OUT THE WAY...ONTO
THE SNOW POTENTIAL. DIDN`T MAKE ANY CHANGES TO THE WINTER STORM
WATCH FOR THE MOUNTAINS...BUT IT STILL LOOKS GOOD. CONVEYOR BELT OF
AN UPPER JET WITH 150+ KT H25 CORE IS PROGGED TO REMAIN ANCHORED
OVER THE WESTERN US FOR SEVERAL DAYS WITH OUR MOUNTAINS REMAINING
IN THE FAVORED LEFT EXIT REGION. THIS COMBINED WITH FAVORABLE
OROGRAPHICS IN WEST-NORTHWEST FLOW AND AND SEVERAL REINFORCING
SHOTS OF 700-300 MILLIBAR MOISTURE EMBEDDED IN THE ACTIVE FLOW
ALOFT WILL SUPPORT PERIODS OF HEAVY SNOW. SHOULD SEE ONE OR TWO
FEET THROUGH MON WITH ADDITIONAL SNOW POSSIBLE IN THE DAYS
FOLLOWING. SHOULD BE PRIMARILY A MOUNTAIN EVENT WITH AREAS EAST OF
THE LARAMIE RANGE STAYING DRY IN DOWNSLOPING LOW LEVEL FLOW. MAY
SEE A FEW RAIN OR SNOW SHOWERS OVER THE NORTHERN PANHANDLE ON SUN
AFTN AS PVA OVERSPREADS THE AREA.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

BASED ON GFS/ECMWF MODEL SOLUTIONS...SHOULD SEE A BREAK IN SNOW
ACCUMULATIONS OVER SOUTHEAST WYOMING MOUNTAINS SUNDAY EVENING WITH
A SHORTWAVE RIDGE IN PLACE. THEN THE NEXT SHOT OF SNOW LIKELY TO
DEVELOP AFTER MIDNIGHT SUNDAY NIGHT. COULD SEE SOME LIGHT SNOW
INTO LOWER ELEVATIONS BUT MOST SNOW ACCUMULATIONS WILL GENERALLY
BE IN THE MOUNTAINS. VERY LITTLE CHANCE FOR ANY ACCUMULATIONS
EAST OF THE LARAMIE RANGE SUNDAY NIGHT THROUGH MONDAY. WINDS WILL
SUBSIDE ACROSS MOST OF THE AREA SUNDAY NIGHT BUT ANOTHER PUSH OF
STRONGER WINDS POSSIBLE MONDAY NIGHT AS ANOTHER STRONG UPPER LEVEL
JET MOVES OVER THE AREA. MAIN CONCERN FOR HIGH WINDS WILL BE OVER
THE FAVORED WIND PRONE LOCATIONS IN SOUTHEAST WYOMING SUCH AS
ARLINGTON...BORDEAUX AND THE SOUTHERN LARAMIE RANGE.

THE NEXT QUICK MOVING CLIPPER SYSTEM ALONG WITH THE UPPER JET
WILL BRING A CHANCE FOR LIGHT SNOW SHOWERS THROUGH TUESDAY
AFTERNOON...INCLUDING INTO THE NEBRASKA PANHANDLE. AT THIS TIME
NOT EXPECTING MUCH IN THE WAY OF SNOW ACCUMULATIONS...IF ANY. MAINLY
LOOKING FOR LIGHT SNOW SHOWERS AND FLURRIES.

UNCERTAINTY REMAINS FOR LATER PORTIONS OF THE WEEK AND HOLIDAY
WEEKEND GIVEN THE GFS AND ECMWF WERE COMPLETELY DIFFERENT IN
THEIR SOLUTIONS YESTERDAY. HOWEVER...BOTH MODELS TRENDED TOWARD
EACH OTHER TODAY AND HAVE RATHER SIMILAR SOLUTIONS. WOULD LIKE TO
SEE RUN OR TWO OF CONSISTENCY BUT BASED ON LATEST SOLUTIONS IT
WOULD WARM BOTH THURSDAY AND FRIDAY WITH A FLATTENING RIDGE OVER
THE NORTHERN ROCKIES PRODUCING DOWNSLOPE WARMING. INTO THE WEEKEND
THE MODELS SUGGEST A FAST MOVING BUT RELATIVELY WEAK WAVE MOVING
ACROSS THE AREA...SO NO BIG HAZARDOUS WEATHER THREAT EXPECTED AT
THIS TIME.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1000 PM MST FRI NOV 21 2014

PRIMARY AVIATION CONCERNS WILL FOCUS ON STRONG WINDS OVERNIGHT
TONIGHT THROUGH SATURDAY NIGHT...WITH ACCUMULATING SNOW DEVELOPING
OVER THE MOUNTAINS SATURDAY AFTERNOON. FREQUENT GUSTS TO 50 KT AND
HIGHER WILL DEVELOP IN THE ARLINGTON AND BORDEAUX AREAS BETWEEN
09Z AND 12Z TONIGHT. THESE STRONG WEST TO SOUTHWEST WINDS WILL
THEN SPREAD INTO THE SOUTHERN AND NORTHERN LARAMIE RANGES SATURDAY
MORNING. GUSTY WINDS WILL ALSO SPREAD INTO LOWER ELEVATIONS AND
INTO THE PLAINS OF SOUTHEAST WYOMING SATURDAY AFTERNOON WITH GUSTS
OF 30 TO 40 KT COMMON. WINDS WILL NOT BE AS STRONG ACROSS THE
WESTERN NEBRASKA PANHANDLE BUT STILL BREEZY. THE MOUNTAINS WILL BE
OBSCURED DUE TO FALLING AND BLOWING SNOW SATURDAY AFTERNOON AND
EVENING. PREVAILING MVFR CEILINGS/VISIBIITIES WERE INTRODUCED AT
RAWLINS BEGINNING LATE SATURDAY AFTERNOON WITH DEVELOPING LIGHT
RAIN/SNOW.

&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WARNING FROM 2 AM SATURDAY TO 5 AM MST SUNDAY FOR
     WYZ103>106-110-116-117.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH LATE SATURDAY
     NIGHT FOR WYZ101-107-115-118.

NE...NONE.
&&

$$

UPDATE...MJ
SHORT TERM...CLH
LONG TERM...SML
AVIATION...MJ
FIRE WEATHER...RJM




000
FXUS65 KCYS 220458
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
958 PM MST FRI NOV 21 2014

.UPDATE...
ISSUED AT 906 PM MST FRI NOV 21 2014

H25-H50 WIND/HEIGHT SHOWED THE LEADING EDGE OF 90KT JET MAXIMA
MOVING ACROSS ID/WESTERN MT...AND WILL PROGRESS EASTWARD INTO WY
OVERNIGHT. COUPLED WITH H70-H85 GEOPOTENTIAL HEIGHT GRADIENTS FROM
CRAIG-CASPER EXCEEDING 60M...EXPECT HIGH WIND CRITERIA TO BE MET
IN THE ARLINGTON/BORDEAUX AREAS BETWEEN 09Z AND 12Z SAT. MOIST
ENERGETIC FLOW STILL FORECAST TO AFFECT AREAS WEST OF THE LARAMIE
RANGE BEGINNING SAT AFTERNOON. NO CHANGES PLANNED TO THE HIGH
WIND/WINTER STORM HEADLINES THIS EVENING.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

QUIET WEATHER IS QUICKLY COMING TO AN END AS WE TRANSITION INTO A
VERY ACTIVE PATTERN FOR THE SHORT TERM PERIOD. HIGHLIGHTS REVOLVE
AROUND POTENTIAL FOR VERY STRONG WINDS OVER SOUTHEAST WYOMING AND
POSSIBLY WESTERN NEBRASKA...AND MOUNTAIN SNOWS. LATEST WATER VAPOR
SATELLITE LOOP SHOWS A VIGOROUS UPPER-LEVEL SHORTWAVE JUST ABOUT TO
CRASH INTO THE PACIFIC NORTHWEST THIS EVE. OBJECTIVE UPPER ANALYSIS
SHOWS A STRONG 110+ KT JET CORE OFFSHORE AT 21Z. THIS WILL BE OUR
MAJOR WEATHER MAKER OVER THE NEXT COUPLE OF DAYS AS THE SYSTEM MOVES
RAPIDLY SOUTHEAST AND STRENGTHENS. NOT EXPECTING ANYTHING MAJOR IN
THE NEAR TERM THOUGH. SHOULD BE A QUIET EVENING WITH WINDS STARTING
TO RELAX AS MIXING DWINDLES WITH THE LOSS OF AFTN HEATING. A BROAD
AREA OF SURFACE HIGH PRESSURE WILL KEEP THINGS ON THE DRY SIDE.

THINGS CHANGE QUICKLY INTO TONIGHT. THE NAM H85 CAG-CPR GRADIENT IS
PROGGED TO CLIMB ABOVE 60 METERS BY ABOUT 09Z SAT. MODELED LOW
LEVEL FLOW IS IMPRESSIVE TO SAY THE LEAST WITH AN EXTENSIVE CORE
OF 60 TO 70 KT WINDS BETWEEN 700 AND 800 MILLIBARS OVER A GOOD
CHUNK OF OUR WYOMING ZONES BY SUNRISE. WITH EXCELLENT SUBSIDENCE
OVER THE TRADITIONAL GAP AREAS AND GOOD 6-HR PRESSURE FALLS ON THE
ORDER OF 5-10 MB PER THE GFS...CONFIDENCE IS HIGH IN A WIDESPREAD
AND POTENTIALLY SIGNIFICANT WIND EVENT. WENT AHEAD AND UPGRADED TO
A HIGH WIND WARNING WITH ALL ZONES STARTING AT 09Z. ARL AND BRX
SHOULD HIT FIRST...WITH THE WIND CORE ALOFT SPREADING INTO THE
SOUTHERN LARAMIE RANGE/FOOTHILLS AT OR AROUND SUNRISE. ADDED THE
NORTHERN LARAMIE RANGE TO THE WARNING AS WELL AS BOTH THE GFS AND
NAM SHOW 65 KT WINDS AT H75 TO THE SOUTH OF DEER CREEK IN WESTERN
CONVERSE COUNTY. THIS MAY BE QUITE THE EVENT WITH MULTIPLE GUSTS
OVER 70 MPH. ANOTHER EVENTUAL CONCERN IS THE POTENTIAL FOR LIGHT
SNOW WEST OF THE LARAMIE RANGE LATER IN THE AFTERNOON AND EVENING.
WITH STRONG WINDS WILL COME THE POTENTIAL FOR SIGNIFICANTLY
REDUCED VISIBILITIES IN BLOWING SNOW EVEN THOUGH LOWER ELEVATIONS
SHOULD NOT SEE MUCH FOR ACCUMULATIONS. MADE IT A POINT TO MENTION
THIS IN THE NPW PRODUCT.

SOMEWHAT CONCERNED THAT SOME OF THE ADJACENT VALLEYS AND HIGH PLAINS
MAY GET IN ON SOME OF THE WINDY FUN TOMORROW AS WELL. THERE ARE SOME
KEY DIFFERENCES IN THE GFS AND NAM WHICH WILL HAVE A ROLE IN WHETHER
OR NOT WE SEE WARNING CRITERIA WINDS AT AREAS SUCH AS CHEYENNE AND
THE LARAMIE VALLEY. FORECAST SOUNDINGS FROM BOTH MODELS SHOW A BELT
OF VERY STRONG FLOW NOT FAR OFF THE SURFACE. THE DIFFERENCES ARE IN
THE MIXING. MAIN LIMITING FACTOR WILL BE CLOUD COVER...BUT BOTH THE
LOW AND MID LEVEL RH FIELDS DO NOT SUGGEST ANYTHING THICK ENOUGH.
COULD EVENTUALLY SEE AN ABUNDANCE OF LENTICULARS EAST OF THE
MOUNTAINS AS MOUNTAIN WAVE ACTIVITY BECOMES INTENSE IN THE AFTN.
IF THIS DOES NOT IMPACT SURFACE HEATING...GFS SOUNDINGS SUGGEST
50-60 KT AT THE TOP OF THE MIXED LAYER AT LARAMIE AND CHEYENNE.
THE NAM IS CONSIDERABLY LESS...HOWEVER IT DOES SHOW SUBSIDENCE IN
ITS OMEGA FIELDS SPREADING SLOWLY ONTO THE PLAINS BETWEEN 18-00Z.
DECIDED TO ISSUE A HIGH WIND WATCH FOR LOWER ELEVATIONS
IMMEDIATELY ADJACENT TO THE LARAMIE RANGE AND FOOTHILLS. EVEN IF
AFTERNOON MIXING IS NOT THE CULPRIT...MODELS ARE IN GOOD AGREEMENT
WITH A TRANSITION TO A BORA WIND EVENT ON SAT NIGHT THROUGH EARLY
SUN AS A COLD FRONT SWEEPS ACROSS THE CWA. COULD SEE WIND GUSTS
RAMP UP AGAIN FOR A FEW HOURS AROUND MIDNIGHT...WITH A FEW GUSTS
TO 60 MPH POSSIBLE OVERNIGHT.

SUNDAY WILL BE VERY WINDY OVER THE PLAINS OF SOUTHEAST WYOMING AND
THE WESTERN PANHANDLE. THE CWA WILL BE IN THE POST FRONTAL AIR MASS
AND THE MODELS SHOW A RIBBON OF 60 TO 70 KT FROM NEAR LUSK
SOUTHEAST TOWARD SIDNEY AT 00Z MON. WILL LIKELY NEED MORE WIND
HEADLINES FOR THIS TIME FRAME...BUT WILL GET THROUGH THE SATURDAY
EVENT FIRST. NOW THAT THE WIND DISCUSSION IS OUT THE WAY...ONTO
THE SNOW POTENTIAL. DIDN`T MAKE ANY CHANGES TO THE WINTER STORM
WATCH FOR THE MOUNTAINS...BUT IT STILL LOOKS GOOD. CONVEYOR BELT OF
AN UPPER JET WITH 150+ KT H25 CORE IS PROGGED TO REMAIN ANCHORED
OVER THE WESTERN US FOR SEVERAL DAYS WITH OUR MOUNTAINS REMAINING
IN THE FAVORED LEFT EXIT REGION. THIS COMBINED WITH FAVORABLE
OROGRAPHICS IN WEST-NORTHWEST FLOW AND AND SEVERAL REINFORCING
SHOTS OF 700-300 MILLIBAR MOISTURE EMBEDDED IN THE ACTIVE FLOW
ALOFT WILL SUPPORT PERIODS OF HEAVY SNOW. SHOULD SEE ONE OR TWO
FEET THROUGH MON WITH ADDITIONAL SNOW POSSIBLE IN THE DAYS
FOLLOWING. SHOULD BE PRIMARILY A MOUNTAIN EVENT WITH AREAS EAST OF
THE LARAMIE RANGE STAYING DRY IN DOWNSLOPING LOW LEVEL FLOW. MAY
SEE A FEW RAIN OR SNOW SHOWERS OVER THE NORTHERN PANHANDLE ON SUN
AFTN AS PVA OVERSPREADS THE AREA.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

BASED ON GFS/ECMWF MODEL SOLUTIONS...SHOULD SEE A BREAK IN SNOW
ACCUMULATIONS OVER SOUTHEAST WYOMING MOUNTAINS SUNDAY EVENING WITH
A SHORTWAVE RIDGE IN PLACE. THEN THE NEXT SHOT OF SNOW LIKELY TO
DEVELOP AFTER MIDNIGHT SUNDAY NIGHT. COULD SEE SOME LIGHT SNOW
INTO LOWER ELEVATIONS BUT MOST SNOW ACCUMULATIONS WILL GENERALLY
BE IN THE MOUNTAINS. VERY LITTLE CHANCE FOR ANY ACCUMULATIONS
EAST OF THE LARAMIE RANGE SUNDAY NIGHT THROUGH MONDAY. WINDS WILL
SUBSIDE ACROSS MOST OF THE AREA SUNDAY NIGHT BUT ANOTHER PUSH OF
STRONGER WINDS POSSIBLE MONDAY NIGHT AS ANOTHER STRONG UPPER LEVEL
JET MOVES OVER THE AREA. MAIN CONCERN FOR HIGH WINDS WILL BE OVER
THE FAVORED WIND PRONE LOCATIONS IN SOUTHEAST WYOMING SUCH AS
ARLINGTON...BORDEAUX AND THE SOUTHERN LARAMIE RANGE.

THE NEXT QUICK MOVING CLIPPER SYSTEM ALONG WITH THE UPPER JET
WILL BRING A CHANCE FOR LIGHT SNOW SHOWERS THROUGH TUESDAY
AFTERNOON...INCLUDING INTO THE NEBRASKA PANHANDLE. AT THIS TIME
NOT EXPECTING MUCH IN THE WAY OF SNOW ACCUMULATIONS...IF ANY. MAINLY
LOOKING FOR LIGHT SNOW SHOWERS AND FLURRIES.

UNCERTAINTY REMAINS FOR LATER PORTIONS OF THE WEEK AND HOLIDAY
WEEKEND GIVEN THE GFS AND ECMWF WERE COMPLETELY DIFFERENT IN
THEIR SOLUTIONS YESTERDAY. HOWEVER...BOTH MODELS TRENDED TOWARD
EACH OTHER TODAY AND HAVE RATHER SIMILAR SOLUTIONS. WOULD LIKE TO
SEE RUN OR TWO OF CONSISTENCY BUT BASED ON LATEST SOLUTIONS IT
WOULD WARM BOTH THURSDAY AND FRIDAY WITH A FLATTENING RIDGE OVER
THE NORTHERN ROCKIES PRODUCING DOWNSLOPE WARMING. INTO THE WEEKEND
THE MODELS SUGGEST A FAST MOVING BUT RELATIVELY WEAK WAVE MOVING
ACROSS THE AREA...SO NO BIG HAZARDOUS WEATHER THREAT EXPECTED AT
THIS TIME.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1000 PM MST FRI NOV 21 2014

PRIMARY AVIATION CONCERNS WILL FOCUS ON STRONG WINDS OVERNIGHT
TONIGHT THROUGH SATURDAY NIGHT...WITH ACCUMULATING SNOW DEVELOPING
OVER THE MOUNTAINS SATURDAY AFTERNOON. FREQUENT GUSTS TO 50 KT AND
HIGHER WILL DEVELOP IN THE ARLINGTON AND BORDEAUX AREAS BETWEEN
09Z AND 12Z TONIGHT. THESE STRONG WEST TO SOUTHWEST WINDS WILL
THEN SPREAD INTO THE SOUTHERN AND NORTHERN LARAMIE RANGES SATURDAY
MORNING. GUSTY WINDS WILL ALSO SPREAD INTO LOWER ELEVATIONS AND
INTO THE PLAINS OF SOUTHEAST WYOMING SATURDAY AFTERNOON WITH GUSTS
OF 30 TO 40 KT COMMON. WINDS WILL NOT BE AS STRONG ACROSS THE
WESTERN NEBRASKA PANHANDLE BUT STILL BREEZY. THE MOUNTAINS WILL BE
OBSCURED DUE TO FALLING AND BLOWING SNOW SATURDAY AFTERNOON AND
EVENING.

&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WARNING FROM 2 AM SATURDAY TO 5 AM MST SUNDAY FOR
     WYZ103>106-110-116-117.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH LATE SATURDAY
     NIGHT FOR WYZ101-107-115-118.

NE...NONE.
&&

$$

UPDATE...MJ
SHORT TERM...CLH
LONG TERM...SML
AVIATION...MJ
FIRE WEATHER...RJM



000
FXUS65 KCYS 220458
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
958 PM MST FRI NOV 21 2014

.UPDATE...
ISSUED AT 906 PM MST FRI NOV 21 2014

H25-H50 WIND/HEIGHT SHOWED THE LEADING EDGE OF 90KT JET MAXIMA
MOVING ACROSS ID/WESTERN MT...AND WILL PROGRESS EASTWARD INTO WY
OVERNIGHT. COUPLED WITH H70-H85 GEOPOTENTIAL HEIGHT GRADIENTS FROM
CRAIG-CASPER EXCEEDING 60M...EXPECT HIGH WIND CRITERIA TO BE MET
IN THE ARLINGTON/BORDEAUX AREAS BETWEEN 09Z AND 12Z SAT. MOIST
ENERGETIC FLOW STILL FORECAST TO AFFECT AREAS WEST OF THE LARAMIE
RANGE BEGINNING SAT AFTERNOON. NO CHANGES PLANNED TO THE HIGH
WIND/WINTER STORM HEADLINES THIS EVENING.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

QUIET WEATHER IS QUICKLY COMING TO AN END AS WE TRANSITION INTO A
VERY ACTIVE PATTERN FOR THE SHORT TERM PERIOD. HIGHLIGHTS REVOLVE
AROUND POTENTIAL FOR VERY STRONG WINDS OVER SOUTHEAST WYOMING AND
POSSIBLY WESTERN NEBRASKA...AND MOUNTAIN SNOWS. LATEST WATER VAPOR
SATELLITE LOOP SHOWS A VIGOROUS UPPER-LEVEL SHORTWAVE JUST ABOUT TO
CRASH INTO THE PACIFIC NORTHWEST THIS EVE. OBJECTIVE UPPER ANALYSIS
SHOWS A STRONG 110+ KT JET CORE OFFSHORE AT 21Z. THIS WILL BE OUR
MAJOR WEATHER MAKER OVER THE NEXT COUPLE OF DAYS AS THE SYSTEM MOVES
RAPIDLY SOUTHEAST AND STRENGTHENS. NOT EXPECTING ANYTHING MAJOR IN
THE NEAR TERM THOUGH. SHOULD BE A QUIET EVENING WITH WINDS STARTING
TO RELAX AS MIXING DWINDLES WITH THE LOSS OF AFTN HEATING. A BROAD
AREA OF SURFACE HIGH PRESSURE WILL KEEP THINGS ON THE DRY SIDE.

THINGS CHANGE QUICKLY INTO TONIGHT. THE NAM H85 CAG-CPR GRADIENT IS
PROGGED TO CLIMB ABOVE 60 METERS BY ABOUT 09Z SAT. MODELED LOW
LEVEL FLOW IS IMPRESSIVE TO SAY THE LEAST WITH AN EXTENSIVE CORE
OF 60 TO 70 KT WINDS BETWEEN 700 AND 800 MILLIBARS OVER A GOOD
CHUNK OF OUR WYOMING ZONES BY SUNRISE. WITH EXCELLENT SUBSIDENCE
OVER THE TRADITIONAL GAP AREAS AND GOOD 6-HR PRESSURE FALLS ON THE
ORDER OF 5-10 MB PER THE GFS...CONFIDENCE IS HIGH IN A WIDESPREAD
AND POTENTIALLY SIGNIFICANT WIND EVENT. WENT AHEAD AND UPGRADED TO
A HIGH WIND WARNING WITH ALL ZONES STARTING AT 09Z. ARL AND BRX
SHOULD HIT FIRST...WITH THE WIND CORE ALOFT SPREADING INTO THE
SOUTHERN LARAMIE RANGE/FOOTHILLS AT OR AROUND SUNRISE. ADDED THE
NORTHERN LARAMIE RANGE TO THE WARNING AS WELL AS BOTH THE GFS AND
NAM SHOW 65 KT WINDS AT H75 TO THE SOUTH OF DEER CREEK IN WESTERN
CONVERSE COUNTY. THIS MAY BE QUITE THE EVENT WITH MULTIPLE GUSTS
OVER 70 MPH. ANOTHER EVENTUAL CONCERN IS THE POTENTIAL FOR LIGHT
SNOW WEST OF THE LARAMIE RANGE LATER IN THE AFTERNOON AND EVENING.
WITH STRONG WINDS WILL COME THE POTENTIAL FOR SIGNIFICANTLY
REDUCED VISIBILITIES IN BLOWING SNOW EVEN THOUGH LOWER ELEVATIONS
SHOULD NOT SEE MUCH FOR ACCUMULATIONS. MADE IT A POINT TO MENTION
THIS IN THE NPW PRODUCT.

SOMEWHAT CONCERNED THAT SOME OF THE ADJACENT VALLEYS AND HIGH PLAINS
MAY GET IN ON SOME OF THE WINDY FUN TOMORROW AS WELL. THERE ARE SOME
KEY DIFFERENCES IN THE GFS AND NAM WHICH WILL HAVE A ROLE IN WHETHER
OR NOT WE SEE WARNING CRITERIA WINDS AT AREAS SUCH AS CHEYENNE AND
THE LARAMIE VALLEY. FORECAST SOUNDINGS FROM BOTH MODELS SHOW A BELT
OF VERY STRONG FLOW NOT FAR OFF THE SURFACE. THE DIFFERENCES ARE IN
THE MIXING. MAIN LIMITING FACTOR WILL BE CLOUD COVER...BUT BOTH THE
LOW AND MID LEVEL RH FIELDS DO NOT SUGGEST ANYTHING THICK ENOUGH.
COULD EVENTUALLY SEE AN ABUNDANCE OF LENTICULARS EAST OF THE
MOUNTAINS AS MOUNTAIN WAVE ACTIVITY BECOMES INTENSE IN THE AFTN.
IF THIS DOES NOT IMPACT SURFACE HEATING...GFS SOUNDINGS SUGGEST
50-60 KT AT THE TOP OF THE MIXED LAYER AT LARAMIE AND CHEYENNE.
THE NAM IS CONSIDERABLY LESS...HOWEVER IT DOES SHOW SUBSIDENCE IN
ITS OMEGA FIELDS SPREADING SLOWLY ONTO THE PLAINS BETWEEN 18-00Z.
DECIDED TO ISSUE A HIGH WIND WATCH FOR LOWER ELEVATIONS
IMMEDIATELY ADJACENT TO THE LARAMIE RANGE AND FOOTHILLS. EVEN IF
AFTERNOON MIXING IS NOT THE CULPRIT...MODELS ARE IN GOOD AGREEMENT
WITH A TRANSITION TO A BORA WIND EVENT ON SAT NIGHT THROUGH EARLY
SUN AS A COLD FRONT SWEEPS ACROSS THE CWA. COULD SEE WIND GUSTS
RAMP UP AGAIN FOR A FEW HOURS AROUND MIDNIGHT...WITH A FEW GUSTS
TO 60 MPH POSSIBLE OVERNIGHT.

SUNDAY WILL BE VERY WINDY OVER THE PLAINS OF SOUTHEAST WYOMING AND
THE WESTERN PANHANDLE. THE CWA WILL BE IN THE POST FRONTAL AIR MASS
AND THE MODELS SHOW A RIBBON OF 60 TO 70 KT FROM NEAR LUSK
SOUTHEAST TOWARD SIDNEY AT 00Z MON. WILL LIKELY NEED MORE WIND
HEADLINES FOR THIS TIME FRAME...BUT WILL GET THROUGH THE SATURDAY
EVENT FIRST. NOW THAT THE WIND DISCUSSION IS OUT THE WAY...ONTO
THE SNOW POTENTIAL. DIDN`T MAKE ANY CHANGES TO THE WINTER STORM
WATCH FOR THE MOUNTAINS...BUT IT STILL LOOKS GOOD. CONVEYOR BELT OF
AN UPPER JET WITH 150+ KT H25 CORE IS PROGGED TO REMAIN ANCHORED
OVER THE WESTERN US FOR SEVERAL DAYS WITH OUR MOUNTAINS REMAINING
IN THE FAVORED LEFT EXIT REGION. THIS COMBINED WITH FAVORABLE
OROGRAPHICS IN WEST-NORTHWEST FLOW AND AND SEVERAL REINFORCING
SHOTS OF 700-300 MILLIBAR MOISTURE EMBEDDED IN THE ACTIVE FLOW
ALOFT WILL SUPPORT PERIODS OF HEAVY SNOW. SHOULD SEE ONE OR TWO
FEET THROUGH MON WITH ADDITIONAL SNOW POSSIBLE IN THE DAYS
FOLLOWING. SHOULD BE PRIMARILY A MOUNTAIN EVENT WITH AREAS EAST OF
THE LARAMIE RANGE STAYING DRY IN DOWNSLOPING LOW LEVEL FLOW. MAY
SEE A FEW RAIN OR SNOW SHOWERS OVER THE NORTHERN PANHANDLE ON SUN
AFTN AS PVA OVERSPREADS THE AREA.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

BASED ON GFS/ECMWF MODEL SOLUTIONS...SHOULD SEE A BREAK IN SNOW
ACCUMULATIONS OVER SOUTHEAST WYOMING MOUNTAINS SUNDAY EVENING WITH
A SHORTWAVE RIDGE IN PLACE. THEN THE NEXT SHOT OF SNOW LIKELY TO
DEVELOP AFTER MIDNIGHT SUNDAY NIGHT. COULD SEE SOME LIGHT SNOW
INTO LOWER ELEVATIONS BUT MOST SNOW ACCUMULATIONS WILL GENERALLY
BE IN THE MOUNTAINS. VERY LITTLE CHANCE FOR ANY ACCUMULATIONS
EAST OF THE LARAMIE RANGE SUNDAY NIGHT THROUGH MONDAY. WINDS WILL
SUBSIDE ACROSS MOST OF THE AREA SUNDAY NIGHT BUT ANOTHER PUSH OF
STRONGER WINDS POSSIBLE MONDAY NIGHT AS ANOTHER STRONG UPPER LEVEL
JET MOVES OVER THE AREA. MAIN CONCERN FOR HIGH WINDS WILL BE OVER
THE FAVORED WIND PRONE LOCATIONS IN SOUTHEAST WYOMING SUCH AS
ARLINGTON...BORDEAUX AND THE SOUTHERN LARAMIE RANGE.

THE NEXT QUICK MOVING CLIPPER SYSTEM ALONG WITH THE UPPER JET
WILL BRING A CHANCE FOR LIGHT SNOW SHOWERS THROUGH TUESDAY
AFTERNOON...INCLUDING INTO THE NEBRASKA PANHANDLE. AT THIS TIME
NOT EXPECTING MUCH IN THE WAY OF SNOW ACCUMULATIONS...IF ANY. MAINLY
LOOKING FOR LIGHT SNOW SHOWERS AND FLURRIES.

UNCERTAINTY REMAINS FOR LATER PORTIONS OF THE WEEK AND HOLIDAY
WEEKEND GIVEN THE GFS AND ECMWF WERE COMPLETELY DIFFERENT IN
THEIR SOLUTIONS YESTERDAY. HOWEVER...BOTH MODELS TRENDED TOWARD
EACH OTHER TODAY AND HAVE RATHER SIMILAR SOLUTIONS. WOULD LIKE TO
SEE RUN OR TWO OF CONSISTENCY BUT BASED ON LATEST SOLUTIONS IT
WOULD WARM BOTH THURSDAY AND FRIDAY WITH A FLATTENING RIDGE OVER
THE NORTHERN ROCKIES PRODUCING DOWNSLOPE WARMING. INTO THE WEEKEND
THE MODELS SUGGEST A FAST MOVING BUT RELATIVELY WEAK WAVE MOVING
ACROSS THE AREA...SO NO BIG HAZARDOUS WEATHER THREAT EXPECTED AT
THIS TIME.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1000 PM MST FRI NOV 21 2014

PRIMARY AVIATION CONCERNS WILL FOCUS ON STRONG WINDS OVERNIGHT
TONIGHT THROUGH SATURDAY NIGHT...WITH ACCUMULATING SNOW DEVELOPING
OVER THE MOUNTAINS SATURDAY AFTERNOON. FREQUENT GUSTS TO 50 KT AND
HIGHER WILL DEVELOP IN THE ARLINGTON AND BORDEAUX AREAS BETWEEN
09Z AND 12Z TONIGHT. THESE STRONG WEST TO SOUTHWEST WINDS WILL
THEN SPREAD INTO THE SOUTHERN AND NORTHERN LARAMIE RANGES SATURDAY
MORNING. GUSTY WINDS WILL ALSO SPREAD INTO LOWER ELEVATIONS AND
INTO THE PLAINS OF SOUTHEAST WYOMING SATURDAY AFTERNOON WITH GUSTS
OF 30 TO 40 KT COMMON. WINDS WILL NOT BE AS STRONG ACROSS THE
WESTERN NEBRASKA PANHANDLE BUT STILL BREEZY. THE MOUNTAINS WILL BE
OBSCURED DUE TO FALLING AND BLOWING SNOW SATURDAY AFTERNOON AND
EVENING.

&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WARNING FROM 2 AM SATURDAY TO 5 AM MST SUNDAY FOR
     WYZ103>106-110-116-117.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH LATE SATURDAY
     NIGHT FOR WYZ101-107-115-118.

NE...NONE.
&&

$$

UPDATE...MJ
SHORT TERM...CLH
LONG TERM...SML
AVIATION...MJ
FIRE WEATHER...RJM




000
FXUS65 KCYS 220407
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
907 PM MST FRI NOV 21 2014

.UPDATE...
ISSUED AT 906 PM MST FRI NOV 21 2014

H25-H50 WIND/HEIGHT SHOWED THE LEADING EDGE OF 90KT JET MAXIMA
MOVING ACROSS ID/WESTERN MT...AND WILL PROGRESS EASTWARD INTO WY
OVERNIGHT. COUPLED WITH H70-H85 GEOPOTENTIAL HEIGHT GRADIENTS FROM
CRAIG-CASPER EXCEEDING 60M...EXPECT HIGH WIND CRITERIA TO BE MET
IN THE ARLINGTON/BORDEAUX AREAS BETWEEN 09Z AND 12Z SAT. MOIST
ENERGETIC FLOW STILL FORECAST TO AFFECT AREAS WEST OF THE LARAMIE
RANGE BEGINNING SAT AFTERNOON. NO CHANGES PLANNED TO THE HIGH
WIND/WINTER STORM HEADLINES THIS EVENING.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

QUIET WEATHER IS QUICKLY COMING TO AN END AS WE TRANSITION INTO A
VERY ACTIVE PATTERN FOR THE SHORT TERM PERIOD. HIGHLIGHTS REVOLVE
AROUND POTENTIAL FOR VERY STRONG WINDS OVER SOUTHEAST WYOMING AND
POSSIBLY WESTERN NEBRASKA...AND MOUNTAIN SNOWS. LATEST WATER VAPOR
SATELLITE LOOP SHOWS A VIGOROUS UPPER-LEVEL SHORTWAVE JUST ABOUT TO
CRASH INTO THE PACIFIC NORTHWEST THIS EVE. OBJECTIVE UPPER ANALYSIS
SHOWS A STRONG 110+ KT JET CORE OFFSHORE AT 21Z. THIS WILL BE OUR
MAJOR WEATHER MAKER OVER THE NEXT COUPLE OF DAYS AS THE SYSTEM MOVES
RAPIDLY SOUTHEAST AND STRENGTHENS. NOT EXPECTING ANYTHING MAJOR IN
THE NEAR TERM THOUGH. SHOULD BE A QUIET EVENING WITH WINDS STARTING
TO RELAX AS MIXING DWINDLES WITH THE LOSS OF AFTN HEATING. A BROAD
AREA OF SURFACE HIGH PRESSURE WILL KEEP THINGS ON THE DRY SIDE.

THINGS CHANGE QUICKLY INTO TONIGHT. THE NAM H85 CAG-CPR GRADIENT IS
PROGGED TO CLIMB ABOVE 60 METERS BY ABOUT 09Z SAT. MODELED LOW
LEVEL FLOW IS IMPRESSIVE TO SAY THE LEAST WITH AN EXTENSIVE CORE
OF 60 TO 70 KT WINDS BETWEEN 700 AND 800 MILLIBARS OVER A GOOD
CHUNK OF OUR WYOMING ZONES BY SUNRISE. WITH EXCELLENT SUBSIDENCE
OVER THE TRADITIONAL GAP AREAS AND GOOD 6-HR PRESSURE FALLS ON THE
ORDER OF 5-10 MB PER THE GFS...CONFIDENCE IS HIGH IN A WIDESPREAD
AND POTENTIALLY SIGNIFICANT WIND EVENT. WENT AHEAD AND UPGRADED TO
A HIGH WIND WARNING WITH ALL ZONES STARTING AT 09Z. ARL AND BRX
SHOULD HIT FIRST...WITH THE WIND CORE ALOFT SPREADING INTO THE
SOUTHERN LARAMIE RANGE/FOOTHILLS AT OR AROUND SUNRISE. ADDED THE
NORTHERN LARAMIE RANGE TO THE WARNING AS WELL AS BOTH THE GFS AND
NAM SHOW 65 KT WINDS AT H75 TO THE SOUTH OF DEER CREEK IN WESTERN
CONVERSE COUNTY. THIS MAY BE QUITE THE EVENT WITH MULTIPLE GUSTS
OVER 70 MPH. ANOTHER EVENTUAL CONCERN IS THE POTENTIAL FOR LIGHT
SNOW WEST OF THE LARAMIE RANGE LATER IN THE AFTERNOON AND EVENING.
WITH STRONG WINDS WILL COME THE POTENTIAL FOR SIGNIFICANTLY
REDUCED VISIBILITIES IN BLOWING SNOW EVEN THOUGH LOWER ELEVATIONS
SHOULD NOT SEE MUCH FOR ACCUMULATIONS. MADE IT A POINT TO MENTION
THIS IN THE NPW PRODUCT.

SOMEWHAT CONCERNED THAT SOME OF THE ADJACENT VALLEYS AND HIGH PLAINS
MAY GET IN ON SOME OF THE WINDY FUN TOMORROW AS WELL. THERE ARE SOME
KEY DIFFERENCES IN THE GFS AND NAM WHICH WILL HAVE A ROLE IN WHETHER
OR NOT WE SEE WARNING CRITERIA WINDS AT AREAS SUCH AS CHEYENNE AND
THE LARAMIE VALLEY. FORECAST SOUNDINGS FROM BOTH MODELS SHOW A BELT
OF VERY STRONG FLOW NOT FAR OFF THE SURFACE. THE DIFFERENCES ARE IN
THE MIXING. MAIN LIMITING FACTOR WILL BE CLOUD COVER...BUT BOTH THE
LOW AND MID LEVEL RH FIELDS DO NOT SUGGEST ANYTHING THICK ENOUGH.
COULD EVENTUALLY SEE AN ABUNDANCE OF LENTICULARS EAST OF THE
MOUNTAINS AS MOUNTAIN WAVE ACTIVITY BECOMES INTENSE IN THE AFTN.
IF THIS DOES NOT IMPACT SURFACE HEATING...GFS SOUNDINGS SUGGEST
50-60 KT AT THE TOP OF THE MIXED LAYER AT LARAMIE AND CHEYENNE.
THE NAM IS CONSIDERABLY LESS...HOWEVER IT DOES SHOW SUBSIDENCE IN
ITS OMEGA FIELDS SPREADING SLOWLY ONTO THE PLAINS BETWEEN 18-00Z.
DECIDED TO ISSUE A HIGH WIND WATCH FOR LOWER ELEVATIONS
IMMEDIATELY ADJACENT TO THE LARAMIE RANGE AND FOOTHILLS. EVEN IF
AFTERNOON MIXING IS NOT THE CULPRIT...MODELS ARE IN GOOD AGREEMENT
WITH A TRANSITION TO A BORA WIND EVENT ON SAT NIGHT THROUGH EARLY
SUN AS A COLD FRONT SWEEPS ACROSS THE CWA. COULD SEE WIND GUSTS
RAMP UP AGAIN FOR A FEW HOURS AROUND MIDNIGHT...WITH A FEW GUSTS
TO 60 MPH POSSIBLE OVERNIGHT.

SUNDAY WILL BE VERY WINDY OVER THE PLAINS OF SOUTHEAST WYOMING AND
THE WESTERN PANHANDLE. THE CWA WILL BE IN THE POST FRONTAL AIR MASS
AND THE MODELS SHOW A RIBBON OF 60 TO 70 KT FROM NEAR LUSK
SOUTHEAST TOWARD SIDNEY AT 00Z MON. WILL LIKELY NEED MORE WIND
HEADLINES FOR THIS TIME FRAME...BUT WILL GET THROUGH THE SATURDAY
EVENT FIRST. NOW THAT THE WIND DISCUSSION IS OUT THE WAY...ONTO
THE SNOW POTENTIAL. DIDN`T MAKE ANY CHANGES TO THE WINTER STORM
WATCH FOR THE MOUNTAINS...BUT IT STILL LOOKS GOOD. CONVEYOR BELT OF
AN UPPER JET WITH 150+ KT H25 CORE IS PROGGED TO REMAIN ANCHORED
OVER THE WESTERN US FOR SEVERAL DAYS WITH OUR MOUNTAINS REMAINING
IN THE FAVORED LEFT EXIT REGION. THIS COMBINED WITH FAVORABLE
OROGRAPHICS IN WEST-NORTHWEST FLOW AND AND SEVERAL REINFORCING
SHOTS OF 700-300 MILLIBAR MOISTURE EMBEDDED IN THE ACTIVE FLOW
ALOFT WILL SUPPORT PERIODS OF HEAVY SNOW. SHOULD SEE ONE OR TWO
FEET THROUGH MON WITH ADDITIONAL SNOW POSSIBLE IN THE DAYS
FOLLOWING. SHOULD BE PRIMARILY A MOUNTAIN EVENT WITH AREAS EAST OF
THE LARAMIE RANGE STAYING DRY IN DOWNSLOPING LOW LEVEL FLOW. MAY
SEE A FEW RAIN OR SNOW SHOWERS OVER THE NORTHERN PANHANDLE ON SUN
AFTN AS PVA OVERSPREADS THE AREA.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

BASED ON GFS/ECMWF MODEL SOLUTIONS...SHOULD SEE A BREAK IN SNOW
ACCUMULATIONS OVER SOUTHEAST WYOMING MOUNTAINS SUNDAY EVENING WITH
A SHORTWAVE RIDGE IN PLACE. THEN THE NEXT SHOT OF SNOW LIKELY TO
DEVELOP AFTER MIDNIGHT SUNDAY NIGHT. COULD SEE SOME LIGHT SNOW
INTO LOWER ELEVATIONS BUT MOST SNOW ACCUMULATIONS WILL GENERALLY
BE IN THE MOUNTAINS. VERY LITTLE CHANCE FOR ANY ACCUMULATIONS
EAST OF THE LARAMIE RANGE SUNDAY NIGHT THROUGH MONDAY. WINDS WILL
SUBSIDE ACROSS MOST OF THE AREA SUNDAY NIGHT BUT ANOTHER PUSH OF
STRONGER WINDS POSSIBLE MONDAY NIGHT AS ANOTHER STRONG UPPER LEVEL
JET MOVES OVER THE AREA. MAIN CONCERN FOR HIGH WINDS WILL BE OVER
THE FAVORED WIND PRONE LOCATIONS IN SOUTHEAST WYOMING SUCH AS
ARLINGTON...BORDEAUX AND THE SOUTHERN LARAMIE RANGE.

THE NEXT QUICK MOVING CLIPPER SYSTEM ALONG WITH THE UPPER JET
WILL BRING A CHANCE FOR LIGHT SNOW SHOWERS THROUGH TUESDAY
AFTERNOON...INCLUDING INTO THE NEBRASKA PANHANDLE. AT THIS TIME
NOT EXPECTING MUCH IN THE WAY OF SNOW ACCUMULATIONS...IF ANY. MAINLY
LOOKING FOR LIGHT SNOW SHOWERS AND FLURRIES.

UNCERTAINTY REMAINS FOR LATER PORTIONS OF THE WEEK AND HOLIDAY
WEEKEND GIVEN THE GFS AND ECMWF WERE COMPLETELY DIFFERENT IN
THEIR SOLUTIONS YESTERDAY. HOWEVER...BOTH MODELS TRENDED TOWARD
EACH OTHER TODAY AND HAVE RATHER SIMILAR SOLUTIONS. WOULD LIKE TO
SEE RUN OR TWO OF CONSISTENCY BUT BASED ON LATEST SOLUTIONS IT
WOULD WARM BOTH THURSDAY AND FRIDAY WITH A FLATTENING RIDGE OVER
THE NORTHERN ROCKIES PRODUCING DOWNSLOPE WARMING. INTO THE WEEKEND
THE MODELS SUGGEST A FAST MOVING BUT RELATIVELY WEAK WAVE MOVING
ACROSS THE AREA...SO NO BIG HAZARDOUS WEATHER THREAT EXPECTED AT
THIS TIME.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 234 PM MST FRI NOV 21 2014

AVIATION CONCERNS TO MAINLY FOCUS ON WINDS LATE TONIGHT AND INTO
TOMORROW AND SNOW WHICH WILL DEVELOP OVER THE MOUNTAINS TOMORROW
AFTERNOON. STRONG WINDS WITH FREQUENT GUSTS TO 50 KT AND GREATER
WILL DEVELOP IN THE ARLINGTON AREA AND INTO THE BORDEAUX AREA LATE
TONIGHT. THESE STRONG WEST TO SOUTHWEST WINDS WILL THEN SPREAD
INTO THE SOUTHERN AND NORTHERN LARAMIE RANGES TOWARD SUNRISE
SATURDAY. GUSTY WINDS WILL ALSO SPREAD INTO LOWER ELEVATIONS AND
INTO THE PLAINS OF SOUTHEAST WYOMING SATURDAY AFTERNOON WITH GUSTS
OF 30 TO 40 KT BEING COMMON. WINDS WILL NOT BE AS STRONG INTO THE
NEBRASKA PANHANDLE BUT STILL BREEZY TO WINDY SATURDAY AFTERNOON.

MOUNTAINS WILL BE OBSCURED DUE TO FALLING AND BLOWING SNOW
SATURDAY AFTERNOON...ESPECIALLY INTO THE SNOWY AND SIERRA MADRE
RANGES WHERE A WINTER STORM WATCH IS CURRENTLY IN EFFECT. PERIODS
OF SNOW WILL CONTINUE INTO MONDAY ACROSS THESE MOUNTAINS.

STRONG NORTHWEST WINDS EXPECTED OVER THE NEBRASKA PANHANDLE SUNDAY
WITH STRONGER WINDS ALSO POSSIBLE INTO SOUTHEAST WYOMING.


&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WARNING FROM 2 AM SATURDAY TO 5 AM MST SUNDAY FOR
     WYZ103>106-110-116-117.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH LATE SATURDAY
     NIGHT FOR WYZ101-107-115-118.

NE...NONE.
&&

$$

UPDATE...MJ
SHORT TERM...CLH
LONG TERM...SML
AVIATION...SML
FIRE WEATHER...RJM



000
FXUS65 KCYS 220407
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
907 PM MST FRI NOV 21 2014

.UPDATE...
ISSUED AT 906 PM MST FRI NOV 21 2014

H25-H50 WIND/HEIGHT SHOWED THE LEADING EDGE OF 90KT JET MAXIMA
MOVING ACROSS ID/WESTERN MT...AND WILL PROGRESS EASTWARD INTO WY
OVERNIGHT. COUPLED WITH H70-H85 GEOPOTENTIAL HEIGHT GRADIENTS FROM
CRAIG-CASPER EXCEEDING 60M...EXPECT HIGH WIND CRITERIA TO BE MET
IN THE ARLINGTON/BORDEAUX AREAS BETWEEN 09Z AND 12Z SAT. MOIST
ENERGETIC FLOW STILL FORECAST TO AFFECT AREAS WEST OF THE LARAMIE
RANGE BEGINNING SAT AFTERNOON. NO CHANGES PLANNED TO THE HIGH
WIND/WINTER STORM HEADLINES THIS EVENING.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

QUIET WEATHER IS QUICKLY COMING TO AN END AS WE TRANSITION INTO A
VERY ACTIVE PATTERN FOR THE SHORT TERM PERIOD. HIGHLIGHTS REVOLVE
AROUND POTENTIAL FOR VERY STRONG WINDS OVER SOUTHEAST WYOMING AND
POSSIBLY WESTERN NEBRASKA...AND MOUNTAIN SNOWS. LATEST WATER VAPOR
SATELLITE LOOP SHOWS A VIGOROUS UPPER-LEVEL SHORTWAVE JUST ABOUT TO
CRASH INTO THE PACIFIC NORTHWEST THIS EVE. OBJECTIVE UPPER ANALYSIS
SHOWS A STRONG 110+ KT JET CORE OFFSHORE AT 21Z. THIS WILL BE OUR
MAJOR WEATHER MAKER OVER THE NEXT COUPLE OF DAYS AS THE SYSTEM MOVES
RAPIDLY SOUTHEAST AND STRENGTHENS. NOT EXPECTING ANYTHING MAJOR IN
THE NEAR TERM THOUGH. SHOULD BE A QUIET EVENING WITH WINDS STARTING
TO RELAX AS MIXING DWINDLES WITH THE LOSS OF AFTN HEATING. A BROAD
AREA OF SURFACE HIGH PRESSURE WILL KEEP THINGS ON THE DRY SIDE.

THINGS CHANGE QUICKLY INTO TONIGHT. THE NAM H85 CAG-CPR GRADIENT IS
PROGGED TO CLIMB ABOVE 60 METERS BY ABOUT 09Z SAT. MODELED LOW
LEVEL FLOW IS IMPRESSIVE TO SAY THE LEAST WITH AN EXTENSIVE CORE
OF 60 TO 70 KT WINDS BETWEEN 700 AND 800 MILLIBARS OVER A GOOD
CHUNK OF OUR WYOMING ZONES BY SUNRISE. WITH EXCELLENT SUBSIDENCE
OVER THE TRADITIONAL GAP AREAS AND GOOD 6-HR PRESSURE FALLS ON THE
ORDER OF 5-10 MB PER THE GFS...CONFIDENCE IS HIGH IN A WIDESPREAD
AND POTENTIALLY SIGNIFICANT WIND EVENT. WENT AHEAD AND UPGRADED TO
A HIGH WIND WARNING WITH ALL ZONES STARTING AT 09Z. ARL AND BRX
SHOULD HIT FIRST...WITH THE WIND CORE ALOFT SPREADING INTO THE
SOUTHERN LARAMIE RANGE/FOOTHILLS AT OR AROUND SUNRISE. ADDED THE
NORTHERN LARAMIE RANGE TO THE WARNING AS WELL AS BOTH THE GFS AND
NAM SHOW 65 KT WINDS AT H75 TO THE SOUTH OF DEER CREEK IN WESTERN
CONVERSE COUNTY. THIS MAY BE QUITE THE EVENT WITH MULTIPLE GUSTS
OVER 70 MPH. ANOTHER EVENTUAL CONCERN IS THE POTENTIAL FOR LIGHT
SNOW WEST OF THE LARAMIE RANGE LATER IN THE AFTERNOON AND EVENING.
WITH STRONG WINDS WILL COME THE POTENTIAL FOR SIGNIFICANTLY
REDUCED VISIBILITIES IN BLOWING SNOW EVEN THOUGH LOWER ELEVATIONS
SHOULD NOT SEE MUCH FOR ACCUMULATIONS. MADE IT A POINT TO MENTION
THIS IN THE NPW PRODUCT.

SOMEWHAT CONCERNED THAT SOME OF THE ADJACENT VALLEYS AND HIGH PLAINS
MAY GET IN ON SOME OF THE WINDY FUN TOMORROW AS WELL. THERE ARE SOME
KEY DIFFERENCES IN THE GFS AND NAM WHICH WILL HAVE A ROLE IN WHETHER
OR NOT WE SEE WARNING CRITERIA WINDS AT AREAS SUCH AS CHEYENNE AND
THE LARAMIE VALLEY. FORECAST SOUNDINGS FROM BOTH MODELS SHOW A BELT
OF VERY STRONG FLOW NOT FAR OFF THE SURFACE. THE DIFFERENCES ARE IN
THE MIXING. MAIN LIMITING FACTOR WILL BE CLOUD COVER...BUT BOTH THE
LOW AND MID LEVEL RH FIELDS DO NOT SUGGEST ANYTHING THICK ENOUGH.
COULD EVENTUALLY SEE AN ABUNDANCE OF LENTICULARS EAST OF THE
MOUNTAINS AS MOUNTAIN WAVE ACTIVITY BECOMES INTENSE IN THE AFTN.
IF THIS DOES NOT IMPACT SURFACE HEATING...GFS SOUNDINGS SUGGEST
50-60 KT AT THE TOP OF THE MIXED LAYER AT LARAMIE AND CHEYENNE.
THE NAM IS CONSIDERABLY LESS...HOWEVER IT DOES SHOW SUBSIDENCE IN
ITS OMEGA FIELDS SPREADING SLOWLY ONTO THE PLAINS BETWEEN 18-00Z.
DECIDED TO ISSUE A HIGH WIND WATCH FOR LOWER ELEVATIONS
IMMEDIATELY ADJACENT TO THE LARAMIE RANGE AND FOOTHILLS. EVEN IF
AFTERNOON MIXING IS NOT THE CULPRIT...MODELS ARE IN GOOD AGREEMENT
WITH A TRANSITION TO A BORA WIND EVENT ON SAT NIGHT THROUGH EARLY
SUN AS A COLD FRONT SWEEPS ACROSS THE CWA. COULD SEE WIND GUSTS
RAMP UP AGAIN FOR A FEW HOURS AROUND MIDNIGHT...WITH A FEW GUSTS
TO 60 MPH POSSIBLE OVERNIGHT.

SUNDAY WILL BE VERY WINDY OVER THE PLAINS OF SOUTHEAST WYOMING AND
THE WESTERN PANHANDLE. THE CWA WILL BE IN THE POST FRONTAL AIR MASS
AND THE MODELS SHOW A RIBBON OF 60 TO 70 KT FROM NEAR LUSK
SOUTHEAST TOWARD SIDNEY AT 00Z MON. WILL LIKELY NEED MORE WIND
HEADLINES FOR THIS TIME FRAME...BUT WILL GET THROUGH THE SATURDAY
EVENT FIRST. NOW THAT THE WIND DISCUSSION IS OUT THE WAY...ONTO
THE SNOW POTENTIAL. DIDN`T MAKE ANY CHANGES TO THE WINTER STORM
WATCH FOR THE MOUNTAINS...BUT IT STILL LOOKS GOOD. CONVEYOR BELT OF
AN UPPER JET WITH 150+ KT H25 CORE IS PROGGED TO REMAIN ANCHORED
OVER THE WESTERN US FOR SEVERAL DAYS WITH OUR MOUNTAINS REMAINING
IN THE FAVORED LEFT EXIT REGION. THIS COMBINED WITH FAVORABLE
OROGRAPHICS IN WEST-NORTHWEST FLOW AND AND SEVERAL REINFORCING
SHOTS OF 700-300 MILLIBAR MOISTURE EMBEDDED IN THE ACTIVE FLOW
ALOFT WILL SUPPORT PERIODS OF HEAVY SNOW. SHOULD SEE ONE OR TWO
FEET THROUGH MON WITH ADDITIONAL SNOW POSSIBLE IN THE DAYS
FOLLOWING. SHOULD BE PRIMARILY A MOUNTAIN EVENT WITH AREAS EAST OF
THE LARAMIE RANGE STAYING DRY IN DOWNSLOPING LOW LEVEL FLOW. MAY
SEE A FEW RAIN OR SNOW SHOWERS OVER THE NORTHERN PANHANDLE ON SUN
AFTN AS PVA OVERSPREADS THE AREA.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

BASED ON GFS/ECMWF MODEL SOLUTIONS...SHOULD SEE A BREAK IN SNOW
ACCUMULATIONS OVER SOUTHEAST WYOMING MOUNTAINS SUNDAY EVENING WITH
A SHORTWAVE RIDGE IN PLACE. THEN THE NEXT SHOT OF SNOW LIKELY TO
DEVELOP AFTER MIDNIGHT SUNDAY NIGHT. COULD SEE SOME LIGHT SNOW
INTO LOWER ELEVATIONS BUT MOST SNOW ACCUMULATIONS WILL GENERALLY
BE IN THE MOUNTAINS. VERY LITTLE CHANCE FOR ANY ACCUMULATIONS
EAST OF THE LARAMIE RANGE SUNDAY NIGHT THROUGH MONDAY. WINDS WILL
SUBSIDE ACROSS MOST OF THE AREA SUNDAY NIGHT BUT ANOTHER PUSH OF
STRONGER WINDS POSSIBLE MONDAY NIGHT AS ANOTHER STRONG UPPER LEVEL
JET MOVES OVER THE AREA. MAIN CONCERN FOR HIGH WINDS WILL BE OVER
THE FAVORED WIND PRONE LOCATIONS IN SOUTHEAST WYOMING SUCH AS
ARLINGTON...BORDEAUX AND THE SOUTHERN LARAMIE RANGE.

THE NEXT QUICK MOVING CLIPPER SYSTEM ALONG WITH THE UPPER JET
WILL BRING A CHANCE FOR LIGHT SNOW SHOWERS THROUGH TUESDAY
AFTERNOON...INCLUDING INTO THE NEBRASKA PANHANDLE. AT THIS TIME
NOT EXPECTING MUCH IN THE WAY OF SNOW ACCUMULATIONS...IF ANY. MAINLY
LOOKING FOR LIGHT SNOW SHOWERS AND FLURRIES.

UNCERTAINTY REMAINS FOR LATER PORTIONS OF THE WEEK AND HOLIDAY
WEEKEND GIVEN THE GFS AND ECMWF WERE COMPLETELY DIFFERENT IN
THEIR SOLUTIONS YESTERDAY. HOWEVER...BOTH MODELS TRENDED TOWARD
EACH OTHER TODAY AND HAVE RATHER SIMILAR SOLUTIONS. WOULD LIKE TO
SEE RUN OR TWO OF CONSISTENCY BUT BASED ON LATEST SOLUTIONS IT
WOULD WARM BOTH THURSDAY AND FRIDAY WITH A FLATTENING RIDGE OVER
THE NORTHERN ROCKIES PRODUCING DOWNSLOPE WARMING. INTO THE WEEKEND
THE MODELS SUGGEST A FAST MOVING BUT RELATIVELY WEAK WAVE MOVING
ACROSS THE AREA...SO NO BIG HAZARDOUS WEATHER THREAT EXPECTED AT
THIS TIME.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 234 PM MST FRI NOV 21 2014

AVIATION CONCERNS TO MAINLY FOCUS ON WINDS LATE TONIGHT AND INTO
TOMORROW AND SNOW WHICH WILL DEVELOP OVER THE MOUNTAINS TOMORROW
AFTERNOON. STRONG WINDS WITH FREQUENT GUSTS TO 50 KT AND GREATER
WILL DEVELOP IN THE ARLINGTON AREA AND INTO THE BORDEAUX AREA LATE
TONIGHT. THESE STRONG WEST TO SOUTHWEST WINDS WILL THEN SPREAD
INTO THE SOUTHERN AND NORTHERN LARAMIE RANGES TOWARD SUNRISE
SATURDAY. GUSTY WINDS WILL ALSO SPREAD INTO LOWER ELEVATIONS AND
INTO THE PLAINS OF SOUTHEAST WYOMING SATURDAY AFTERNOON WITH GUSTS
OF 30 TO 40 KT BEING COMMON. WINDS WILL NOT BE AS STRONG INTO THE
NEBRASKA PANHANDLE BUT STILL BREEZY TO WINDY SATURDAY AFTERNOON.

MOUNTAINS WILL BE OBSCURED DUE TO FALLING AND BLOWING SNOW
SATURDAY AFTERNOON...ESPECIALLY INTO THE SNOWY AND SIERRA MADRE
RANGES WHERE A WINTER STORM WATCH IS CURRENTLY IN EFFECT. PERIODS
OF SNOW WILL CONTINUE INTO MONDAY ACROSS THESE MOUNTAINS.

STRONG NORTHWEST WINDS EXPECTED OVER THE NEBRASKA PANHANDLE SUNDAY
WITH STRONGER WINDS ALSO POSSIBLE INTO SOUTHEAST WYOMING.


&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WARNING FROM 2 AM SATURDAY TO 5 AM MST SUNDAY FOR
     WYZ103>106-110-116-117.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH LATE SATURDAY
     NIGHT FOR WYZ101-107-115-118.

NE...NONE.
&&

$$

UPDATE...MJ
SHORT TERM...CLH
LONG TERM...SML
AVIATION...SML
FIRE WEATHER...RJM




000
FXUS65 KCYS 220407
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
907 PM MST FRI NOV 21 2014

.UPDATE...
ISSUED AT 906 PM MST FRI NOV 21 2014

H25-H50 WIND/HEIGHT SHOWED THE LEADING EDGE OF 90KT JET MAXIMA
MOVING ACROSS ID/WESTERN MT...AND WILL PROGRESS EASTWARD INTO WY
OVERNIGHT. COUPLED WITH H70-H85 GEOPOTENTIAL HEIGHT GRADIENTS FROM
CRAIG-CASPER EXCEEDING 60M...EXPECT HIGH WIND CRITERIA TO BE MET
IN THE ARLINGTON/BORDEAUX AREAS BETWEEN 09Z AND 12Z SAT. MOIST
ENERGETIC FLOW STILL FORECAST TO AFFECT AREAS WEST OF THE LARAMIE
RANGE BEGINNING SAT AFTERNOON. NO CHANGES PLANNED TO THE HIGH
WIND/WINTER STORM HEADLINES THIS EVENING.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

QUIET WEATHER IS QUICKLY COMING TO AN END AS WE TRANSITION INTO A
VERY ACTIVE PATTERN FOR THE SHORT TERM PERIOD. HIGHLIGHTS REVOLVE
AROUND POTENTIAL FOR VERY STRONG WINDS OVER SOUTHEAST WYOMING AND
POSSIBLY WESTERN NEBRASKA...AND MOUNTAIN SNOWS. LATEST WATER VAPOR
SATELLITE LOOP SHOWS A VIGOROUS UPPER-LEVEL SHORTWAVE JUST ABOUT TO
CRASH INTO THE PACIFIC NORTHWEST THIS EVE. OBJECTIVE UPPER ANALYSIS
SHOWS A STRONG 110+ KT JET CORE OFFSHORE AT 21Z. THIS WILL BE OUR
MAJOR WEATHER MAKER OVER THE NEXT COUPLE OF DAYS AS THE SYSTEM MOVES
RAPIDLY SOUTHEAST AND STRENGTHENS. NOT EXPECTING ANYTHING MAJOR IN
THE NEAR TERM THOUGH. SHOULD BE A QUIET EVENING WITH WINDS STARTING
TO RELAX AS MIXING DWINDLES WITH THE LOSS OF AFTN HEATING. A BROAD
AREA OF SURFACE HIGH PRESSURE WILL KEEP THINGS ON THE DRY SIDE.

THINGS CHANGE QUICKLY INTO TONIGHT. THE NAM H85 CAG-CPR GRADIENT IS
PROGGED TO CLIMB ABOVE 60 METERS BY ABOUT 09Z SAT. MODELED LOW
LEVEL FLOW IS IMPRESSIVE TO SAY THE LEAST WITH AN EXTENSIVE CORE
OF 60 TO 70 KT WINDS BETWEEN 700 AND 800 MILLIBARS OVER A GOOD
CHUNK OF OUR WYOMING ZONES BY SUNRISE. WITH EXCELLENT SUBSIDENCE
OVER THE TRADITIONAL GAP AREAS AND GOOD 6-HR PRESSURE FALLS ON THE
ORDER OF 5-10 MB PER THE GFS...CONFIDENCE IS HIGH IN A WIDESPREAD
AND POTENTIALLY SIGNIFICANT WIND EVENT. WENT AHEAD AND UPGRADED TO
A HIGH WIND WARNING WITH ALL ZONES STARTING AT 09Z. ARL AND BRX
SHOULD HIT FIRST...WITH THE WIND CORE ALOFT SPREADING INTO THE
SOUTHERN LARAMIE RANGE/FOOTHILLS AT OR AROUND SUNRISE. ADDED THE
NORTHERN LARAMIE RANGE TO THE WARNING AS WELL AS BOTH THE GFS AND
NAM SHOW 65 KT WINDS AT H75 TO THE SOUTH OF DEER CREEK IN WESTERN
CONVERSE COUNTY. THIS MAY BE QUITE THE EVENT WITH MULTIPLE GUSTS
OVER 70 MPH. ANOTHER EVENTUAL CONCERN IS THE POTENTIAL FOR LIGHT
SNOW WEST OF THE LARAMIE RANGE LATER IN THE AFTERNOON AND EVENING.
WITH STRONG WINDS WILL COME THE POTENTIAL FOR SIGNIFICANTLY
REDUCED VISIBILITIES IN BLOWING SNOW EVEN THOUGH LOWER ELEVATIONS
SHOULD NOT SEE MUCH FOR ACCUMULATIONS. MADE IT A POINT TO MENTION
THIS IN THE NPW PRODUCT.

SOMEWHAT CONCERNED THAT SOME OF THE ADJACENT VALLEYS AND HIGH PLAINS
MAY GET IN ON SOME OF THE WINDY FUN TOMORROW AS WELL. THERE ARE SOME
KEY DIFFERENCES IN THE GFS AND NAM WHICH WILL HAVE A ROLE IN WHETHER
OR NOT WE SEE WARNING CRITERIA WINDS AT AREAS SUCH AS CHEYENNE AND
THE LARAMIE VALLEY. FORECAST SOUNDINGS FROM BOTH MODELS SHOW A BELT
OF VERY STRONG FLOW NOT FAR OFF THE SURFACE. THE DIFFERENCES ARE IN
THE MIXING. MAIN LIMITING FACTOR WILL BE CLOUD COVER...BUT BOTH THE
LOW AND MID LEVEL RH FIELDS DO NOT SUGGEST ANYTHING THICK ENOUGH.
COULD EVENTUALLY SEE AN ABUNDANCE OF LENTICULARS EAST OF THE
MOUNTAINS AS MOUNTAIN WAVE ACTIVITY BECOMES INTENSE IN THE AFTN.
IF THIS DOES NOT IMPACT SURFACE HEATING...GFS SOUNDINGS SUGGEST
50-60 KT AT THE TOP OF THE MIXED LAYER AT LARAMIE AND CHEYENNE.
THE NAM IS CONSIDERABLY LESS...HOWEVER IT DOES SHOW SUBSIDENCE IN
ITS OMEGA FIELDS SPREADING SLOWLY ONTO THE PLAINS BETWEEN 18-00Z.
DECIDED TO ISSUE A HIGH WIND WATCH FOR LOWER ELEVATIONS
IMMEDIATELY ADJACENT TO THE LARAMIE RANGE AND FOOTHILLS. EVEN IF
AFTERNOON MIXING IS NOT THE CULPRIT...MODELS ARE IN GOOD AGREEMENT
WITH A TRANSITION TO A BORA WIND EVENT ON SAT NIGHT THROUGH EARLY
SUN AS A COLD FRONT SWEEPS ACROSS THE CWA. COULD SEE WIND GUSTS
RAMP UP AGAIN FOR A FEW HOURS AROUND MIDNIGHT...WITH A FEW GUSTS
TO 60 MPH POSSIBLE OVERNIGHT.

SUNDAY WILL BE VERY WINDY OVER THE PLAINS OF SOUTHEAST WYOMING AND
THE WESTERN PANHANDLE. THE CWA WILL BE IN THE POST FRONTAL AIR MASS
AND THE MODELS SHOW A RIBBON OF 60 TO 70 KT FROM NEAR LUSK
SOUTHEAST TOWARD SIDNEY AT 00Z MON. WILL LIKELY NEED MORE WIND
HEADLINES FOR THIS TIME FRAME...BUT WILL GET THROUGH THE SATURDAY
EVENT FIRST. NOW THAT THE WIND DISCUSSION IS OUT THE WAY...ONTO
THE SNOW POTENTIAL. DIDN`T MAKE ANY CHANGES TO THE WINTER STORM
WATCH FOR THE MOUNTAINS...BUT IT STILL LOOKS GOOD. CONVEYOR BELT OF
AN UPPER JET WITH 150+ KT H25 CORE IS PROGGED TO REMAIN ANCHORED
OVER THE WESTERN US FOR SEVERAL DAYS WITH OUR MOUNTAINS REMAINING
IN THE FAVORED LEFT EXIT REGION. THIS COMBINED WITH FAVORABLE
OROGRAPHICS IN WEST-NORTHWEST FLOW AND AND SEVERAL REINFORCING
SHOTS OF 700-300 MILLIBAR MOISTURE EMBEDDED IN THE ACTIVE FLOW
ALOFT WILL SUPPORT PERIODS OF HEAVY SNOW. SHOULD SEE ONE OR TWO
FEET THROUGH MON WITH ADDITIONAL SNOW POSSIBLE IN THE DAYS
FOLLOWING. SHOULD BE PRIMARILY A MOUNTAIN EVENT WITH AREAS EAST OF
THE LARAMIE RANGE STAYING DRY IN DOWNSLOPING LOW LEVEL FLOW. MAY
SEE A FEW RAIN OR SNOW SHOWERS OVER THE NORTHERN PANHANDLE ON SUN
AFTN AS PVA OVERSPREADS THE AREA.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

BASED ON GFS/ECMWF MODEL SOLUTIONS...SHOULD SEE A BREAK IN SNOW
ACCUMULATIONS OVER SOUTHEAST WYOMING MOUNTAINS SUNDAY EVENING WITH
A SHORTWAVE RIDGE IN PLACE. THEN THE NEXT SHOT OF SNOW LIKELY TO
DEVELOP AFTER MIDNIGHT SUNDAY NIGHT. COULD SEE SOME LIGHT SNOW
INTO LOWER ELEVATIONS BUT MOST SNOW ACCUMULATIONS WILL GENERALLY
BE IN THE MOUNTAINS. VERY LITTLE CHANCE FOR ANY ACCUMULATIONS
EAST OF THE LARAMIE RANGE SUNDAY NIGHT THROUGH MONDAY. WINDS WILL
SUBSIDE ACROSS MOST OF THE AREA SUNDAY NIGHT BUT ANOTHER PUSH OF
STRONGER WINDS POSSIBLE MONDAY NIGHT AS ANOTHER STRONG UPPER LEVEL
JET MOVES OVER THE AREA. MAIN CONCERN FOR HIGH WINDS WILL BE OVER
THE FAVORED WIND PRONE LOCATIONS IN SOUTHEAST WYOMING SUCH AS
ARLINGTON...BORDEAUX AND THE SOUTHERN LARAMIE RANGE.

THE NEXT QUICK MOVING CLIPPER SYSTEM ALONG WITH THE UPPER JET
WILL BRING A CHANCE FOR LIGHT SNOW SHOWERS THROUGH TUESDAY
AFTERNOON...INCLUDING INTO THE NEBRASKA PANHANDLE. AT THIS TIME
NOT EXPECTING MUCH IN THE WAY OF SNOW ACCUMULATIONS...IF ANY. MAINLY
LOOKING FOR LIGHT SNOW SHOWERS AND FLURRIES.

UNCERTAINTY REMAINS FOR LATER PORTIONS OF THE WEEK AND HOLIDAY
WEEKEND GIVEN THE GFS AND ECMWF WERE COMPLETELY DIFFERENT IN
THEIR SOLUTIONS YESTERDAY. HOWEVER...BOTH MODELS TRENDED TOWARD
EACH OTHER TODAY AND HAVE RATHER SIMILAR SOLUTIONS. WOULD LIKE TO
SEE RUN OR TWO OF CONSISTENCY BUT BASED ON LATEST SOLUTIONS IT
WOULD WARM BOTH THURSDAY AND FRIDAY WITH A FLATTENING RIDGE OVER
THE NORTHERN ROCKIES PRODUCING DOWNSLOPE WARMING. INTO THE WEEKEND
THE MODELS SUGGEST A FAST MOVING BUT RELATIVELY WEAK WAVE MOVING
ACROSS THE AREA...SO NO BIG HAZARDOUS WEATHER THREAT EXPECTED AT
THIS TIME.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 234 PM MST FRI NOV 21 2014

AVIATION CONCERNS TO MAINLY FOCUS ON WINDS LATE TONIGHT AND INTO
TOMORROW AND SNOW WHICH WILL DEVELOP OVER THE MOUNTAINS TOMORROW
AFTERNOON. STRONG WINDS WITH FREQUENT GUSTS TO 50 KT AND GREATER
WILL DEVELOP IN THE ARLINGTON AREA AND INTO THE BORDEAUX AREA LATE
TONIGHT. THESE STRONG WEST TO SOUTHWEST WINDS WILL THEN SPREAD
INTO THE SOUTHERN AND NORTHERN LARAMIE RANGES TOWARD SUNRISE
SATURDAY. GUSTY WINDS WILL ALSO SPREAD INTO LOWER ELEVATIONS AND
INTO THE PLAINS OF SOUTHEAST WYOMING SATURDAY AFTERNOON WITH GUSTS
OF 30 TO 40 KT BEING COMMON. WINDS WILL NOT BE AS STRONG INTO THE
NEBRASKA PANHANDLE BUT STILL BREEZY TO WINDY SATURDAY AFTERNOON.

MOUNTAINS WILL BE OBSCURED DUE TO FALLING AND BLOWING SNOW
SATURDAY AFTERNOON...ESPECIALLY INTO THE SNOWY AND SIERRA MADRE
RANGES WHERE A WINTER STORM WATCH IS CURRENTLY IN EFFECT. PERIODS
OF SNOW WILL CONTINUE INTO MONDAY ACROSS THESE MOUNTAINS.

STRONG NORTHWEST WINDS EXPECTED OVER THE NEBRASKA PANHANDLE SUNDAY
WITH STRONGER WINDS ALSO POSSIBLE INTO SOUTHEAST WYOMING.


&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WARNING FROM 2 AM SATURDAY TO 5 AM MST SUNDAY FOR
     WYZ103>106-110-116-117.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH LATE SATURDAY
     NIGHT FOR WYZ101-107-115-118.

NE...NONE.
&&

$$

UPDATE...MJ
SHORT TERM...CLH
LONG TERM...SML
AVIATION...SML
FIRE WEATHER...RJM



000
FXUS65 KCYS 220407
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
907 PM MST FRI NOV 21 2014

.UPDATE...
ISSUED AT 906 PM MST FRI NOV 21 2014

H25-H50 WIND/HEIGHT SHOWED THE LEADING EDGE OF 90KT JET MAXIMA
MOVING ACROSS ID/WESTERN MT...AND WILL PROGRESS EASTWARD INTO WY
OVERNIGHT. COUPLED WITH H70-H85 GEOPOTENTIAL HEIGHT GRADIENTS FROM
CRAIG-CASPER EXCEEDING 60M...EXPECT HIGH WIND CRITERIA TO BE MET
IN THE ARLINGTON/BORDEAUX AREAS BETWEEN 09Z AND 12Z SAT. MOIST
ENERGETIC FLOW STILL FORECAST TO AFFECT AREAS WEST OF THE LARAMIE
RANGE BEGINNING SAT AFTERNOON. NO CHANGES PLANNED TO THE HIGH
WIND/WINTER STORM HEADLINES THIS EVENING.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

QUIET WEATHER IS QUICKLY COMING TO AN END AS WE TRANSITION INTO A
VERY ACTIVE PATTERN FOR THE SHORT TERM PERIOD. HIGHLIGHTS REVOLVE
AROUND POTENTIAL FOR VERY STRONG WINDS OVER SOUTHEAST WYOMING AND
POSSIBLY WESTERN NEBRASKA...AND MOUNTAIN SNOWS. LATEST WATER VAPOR
SATELLITE LOOP SHOWS A VIGOROUS UPPER-LEVEL SHORTWAVE JUST ABOUT TO
CRASH INTO THE PACIFIC NORTHWEST THIS EVE. OBJECTIVE UPPER ANALYSIS
SHOWS A STRONG 110+ KT JET CORE OFFSHORE AT 21Z. THIS WILL BE OUR
MAJOR WEATHER MAKER OVER THE NEXT COUPLE OF DAYS AS THE SYSTEM MOVES
RAPIDLY SOUTHEAST AND STRENGTHENS. NOT EXPECTING ANYTHING MAJOR IN
THE NEAR TERM THOUGH. SHOULD BE A QUIET EVENING WITH WINDS STARTING
TO RELAX AS MIXING DWINDLES WITH THE LOSS OF AFTN HEATING. A BROAD
AREA OF SURFACE HIGH PRESSURE WILL KEEP THINGS ON THE DRY SIDE.

THINGS CHANGE QUICKLY INTO TONIGHT. THE NAM H85 CAG-CPR GRADIENT IS
PROGGED TO CLIMB ABOVE 60 METERS BY ABOUT 09Z SAT. MODELED LOW
LEVEL FLOW IS IMPRESSIVE TO SAY THE LEAST WITH AN EXTENSIVE CORE
OF 60 TO 70 KT WINDS BETWEEN 700 AND 800 MILLIBARS OVER A GOOD
CHUNK OF OUR WYOMING ZONES BY SUNRISE. WITH EXCELLENT SUBSIDENCE
OVER THE TRADITIONAL GAP AREAS AND GOOD 6-HR PRESSURE FALLS ON THE
ORDER OF 5-10 MB PER THE GFS...CONFIDENCE IS HIGH IN A WIDESPREAD
AND POTENTIALLY SIGNIFICANT WIND EVENT. WENT AHEAD AND UPGRADED TO
A HIGH WIND WARNING WITH ALL ZONES STARTING AT 09Z. ARL AND BRX
SHOULD HIT FIRST...WITH THE WIND CORE ALOFT SPREADING INTO THE
SOUTHERN LARAMIE RANGE/FOOTHILLS AT OR AROUND SUNRISE. ADDED THE
NORTHERN LARAMIE RANGE TO THE WARNING AS WELL AS BOTH THE GFS AND
NAM SHOW 65 KT WINDS AT H75 TO THE SOUTH OF DEER CREEK IN WESTERN
CONVERSE COUNTY. THIS MAY BE QUITE THE EVENT WITH MULTIPLE GUSTS
OVER 70 MPH. ANOTHER EVENTUAL CONCERN IS THE POTENTIAL FOR LIGHT
SNOW WEST OF THE LARAMIE RANGE LATER IN THE AFTERNOON AND EVENING.
WITH STRONG WINDS WILL COME THE POTENTIAL FOR SIGNIFICANTLY
REDUCED VISIBILITIES IN BLOWING SNOW EVEN THOUGH LOWER ELEVATIONS
SHOULD NOT SEE MUCH FOR ACCUMULATIONS. MADE IT A POINT TO MENTION
THIS IN THE NPW PRODUCT.

SOMEWHAT CONCERNED THAT SOME OF THE ADJACENT VALLEYS AND HIGH PLAINS
MAY GET IN ON SOME OF THE WINDY FUN TOMORROW AS WELL. THERE ARE SOME
KEY DIFFERENCES IN THE GFS AND NAM WHICH WILL HAVE A ROLE IN WHETHER
OR NOT WE SEE WARNING CRITERIA WINDS AT AREAS SUCH AS CHEYENNE AND
THE LARAMIE VALLEY. FORECAST SOUNDINGS FROM BOTH MODELS SHOW A BELT
OF VERY STRONG FLOW NOT FAR OFF THE SURFACE. THE DIFFERENCES ARE IN
THE MIXING. MAIN LIMITING FACTOR WILL BE CLOUD COVER...BUT BOTH THE
LOW AND MID LEVEL RH FIELDS DO NOT SUGGEST ANYTHING THICK ENOUGH.
COULD EVENTUALLY SEE AN ABUNDANCE OF LENTICULARS EAST OF THE
MOUNTAINS AS MOUNTAIN WAVE ACTIVITY BECOMES INTENSE IN THE AFTN.
IF THIS DOES NOT IMPACT SURFACE HEATING...GFS SOUNDINGS SUGGEST
50-60 KT AT THE TOP OF THE MIXED LAYER AT LARAMIE AND CHEYENNE.
THE NAM IS CONSIDERABLY LESS...HOWEVER IT DOES SHOW SUBSIDENCE IN
ITS OMEGA FIELDS SPREADING SLOWLY ONTO THE PLAINS BETWEEN 18-00Z.
DECIDED TO ISSUE A HIGH WIND WATCH FOR LOWER ELEVATIONS
IMMEDIATELY ADJACENT TO THE LARAMIE RANGE AND FOOTHILLS. EVEN IF
AFTERNOON MIXING IS NOT THE CULPRIT...MODELS ARE IN GOOD AGREEMENT
WITH A TRANSITION TO A BORA WIND EVENT ON SAT NIGHT THROUGH EARLY
SUN AS A COLD FRONT SWEEPS ACROSS THE CWA. COULD SEE WIND GUSTS
RAMP UP AGAIN FOR A FEW HOURS AROUND MIDNIGHT...WITH A FEW GUSTS
TO 60 MPH POSSIBLE OVERNIGHT.

SUNDAY WILL BE VERY WINDY OVER THE PLAINS OF SOUTHEAST WYOMING AND
THE WESTERN PANHANDLE. THE CWA WILL BE IN THE POST FRONTAL AIR MASS
AND THE MODELS SHOW A RIBBON OF 60 TO 70 KT FROM NEAR LUSK
SOUTHEAST TOWARD SIDNEY AT 00Z MON. WILL LIKELY NEED MORE WIND
HEADLINES FOR THIS TIME FRAME...BUT WILL GET THROUGH THE SATURDAY
EVENT FIRST. NOW THAT THE WIND DISCUSSION IS OUT THE WAY...ONTO
THE SNOW POTENTIAL. DIDN`T MAKE ANY CHANGES TO THE WINTER STORM
WATCH FOR THE MOUNTAINS...BUT IT STILL LOOKS GOOD. CONVEYOR BELT OF
AN UPPER JET WITH 150+ KT H25 CORE IS PROGGED TO REMAIN ANCHORED
OVER THE WESTERN US FOR SEVERAL DAYS WITH OUR MOUNTAINS REMAINING
IN THE FAVORED LEFT EXIT REGION. THIS COMBINED WITH FAVORABLE
OROGRAPHICS IN WEST-NORTHWEST FLOW AND AND SEVERAL REINFORCING
SHOTS OF 700-300 MILLIBAR MOISTURE EMBEDDED IN THE ACTIVE FLOW
ALOFT WILL SUPPORT PERIODS OF HEAVY SNOW. SHOULD SEE ONE OR TWO
FEET THROUGH MON WITH ADDITIONAL SNOW POSSIBLE IN THE DAYS
FOLLOWING. SHOULD BE PRIMARILY A MOUNTAIN EVENT WITH AREAS EAST OF
THE LARAMIE RANGE STAYING DRY IN DOWNSLOPING LOW LEVEL FLOW. MAY
SEE A FEW RAIN OR SNOW SHOWERS OVER THE NORTHERN PANHANDLE ON SUN
AFTN AS PVA OVERSPREADS THE AREA.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

BASED ON GFS/ECMWF MODEL SOLUTIONS...SHOULD SEE A BREAK IN SNOW
ACCUMULATIONS OVER SOUTHEAST WYOMING MOUNTAINS SUNDAY EVENING WITH
A SHORTWAVE RIDGE IN PLACE. THEN THE NEXT SHOT OF SNOW LIKELY TO
DEVELOP AFTER MIDNIGHT SUNDAY NIGHT. COULD SEE SOME LIGHT SNOW
INTO LOWER ELEVATIONS BUT MOST SNOW ACCUMULATIONS WILL GENERALLY
BE IN THE MOUNTAINS. VERY LITTLE CHANCE FOR ANY ACCUMULATIONS
EAST OF THE LARAMIE RANGE SUNDAY NIGHT THROUGH MONDAY. WINDS WILL
SUBSIDE ACROSS MOST OF THE AREA SUNDAY NIGHT BUT ANOTHER PUSH OF
STRONGER WINDS POSSIBLE MONDAY NIGHT AS ANOTHER STRONG UPPER LEVEL
JET MOVES OVER THE AREA. MAIN CONCERN FOR HIGH WINDS WILL BE OVER
THE FAVORED WIND PRONE LOCATIONS IN SOUTHEAST WYOMING SUCH AS
ARLINGTON...BORDEAUX AND THE SOUTHERN LARAMIE RANGE.

THE NEXT QUICK MOVING CLIPPER SYSTEM ALONG WITH THE UPPER JET
WILL BRING A CHANCE FOR LIGHT SNOW SHOWERS THROUGH TUESDAY
AFTERNOON...INCLUDING INTO THE NEBRASKA PANHANDLE. AT THIS TIME
NOT EXPECTING MUCH IN THE WAY OF SNOW ACCUMULATIONS...IF ANY. MAINLY
LOOKING FOR LIGHT SNOW SHOWERS AND FLURRIES.

UNCERTAINTY REMAINS FOR LATER PORTIONS OF THE WEEK AND HOLIDAY
WEEKEND GIVEN THE GFS AND ECMWF WERE COMPLETELY DIFFERENT IN
THEIR SOLUTIONS YESTERDAY. HOWEVER...BOTH MODELS TRENDED TOWARD
EACH OTHER TODAY AND HAVE RATHER SIMILAR SOLUTIONS. WOULD LIKE TO
SEE RUN OR TWO OF CONSISTENCY BUT BASED ON LATEST SOLUTIONS IT
WOULD WARM BOTH THURSDAY AND FRIDAY WITH A FLATTENING RIDGE OVER
THE NORTHERN ROCKIES PRODUCING DOWNSLOPE WARMING. INTO THE WEEKEND
THE MODELS SUGGEST A FAST MOVING BUT RELATIVELY WEAK WAVE MOVING
ACROSS THE AREA...SO NO BIG HAZARDOUS WEATHER THREAT EXPECTED AT
THIS TIME.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 234 PM MST FRI NOV 21 2014

AVIATION CONCERNS TO MAINLY FOCUS ON WINDS LATE TONIGHT AND INTO
TOMORROW AND SNOW WHICH WILL DEVELOP OVER THE MOUNTAINS TOMORROW
AFTERNOON. STRONG WINDS WITH FREQUENT GUSTS TO 50 KT AND GREATER
WILL DEVELOP IN THE ARLINGTON AREA AND INTO THE BORDEAUX AREA LATE
TONIGHT. THESE STRONG WEST TO SOUTHWEST WINDS WILL THEN SPREAD
INTO THE SOUTHERN AND NORTHERN LARAMIE RANGES TOWARD SUNRISE
SATURDAY. GUSTY WINDS WILL ALSO SPREAD INTO LOWER ELEVATIONS AND
INTO THE PLAINS OF SOUTHEAST WYOMING SATURDAY AFTERNOON WITH GUSTS
OF 30 TO 40 KT BEING COMMON. WINDS WILL NOT BE AS STRONG INTO THE
NEBRASKA PANHANDLE BUT STILL BREEZY TO WINDY SATURDAY AFTERNOON.

MOUNTAINS WILL BE OBSCURED DUE TO FALLING AND BLOWING SNOW
SATURDAY AFTERNOON...ESPECIALLY INTO THE SNOWY AND SIERRA MADRE
RANGES WHERE A WINTER STORM WATCH IS CURRENTLY IN EFFECT. PERIODS
OF SNOW WILL CONTINUE INTO MONDAY ACROSS THESE MOUNTAINS.

STRONG NORTHWEST WINDS EXPECTED OVER THE NEBRASKA PANHANDLE SUNDAY
WITH STRONGER WINDS ALSO POSSIBLE INTO SOUTHEAST WYOMING.


&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WARNING FROM 2 AM SATURDAY TO 5 AM MST SUNDAY FOR
     WYZ103>106-110-116-117.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH LATE SATURDAY
     NIGHT FOR WYZ101-107-115-118.

NE...NONE.
&&

$$

UPDATE...MJ
SHORT TERM...CLH
LONG TERM...SML
AVIATION...SML
FIRE WEATHER...RJM




000
FXUS65 KCYS 212245
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
345 PM MST FRI NOV 21 2014

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

QUIET WEATHER IS QUICKLY COMING TO AN END AS WE TRANSITION INTO A
VERY ACTIVE PATTERN FOR THE SHORT TERM PERIOD. HIGHLIGHTS REVOLVE
AROUND POTENTIAL FOR VERY STRONG WINDS OVER SOUTHEAST WYOMING AND
POSSIBLY WESTERN NEBRASKA...AND MOUNTAIN SNOWS. LATEST WATER VAPOR
SATELLITE LOOP SHOWS A VIGOROUS UPPER-LEVEL SHORTWAVE JUST ABOUT TO
CRASH INTO THE PACIFIC NORTHWEST THIS EVE. OBJECTIVE UPPER ANALYSIS
SHOWS A STRONG 110+ KT JET CORE OFFSHORE AT 21Z. THIS WILL BE OUR
MAJOR WEATHER MAKER OVER THE NEXT COUPLE OF DAYS AS THE SYSTEM MOVES
RAPIDLY SOUTHEAST AND STRENGTHENS. NOT EXPECTING ANYTHING MAJOR IN
THE NEAR TERM THOUGH. SHOULD BE A QUIET EVENING WITH WINDS STARTING
TO RELAX AS MIXING DWINDLES WITH THE LOSS OF AFTN HEATING. A BROAD
AREA OF SURFACE HIGH PRESSURE WILL KEEP THINGS ON THE DRY SIDE.

THINGS CHANGE QUICKLY INTO TONIGHT. THE NAM H85 CAG-CPR GRADIENT IS
PROGGED TO CLIMB ABOVE 60 METERS BY ABOUT 09Z SAT. MODELED LLVL FLOW
IS IMPRESSIVE TO SAY THE LEAST WITH AN EXTENSIVE CORE OF 60 TO 70 KT
WINDS BETWEEN 700 AND 800 MILLIBARS OVER A GOOD CHUNK OF OUR WYOMING
ZONES BY SUNRISE. WITH EXCELLENT SUBSIDENCE OVER THE TRADITIONAL GAP
AREAS AND GOOD 6-HR PRESSURE FALLS ON THE ORDER OF 5-10 MB PER THE
GFS...CONFIDENCE IS HIGH IN A WIDESPREAD AND POTENTIALLY SIGNIFICANT
WIND EVENT. WENT AHEAD AND UPGRADED TO A HIGH WIND WARNING WITH ALL
ZONES STARTING AT 09Z. ARL AND BRX SHOULD HIT FIRST...WITH THE WIND
CORE ALOFT SPREADING INTO THE SOUTHERN LARAMIE RANGE/FOOTHILLS AT OR
AROUND SUNRISE. ADDED THE NORTHERN LARAMIE RANGE TO THE WARNING AS
WELL AS BOTH THE GFS AND NAM SHOW 65 KT WINDS AT H75 TO THE SOUTH OF
DEER CREEK IN WESTERN CONVERSE COUNTY. THIS MAY BE QUITE THE EVENT
WITH MULTIPLE GUSTS OVER 70 MPH. ANOTHER EVENTUAL CONCERN IS THE
POTENTIAL FOR LIGHT SNOW WEST OF THE LARAMIE RANGE LATER IN THE
AFTERNOON AND EVENING. WITH STRONG WINDS WILL COME THE POTENTIAL FOR
SIGNIFICANTLY REDUCED VISIBILITIES IN BLOWING SNOW EVEN THOUGH LOWER
ELEVATIONS SHOULD NOT SEE MUCH FOR ACCUMULATIONS. MADE IT A POINT TO
MENTION THIS IN THE NPW PRODUCT.

SOMEWHAT CONCERNED THAT SOME OF THE ADJACENT VALLEYS AND HIGH PLAINS
MAY GET IN ON SOME OF THE WINDY FUN TOMORROW AS WELL. THERE ARE SOME
KEY DIFFERENCES IN THE GFS AND NAM WHICH WILL HAVE A ROLE IN WHETHER
OR NOT WE SEE WARNING CRITERIA WINDS AT AREAS SUCH AS CHEYENNE AND
THE LARAMIE VALLEY. FORECAST SOUNDINGS FROM BOTH MODELS SHOW A BELT
OF VERY STRONG FLOW NOT FAR OFF THE SURFACE. THE DIFFERENCES ARE IN
THE MIXING. MAIN LIMITING FACTOR WILL BE CLOUD COVER...BUT BOTH THE
LOW AND MIDLVL RH FIELDS DO NOT SUGGEST ANYTHING THICK ENOUGH. COULD
EVENTUALLY SEE AN ABUNDANCE OF LENTICULARS EAST OF THE MOUNTAINS AS
MOUNTAIN WAVE ACTIVITY BECOMES INTENSE IN THE AFTN. IF THIS DOES NOT
IMPACT SURFACE HEATING...GFS SOUNDINGS SUGGEST 50-60 KTS AT THE TOP
OF THE MIXED LAYER AT LARAMIE AND CHEYENNE. THE NAM IS CONSIDERABLY
LESS...HOWEVER IT DOES SHOW SUBSIDENCE IN ITS OMEGA FIELDS SPREADING
SLOWLY ONTO THE PLAINS BETWEEN 18-00Z. DECIDED TO ISSUE A HIGH WIND
WATCH FOR LOWER ELEVATIONS IMMEDIATELY ADJACENT TO THE LARAMIE RANGE
AND FOOTHILLS. EVEN IF AFTERNOON MIXING IS NOT THE CULPRIT...MODELS
ARE IN GOOD AGREEMENT WITH A TRANSITION TO A BORA WIND EVENT ON SAT
NIGHT THROUGH EARLY SUN AS A COLD FRONT SWEEPS ACROSS THE CWA. COULD
SEE WIND GUSTS RAMP UP AGAIN FOR A FEW HOURS AROUND MIDNIGHT...WITH
A FEW GUSTS TO 60 MPH POSSIBLE OVERNIGHT.

SUNDAY WILL BE VERY WINDY OVER THE PLAINS OF SOUTHEAST WYOMING AND
THE WESTERN PANHANDLE. THE CWA WILL BE IN THE POST FRONTAL AIR MASS
AND THE MODELS SHOW A RIBBON OF 60 TO 70 KTS FROM NEAR LSK SOUTHEAST
TOWARD SNY AT 00Z MON. WILL LIKELY NEED MORE WIND HEADLINES FOR THIS
TIME FRAME...BUT WILL GET THROUGH THE SATURDAY EVENT FIRST. NOW THAT
THE WIND DISCUSSION IS OUT THE WAY...ONTO THE SNOW POTENTIAL. DIDNT
MAKE ANY CHANGES TO THE WINTER STORM WATCH FOR THE MOUNTAINS...BUT
IT STILL LOOKS GOOD. FIREHOSE OF AN UPPER JET WITH 150+ KT H25 CORE
IS PROGGED TO REMAIN ANCHORED OVER THE WESTERN US FOR SEVERAL DAYS
WITH OUR MOUNTAINS REMAINING IN THE FAVORED LEFT EXIT REGION. THIS
COMBINED WITH FAVORABLE OROGRAPHICS IN WEST-NORTHWEST FLOW AND AND
SEVERAL REINFORCING SHOTS OF 700-300 MILLIBAR MOISTURE EMBEDDED IN
THE ACTIVE FLOW ALOFT WILL SUPPORT PERIODS OF HEAVY SNOW. SHOULD SEE
ONE OR TWO FEET THROUGH MON WITH ADDITIONAL SNOW POSSIBLE IN THE
DAYS FOLLOWING. SHOULD BE PRIMARILY A MOUNTAIN EVENT WITH AREAS EAST
OF THE LARAMIE RANGE STAYING DRY IN DOWNSLOPING LLVL FLOW. MAY SEE A
FEW RAIN OR SNOW SHOWERS OVER THE NORTHERN PANHANDLE ON SUN AFTN AS
PVA OVERSPREADS THE AREA.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

BASED ON GFS/ECMWF MODEL SOLUTIONS...SHOULD SEE A BREAK IN SNOW
ACCUMULATIONS OVER SOUTHEAST WYOMING MOUNTAINS SUNDAY EVENING WITH
A SHORTWAVE RIDGE IN PLACE. THEN THE NEXT SHOT OF SNOW LIKELY TO
DEVELOP AFTER MIDNIGHT SUNDAY NIGHT. COULD SEE SOME LIGHT SNOW
INTO LOWER ELEVATIONS BUT MOST SNOW ACCUMULATIONS WILL GENERALLY
BE IN THE MOUNTAINS. VERY LITTLE CHANCE FOR ANY ACCUMULATIONS
EAST OF THE LARAMIE RANGE SUNDAY NIGHT THROUGH MONDAY. WINDS WILL
SUBSIDE ACROSS MOST OF THE AREA SUNDAY NIGHT BUT ANOTHER PUSH OF
STRONGER WINDS POSSIBLE MONDAY NIGHT AS ANOTHER STRONG UPPER LEVEL
JET MOVES OVER THE AREA. MAIN CONCERN FOR HIGH WINDS WILL BE OVER
THE FAVORED WIND PRONE LOCATIONS IN SOUTHEAST WYOMING SUCH AS
ARLINGTON...BORDEAUX AND THE SOUTHERN LARAMIE RANGE.

THE NEXT QUICK MOVING CLIPPER SYSTEM ALONG WITH THE UPPER JET
WILL BRING A CHANCE FOR LIGHT SNOW SHOWERS THROUGH TUESDAY
AFTERNOON...INCLUDING INTO THE NEBRASKA PANHANDLE. AT THIS TIME
NOT EXPECTING MUCH IN THE WAY OF SNOW ACCUMULATIONS...IF ANY. MAINLY
LOOKING FOR LIGHT SNOW SHOWERS AND FLURRIES.

UNCERTAINTLY REMAINS FOR LATER PORTIONS OF THE WEEK AND HOLIDAY
WEEKEND GIVEN THE GFS AND ECMFW WERE COMPLETELY DIFFERENT IN
THEIR SOLUTIONS YESTERDAY. HOWEVER...BOTH MODLES TRENDED TOWARD
EACH OTHER TODAY AND HAVE RATHER SIMILAR SOLUTIONS. WOULD LIKE TO
SEE RUN OR TWO OF CONSISTENCY BUT BASED ON LATEST SOLUTIONS IT
WOULD WARM BOTH THURSDAY AND FRIDAY WITH A FLATTENING RIDGE OVER
THE NORTHERN ROCKIES PRODUCING DOWNSLOPE WARMING. INTO THE
WEEKEND THE MODLES SUGGEST A FAST MOVING BUT RELATIVELY WEAK WAVE
MOVING ACROSS THE AREA...SO NO BIG HAZARDOUS WEATHER THREAT
EXPECTED AT THIS TIME.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 234 PM MST FRI NOV 21 2014

AVIATION CONCERNS TO MAINLY FOCUS ON WINDS LATE TONIGHT AND INTO
TOMORROW AND SNOW WHICH WILL DEVELOP OVER THE MOUNTAINS TOMORROW
AFTERNOON. STRONG WINDS WITH FREQUENT GUSTS TO 50 KTS AND GREATER
WILL DEVELOP IN THE ARLINGTON AREA AND INTO THE BORDEAUX AREA
LATE TONIGHT. THESE STRONG WEST TO SOUTHWEST WINDS WILL THEN
SPREAD INTO THE SOUTHERN AND NORTHERN LARAMIE RANGES TOWARD
SUNRISE SATURDAY. GUSTY WINDS WILL ALSO SPREAD INTO LOWER
ELEVATIONS AND INTO THE PLAINS OF SOUTHEAST WYOMING SATURDAY
AFTERNOON WITH GUSTS OF 30 TO 40 KTS BEING COMMON. WINDS WILL NOT
BE AS STRONG INTO THE NEBRASKA PANHANDLE BUT STILL BREEZY TO WINDY
SATURDAY AFTERNOON.

MOUNTAINS WILL BE OBSCURED DUE TO FALLING AND BLOWING SNOW
SATURDAY AFTERNOON...ESPECIALLY INTO THE SNOWY AND SIERRA MADRE
RANGES WHERE A WINTER STORM WATCH IS CURRENTLY IN EFFECT. PERIODS
OF SNOW WILL CONTINUE INTO MONDAY ACROSS THESE MOUNTAINS.

STRONG NORTHWEST WINDS EXPECTED OVER THE NEBRASKA PANHANDLE SUNDAY
WITH STRONGER WINDS ALSO POSSIBLE INTO SOUTHEAST WYOMING.

&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WARNING FROM 2 AM SATURDAY TO 5 AM MST SUNDAY FOR
     WYZ103>106-110-116-117.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH LATE SATURDAY
     NIGHT FOR WYZ101-107-115-118.

NE...NONE.

&&

$$

SHORT TERM...CLH
LONG TERM...SML
AVIATION...SML
FIRE WEATHER...RJM



000
FXUS65 KCYS 212245
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
345 PM MST FRI NOV 21 2014

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

QUIET WEATHER IS QUICKLY COMING TO AN END AS WE TRANSITION INTO A
VERY ACTIVE PATTERN FOR THE SHORT TERM PERIOD. HIGHLIGHTS REVOLVE
AROUND POTENTIAL FOR VERY STRONG WINDS OVER SOUTHEAST WYOMING AND
POSSIBLY WESTERN NEBRASKA...AND MOUNTAIN SNOWS. LATEST WATER VAPOR
SATELLITE LOOP SHOWS A VIGOROUS UPPER-LEVEL SHORTWAVE JUST ABOUT TO
CRASH INTO THE PACIFIC NORTHWEST THIS EVE. OBJECTIVE UPPER ANALYSIS
SHOWS A STRONG 110+ KT JET CORE OFFSHORE AT 21Z. THIS WILL BE OUR
MAJOR WEATHER MAKER OVER THE NEXT COUPLE OF DAYS AS THE SYSTEM MOVES
RAPIDLY SOUTHEAST AND STRENGTHENS. NOT EXPECTING ANYTHING MAJOR IN
THE NEAR TERM THOUGH. SHOULD BE A QUIET EVENING WITH WINDS STARTING
TO RELAX AS MIXING DWINDLES WITH THE LOSS OF AFTN HEATING. A BROAD
AREA OF SURFACE HIGH PRESSURE WILL KEEP THINGS ON THE DRY SIDE.

THINGS CHANGE QUICKLY INTO TONIGHT. THE NAM H85 CAG-CPR GRADIENT IS
PROGGED TO CLIMB ABOVE 60 METERS BY ABOUT 09Z SAT. MODELED LLVL FLOW
IS IMPRESSIVE TO SAY THE LEAST WITH AN EXTENSIVE CORE OF 60 TO 70 KT
WINDS BETWEEN 700 AND 800 MILLIBARS OVER A GOOD CHUNK OF OUR WYOMING
ZONES BY SUNRISE. WITH EXCELLENT SUBSIDENCE OVER THE TRADITIONAL GAP
AREAS AND GOOD 6-HR PRESSURE FALLS ON THE ORDER OF 5-10 MB PER THE
GFS...CONFIDENCE IS HIGH IN A WIDESPREAD AND POTENTIALLY SIGNIFICANT
WIND EVENT. WENT AHEAD AND UPGRADED TO A HIGH WIND WARNING WITH ALL
ZONES STARTING AT 09Z. ARL AND BRX SHOULD HIT FIRST...WITH THE WIND
CORE ALOFT SPREADING INTO THE SOUTHERN LARAMIE RANGE/FOOTHILLS AT OR
AROUND SUNRISE. ADDED THE NORTHERN LARAMIE RANGE TO THE WARNING AS
WELL AS BOTH THE GFS AND NAM SHOW 65 KT WINDS AT H75 TO THE SOUTH OF
DEER CREEK IN WESTERN CONVERSE COUNTY. THIS MAY BE QUITE THE EVENT
WITH MULTIPLE GUSTS OVER 70 MPH. ANOTHER EVENTUAL CONCERN IS THE
POTENTIAL FOR LIGHT SNOW WEST OF THE LARAMIE RANGE LATER IN THE
AFTERNOON AND EVENING. WITH STRONG WINDS WILL COME THE POTENTIAL FOR
SIGNIFICANTLY REDUCED VISIBILITIES IN BLOWING SNOW EVEN THOUGH LOWER
ELEVATIONS SHOULD NOT SEE MUCH FOR ACCUMULATIONS. MADE IT A POINT TO
MENTION THIS IN THE NPW PRODUCT.

SOMEWHAT CONCERNED THAT SOME OF THE ADJACENT VALLEYS AND HIGH PLAINS
MAY GET IN ON SOME OF THE WINDY FUN TOMORROW AS WELL. THERE ARE SOME
KEY DIFFERENCES IN THE GFS AND NAM WHICH WILL HAVE A ROLE IN WHETHER
OR NOT WE SEE WARNING CRITERIA WINDS AT AREAS SUCH AS CHEYENNE AND
THE LARAMIE VALLEY. FORECAST SOUNDINGS FROM BOTH MODELS SHOW A BELT
OF VERY STRONG FLOW NOT FAR OFF THE SURFACE. THE DIFFERENCES ARE IN
THE MIXING. MAIN LIMITING FACTOR WILL BE CLOUD COVER...BUT BOTH THE
LOW AND MIDLVL RH FIELDS DO NOT SUGGEST ANYTHING THICK ENOUGH. COULD
EVENTUALLY SEE AN ABUNDANCE OF LENTICULARS EAST OF THE MOUNTAINS AS
MOUNTAIN WAVE ACTIVITY BECOMES INTENSE IN THE AFTN. IF THIS DOES NOT
IMPACT SURFACE HEATING...GFS SOUNDINGS SUGGEST 50-60 KTS AT THE TOP
OF THE MIXED LAYER AT LARAMIE AND CHEYENNE. THE NAM IS CONSIDERABLY
LESS...HOWEVER IT DOES SHOW SUBSIDENCE IN ITS OMEGA FIELDS SPREADING
SLOWLY ONTO THE PLAINS BETWEEN 18-00Z. DECIDED TO ISSUE A HIGH WIND
WATCH FOR LOWER ELEVATIONS IMMEDIATELY ADJACENT TO THE LARAMIE RANGE
AND FOOTHILLS. EVEN IF AFTERNOON MIXING IS NOT THE CULPRIT...MODELS
ARE IN GOOD AGREEMENT WITH A TRANSITION TO A BORA WIND EVENT ON SAT
NIGHT THROUGH EARLY SUN AS A COLD FRONT SWEEPS ACROSS THE CWA. COULD
SEE WIND GUSTS RAMP UP AGAIN FOR A FEW HOURS AROUND MIDNIGHT...WITH
A FEW GUSTS TO 60 MPH POSSIBLE OVERNIGHT.

SUNDAY WILL BE VERY WINDY OVER THE PLAINS OF SOUTHEAST WYOMING AND
THE WESTERN PANHANDLE. THE CWA WILL BE IN THE POST FRONTAL AIR MASS
AND THE MODELS SHOW A RIBBON OF 60 TO 70 KTS FROM NEAR LSK SOUTHEAST
TOWARD SNY AT 00Z MON. WILL LIKELY NEED MORE WIND HEADLINES FOR THIS
TIME FRAME...BUT WILL GET THROUGH THE SATURDAY EVENT FIRST. NOW THAT
THE WIND DISCUSSION IS OUT THE WAY...ONTO THE SNOW POTENTIAL. DIDNT
MAKE ANY CHANGES TO THE WINTER STORM WATCH FOR THE MOUNTAINS...BUT
IT STILL LOOKS GOOD. FIREHOSE OF AN UPPER JET WITH 150+ KT H25 CORE
IS PROGGED TO REMAIN ANCHORED OVER THE WESTERN US FOR SEVERAL DAYS
WITH OUR MOUNTAINS REMAINING IN THE FAVORED LEFT EXIT REGION. THIS
COMBINED WITH FAVORABLE OROGRAPHICS IN WEST-NORTHWEST FLOW AND AND
SEVERAL REINFORCING SHOTS OF 700-300 MILLIBAR MOISTURE EMBEDDED IN
THE ACTIVE FLOW ALOFT WILL SUPPORT PERIODS OF HEAVY SNOW. SHOULD SEE
ONE OR TWO FEET THROUGH MON WITH ADDITIONAL SNOW POSSIBLE IN THE
DAYS FOLLOWING. SHOULD BE PRIMARILY A MOUNTAIN EVENT WITH AREAS EAST
OF THE LARAMIE RANGE STAYING DRY IN DOWNSLOPING LLVL FLOW. MAY SEE A
FEW RAIN OR SNOW SHOWERS OVER THE NORTHERN PANHANDLE ON SUN AFTN AS
PVA OVERSPREADS THE AREA.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

BASED ON GFS/ECMWF MODEL SOLUTIONS...SHOULD SEE A BREAK IN SNOW
ACCUMULATIONS OVER SOUTHEAST WYOMING MOUNTAINS SUNDAY EVENING WITH
A SHORTWAVE RIDGE IN PLACE. THEN THE NEXT SHOT OF SNOW LIKELY TO
DEVELOP AFTER MIDNIGHT SUNDAY NIGHT. COULD SEE SOME LIGHT SNOW
INTO LOWER ELEVATIONS BUT MOST SNOW ACCUMULATIONS WILL GENERALLY
BE IN THE MOUNTAINS. VERY LITTLE CHANCE FOR ANY ACCUMULATIONS
EAST OF THE LARAMIE RANGE SUNDAY NIGHT THROUGH MONDAY. WINDS WILL
SUBSIDE ACROSS MOST OF THE AREA SUNDAY NIGHT BUT ANOTHER PUSH OF
STRONGER WINDS POSSIBLE MONDAY NIGHT AS ANOTHER STRONG UPPER LEVEL
JET MOVES OVER THE AREA. MAIN CONCERN FOR HIGH WINDS WILL BE OVER
THE FAVORED WIND PRONE LOCATIONS IN SOUTHEAST WYOMING SUCH AS
ARLINGTON...BORDEAUX AND THE SOUTHERN LARAMIE RANGE.

THE NEXT QUICK MOVING CLIPPER SYSTEM ALONG WITH THE UPPER JET
WILL BRING A CHANCE FOR LIGHT SNOW SHOWERS THROUGH TUESDAY
AFTERNOON...INCLUDING INTO THE NEBRASKA PANHANDLE. AT THIS TIME
NOT EXPECTING MUCH IN THE WAY OF SNOW ACCUMULATIONS...IF ANY. MAINLY
LOOKING FOR LIGHT SNOW SHOWERS AND FLURRIES.

UNCERTAINTLY REMAINS FOR LATER PORTIONS OF THE WEEK AND HOLIDAY
WEEKEND GIVEN THE GFS AND ECMFW WERE COMPLETELY DIFFERENT IN
THEIR SOLUTIONS YESTERDAY. HOWEVER...BOTH MODLES TRENDED TOWARD
EACH OTHER TODAY AND HAVE RATHER SIMILAR SOLUTIONS. WOULD LIKE TO
SEE RUN OR TWO OF CONSISTENCY BUT BASED ON LATEST SOLUTIONS IT
WOULD WARM BOTH THURSDAY AND FRIDAY WITH A FLATTENING RIDGE OVER
THE NORTHERN ROCKIES PRODUCING DOWNSLOPE WARMING. INTO THE
WEEKEND THE MODLES SUGGEST A FAST MOVING BUT RELATIVELY WEAK WAVE
MOVING ACROSS THE AREA...SO NO BIG HAZARDOUS WEATHER THREAT
EXPECTED AT THIS TIME.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 234 PM MST FRI NOV 21 2014

AVIATION CONCERNS TO MAINLY FOCUS ON WINDS LATE TONIGHT AND INTO
TOMORROW AND SNOW WHICH WILL DEVELOP OVER THE MOUNTAINS TOMORROW
AFTERNOON. STRONG WINDS WITH FREQUENT GUSTS TO 50 KTS AND GREATER
WILL DEVELOP IN THE ARLINGTON AREA AND INTO THE BORDEAUX AREA
LATE TONIGHT. THESE STRONG WEST TO SOUTHWEST WINDS WILL THEN
SPREAD INTO THE SOUTHERN AND NORTHERN LARAMIE RANGES TOWARD
SUNRISE SATURDAY. GUSTY WINDS WILL ALSO SPREAD INTO LOWER
ELEVATIONS AND INTO THE PLAINS OF SOUTHEAST WYOMING SATURDAY
AFTERNOON WITH GUSTS OF 30 TO 40 KTS BEING COMMON. WINDS WILL NOT
BE AS STRONG INTO THE NEBRASKA PANHANDLE BUT STILL BREEZY TO WINDY
SATURDAY AFTERNOON.

MOUNTAINS WILL BE OBSCURED DUE TO FALLING AND BLOWING SNOW
SATURDAY AFTERNOON...ESPECIALLY INTO THE SNOWY AND SIERRA MADRE
RANGES WHERE A WINTER STORM WATCH IS CURRENTLY IN EFFECT. PERIODS
OF SNOW WILL CONTINUE INTO MONDAY ACROSS THESE MOUNTAINS.

STRONG NORTHWEST WINDS EXPECTED OVER THE NEBRASKA PANHANDLE SUNDAY
WITH STRONGER WINDS ALSO POSSIBLE INTO SOUTHEAST WYOMING.

&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WARNING FROM 2 AM SATURDAY TO 5 AM MST SUNDAY FOR
     WYZ103>106-110-116-117.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH LATE SATURDAY
     NIGHT FOR WYZ101-107-115-118.

NE...NONE.

&&

$$

SHORT TERM...CLH
LONG TERM...SML
AVIATION...SML
FIRE WEATHER...RJM




000
FXUS65 KCYS 212245
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
345 PM MST FRI NOV 21 2014

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

QUIET WEATHER IS QUICKLY COMING TO AN END AS WE TRANSITION INTO A
VERY ACTIVE PATTERN FOR THE SHORT TERM PERIOD. HIGHLIGHTS REVOLVE
AROUND POTENTIAL FOR VERY STRONG WINDS OVER SOUTHEAST WYOMING AND
POSSIBLY WESTERN NEBRASKA...AND MOUNTAIN SNOWS. LATEST WATER VAPOR
SATELLITE LOOP SHOWS A VIGOROUS UPPER-LEVEL SHORTWAVE JUST ABOUT TO
CRASH INTO THE PACIFIC NORTHWEST THIS EVE. OBJECTIVE UPPER ANALYSIS
SHOWS A STRONG 110+ KT JET CORE OFFSHORE AT 21Z. THIS WILL BE OUR
MAJOR WEATHER MAKER OVER THE NEXT COUPLE OF DAYS AS THE SYSTEM MOVES
RAPIDLY SOUTHEAST AND STRENGTHENS. NOT EXPECTING ANYTHING MAJOR IN
THE NEAR TERM THOUGH. SHOULD BE A QUIET EVENING WITH WINDS STARTING
TO RELAX AS MIXING DWINDLES WITH THE LOSS OF AFTN HEATING. A BROAD
AREA OF SURFACE HIGH PRESSURE WILL KEEP THINGS ON THE DRY SIDE.

THINGS CHANGE QUICKLY INTO TONIGHT. THE NAM H85 CAG-CPR GRADIENT IS
PROGGED TO CLIMB ABOVE 60 METERS BY ABOUT 09Z SAT. MODELED LLVL FLOW
IS IMPRESSIVE TO SAY THE LEAST WITH AN EXTENSIVE CORE OF 60 TO 70 KT
WINDS BETWEEN 700 AND 800 MILLIBARS OVER A GOOD CHUNK OF OUR WYOMING
ZONES BY SUNRISE. WITH EXCELLENT SUBSIDENCE OVER THE TRADITIONAL GAP
AREAS AND GOOD 6-HR PRESSURE FALLS ON THE ORDER OF 5-10 MB PER THE
GFS...CONFIDENCE IS HIGH IN A WIDESPREAD AND POTENTIALLY SIGNIFICANT
WIND EVENT. WENT AHEAD AND UPGRADED TO A HIGH WIND WARNING WITH ALL
ZONES STARTING AT 09Z. ARL AND BRX SHOULD HIT FIRST...WITH THE WIND
CORE ALOFT SPREADING INTO THE SOUTHERN LARAMIE RANGE/FOOTHILLS AT OR
AROUND SUNRISE. ADDED THE NORTHERN LARAMIE RANGE TO THE WARNING AS
WELL AS BOTH THE GFS AND NAM SHOW 65 KT WINDS AT H75 TO THE SOUTH OF
DEER CREEK IN WESTERN CONVERSE COUNTY. THIS MAY BE QUITE THE EVENT
WITH MULTIPLE GUSTS OVER 70 MPH. ANOTHER EVENTUAL CONCERN IS THE
POTENTIAL FOR LIGHT SNOW WEST OF THE LARAMIE RANGE LATER IN THE
AFTERNOON AND EVENING. WITH STRONG WINDS WILL COME THE POTENTIAL FOR
SIGNIFICANTLY REDUCED VISIBILITIES IN BLOWING SNOW EVEN THOUGH LOWER
ELEVATIONS SHOULD NOT SEE MUCH FOR ACCUMULATIONS. MADE IT A POINT TO
MENTION THIS IN THE NPW PRODUCT.

SOMEWHAT CONCERNED THAT SOME OF THE ADJACENT VALLEYS AND HIGH PLAINS
MAY GET IN ON SOME OF THE WINDY FUN TOMORROW AS WELL. THERE ARE SOME
KEY DIFFERENCES IN THE GFS AND NAM WHICH WILL HAVE A ROLE IN WHETHER
OR NOT WE SEE WARNING CRITERIA WINDS AT AREAS SUCH AS CHEYENNE AND
THE LARAMIE VALLEY. FORECAST SOUNDINGS FROM BOTH MODELS SHOW A BELT
OF VERY STRONG FLOW NOT FAR OFF THE SURFACE. THE DIFFERENCES ARE IN
THE MIXING. MAIN LIMITING FACTOR WILL BE CLOUD COVER...BUT BOTH THE
LOW AND MIDLVL RH FIELDS DO NOT SUGGEST ANYTHING THICK ENOUGH. COULD
EVENTUALLY SEE AN ABUNDANCE OF LENTICULARS EAST OF THE MOUNTAINS AS
MOUNTAIN WAVE ACTIVITY BECOMES INTENSE IN THE AFTN. IF THIS DOES NOT
IMPACT SURFACE HEATING...GFS SOUNDINGS SUGGEST 50-60 KTS AT THE TOP
OF THE MIXED LAYER AT LARAMIE AND CHEYENNE. THE NAM IS CONSIDERABLY
LESS...HOWEVER IT DOES SHOW SUBSIDENCE IN ITS OMEGA FIELDS SPREADING
SLOWLY ONTO THE PLAINS BETWEEN 18-00Z. DECIDED TO ISSUE A HIGH WIND
WATCH FOR LOWER ELEVATIONS IMMEDIATELY ADJACENT TO THE LARAMIE RANGE
AND FOOTHILLS. EVEN IF AFTERNOON MIXING IS NOT THE CULPRIT...MODELS
ARE IN GOOD AGREEMENT WITH A TRANSITION TO A BORA WIND EVENT ON SAT
NIGHT THROUGH EARLY SUN AS A COLD FRONT SWEEPS ACROSS THE CWA. COULD
SEE WIND GUSTS RAMP UP AGAIN FOR A FEW HOURS AROUND MIDNIGHT...WITH
A FEW GUSTS TO 60 MPH POSSIBLE OVERNIGHT.

SUNDAY WILL BE VERY WINDY OVER THE PLAINS OF SOUTHEAST WYOMING AND
THE WESTERN PANHANDLE. THE CWA WILL BE IN THE POST FRONTAL AIR MASS
AND THE MODELS SHOW A RIBBON OF 60 TO 70 KTS FROM NEAR LSK SOUTHEAST
TOWARD SNY AT 00Z MON. WILL LIKELY NEED MORE WIND HEADLINES FOR THIS
TIME FRAME...BUT WILL GET THROUGH THE SATURDAY EVENT FIRST. NOW THAT
THE WIND DISCUSSION IS OUT THE WAY...ONTO THE SNOW POTENTIAL. DIDNT
MAKE ANY CHANGES TO THE WINTER STORM WATCH FOR THE MOUNTAINS...BUT
IT STILL LOOKS GOOD. FIREHOSE OF AN UPPER JET WITH 150+ KT H25 CORE
IS PROGGED TO REMAIN ANCHORED OVER THE WESTERN US FOR SEVERAL DAYS
WITH OUR MOUNTAINS REMAINING IN THE FAVORED LEFT EXIT REGION. THIS
COMBINED WITH FAVORABLE OROGRAPHICS IN WEST-NORTHWEST FLOW AND AND
SEVERAL REINFORCING SHOTS OF 700-300 MILLIBAR MOISTURE EMBEDDED IN
THE ACTIVE FLOW ALOFT WILL SUPPORT PERIODS OF HEAVY SNOW. SHOULD SEE
ONE OR TWO FEET THROUGH MON WITH ADDITIONAL SNOW POSSIBLE IN THE
DAYS FOLLOWING. SHOULD BE PRIMARILY A MOUNTAIN EVENT WITH AREAS EAST
OF THE LARAMIE RANGE STAYING DRY IN DOWNSLOPING LLVL FLOW. MAY SEE A
FEW RAIN OR SNOW SHOWERS OVER THE NORTHERN PANHANDLE ON SUN AFTN AS
PVA OVERSPREADS THE AREA.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

BASED ON GFS/ECMWF MODEL SOLUTIONS...SHOULD SEE A BREAK IN SNOW
ACCUMULATIONS OVER SOUTHEAST WYOMING MOUNTAINS SUNDAY EVENING WITH
A SHORTWAVE RIDGE IN PLACE. THEN THE NEXT SHOT OF SNOW LIKELY TO
DEVELOP AFTER MIDNIGHT SUNDAY NIGHT. COULD SEE SOME LIGHT SNOW
INTO LOWER ELEVATIONS BUT MOST SNOW ACCUMULATIONS WILL GENERALLY
BE IN THE MOUNTAINS. VERY LITTLE CHANCE FOR ANY ACCUMULATIONS
EAST OF THE LARAMIE RANGE SUNDAY NIGHT THROUGH MONDAY. WINDS WILL
SUBSIDE ACROSS MOST OF THE AREA SUNDAY NIGHT BUT ANOTHER PUSH OF
STRONGER WINDS POSSIBLE MONDAY NIGHT AS ANOTHER STRONG UPPER LEVEL
JET MOVES OVER THE AREA. MAIN CONCERN FOR HIGH WINDS WILL BE OVER
THE FAVORED WIND PRONE LOCATIONS IN SOUTHEAST WYOMING SUCH AS
ARLINGTON...BORDEAUX AND THE SOUTHERN LARAMIE RANGE.

THE NEXT QUICK MOVING CLIPPER SYSTEM ALONG WITH THE UPPER JET
WILL BRING A CHANCE FOR LIGHT SNOW SHOWERS THROUGH TUESDAY
AFTERNOON...INCLUDING INTO THE NEBRASKA PANHANDLE. AT THIS TIME
NOT EXPECTING MUCH IN THE WAY OF SNOW ACCUMULATIONS...IF ANY. MAINLY
LOOKING FOR LIGHT SNOW SHOWERS AND FLURRIES.

UNCERTAINTLY REMAINS FOR LATER PORTIONS OF THE WEEK AND HOLIDAY
WEEKEND GIVEN THE GFS AND ECMFW WERE COMPLETELY DIFFERENT IN
THEIR SOLUTIONS YESTERDAY. HOWEVER...BOTH MODLES TRENDED TOWARD
EACH OTHER TODAY AND HAVE RATHER SIMILAR SOLUTIONS. WOULD LIKE TO
SEE RUN OR TWO OF CONSISTENCY BUT BASED ON LATEST SOLUTIONS IT
WOULD WARM BOTH THURSDAY AND FRIDAY WITH A FLATTENING RIDGE OVER
THE NORTHERN ROCKIES PRODUCING DOWNSLOPE WARMING. INTO THE
WEEKEND THE MODLES SUGGEST A FAST MOVING BUT RELATIVELY WEAK WAVE
MOVING ACROSS THE AREA...SO NO BIG HAZARDOUS WEATHER THREAT
EXPECTED AT THIS TIME.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 234 PM MST FRI NOV 21 2014

AVIATION CONCERNS TO MAINLY FOCUS ON WINDS LATE TONIGHT AND INTO
TOMORROW AND SNOW WHICH WILL DEVELOP OVER THE MOUNTAINS TOMORROW
AFTERNOON. STRONG WINDS WITH FREQUENT GUSTS TO 50 KTS AND GREATER
WILL DEVELOP IN THE ARLINGTON AREA AND INTO THE BORDEAUX AREA
LATE TONIGHT. THESE STRONG WEST TO SOUTHWEST WINDS WILL THEN
SPREAD INTO THE SOUTHERN AND NORTHERN LARAMIE RANGES TOWARD
SUNRISE SATURDAY. GUSTY WINDS WILL ALSO SPREAD INTO LOWER
ELEVATIONS AND INTO THE PLAINS OF SOUTHEAST WYOMING SATURDAY
AFTERNOON WITH GUSTS OF 30 TO 40 KTS BEING COMMON. WINDS WILL NOT
BE AS STRONG INTO THE NEBRASKA PANHANDLE BUT STILL BREEZY TO WINDY
SATURDAY AFTERNOON.

MOUNTAINS WILL BE OBSCURED DUE TO FALLING AND BLOWING SNOW
SATURDAY AFTERNOON...ESPECIALLY INTO THE SNOWY AND SIERRA MADRE
RANGES WHERE A WINTER STORM WATCH IS CURRENTLY IN EFFECT. PERIODS
OF SNOW WILL CONTINUE INTO MONDAY ACROSS THESE MOUNTAINS.

STRONG NORTHWEST WINDS EXPECTED OVER THE NEBRASKA PANHANDLE SUNDAY
WITH STRONGER WINDS ALSO POSSIBLE INTO SOUTHEAST WYOMING.

&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WARNING FROM 2 AM SATURDAY TO 5 AM MST SUNDAY FOR
     WYZ103>106-110-116-117.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH LATE SATURDAY
     NIGHT FOR WYZ101-107-115-118.

NE...NONE.

&&

$$

SHORT TERM...CLH
LONG TERM...SML
AVIATION...SML
FIRE WEATHER...RJM



000
FXUS65 KCYS 212245
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
345 PM MST FRI NOV 21 2014

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

QUIET WEATHER IS QUICKLY COMING TO AN END AS WE TRANSITION INTO A
VERY ACTIVE PATTERN FOR THE SHORT TERM PERIOD. HIGHLIGHTS REVOLVE
AROUND POTENTIAL FOR VERY STRONG WINDS OVER SOUTHEAST WYOMING AND
POSSIBLY WESTERN NEBRASKA...AND MOUNTAIN SNOWS. LATEST WATER VAPOR
SATELLITE LOOP SHOWS A VIGOROUS UPPER-LEVEL SHORTWAVE JUST ABOUT TO
CRASH INTO THE PACIFIC NORTHWEST THIS EVE. OBJECTIVE UPPER ANALYSIS
SHOWS A STRONG 110+ KT JET CORE OFFSHORE AT 21Z. THIS WILL BE OUR
MAJOR WEATHER MAKER OVER THE NEXT COUPLE OF DAYS AS THE SYSTEM MOVES
RAPIDLY SOUTHEAST AND STRENGTHENS. NOT EXPECTING ANYTHING MAJOR IN
THE NEAR TERM THOUGH. SHOULD BE A QUIET EVENING WITH WINDS STARTING
TO RELAX AS MIXING DWINDLES WITH THE LOSS OF AFTN HEATING. A BROAD
AREA OF SURFACE HIGH PRESSURE WILL KEEP THINGS ON THE DRY SIDE.

THINGS CHANGE QUICKLY INTO TONIGHT. THE NAM H85 CAG-CPR GRADIENT IS
PROGGED TO CLIMB ABOVE 60 METERS BY ABOUT 09Z SAT. MODELED LLVL FLOW
IS IMPRESSIVE TO SAY THE LEAST WITH AN EXTENSIVE CORE OF 60 TO 70 KT
WINDS BETWEEN 700 AND 800 MILLIBARS OVER A GOOD CHUNK OF OUR WYOMING
ZONES BY SUNRISE. WITH EXCELLENT SUBSIDENCE OVER THE TRADITIONAL GAP
AREAS AND GOOD 6-HR PRESSURE FALLS ON THE ORDER OF 5-10 MB PER THE
GFS...CONFIDENCE IS HIGH IN A WIDESPREAD AND POTENTIALLY SIGNIFICANT
WIND EVENT. WENT AHEAD AND UPGRADED TO A HIGH WIND WARNING WITH ALL
ZONES STARTING AT 09Z. ARL AND BRX SHOULD HIT FIRST...WITH THE WIND
CORE ALOFT SPREADING INTO THE SOUTHERN LARAMIE RANGE/FOOTHILLS AT OR
AROUND SUNRISE. ADDED THE NORTHERN LARAMIE RANGE TO THE WARNING AS
WELL AS BOTH THE GFS AND NAM SHOW 65 KT WINDS AT H75 TO THE SOUTH OF
DEER CREEK IN WESTERN CONVERSE COUNTY. THIS MAY BE QUITE THE EVENT
WITH MULTIPLE GUSTS OVER 70 MPH. ANOTHER EVENTUAL CONCERN IS THE
POTENTIAL FOR LIGHT SNOW WEST OF THE LARAMIE RANGE LATER IN THE
AFTERNOON AND EVENING. WITH STRONG WINDS WILL COME THE POTENTIAL FOR
SIGNIFICANTLY REDUCED VISIBILITIES IN BLOWING SNOW EVEN THOUGH LOWER
ELEVATIONS SHOULD NOT SEE MUCH FOR ACCUMULATIONS. MADE IT A POINT TO
MENTION THIS IN THE NPW PRODUCT.

SOMEWHAT CONCERNED THAT SOME OF THE ADJACENT VALLEYS AND HIGH PLAINS
MAY GET IN ON SOME OF THE WINDY FUN TOMORROW AS WELL. THERE ARE SOME
KEY DIFFERENCES IN THE GFS AND NAM WHICH WILL HAVE A ROLE IN WHETHER
OR NOT WE SEE WARNING CRITERIA WINDS AT AREAS SUCH AS CHEYENNE AND
THE LARAMIE VALLEY. FORECAST SOUNDINGS FROM BOTH MODELS SHOW A BELT
OF VERY STRONG FLOW NOT FAR OFF THE SURFACE. THE DIFFERENCES ARE IN
THE MIXING. MAIN LIMITING FACTOR WILL BE CLOUD COVER...BUT BOTH THE
LOW AND MIDLVL RH FIELDS DO NOT SUGGEST ANYTHING THICK ENOUGH. COULD
EVENTUALLY SEE AN ABUNDANCE OF LENTICULARS EAST OF THE MOUNTAINS AS
MOUNTAIN WAVE ACTIVITY BECOMES INTENSE IN THE AFTN. IF THIS DOES NOT
IMPACT SURFACE HEATING...GFS SOUNDINGS SUGGEST 50-60 KTS AT THE TOP
OF THE MIXED LAYER AT LARAMIE AND CHEYENNE. THE NAM IS CONSIDERABLY
LESS...HOWEVER IT DOES SHOW SUBSIDENCE IN ITS OMEGA FIELDS SPREADING
SLOWLY ONTO THE PLAINS BETWEEN 18-00Z. DECIDED TO ISSUE A HIGH WIND
WATCH FOR LOWER ELEVATIONS IMMEDIATELY ADJACENT TO THE LARAMIE RANGE
AND FOOTHILLS. EVEN IF AFTERNOON MIXING IS NOT THE CULPRIT...MODELS
ARE IN GOOD AGREEMENT WITH A TRANSITION TO A BORA WIND EVENT ON SAT
NIGHT THROUGH EARLY SUN AS A COLD FRONT SWEEPS ACROSS THE CWA. COULD
SEE WIND GUSTS RAMP UP AGAIN FOR A FEW HOURS AROUND MIDNIGHT...WITH
A FEW GUSTS TO 60 MPH POSSIBLE OVERNIGHT.

SUNDAY WILL BE VERY WINDY OVER THE PLAINS OF SOUTHEAST WYOMING AND
THE WESTERN PANHANDLE. THE CWA WILL BE IN THE POST FRONTAL AIR MASS
AND THE MODELS SHOW A RIBBON OF 60 TO 70 KTS FROM NEAR LSK SOUTHEAST
TOWARD SNY AT 00Z MON. WILL LIKELY NEED MORE WIND HEADLINES FOR THIS
TIME FRAME...BUT WILL GET THROUGH THE SATURDAY EVENT FIRST. NOW THAT
THE WIND DISCUSSION IS OUT THE WAY...ONTO THE SNOW POTENTIAL. DIDNT
MAKE ANY CHANGES TO THE WINTER STORM WATCH FOR THE MOUNTAINS...BUT
IT STILL LOOKS GOOD. FIREHOSE OF AN UPPER JET WITH 150+ KT H25 CORE
IS PROGGED TO REMAIN ANCHORED OVER THE WESTERN US FOR SEVERAL DAYS
WITH OUR MOUNTAINS REMAINING IN THE FAVORED LEFT EXIT REGION. THIS
COMBINED WITH FAVORABLE OROGRAPHICS IN WEST-NORTHWEST FLOW AND AND
SEVERAL REINFORCING SHOTS OF 700-300 MILLIBAR MOISTURE EMBEDDED IN
THE ACTIVE FLOW ALOFT WILL SUPPORT PERIODS OF HEAVY SNOW. SHOULD SEE
ONE OR TWO FEET THROUGH MON WITH ADDITIONAL SNOW POSSIBLE IN THE
DAYS FOLLOWING. SHOULD BE PRIMARILY A MOUNTAIN EVENT WITH AREAS EAST
OF THE LARAMIE RANGE STAYING DRY IN DOWNSLOPING LLVL FLOW. MAY SEE A
FEW RAIN OR SNOW SHOWERS OVER THE NORTHERN PANHANDLE ON SUN AFTN AS
PVA OVERSPREADS THE AREA.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM MST FRI NOV 21 2014

BASED ON GFS/ECMWF MODEL SOLUTIONS...SHOULD SEE A BREAK IN SNOW
ACCUMULATIONS OVER SOUTHEAST WYOMING MOUNTAINS SUNDAY EVENING WITH
A SHORTWAVE RIDGE IN PLACE. THEN THE NEXT SHOT OF SNOW LIKELY TO
DEVELOP AFTER MIDNIGHT SUNDAY NIGHT. COULD SEE SOME LIGHT SNOW
INTO LOWER ELEVATIONS BUT MOST SNOW ACCUMULATIONS WILL GENERALLY
BE IN THE MOUNTAINS. VERY LITTLE CHANCE FOR ANY ACCUMULATIONS
EAST OF THE LARAMIE RANGE SUNDAY NIGHT THROUGH MONDAY. WINDS WILL
SUBSIDE ACROSS MOST OF THE AREA SUNDAY NIGHT BUT ANOTHER PUSH OF
STRONGER WINDS POSSIBLE MONDAY NIGHT AS ANOTHER STRONG UPPER LEVEL
JET MOVES OVER THE AREA. MAIN CONCERN FOR HIGH WINDS WILL BE OVER
THE FAVORED WIND PRONE LOCATIONS IN SOUTHEAST WYOMING SUCH AS
ARLINGTON...BORDEAUX AND THE SOUTHERN LARAMIE RANGE.

THE NEXT QUICK MOVING CLIPPER SYSTEM ALONG WITH THE UPPER JET
WILL BRING A CHANCE FOR LIGHT SNOW SHOWERS THROUGH TUESDAY
AFTERNOON...INCLUDING INTO THE NEBRASKA PANHANDLE. AT THIS TIME
NOT EXPECTING MUCH IN THE WAY OF SNOW ACCUMULATIONS...IF ANY. MAINLY
LOOKING FOR LIGHT SNOW SHOWERS AND FLURRIES.

UNCERTAINTLY REMAINS FOR LATER PORTIONS OF THE WEEK AND HOLIDAY
WEEKEND GIVEN THE GFS AND ECMFW WERE COMPLETELY DIFFERENT IN
THEIR SOLUTIONS YESTERDAY. HOWEVER...BOTH MODLES TRENDED TOWARD
EACH OTHER TODAY AND HAVE RATHER SIMILAR SOLUTIONS. WOULD LIKE TO
SEE RUN OR TWO OF CONSISTENCY BUT BASED ON LATEST SOLUTIONS IT
WOULD WARM BOTH THURSDAY AND FRIDAY WITH A FLATTENING RIDGE OVER
THE NORTHERN ROCKIES PRODUCING DOWNSLOPE WARMING. INTO THE
WEEKEND THE MODLES SUGGEST A FAST MOVING BUT RELATIVELY WEAK WAVE
MOVING ACROSS THE AREA...SO NO BIG HAZARDOUS WEATHER THREAT
EXPECTED AT THIS TIME.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 234 PM MST FRI NOV 21 2014

AVIATION CONCERNS TO MAINLY FOCUS ON WINDS LATE TONIGHT AND INTO
TOMORROW AND SNOW WHICH WILL DEVELOP OVER THE MOUNTAINS TOMORROW
AFTERNOON. STRONG WINDS WITH FREQUENT GUSTS TO 50 KTS AND GREATER
WILL DEVELOP IN THE ARLINGTON AREA AND INTO THE BORDEAUX AREA
LATE TONIGHT. THESE STRONG WEST TO SOUTHWEST WINDS WILL THEN
SPREAD INTO THE SOUTHERN AND NORTHERN LARAMIE RANGES TOWARD
SUNRISE SATURDAY. GUSTY WINDS WILL ALSO SPREAD INTO LOWER
ELEVATIONS AND INTO THE PLAINS OF SOUTHEAST WYOMING SATURDAY
AFTERNOON WITH GUSTS OF 30 TO 40 KTS BEING COMMON. WINDS WILL NOT
BE AS STRONG INTO THE NEBRASKA PANHANDLE BUT STILL BREEZY TO WINDY
SATURDAY AFTERNOON.

MOUNTAINS WILL BE OBSCURED DUE TO FALLING AND BLOWING SNOW
SATURDAY AFTERNOON...ESPECIALLY INTO THE SNOWY AND SIERRA MADRE
RANGES WHERE A WINTER STORM WATCH IS CURRENTLY IN EFFECT. PERIODS
OF SNOW WILL CONTINUE INTO MONDAY ACROSS THESE MOUNTAINS.

STRONG NORTHWEST WINDS EXPECTED OVER THE NEBRASKA PANHANDLE SUNDAY
WITH STRONGER WINDS ALSO POSSIBLE INTO SOUTHEAST WYOMING.

&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WARNING FROM 2 AM SATURDAY TO 5 AM MST SUNDAY FOR
     WYZ103>106-110-116-117.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH LATE SATURDAY
     NIGHT FOR WYZ101-107-115-118.

NE...NONE.

&&

$$

SHORT TERM...CLH
LONG TERM...SML
AVIATION...SML
FIRE WEATHER...RJM




000
FXUS63 KUNR 212152
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
252 PM MST FRI NOV 21 2014

.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 251 PM MST FRI NOV 21 2014

MILD CONDITIONS WILL CONTINUE THROUGH SATURDAY AS DRY
WESTERLY PAC FLOW REMAINS IN PLACE. WEAK MID LEVEL IMPULSE IS
CURRENTLY MOVING THROUGH THE REGION...SUPPORTING A SFC TROUGH INTO
THE AREA. THIS SYSTEM WILL SUPPORT LITTLE TO NO CAA...KEEPING
THERMAL FIELDS BASICALLY UNALTERED ON IT/S BACKSIDE. ATTENTION TURNS
TOWARD A STRONG MID LEVEL TROUGH NOW ENTERING THE PAC NW. THIS
SYSTEM WILL CROSS THE NORTHERN ROCKIES AND AMPLIFY PER A STAUNCH
150+ KNOT UPPER LEVEL JET...ENTERING THE NORTHERN PLAINS LATER
SATURDAY. THIS SYSTEM WILL SUPPORT STRONG LL PRESSURE
FALLS...AND A DEEPENING SFC CYCLONE OVER THE REGION BY SAT
NIGHT. THIS SYSTEM WILL QUICKLY PROGRESS THROUGH THE REGION SAT
NIGHT...SUPPORTING FRONTOGENETICAL FORCING AND RESULTING RAIN AND
SNOW...ESP OVER NE WY AND THE NORTHERN HILLS. ANY SHOWERS WILL
LIKELY START AS RAIN OR A RAIN SNOW/MIX...WITH PRECIP TYPE
TRANSITIONING TO ALL SNOW SAT NIGHT. OVERALL...PRECIP CHANCES
REMAIN IN THE SCT-ISOLD RANGE...GIVEN LACK OF SIG FOCUS UVM. ANY
SNOW ACCUMS ARE EXPECTED TO BE AN INCH OR LESS...OUTSIDE OF THE
NORTHERN HILLS WHERE A COUPLE INCHES WILL BE POSSIBLE.

AS FOR TEMPS...PAC NW SYSTEM WILL SUPPORT RE-NEWED DOWNSTREAM
RIDGING WITH AN ASSOCIATED THERMAL RIDGE...WHICH WILL ADVECT OVER
THE REGION SAT. GIVEN CYCLOGENESIS AND INCREASED SFC PRESSURE
FALLS...WESTERLY WINDS WILL INCREASE OVER THE REGION
SAT...SUPPORTING GOOD MIXING. THIS WILL ALLOW ANOTHER WARM DAY
ACROSS THE AREA...WITH 40S AND 50S COMMON ESP...WARMEST ACROSS THE
EASTERN BLACK HILLS AND SCENTRAL SD. WINDS WILL INCREASE SAT EVE
AHEAD OF THE SFC TROUGH IN THE FAVORED DOWNSLOPE AREAS ACROSS THE
BLACK HILLS...WITH WINDS INCREASING EVERYWHERE ACROSS THE REGION
LATE SAT NIGHT...POST FRONTAL. STRONG NW WINDS WILL DEVELOP AS
STAUNCH CAA COMBINES WITH SFC PRESSURE RISES AND INCREASING BL FLOW.
HAVE INCREASED WINDS SOME SAT NIGHT.

&&

.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 251 PM MST FRI NOV 21 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. A TIGHT PRESSURE GRADIENT ON THE BACKSIDE OF LOW PRESSURE
PUSHING INTO THE UPPER MIDWEST WILL BRING VERY WINDY CONDITIONS TO
MUCH OF THE WESTERN SD PLAINS ON SUNDAY. THERE IS POTENTIAL FOR
WARNING CRITERIA WINDS SUNDAY AFTERNOON ACROSS NORTHWEST AND WEST
CENTRAL SD. WILL LET NEXT SHIFT HAVE ANOTHER LOOK AND SEE IF A WATCH
IS NEEDED. UPSLOPE ENHANCED SNOW SHOWERS WILL MAINLY AFFECT THE
NORTHERN BLACK HILLS ON SUNDAY...WITH SOME LIGHT ACCUMULATIONS
LIKELY. WINDS WILL REMAIN BREEZY ON MONDAY. ADDITIONAL WEAK
DISTURBANCES IN NORTHWEST FLOW WILL BRING CLOUDS AND CHANCES FOR
SNOW SHOWERS AT TIMES THROUGH WEDNESDAY.

THERE IS STILL UNCERTAINTY TOWARD THE LATTER PART OF NEXT WEEK...BUT
LONGER RANGE MODELS ARE IN BETTER AGREEMENT RIGHT NOW FOR THE
THANKSGIVING PERIOD...WITH A MILDER AND DRIER STRETCH OF WEATHER
LOOKING MORE LIKELY. WILL GO WITH MILDER TEMPERATURES THURSDAY AND
FRIDAY...ESPECIALLY OVER WESTERN PORTIONS OF THE CWA. IF LATEST
TRENDS PERSIST...TEMPERATURES WILL BE NEAR OR ABOVE AVERAGE IN MOST
AREAS.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING
ISSUED AT 251 PM MST FRI NOV 21 2014

VFR CONDITIONS ARE EXPECTED THROUGH EARLY SATURDAY.
BREEZY SOUTHWESTERLY WINDS WILL DEVELOP ACROSS NORTHEAST WY
OVERNIGHT.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...JC
LONG TERM...26
AVIATION...26







000
FXUS63 KUNR 212152
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
252 PM MST FRI NOV 21 2014

.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 251 PM MST FRI NOV 21 2014

MILD CONDITIONS WILL CONTINUE THROUGH SATURDAY AS DRY
WESTERLY PAC FLOW REMAINS IN PLACE. WEAK MID LEVEL IMPULSE IS
CURRENTLY MOVING THROUGH THE REGION...SUPPORTING A SFC TROUGH INTO
THE AREA. THIS SYSTEM WILL SUPPORT LITTLE TO NO CAA...KEEPING
THERMAL FIELDS BASICALLY UNALTERED ON IT/S BACKSIDE. ATTENTION TURNS
TOWARD A STRONG MID LEVEL TROUGH NOW ENTERING THE PAC NW. THIS
SYSTEM WILL CROSS THE NORTHERN ROCKIES AND AMPLIFY PER A STAUNCH
150+ KNOT UPPER LEVEL JET...ENTERING THE NORTHERN PLAINS LATER
SATURDAY. THIS SYSTEM WILL SUPPORT STRONG LL PRESSURE
FALLS...AND A DEEPENING SFC CYCLONE OVER THE REGION BY SAT
NIGHT. THIS SYSTEM WILL QUICKLY PROGRESS THROUGH THE REGION SAT
NIGHT...SUPPORTING FRONTOGENETICAL FORCING AND RESULTING RAIN AND
SNOW...ESP OVER NE WY AND THE NORTHERN HILLS. ANY SHOWERS WILL
LIKELY START AS RAIN OR A RAIN SNOW/MIX...WITH PRECIP TYPE
TRANSITIONING TO ALL SNOW SAT NIGHT. OVERALL...PRECIP CHANCES
REMAIN IN THE SCT-ISOLD RANGE...GIVEN LACK OF SIG FOCUS UVM. ANY
SNOW ACCUMS ARE EXPECTED TO BE AN INCH OR LESS...OUTSIDE OF THE
NORTHERN HILLS WHERE A COUPLE INCHES WILL BE POSSIBLE.

AS FOR TEMPS...PAC NW SYSTEM WILL SUPPORT RE-NEWED DOWNSTREAM
RIDGING WITH AN ASSOCIATED THERMAL RIDGE...WHICH WILL ADVECT OVER
THE REGION SAT. GIVEN CYCLOGENESIS AND INCREASED SFC PRESSURE
FALLS...WESTERLY WINDS WILL INCREASE OVER THE REGION
SAT...SUPPORTING GOOD MIXING. THIS WILL ALLOW ANOTHER WARM DAY
ACROSS THE AREA...WITH 40S AND 50S COMMON ESP...WARMEST ACROSS THE
EASTERN BLACK HILLS AND SCENTRAL SD. WINDS WILL INCREASE SAT EVE
AHEAD OF THE SFC TROUGH IN THE FAVORED DOWNSLOPE AREAS ACROSS THE
BLACK HILLS...WITH WINDS INCREASING EVERYWHERE ACROSS THE REGION
LATE SAT NIGHT...POST FRONTAL. STRONG NW WINDS WILL DEVELOP AS
STAUNCH CAA COMBINES WITH SFC PRESSURE RISES AND INCREASING BL FLOW.
HAVE INCREASED WINDS SOME SAT NIGHT.

&&

.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 251 PM MST FRI NOV 21 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. A TIGHT PRESSURE GRADIENT ON THE BACKSIDE OF LOW PRESSURE
PUSHING INTO THE UPPER MIDWEST WILL BRING VERY WINDY CONDITIONS TO
MUCH OF THE WESTERN SD PLAINS ON SUNDAY. THERE IS POTENTIAL FOR
WARNING CRITERIA WINDS SUNDAY AFTERNOON ACROSS NORTHWEST AND WEST
CENTRAL SD. WILL LET NEXT SHIFT HAVE ANOTHER LOOK AND SEE IF A WATCH
IS NEEDED. UPSLOPE ENHANCED SNOW SHOWERS WILL MAINLY AFFECT THE
NORTHERN BLACK HILLS ON SUNDAY...WITH SOME LIGHT ACCUMULATIONS
LIKELY. WINDS WILL REMAIN BREEZY ON MONDAY. ADDITIONAL WEAK
DISTURBANCES IN NORTHWEST FLOW WILL BRING CLOUDS AND CHANCES FOR
SNOW SHOWERS AT TIMES THROUGH WEDNESDAY.

THERE IS STILL UNCERTAINTY TOWARD THE LATTER PART OF NEXT WEEK...BUT
LONGER RANGE MODELS ARE IN BETTER AGREEMENT RIGHT NOW FOR THE
THANKSGIVING PERIOD...WITH A MILDER AND DRIER STRETCH OF WEATHER
LOOKING MORE LIKELY. WILL GO WITH MILDER TEMPERATURES THURSDAY AND
FRIDAY...ESPECIALLY OVER WESTERN PORTIONS OF THE CWA. IF LATEST
TRENDS PERSIST...TEMPERATURES WILL BE NEAR OR ABOVE AVERAGE IN MOST
AREAS.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING
ISSUED AT 251 PM MST FRI NOV 21 2014

VFR CONDITIONS ARE EXPECTED THROUGH EARLY SATURDAY.
BREEZY SOUTHWESTERLY WINDS WILL DEVELOP ACROSS NORTHEAST WY
OVERNIGHT.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...JC
LONG TERM...26
AVIATION...26






000
FXUS63 KUNR 212152
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
252 PM MST FRI NOV 21 2014

.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 251 PM MST FRI NOV 21 2014

MILD CONDITIONS WILL CONTINUE THROUGH SATURDAY AS DRY
WESTERLY PAC FLOW REMAINS IN PLACE. WEAK MID LEVEL IMPULSE IS
CURRENTLY MOVING THROUGH THE REGION...SUPPORTING A SFC TROUGH INTO
THE AREA. THIS SYSTEM WILL SUPPORT LITTLE TO NO CAA...KEEPING
THERMAL FIELDS BASICALLY UNALTERED ON IT/S BACKSIDE. ATTENTION TURNS
TOWARD A STRONG MID LEVEL TROUGH NOW ENTERING THE PAC NW. THIS
SYSTEM WILL CROSS THE NORTHERN ROCKIES AND AMPLIFY PER A STAUNCH
150+ KNOT UPPER LEVEL JET...ENTERING THE NORTHERN PLAINS LATER
SATURDAY. THIS SYSTEM WILL SUPPORT STRONG LL PRESSURE
FALLS...AND A DEEPENING SFC CYCLONE OVER THE REGION BY SAT
NIGHT. THIS SYSTEM WILL QUICKLY PROGRESS THROUGH THE REGION SAT
NIGHT...SUPPORTING FRONTOGENETICAL FORCING AND RESULTING RAIN AND
SNOW...ESP OVER NE WY AND THE NORTHERN HILLS. ANY SHOWERS WILL
LIKELY START AS RAIN OR A RAIN SNOW/MIX...WITH PRECIP TYPE
TRANSITIONING TO ALL SNOW SAT NIGHT. OVERALL...PRECIP CHANCES
REMAIN IN THE SCT-ISOLD RANGE...GIVEN LACK OF SIG FOCUS UVM. ANY
SNOW ACCUMS ARE EXPECTED TO BE AN INCH OR LESS...OUTSIDE OF THE
NORTHERN HILLS WHERE A COUPLE INCHES WILL BE POSSIBLE.

AS FOR TEMPS...PAC NW SYSTEM WILL SUPPORT RE-NEWED DOWNSTREAM
RIDGING WITH AN ASSOCIATED THERMAL RIDGE...WHICH WILL ADVECT OVER
THE REGION SAT. GIVEN CYCLOGENESIS AND INCREASED SFC PRESSURE
FALLS...WESTERLY WINDS WILL INCREASE OVER THE REGION
SAT...SUPPORTING GOOD MIXING. THIS WILL ALLOW ANOTHER WARM DAY
ACROSS THE AREA...WITH 40S AND 50S COMMON ESP...WARMEST ACROSS THE
EASTERN BLACK HILLS AND SCENTRAL SD. WINDS WILL INCREASE SAT EVE
AHEAD OF THE SFC TROUGH IN THE FAVORED DOWNSLOPE AREAS ACROSS THE
BLACK HILLS...WITH WINDS INCREASING EVERYWHERE ACROSS THE REGION
LATE SAT NIGHT...POST FRONTAL. STRONG NW WINDS WILL DEVELOP AS
STAUNCH CAA COMBINES WITH SFC PRESSURE RISES AND INCREASING BL FLOW.
HAVE INCREASED WINDS SOME SAT NIGHT.

&&

.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 251 PM MST FRI NOV 21 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. A TIGHT PRESSURE GRADIENT ON THE BACKSIDE OF LOW PRESSURE
PUSHING INTO THE UPPER MIDWEST WILL BRING VERY WINDY CONDITIONS TO
MUCH OF THE WESTERN SD PLAINS ON SUNDAY. THERE IS POTENTIAL FOR
WARNING CRITERIA WINDS SUNDAY AFTERNOON ACROSS NORTHWEST AND WEST
CENTRAL SD. WILL LET NEXT SHIFT HAVE ANOTHER LOOK AND SEE IF A WATCH
IS NEEDED. UPSLOPE ENHANCED SNOW SHOWERS WILL MAINLY AFFECT THE
NORTHERN BLACK HILLS ON SUNDAY...WITH SOME LIGHT ACCUMULATIONS
LIKELY. WINDS WILL REMAIN BREEZY ON MONDAY. ADDITIONAL WEAK
DISTURBANCES IN NORTHWEST FLOW WILL BRING CLOUDS AND CHANCES FOR
SNOW SHOWERS AT TIMES THROUGH WEDNESDAY.

THERE IS STILL UNCERTAINTY TOWARD THE LATTER PART OF NEXT WEEK...BUT
LONGER RANGE MODELS ARE IN BETTER AGREEMENT RIGHT NOW FOR THE
THANKSGIVING PERIOD...WITH A MILDER AND DRIER STRETCH OF WEATHER
LOOKING MORE LIKELY. WILL GO WITH MILDER TEMPERATURES THURSDAY AND
FRIDAY...ESPECIALLY OVER WESTERN PORTIONS OF THE CWA. IF LATEST
TRENDS PERSIST...TEMPERATURES WILL BE NEAR OR ABOVE AVERAGE IN MOST
AREAS.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING
ISSUED AT 251 PM MST FRI NOV 21 2014

VFR CONDITIONS ARE EXPECTED THROUGH EARLY SATURDAY.
BREEZY SOUTHWESTERLY WINDS WILL DEVELOP ACROSS NORTHEAST WY
OVERNIGHT.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...JC
LONG TERM...26
AVIATION...26







000
FXUS65 KRIW 212142
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
242 PM MST FRI NOV 21 2014

.SHORT TERM...TONIGHT THROUGH SATURDAY

AN INTERESTING PERIOD. RELATIVELY BENIGN CONDITIONS EXPECTED
DURING THE EARLY EVENING HOURS TONIGHT...WITH A SIGNIFICANT WINTER
SYSTEM EXPECTED TO IMPACT THE AREA DURING THE OVERNIGHT HOURS.
SNOWFALL WILL BEGIN BEFORE MIDNIGHT...WITH ACTIVITY AND COVERAGE
INCREASING THROUGH THE OVERNIGHT HOURS. SNOWFALL RATES WILL
INCREASE DURING THE MORNING HOURS...ESPECIALLY BETWEEN 0500 AND
1100 SATURDAY. SNOWFALL ASSOCIATED WITH THIS SYSTEM WILL CONTINUE
IMPACT THE AREA THROUGH SATURDAY...WITH ACTIVITY SPREADING TO
INCLUDE PORTIONS OF SOUTHERN WYOMING DURING SATURDAY AFTERNOON.

SNOWFALL ACCUMULATIONS WILL BE SIGNIFICANT ACROSS THE WESTERN
MOUNTAINS AND VALLEYS...WITH SOME LESSER AMOUNTS EXPECTED ACROSS
SOUTHERN WYOMING. STORM STORM WILL CONTINUE INTO SATURDAY
NIGHT...WITH FURTHER DETAILS ON TOTAL ACCUMULATIONS COVERED IN THE
LONG TERM SECTION.

.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
THE SHORTWAVE EJECTED BY THE LOW SPINNING AROUND IN THE ALEUTIANS
WILL BE CROSSING OVER OUR AREA AROUND 06Z SATURDAY NIGHT. AFTER THE
FROPA...THE SNOWFALL INTENSITY WILL BEGIN TO DIMINISH IN THE WEST.
HOWEVER...MANY AREAS OF SWEETWATER COUNTY SHOULD SEE 2 TO 3 INCHES
OF SNOWFALL SATURDAY NIGHT FROM THE COMBINATION OF THE ASCT STRONG
PACIFIC COLD FRONT AND Q VECTOR FORCING. THE WIND RIVER BASIN ALMOST
ALWAYS MANAGES TO RECEIVE AT LEAST JUST UNDER AN INCH OF SNOWFALL
WHENEVER CENTRAL WYOMING RECEIVES THE BRUNT OF THE 700MB COLD PUNCH
FROM A CLASSIC CATAFRONT LIKE THIS ONE AS WILL BE THE CASE SATURDAY
NIGHT...SO INCREASED POPS THERE AS WELL AS ADDED CORRESPONDING SNOW
ACCUMULATIONS THERE. JOHNSON COUNTY IS ANOTHER AREA TO WATCH FOR
MORE PRECIP SINCE THAT AREA WILL BE CLOSER TO THE 700MB LOW TRACKING
EAST SOUTHEAST ACROSS NORTH DAKOTA BUT THE PRECIP THERE WILL START
AS RAIN SO NOT EXPECTING TOO MUCH IN THE WAY OF ACCUMULATING SNOW
THERE. SNOW TOTALS OF 3 TO 5 INCHES WILL BE COMMON IN THE BIG HORN
MTNS.

AS FAR AS SNOW TOTALS GO IN THE FAR WEST...BY 12Z SUNDAY MORNING WE
WILL BE LOOKING AT 12 TO 20 INCHES IN THE TETONS...GROS VENTRE
RANGE...SALT AND WYOMING RANGES AND ALONG AND WEST OF THE DIVIDE IN
THE WIND RIVER MTNS ALONG WITH LOCAL AMOUNTS OF UP TO 26 INCHES. THE
JACKSON VALLEY CAN EXPECT 8 TO 12 INCHES WITH THE HIGHEST AMOUNTS
EXPECTED IN THE NORTH. THE STAR VALLEY WILL SEE 6 TO 8 INCHES.
SOUTHERN LINCOLN COUNTY WILL SEE 2 TO 4 INCHES AROUND OPAL AND 4 TO
8 INCHES AROUND COKEVILLE. YELLOWSTONE PARK WILL HAVE SNOW TOTALS
RANGING FROM 16 INCHES IN THE SOUTHWEST TO 3 TO 8 INCHES IN THE
NORTH INCLUDING MAMMOTH. THE ABSAROKAS WILL SEE UP TO A FOOT IN THE
WEST TO MAINLY 3 TO 10 INCHES IN THE EAST. AREAS JUST WEST OF DUBOIS
WILL SEE 4 TO 8 INCHES WITH 1 TO 3 INCHES JUST TO THE EAST. THE
UPPER GREEN RIVER FOOTHILLS WILL SEE AROUND 9 INCHES AT BONDURANT TO
5 INCHES IN PINEDALE. THE UPPER GREEN RIVER BASIN WILL SEE 3 TO 6
INCHES.

POST FRONTAL 7 TO 8MB...3 HOURLY SFC PRESSURE RISES WILL KEEP
POST FRONTAL NW WINDS UP THROUGH MID DAY SATURDAY IN THE 30 TO 40
MPH RANGE WITH GUSTS TO 50 MPH IN THE WIND RIVER BASIN AND NORTHERN
JOHNSON COUNTY. HIGH TEMPERATURES SUNDAY SHOULD BE 10 TO 15 DEGREES
COLDER SUNDAY THAN ON SATURDAY MOST AREAS. OCCASIONAL SNOWFALL WILL
CONTINUE THROUGH SUNDAY AND INTO MONDAY IN THE FAR WEST AS A SERIES
OF VORT LOBES PARADES WITHIN THE NORTHWEST FLOW WITH ONE DISTINCT
SHORTWAVE COMING THROUGH MONDAY. ON TUESDAY THE JET STREAM WILL PASS
OVERHEAD AS IT SLIDES OFF TO THE NORTHEAST OF US WHICH WILL PULL IN
MORE MOISTURE FROM THE NORTHWEST CONTINUING THE LIGHT TO
OCCASIONALLY MODERATE SNOW IN THE NORTHWEST MTNS. EXCEPT FOR SOME
CONTINUING LIGHT SNOW IN THE BIG HORN MTNS...AREAS EAST OF THE
DIVIDE WILL DRY OUT AFTER SATURDAY NIGHT. FOR THE REST OF THE
WEEK... TUESDAY NIGHT THROUGH THU...THE GFS AND THE EURO HAVE COME
MORE IN LINE WITH A HIGH PRESSURE RIDGE BUILDING IN FROM THE WEST
WITH A GRADUAL WARMING TREND. HOWEVER...WITH THE RIDGE AXIS STILL TO
THE WEST AND CONTINUING NW FLOW...WILL KEEP LOW POPS IN THE NORTHERN
AND CENTRAL MTNS FOR THIS TIME FRAME. WOULD RATHER WAIT FOR MORE RUN
TO RUN MODEL CONSISTENCY BEFORE WE WOULD BE WILLING TO TONE DOWN THE
MTN POPS ANY MORE THAN THEY ALREADY ARE...ESPECIALLY SINCE THIS IS A
SENSITIVE TIME OF THE MONTH GIVEN ALL THE HOLIDAY TRAVELERS.

&&

.AVIATION.../00Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES

VFR CONDITIONS EXPECTED ACROSS THE AREA THROUGH THE EVENING
HOURS...THOUGH PERIODS OF BREEZY WIND WILL BE FOUND AT KCPR AND
AREAS SOUTHWEST OF THE TERMINAL. THE APPROACHING WINTER SYSTEM
WILL CAUSE WIND SHEAR OVER MANY OF THE TERMINALS AFTER 08Z THIS
EVENING. LLWS HAS BEEN INCLUDED AT THE MAJORITY OF
TERMINALS...EXCEPT AT KCPR. UPPER LEVEL WIND WILL STILL BE STRONG
AT KCPR AS WELL...BUT WITH ALREADY STRONG SURFACE WIND
PRESENT...THE CHANGE BETWEEN SPEEDS AT THE LEVELS IS NOT AS
SIGNIFICANT. SNOWFALL WILL SPREAD ACROSS THE AREA THROUGH SATURDAY
AFTERNOON...WITH MOST TERMINALS SEEING AT LEAST VCSH BY 20Z. KCPR
IS THE EXCEPTION WITH SNOWFALL ANTICIPATED TO BEGIN AFTER 00Z
SUNDAY.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES

A FAIRLY MESSY AVIATION PERIOD AHEAD FOR AREAS WEST OF THE
CONTINENTAL DIVIDE. SNOWFALL ASSOCIATED WITH THE APPROACHING
WINTER SYSTEM WILL BEING TO IMPACT THE WESTERN MOUNTAINS AND
VALLEYS AFTER 03Z THIS EVENING...WITH PREVAILING -SN ANTICIPATED
AFTER 09Z AT KJAC. SNOWFALL WILL INTENSIFY AND INCREASE IN
COVERAGE THROUGH THE OVERNIGHT HOURS...WITH MOST TERMINALS SEEING
PREVAILING SNOW BY 14Z SATURDAY. ADDITIONALLY...STRONG WIND SHEAR
WILL BE PRESENT AT THE TERMINALS...ESPECIALLY AFTER 09Z THIS
EVENING. EXPECT INCREASED TURBULENCE OVER THE WESTERN AVIATION
PASSES...AND ALSO MOUNTAIN OBSCURATION WITH LOW CLOUDS AND ONGOING
SNOWFALL.

&&

.FIRE WEATHER...

A SIGNIFICANT WINTER WEATHER SYSTEM WILL BEGIN IMPACTING WESTERN
WYOMING THIS EVENING...AND SNOWFALL SPREADING TO INCLUDE MUCH OF
THE FORECAST AREA BY SATURDAY AFTERNOON. WINTER WEATHER HIGHLIGHTS
AREA IN EFFECT. ADDITIONALLY...STRONG WIND WILL DEVELOP ACROSS THE
WIND CORRIDOR BETWEEN ROCK SPRINGS AND CASPER...AND WILL ALSO
DEVELOP IN THE CODY FOOTHILLS. HIGH WIND WARNINGS ARE IN EFFECT
FOR MUCH OF THE DAY SATURDAY FOR THESE LOCATIONS. FIRE WEATHER
BEHAVIOR IS EXPECTED TO REMAIN MINIMAL UNDER THIS SYSTEM...WITH
THE BEST DISPERSION RATES OCCURRING DURING THE STORM. PLEASE SEE
THE APPROPRIATE WEATHER HIGHLIGHT PRODUCT FOR ADDITIONAL
INFORMATION REGARDING THE WINTER STORM AND HIGH WIND
WARNINGS...AND THE WINTER WEATHER ADVISORY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM 6 AM SATURDAY TO MIDNIGHT MST SATURDAY
NIGHT WYZ003-019-020-022.

WINTER WEATHER ADVISORY FROM 3 AM SATURDAY TO 6 AM MST SUNDAY
WYZ016-026-027.

WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 AM MST SUNDAY
WYZ001-002-012>015-023>025.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...LIPSON
AVIATION...BRANHAM
FIRE WEATHER...BRANHAM







000
FXUS65 KRIW 212142
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
242 PM MST FRI NOV 21 2014

.SHORT TERM...TONIGHT THROUGH SATURDAY

AN INTERESTING PERIOD. RELATIVELY BENIGN CONDITIONS EXPECTED
DURING THE EARLY EVENING HOURS TONIGHT...WITH A SIGNIFICANT WINTER
SYSTEM EXPECTED TO IMPACT THE AREA DURING THE OVERNIGHT HOURS.
SNOWFALL WILL BEGIN BEFORE MIDNIGHT...WITH ACTIVITY AND COVERAGE
INCREASING THROUGH THE OVERNIGHT HOURS. SNOWFALL RATES WILL
INCREASE DURING THE MORNING HOURS...ESPECIALLY BETWEEN 0500 AND
1100 SATURDAY. SNOWFALL ASSOCIATED WITH THIS SYSTEM WILL CONTINUE
IMPACT THE AREA THROUGH SATURDAY...WITH ACTIVITY SPREADING TO
INCLUDE PORTIONS OF SOUTHERN WYOMING DURING SATURDAY AFTERNOON.

SNOWFALL ACCUMULATIONS WILL BE SIGNIFICANT ACROSS THE WESTERN
MOUNTAINS AND VALLEYS...WITH SOME LESSER AMOUNTS EXPECTED ACROSS
SOUTHERN WYOMING. STORM STORM WILL CONTINUE INTO SATURDAY
NIGHT...WITH FURTHER DETAILS ON TOTAL ACCUMULATIONS COVERED IN THE
LONG TERM SECTION.

.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
THE SHORTWAVE EJECTED BY THE LOW SPINNING AROUND IN THE ALEUTIANS
WILL BE CROSSING OVER OUR AREA AROUND 06Z SATURDAY NIGHT. AFTER THE
FROPA...THE SNOWFALL INTENSITY WILL BEGIN TO DIMINISH IN THE WEST.
HOWEVER...MANY AREAS OF SWEETWATER COUNTY SHOULD SEE 2 TO 3 INCHES
OF SNOWFALL SATURDAY NIGHT FROM THE COMBINATION OF THE ASCT STRONG
PACIFIC COLD FRONT AND Q VECTOR FORCING. THE WIND RIVER BASIN ALMOST
ALWAYS MANAGES TO RECEIVE AT LEAST JUST UNDER AN INCH OF SNOWFALL
WHENEVER CENTRAL WYOMING RECEIVES THE BRUNT OF THE 700MB COLD PUNCH
FROM A CLASSIC CATAFRONT LIKE THIS ONE AS WILL BE THE CASE SATURDAY
NIGHT...SO INCREASED POPS THERE AS WELL AS ADDED CORRESPONDING SNOW
ACCUMULATIONS THERE. JOHNSON COUNTY IS ANOTHER AREA TO WATCH FOR
MORE PRECIP SINCE THAT AREA WILL BE CLOSER TO THE 700MB LOW TRACKING
EAST SOUTHEAST ACROSS NORTH DAKOTA BUT THE PRECIP THERE WILL START
AS RAIN SO NOT EXPECTING TOO MUCH IN THE WAY OF ACCUMULATING SNOW
THERE. SNOW TOTALS OF 3 TO 5 INCHES WILL BE COMMON IN THE BIG HORN
MTNS.

AS FAR AS SNOW TOTALS GO IN THE FAR WEST...BY 12Z SUNDAY MORNING WE
WILL BE LOOKING AT 12 TO 20 INCHES IN THE TETONS...GROS VENTRE
RANGE...SALT AND WYOMING RANGES AND ALONG AND WEST OF THE DIVIDE IN
THE WIND RIVER MTNS ALONG WITH LOCAL AMOUNTS OF UP TO 26 INCHES. THE
JACKSON VALLEY CAN EXPECT 8 TO 12 INCHES WITH THE HIGHEST AMOUNTS
EXPECTED IN THE NORTH. THE STAR VALLEY WILL SEE 6 TO 8 INCHES.
SOUTHERN LINCOLN COUNTY WILL SEE 2 TO 4 INCHES AROUND OPAL AND 4 TO
8 INCHES AROUND COKEVILLE. YELLOWSTONE PARK WILL HAVE SNOW TOTALS
RANGING FROM 16 INCHES IN THE SOUTHWEST TO 3 TO 8 INCHES IN THE
NORTH INCLUDING MAMMOTH. THE ABSAROKAS WILL SEE UP TO A FOOT IN THE
WEST TO MAINLY 3 TO 10 INCHES IN THE EAST. AREAS JUST WEST OF DUBOIS
WILL SEE 4 TO 8 INCHES WITH 1 TO 3 INCHES JUST TO THE EAST. THE
UPPER GREEN RIVER FOOTHILLS WILL SEE AROUND 9 INCHES AT BONDURANT TO
5 INCHES IN PINEDALE. THE UPPER GREEN RIVER BASIN WILL SEE 3 TO 6
INCHES.

POST FRONTAL 7 TO 8MB...3 HOURLY SFC PRESSURE RISES WILL KEEP
POST FRONTAL NW WINDS UP THROUGH MID DAY SATURDAY IN THE 30 TO 40
MPH RANGE WITH GUSTS TO 50 MPH IN THE WIND RIVER BASIN AND NORTHERN
JOHNSON COUNTY. HIGH TEMPERATURES SUNDAY SHOULD BE 10 TO 15 DEGREES
COLDER SUNDAY THAN ON SATURDAY MOST AREAS. OCCASIONAL SNOWFALL WILL
CONTINUE THROUGH SUNDAY AND INTO MONDAY IN THE FAR WEST AS A SERIES
OF VORT LOBES PARADES WITHIN THE NORTHWEST FLOW WITH ONE DISTINCT
SHORTWAVE COMING THROUGH MONDAY. ON TUESDAY THE JET STREAM WILL PASS
OVERHEAD AS IT SLIDES OFF TO THE NORTHEAST OF US WHICH WILL PULL IN
MORE MOISTURE FROM THE NORTHWEST CONTINUING THE LIGHT TO
OCCASIONALLY MODERATE SNOW IN THE NORTHWEST MTNS. EXCEPT FOR SOME
CONTINUING LIGHT SNOW IN THE BIG HORN MTNS...AREAS EAST OF THE
DIVIDE WILL DRY OUT AFTER SATURDAY NIGHT. FOR THE REST OF THE
WEEK... TUESDAY NIGHT THROUGH THU...THE GFS AND THE EURO HAVE COME
MORE IN LINE WITH A HIGH PRESSURE RIDGE BUILDING IN FROM THE WEST
WITH A GRADUAL WARMING TREND. HOWEVER...WITH THE RIDGE AXIS STILL TO
THE WEST AND CONTINUING NW FLOW...WILL KEEP LOW POPS IN THE NORTHERN
AND CENTRAL MTNS FOR THIS TIME FRAME. WOULD RATHER WAIT FOR MORE RUN
TO RUN MODEL CONSISTENCY BEFORE WE WOULD BE WILLING TO TONE DOWN THE
MTN POPS ANY MORE THAN THEY ALREADY ARE...ESPECIALLY SINCE THIS IS A
SENSITIVE TIME OF THE MONTH GIVEN ALL THE HOLIDAY TRAVELERS.

&&

.AVIATION.../00Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES

VFR CONDITIONS EXPECTED ACROSS THE AREA THROUGH THE EVENING
HOURS...THOUGH PERIODS OF BREEZY WIND WILL BE FOUND AT KCPR AND
AREAS SOUTHWEST OF THE TERMINAL. THE APPROACHING WINTER SYSTEM
WILL CAUSE WIND SHEAR OVER MANY OF THE TERMINALS AFTER 08Z THIS
EVENING. LLWS HAS BEEN INCLUDED AT THE MAJORITY OF
TERMINALS...EXCEPT AT KCPR. UPPER LEVEL WIND WILL STILL BE STRONG
AT KCPR AS WELL...BUT WITH ALREADY STRONG SURFACE WIND
PRESENT...THE CHANGE BETWEEN SPEEDS AT THE LEVELS IS NOT AS
SIGNIFICANT. SNOWFALL WILL SPREAD ACROSS THE AREA THROUGH SATURDAY
AFTERNOON...WITH MOST TERMINALS SEEING AT LEAST VCSH BY 20Z. KCPR
IS THE EXCEPTION WITH SNOWFALL ANTICIPATED TO BEGIN AFTER 00Z
SUNDAY.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES

A FAIRLY MESSY AVIATION PERIOD AHEAD FOR AREAS WEST OF THE
CONTINENTAL DIVIDE. SNOWFALL ASSOCIATED WITH THE APPROACHING
WINTER SYSTEM WILL BEING TO IMPACT THE WESTERN MOUNTAINS AND
VALLEYS AFTER 03Z THIS EVENING...WITH PREVAILING -SN ANTICIPATED
AFTER 09Z AT KJAC. SNOWFALL WILL INTENSIFY AND INCREASE IN
COVERAGE THROUGH THE OVERNIGHT HOURS...WITH MOST TERMINALS SEEING
PREVAILING SNOW BY 14Z SATURDAY. ADDITIONALLY...STRONG WIND SHEAR
WILL BE PRESENT AT THE TERMINALS...ESPECIALLY AFTER 09Z THIS
EVENING. EXPECT INCREASED TURBULENCE OVER THE WESTERN AVIATION
PASSES...AND ALSO MOUNTAIN OBSCURATION WITH LOW CLOUDS AND ONGOING
SNOWFALL.

&&

.FIRE WEATHER...

A SIGNIFICANT WINTER WEATHER SYSTEM WILL BEGIN IMPACTING WESTERN
WYOMING THIS EVENING...AND SNOWFALL SPREADING TO INCLUDE MUCH OF
THE FORECAST AREA BY SATURDAY AFTERNOON. WINTER WEATHER HIGHLIGHTS
AREA IN EFFECT. ADDITIONALLY...STRONG WIND WILL DEVELOP ACROSS THE
WIND CORRIDOR BETWEEN ROCK SPRINGS AND CASPER...AND WILL ALSO
DEVELOP IN THE CODY FOOTHILLS. HIGH WIND WARNINGS ARE IN EFFECT
FOR MUCH OF THE DAY SATURDAY FOR THESE LOCATIONS. FIRE WEATHER
BEHAVIOR IS EXPECTED TO REMAIN MINIMAL UNDER THIS SYSTEM...WITH
THE BEST DISPERSION RATES OCCURRING DURING THE STORM. PLEASE SEE
THE APPROPRIATE WEATHER HIGHLIGHT PRODUCT FOR ADDITIONAL
INFORMATION REGARDING THE WINTER STORM AND HIGH WIND
WARNINGS...AND THE WINTER WEATHER ADVISORY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM 6 AM SATURDAY TO MIDNIGHT MST SATURDAY
NIGHT WYZ003-019-020-022.

WINTER WEATHER ADVISORY FROM 3 AM SATURDAY TO 6 AM MST SUNDAY
WYZ016-026-027.

WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 AM MST SUNDAY
WYZ001-002-012>015-023>025.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...LIPSON
AVIATION...BRANHAM
FIRE WEATHER...BRANHAM








000
FXUS65 KRIW 212142
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
242 PM MST FRI NOV 21 2014

.SHORT TERM...TONIGHT THROUGH SATURDAY

AN INTERESTING PERIOD. RELATIVELY BENIGN CONDITIONS EXPECTED
DURING THE EARLY EVENING HOURS TONIGHT...WITH A SIGNIFICANT WINTER
SYSTEM EXPECTED TO IMPACT THE AREA DURING THE OVERNIGHT HOURS.
SNOWFALL WILL BEGIN BEFORE MIDNIGHT...WITH ACTIVITY AND COVERAGE
INCREASING THROUGH THE OVERNIGHT HOURS. SNOWFALL RATES WILL
INCREASE DURING THE MORNING HOURS...ESPECIALLY BETWEEN 0500 AND
1100 SATURDAY. SNOWFALL ASSOCIATED WITH THIS SYSTEM WILL CONTINUE
IMPACT THE AREA THROUGH SATURDAY...WITH ACTIVITY SPREADING TO
INCLUDE PORTIONS OF SOUTHERN WYOMING DURING SATURDAY AFTERNOON.

SNOWFALL ACCUMULATIONS WILL BE SIGNIFICANT ACROSS THE WESTERN
MOUNTAINS AND VALLEYS...WITH SOME LESSER AMOUNTS EXPECTED ACROSS
SOUTHERN WYOMING. STORM STORM WILL CONTINUE INTO SATURDAY
NIGHT...WITH FURTHER DETAILS ON TOTAL ACCUMULATIONS COVERED IN THE
LONG TERM SECTION.

.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
THE SHORTWAVE EJECTED BY THE LOW SPINNING AROUND IN THE ALEUTIANS
WILL BE CROSSING OVER OUR AREA AROUND 06Z SATURDAY NIGHT. AFTER THE
FROPA...THE SNOWFALL INTENSITY WILL BEGIN TO DIMINISH IN THE WEST.
HOWEVER...MANY AREAS OF SWEETWATER COUNTY SHOULD SEE 2 TO 3 INCHES
OF SNOWFALL SATURDAY NIGHT FROM THE COMBINATION OF THE ASCT STRONG
PACIFIC COLD FRONT AND Q VECTOR FORCING. THE WIND RIVER BASIN ALMOST
ALWAYS MANAGES TO RECEIVE AT LEAST JUST UNDER AN INCH OF SNOWFALL
WHENEVER CENTRAL WYOMING RECEIVES THE BRUNT OF THE 700MB COLD PUNCH
FROM A CLASSIC CATAFRONT LIKE THIS ONE AS WILL BE THE CASE SATURDAY
NIGHT...SO INCREASED POPS THERE AS WELL AS ADDED CORRESPONDING SNOW
ACCUMULATIONS THERE. JOHNSON COUNTY IS ANOTHER AREA TO WATCH FOR
MORE PRECIP SINCE THAT AREA WILL BE CLOSER TO THE 700MB LOW TRACKING
EAST SOUTHEAST ACROSS NORTH DAKOTA BUT THE PRECIP THERE WILL START
AS RAIN SO NOT EXPECTING TOO MUCH IN THE WAY OF ACCUMULATING SNOW
THERE. SNOW TOTALS OF 3 TO 5 INCHES WILL BE COMMON IN THE BIG HORN
MTNS.

AS FAR AS SNOW TOTALS GO IN THE FAR WEST...BY 12Z SUNDAY MORNING WE
WILL BE LOOKING AT 12 TO 20 INCHES IN THE TETONS...GROS VENTRE
RANGE...SALT AND WYOMING RANGES AND ALONG AND WEST OF THE DIVIDE IN
THE WIND RIVER MTNS ALONG WITH LOCAL AMOUNTS OF UP TO 26 INCHES. THE
JACKSON VALLEY CAN EXPECT 8 TO 12 INCHES WITH THE HIGHEST AMOUNTS
EXPECTED IN THE NORTH. THE STAR VALLEY WILL SEE 6 TO 8 INCHES.
SOUTHERN LINCOLN COUNTY WILL SEE 2 TO 4 INCHES AROUND OPAL AND 4 TO
8 INCHES AROUND COKEVILLE. YELLOWSTONE PARK WILL HAVE SNOW TOTALS
RANGING FROM 16 INCHES IN THE SOUTHWEST TO 3 TO 8 INCHES IN THE
NORTH INCLUDING MAMMOTH. THE ABSAROKAS WILL SEE UP TO A FOOT IN THE
WEST TO MAINLY 3 TO 10 INCHES IN THE EAST. AREAS JUST WEST OF DUBOIS
WILL SEE 4 TO 8 INCHES WITH 1 TO 3 INCHES JUST TO THE EAST. THE
UPPER GREEN RIVER FOOTHILLS WILL SEE AROUND 9 INCHES AT BONDURANT TO
5 INCHES IN PINEDALE. THE UPPER GREEN RIVER BASIN WILL SEE 3 TO 6
INCHES.

POST FRONTAL 7 TO 8MB...3 HOURLY SFC PRESSURE RISES WILL KEEP
POST FRONTAL NW WINDS UP THROUGH MID DAY SATURDAY IN THE 30 TO 40
MPH RANGE WITH GUSTS TO 50 MPH IN THE WIND RIVER BASIN AND NORTHERN
JOHNSON COUNTY. HIGH TEMPERATURES SUNDAY SHOULD BE 10 TO 15 DEGREES
COLDER SUNDAY THAN ON SATURDAY MOST AREAS. OCCASIONAL SNOWFALL WILL
CONTINUE THROUGH SUNDAY AND INTO MONDAY IN THE FAR WEST AS A SERIES
OF VORT LOBES PARADES WITHIN THE NORTHWEST FLOW WITH ONE DISTINCT
SHORTWAVE COMING THROUGH MONDAY. ON TUESDAY THE JET STREAM WILL PASS
OVERHEAD AS IT SLIDES OFF TO THE NORTHEAST OF US WHICH WILL PULL IN
MORE MOISTURE FROM THE NORTHWEST CONTINUING THE LIGHT TO
OCCASIONALLY MODERATE SNOW IN THE NORTHWEST MTNS. EXCEPT FOR SOME
CONTINUING LIGHT SNOW IN THE BIG HORN MTNS...AREAS EAST OF THE
DIVIDE WILL DRY OUT AFTER SATURDAY NIGHT. FOR THE REST OF THE
WEEK... TUESDAY NIGHT THROUGH THU...THE GFS AND THE EURO HAVE COME
MORE IN LINE WITH A HIGH PRESSURE RIDGE BUILDING IN FROM THE WEST
WITH A GRADUAL WARMING TREND. HOWEVER...WITH THE RIDGE AXIS STILL TO
THE WEST AND CONTINUING NW FLOW...WILL KEEP LOW POPS IN THE NORTHERN
AND CENTRAL MTNS FOR THIS TIME FRAME. WOULD RATHER WAIT FOR MORE RUN
TO RUN MODEL CONSISTENCY BEFORE WE WOULD BE WILLING TO TONE DOWN THE
MTN POPS ANY MORE THAN THEY ALREADY ARE...ESPECIALLY SINCE THIS IS A
SENSITIVE TIME OF THE MONTH GIVEN ALL THE HOLIDAY TRAVELERS.

&&

.AVIATION.../00Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES

VFR CONDITIONS EXPECTED ACROSS THE AREA THROUGH THE EVENING
HOURS...THOUGH PERIODS OF BREEZY WIND WILL BE FOUND AT KCPR AND
AREAS SOUTHWEST OF THE TERMINAL. THE APPROACHING WINTER SYSTEM
WILL CAUSE WIND SHEAR OVER MANY OF THE TERMINALS AFTER 08Z THIS
EVENING. LLWS HAS BEEN INCLUDED AT THE MAJORITY OF
TERMINALS...EXCEPT AT KCPR. UPPER LEVEL WIND WILL STILL BE STRONG
AT KCPR AS WELL...BUT WITH ALREADY STRONG SURFACE WIND
PRESENT...THE CHANGE BETWEEN SPEEDS AT THE LEVELS IS NOT AS
SIGNIFICANT. SNOWFALL WILL SPREAD ACROSS THE AREA THROUGH SATURDAY
AFTERNOON...WITH MOST TERMINALS SEEING AT LEAST VCSH BY 20Z. KCPR
IS THE EXCEPTION WITH SNOWFALL ANTICIPATED TO BEGIN AFTER 00Z
SUNDAY.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES

A FAIRLY MESSY AVIATION PERIOD AHEAD FOR AREAS WEST OF THE
CONTINENTAL DIVIDE. SNOWFALL ASSOCIATED WITH THE APPROACHING
WINTER SYSTEM WILL BEING TO IMPACT THE WESTERN MOUNTAINS AND
VALLEYS AFTER 03Z THIS EVENING...WITH PREVAILING -SN ANTICIPATED
AFTER 09Z AT KJAC. SNOWFALL WILL INTENSIFY AND INCREASE IN
COVERAGE THROUGH THE OVERNIGHT HOURS...WITH MOST TERMINALS SEEING
PREVAILING SNOW BY 14Z SATURDAY. ADDITIONALLY...STRONG WIND SHEAR
WILL BE PRESENT AT THE TERMINALS...ESPECIALLY AFTER 09Z THIS
EVENING. EXPECT INCREASED TURBULENCE OVER THE WESTERN AVIATION
PASSES...AND ALSO MOUNTAIN OBSCURATION WITH LOW CLOUDS AND ONGOING
SNOWFALL.

&&

.FIRE WEATHER...

A SIGNIFICANT WINTER WEATHER SYSTEM WILL BEGIN IMPACTING WESTERN
WYOMING THIS EVENING...AND SNOWFALL SPREADING TO INCLUDE MUCH OF
THE FORECAST AREA BY SATURDAY AFTERNOON. WINTER WEATHER HIGHLIGHTS
AREA IN EFFECT. ADDITIONALLY...STRONG WIND WILL DEVELOP ACROSS THE
WIND CORRIDOR BETWEEN ROCK SPRINGS AND CASPER...AND WILL ALSO
DEVELOP IN THE CODY FOOTHILLS. HIGH WIND WARNINGS ARE IN EFFECT
FOR MUCH OF THE DAY SATURDAY FOR THESE LOCATIONS. FIRE WEATHER
BEHAVIOR IS EXPECTED TO REMAIN MINIMAL UNDER THIS SYSTEM...WITH
THE BEST DISPERSION RATES OCCURRING DURING THE STORM. PLEASE SEE
THE APPROPRIATE WEATHER HIGHLIGHT PRODUCT FOR ADDITIONAL
INFORMATION REGARDING THE WINTER STORM AND HIGH WIND
WARNINGS...AND THE WINTER WEATHER ADVISORY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM 6 AM SATURDAY TO MIDNIGHT MST SATURDAY
NIGHT WYZ003-019-020-022.

WINTER WEATHER ADVISORY FROM 3 AM SATURDAY TO 6 AM MST SUNDAY
WYZ016-026-027.

WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 AM MST SUNDAY
WYZ001-002-012>015-023>025.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...LIPSON
AVIATION...BRANHAM
FIRE WEATHER...BRANHAM







000
FXUS65 KRIW 212142
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
242 PM MST FRI NOV 21 2014

.SHORT TERM...TONIGHT THROUGH SATURDAY

AN INTERESTING PERIOD. RELATIVELY BENIGN CONDITIONS EXPECTED
DURING THE EARLY EVENING HOURS TONIGHT...WITH A SIGNIFICANT WINTER
SYSTEM EXPECTED TO IMPACT THE AREA DURING THE OVERNIGHT HOURS.
SNOWFALL WILL BEGIN BEFORE MIDNIGHT...WITH ACTIVITY AND COVERAGE
INCREASING THROUGH THE OVERNIGHT HOURS. SNOWFALL RATES WILL
INCREASE DURING THE MORNING HOURS...ESPECIALLY BETWEEN 0500 AND
1100 SATURDAY. SNOWFALL ASSOCIATED WITH THIS SYSTEM WILL CONTINUE
IMPACT THE AREA THROUGH SATURDAY...WITH ACTIVITY SPREADING TO
INCLUDE PORTIONS OF SOUTHERN WYOMING DURING SATURDAY AFTERNOON.

SNOWFALL ACCUMULATIONS WILL BE SIGNIFICANT ACROSS THE WESTERN
MOUNTAINS AND VALLEYS...WITH SOME LESSER AMOUNTS EXPECTED ACROSS
SOUTHERN WYOMING. STORM STORM WILL CONTINUE INTO SATURDAY
NIGHT...WITH FURTHER DETAILS ON TOTAL ACCUMULATIONS COVERED IN THE
LONG TERM SECTION.

.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
THE SHORTWAVE EJECTED BY THE LOW SPINNING AROUND IN THE ALEUTIANS
WILL BE CROSSING OVER OUR AREA AROUND 06Z SATURDAY NIGHT. AFTER THE
FROPA...THE SNOWFALL INTENSITY WILL BEGIN TO DIMINISH IN THE WEST.
HOWEVER...MANY AREAS OF SWEETWATER COUNTY SHOULD SEE 2 TO 3 INCHES
OF SNOWFALL SATURDAY NIGHT FROM THE COMBINATION OF THE ASCT STRONG
PACIFIC COLD FRONT AND Q VECTOR FORCING. THE WIND RIVER BASIN ALMOST
ALWAYS MANAGES TO RECEIVE AT LEAST JUST UNDER AN INCH OF SNOWFALL
WHENEVER CENTRAL WYOMING RECEIVES THE BRUNT OF THE 700MB COLD PUNCH
FROM A CLASSIC CATAFRONT LIKE THIS ONE AS WILL BE THE CASE SATURDAY
NIGHT...SO INCREASED POPS THERE AS WELL AS ADDED CORRESPONDING SNOW
ACCUMULATIONS THERE. JOHNSON COUNTY IS ANOTHER AREA TO WATCH FOR
MORE PRECIP SINCE THAT AREA WILL BE CLOSER TO THE 700MB LOW TRACKING
EAST SOUTHEAST ACROSS NORTH DAKOTA BUT THE PRECIP THERE WILL START
AS RAIN SO NOT EXPECTING TOO MUCH IN THE WAY OF ACCUMULATING SNOW
THERE. SNOW TOTALS OF 3 TO 5 INCHES WILL BE COMMON IN THE BIG HORN
MTNS.

AS FAR AS SNOW TOTALS GO IN THE FAR WEST...BY 12Z SUNDAY MORNING WE
WILL BE LOOKING AT 12 TO 20 INCHES IN THE TETONS...GROS VENTRE
RANGE...SALT AND WYOMING RANGES AND ALONG AND WEST OF THE DIVIDE IN
THE WIND RIVER MTNS ALONG WITH LOCAL AMOUNTS OF UP TO 26 INCHES. THE
JACKSON VALLEY CAN EXPECT 8 TO 12 INCHES WITH THE HIGHEST AMOUNTS
EXPECTED IN THE NORTH. THE STAR VALLEY WILL SEE 6 TO 8 INCHES.
SOUTHERN LINCOLN COUNTY WILL SEE 2 TO 4 INCHES AROUND OPAL AND 4 TO
8 INCHES AROUND COKEVILLE. YELLOWSTONE PARK WILL HAVE SNOW TOTALS
RANGING FROM 16 INCHES IN THE SOUTHWEST TO 3 TO 8 INCHES IN THE
NORTH INCLUDING MAMMOTH. THE ABSAROKAS WILL SEE UP TO A FOOT IN THE
WEST TO MAINLY 3 TO 10 INCHES IN THE EAST. AREAS JUST WEST OF DUBOIS
WILL SEE 4 TO 8 INCHES WITH 1 TO 3 INCHES JUST TO THE EAST. THE
UPPER GREEN RIVER FOOTHILLS WILL SEE AROUND 9 INCHES AT BONDURANT TO
5 INCHES IN PINEDALE. THE UPPER GREEN RIVER BASIN WILL SEE 3 TO 6
INCHES.

POST FRONTAL 7 TO 8MB...3 HOURLY SFC PRESSURE RISES WILL KEEP
POST FRONTAL NW WINDS UP THROUGH MID DAY SATURDAY IN THE 30 TO 40
MPH RANGE WITH GUSTS TO 50 MPH IN THE WIND RIVER BASIN AND NORTHERN
JOHNSON COUNTY. HIGH TEMPERATURES SUNDAY SHOULD BE 10 TO 15 DEGREES
COLDER SUNDAY THAN ON SATURDAY MOST AREAS. OCCASIONAL SNOWFALL WILL
CONTINUE THROUGH SUNDAY AND INTO MONDAY IN THE FAR WEST AS A SERIES
OF VORT LOBES PARADES WITHIN THE NORTHWEST FLOW WITH ONE DISTINCT
SHORTWAVE COMING THROUGH MONDAY. ON TUESDAY THE JET STREAM WILL PASS
OVERHEAD AS IT SLIDES OFF TO THE NORTHEAST OF US WHICH WILL PULL IN
MORE MOISTURE FROM THE NORTHWEST CONTINUING THE LIGHT TO
OCCASIONALLY MODERATE SNOW IN THE NORTHWEST MTNS. EXCEPT FOR SOME
CONTINUING LIGHT SNOW IN THE BIG HORN MTNS...AREAS EAST OF THE
DIVIDE WILL DRY OUT AFTER SATURDAY NIGHT. FOR THE REST OF THE
WEEK... TUESDAY NIGHT THROUGH THU...THE GFS AND THE EURO HAVE COME
MORE IN LINE WITH A HIGH PRESSURE RIDGE BUILDING IN FROM THE WEST
WITH A GRADUAL WARMING TREND. HOWEVER...WITH THE RIDGE AXIS STILL TO
THE WEST AND CONTINUING NW FLOW...WILL KEEP LOW POPS IN THE NORTHERN
AND CENTRAL MTNS FOR THIS TIME FRAME. WOULD RATHER WAIT FOR MORE RUN
TO RUN MODEL CONSISTENCY BEFORE WE WOULD BE WILLING TO TONE DOWN THE
MTN POPS ANY MORE THAN THEY ALREADY ARE...ESPECIALLY SINCE THIS IS A
SENSITIVE TIME OF THE MONTH GIVEN ALL THE HOLIDAY TRAVELERS.

&&

.AVIATION.../00Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES

VFR CONDITIONS EXPECTED ACROSS THE AREA THROUGH THE EVENING
HOURS...THOUGH PERIODS OF BREEZY WIND WILL BE FOUND AT KCPR AND
AREAS SOUTHWEST OF THE TERMINAL. THE APPROACHING WINTER SYSTEM
WILL CAUSE WIND SHEAR OVER MANY OF THE TERMINALS AFTER 08Z THIS
EVENING. LLWS HAS BEEN INCLUDED AT THE MAJORITY OF
TERMINALS...EXCEPT AT KCPR. UPPER LEVEL WIND WILL STILL BE STRONG
AT KCPR AS WELL...BUT WITH ALREADY STRONG SURFACE WIND
PRESENT...THE CHANGE BETWEEN SPEEDS AT THE LEVELS IS NOT AS
SIGNIFICANT. SNOWFALL WILL SPREAD ACROSS THE AREA THROUGH SATURDAY
AFTERNOON...WITH MOST TERMINALS SEEING AT LEAST VCSH BY 20Z. KCPR
IS THE EXCEPTION WITH SNOWFALL ANTICIPATED TO BEGIN AFTER 00Z
SUNDAY.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES

A FAIRLY MESSY AVIATION PERIOD AHEAD FOR AREAS WEST OF THE
CONTINENTAL DIVIDE. SNOWFALL ASSOCIATED WITH THE APPROACHING
WINTER SYSTEM WILL BEING TO IMPACT THE WESTERN MOUNTAINS AND
VALLEYS AFTER 03Z THIS EVENING...WITH PREVAILING -SN ANTICIPATED
AFTER 09Z AT KJAC. SNOWFALL WILL INTENSIFY AND INCREASE IN
COVERAGE THROUGH THE OVERNIGHT HOURS...WITH MOST TERMINALS SEEING
PREVAILING SNOW BY 14Z SATURDAY. ADDITIONALLY...STRONG WIND SHEAR
WILL BE PRESENT AT THE TERMINALS...ESPECIALLY AFTER 09Z THIS
EVENING. EXPECT INCREASED TURBULENCE OVER THE WESTERN AVIATION
PASSES...AND ALSO MOUNTAIN OBSCURATION WITH LOW CLOUDS AND ONGOING
SNOWFALL.

&&

.FIRE WEATHER...

A SIGNIFICANT WINTER WEATHER SYSTEM WILL BEGIN IMPACTING WESTERN
WYOMING THIS EVENING...AND SNOWFALL SPREADING TO INCLUDE MUCH OF
THE FORECAST AREA BY SATURDAY AFTERNOON. WINTER WEATHER HIGHLIGHTS
AREA IN EFFECT. ADDITIONALLY...STRONG WIND WILL DEVELOP ACROSS THE
WIND CORRIDOR BETWEEN ROCK SPRINGS AND CASPER...AND WILL ALSO
DEVELOP IN THE CODY FOOTHILLS. HIGH WIND WARNINGS ARE IN EFFECT
FOR MUCH OF THE DAY SATURDAY FOR THESE LOCATIONS. FIRE WEATHER
BEHAVIOR IS EXPECTED TO REMAIN MINIMAL UNDER THIS SYSTEM...WITH
THE BEST DISPERSION RATES OCCURRING DURING THE STORM. PLEASE SEE
THE APPROPRIATE WEATHER HIGHLIGHT PRODUCT FOR ADDITIONAL
INFORMATION REGARDING THE WINTER STORM AND HIGH WIND
WARNINGS...AND THE WINTER WEATHER ADVISORY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM 6 AM SATURDAY TO MIDNIGHT MST SATURDAY
NIGHT WYZ003-019-020-022.

WINTER WEATHER ADVISORY FROM 3 AM SATURDAY TO 6 AM MST SUNDAY
WYZ016-026-027.

WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 AM MST SUNDAY
WYZ001-002-012>015-023>025.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...LIPSON
AVIATION...BRANHAM
FIRE WEATHER...BRANHAM








000
FXUS65 KCYS 211816
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1116 AM MST FRI NOV 21 2014

.UPDATE...
ISSUED AT 1109 AM MST FRI NOV 21 2014

MAIN CHANGE TO THE GRIDS THIS MORNING WAS TO INCREASE TEMPS SLIGHTLY
OVER THE HIGH PLAINS. OBSERVATIONS ARE ALREADY WARMER THAN EXPECTED
OWING TO GUSTY DOWNSLOPE WINDS EAST OF THE LARAMIE RANGE. NOT SURE
IT WILL GET MUCH WARMER THAN IT IS NOW AS SOME THICKER CLOUDS DRIFT
OVERHEAD. ALSO BUMPED UP WINDS A BIT WITH FCST SOUNDINGS SHOWING 30
TO 35 KTS OF FLOW AT THE TOP OF THE MIXED LAYER. OTHERWISE INHERITED
GRIDS ARE IN GOOD SHAPE. MAIN CHALLENGES WITH THE FULL AFTN PACKAGE
WILL BE HIGH WIND POTENTIAL AND MOUNTAIN SNOW. STAY TUNED.

&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

AN ACTIVE PATTERN IS SHAPING UP FOR THE FORECAST AREA THIS
WEEKEND...WITH STRONG WINDS AND MOUNTAIN SNOWS THE MAIN FORECAST
CHALLENGES.

TODAY WILL BE ONE LAST RELATIVELY CALM WEATHER DAY AHEAD OF THE
MAIN PACIFIC STORM SYSTEM THAT WILL SLAM INTO THE PAC NW TODAY AND
MAKE A SOUTHEASTWARD TREK ACROSS THE ROCKIES THROUGH SUNDAY.
MILD...BREEZY AND DRY CONDITIONS WILL OCCUR TODAY IN THE WAKE OF A
WEAK SHORTWAVE TROUGH MOVING OVERHEAD THIS MORNING. FAIRLY STRONG
PRESSURE FALLS OF 4-8 MB/6 HR ARE PROGGED AHEAD OF THE PACIFIC
STORM SYSTEM TONIGHT...WHICH WILL RAPIDLY STRENGTHEN THE SFC
PRESSURE GRADIENT ACROSS SOUTHEAST WYOMING. THE CAG-CPR GRADIENT
LOOKS TO REACH THE MID 60 DAM READINGS BY SUNRISE...AND PEAK TO
MID 80 DAM VALUES BY MIDDAY SATURDAY. THE LLVL INVERSION LOOKS TO
RAPIDLY WEAKEN AND LIFT TO MOUNTAIN TOP LEVEL EARLY SATURDAY
MORNING AS WELL...SO FEEL CONFIDENT THAT THE HIGH WIND EVENT
WILL OCCUR FOR PORTIONS OF SOUTHEAST WYOMING. ISSUED A HIGH WIND
WATCH...STARTING FIRST IN THE ARLINGTON AND BORDEAUX ZONES BEFORE
SUNRISE WHICH ARE MOST SENSITIVE TO RAPID STRENGTHENING OF THE
GRADIENT AND DEVELOPMENT OF MOUNTAIN WAVE ACTIVITY...THEN
EXPANDING TO NORTHERN CARBON AND ALBANY COUNTIES AND THE SOUTHERN
LARAMIE RANGE. LOOKING AT THE POTENTIAL FOR 60 TO 70 MPH GUSTS FOR
THESE AREAS THROUGH THE DAY...WITH PERHAPS SLIGHTLY STRONGER GUSTS
IN THE MORE FAVORED GAP LOCATIONS OF ARLINGTON AND BORDEAUX.
THERE IS POTENTIAL FOR THE NEED TO EXPAND THIS HIGHLIGHT TO THE
NORTHERN LARAMIE RANGE AND WESTERN CONVERSE COUNTY AS WELL...AS
GUIDANCE IS SHOWING RATHER STRONG H7 WINDS IN EXCESS OF 65 KTS
OVER THE NORTHERN LARAMIES. CONFIDENCE IS A BIT LOWER IN THIS
SOLUTION...SO WILL HOLD OFF FOR NOW. THE PACIFIC FRONT WILL MOVE
WEST - EAST ACROSS THE FORECAST AREA AROUND SUNSET ON
SATURDAY...WITH STRONG BORA WINDS CONTINUING FOR A FEW MORE HOURS
BEFORE DIMINISHING OVERNIGHT. COULD SEE GUSTY NORTHWEST WINDS
EXPAND TO THE WYO/NEB PLAINS ON SUNDAY AFTERNOON...AND WILL NEED
TO MONITOR FOR FUTURE HIGHLIGHTS FOR THESE AREA OVER THE COMING
DAY. TEMPERATURES ON SATURDAY WILL BE QUITE MILD OVERALL IN THE
MID 40S TO UPPER 50S FROM WEST TO EAST WITH WAA AND DOWNSLOPE
WINDS IN PLACE...AND WILL COOL FOR SUNDAY BEHIND THE FRONT.

ALONG WITH THE STRONG WINDS...MODERATE TO HEAVY SNOW IS EXPECTED TO
DEVELOP IN THE MOUNTAINS OF SOUTHEAST WYOMING AS THE SYSTEM MOVES
THROUGH SATURDAY AFTERNOON THROUGH SUNDAY. LFQ JET DYNAMICS WILL
INCREASE SATURDAY AFTERNOON ALONG WITH MIDLEVEL PVA...PACIFIC
MOISTURE AND LLVL OROGRAPHIC EFFECTS WITH THE STRONG WINDS IN
PLACE. THE STRONGEST MIDLEVEL VORT MAX WILL TRAVERSE ACROSS THE
CWA SATURDAY NIGHT...WHILE THE JET DIVES SOUTH INTO AZ/NM. SO
EXPECT A HEAVY SNOW EVENT SATURDAY AFTERNOON AND NIGHT...WITH
ACCUMULATIONS AROUND ONE FOOT POSSIBLE IN THE SNOWY AND SIERRA
MADRES. COULD SEE A FEW INCHES AS WELL IN SURROUNDING VALLEYS.
BLOWING SNOW WILL BE A CONCERN WITH STRONG LLVL WINDS IN
PLACE...ALTHOUGH THEY WILL WEAKEN THROUGH THE NIGHT. THE MAIN JET
DYNAMICS WILL THEN REMAIN SOUTH OF OUR AREA ON SUNDAY AND MONDAY
ALTHOUGH MIDLEVEL ENERGY AND PACIFIC MOISTURE WILL CONTINUE TO
STREAM OVERHEAD THROUGH THIS TIME...SO EXPECT CONTINUED PERIODS OF
MODERATE TO HEAVY SNOW TO CONTINUE THROUGH SUNDAY AND MONDAY. WENT
AHEAD AND ISSUED A LONG DURATION WINTER STORM WATCH FOR THE
COMBINATION OF STEADY MODERATE/HEAVY SNOWFALL AND GUSTY WINDS THAT
ARE ANTICIPATED SATURDAY AFTERNOON THROUGH MONDAY FOR THE SNOWY
AND SIERRAS. THE HIGHEST SNOW TOTALS WILL BE ALONG WEST AND
NORTHWEST FACING SLOPES. FURTHER EAST...DOWNSLOPE WARMING AND
DRYING EFFECTS WILL SEVERELY LIMIT PRECIP CHANCES...ALTHOUGH CANT
RULE OUT A FEW SHOWERS IN THE LARAMIE RANGE AND EAST CENTRAL
WYOMING ESPECIALLY WITH THE MAIN PACIFIC FRONT SATURDAY NIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

SUNDAY NIGHT/MONDAY...MOIST NORTHWEST FLOW ALOFT WILL PRODUCE
SCATTERED TO NUMEROUS SNOW SHOWERS OVER THE SNOWY AND SIERRA MADRE
RANGES...MAINLY DRY ELSEWHERE. WINDY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS AND UNIDIRECTIONAL NORTHWEST WINDS.

TUESDAY...NORTHWEST FLOW ALOFT EVEN STRONGER...AND BASED ON
PROJECTED SURFACE THROUGH 700 MB HEIGHTS...SOME AREAS WILL LIKELY
SEE HIGH WIND CRITERIA. SLIGHT DECREASE IN MID LEVEL MOISTURE...THUS
SNOW COVERAGE ACROSS THE SNOWY AND SIERRA MADRE RANGES SHOULD BE
MORE LIMITED.

WEDNESDAY...ANOTHER QUITE WINDY DAY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS. RELATIVELY MILD PER 850 MB AND 700 TEMPERATURES AND
DOWNSLOPE WARMING. ISOLATED TO SCATTERED SNOWS ACROSS OUR NORTHERN
COUNTIES FROM DOUGLAS TO LUSK TO CHADRON.

THANKSGIVING...THE MODELS ARE NOW SHOWING WEST NORTHWEST FLOW ALOFT
WITH OUR COUNTIES IN THE WARM SECTOR...ALONG WITH DOWNSLOPE WEST
WINDS. WILL BLEND WITH OUR NEIGHBORING OFFICE AND KEEP HIGH
TEMPERATURES DOWN...THOUGH LATER SHIFTS WILL NEED TO BETTER ASSESS
THE SITUATION.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1109 AM MST FRI NOV 21 2014

MAIN AVIATION CONCERNS WILL FOCUS ON WINDS LATER TONIGHT AND INTO
TOMORROW. WILL ALSO SEE SNOW DEVELOP OVER THE MOUNTAINS TOMORROW.
STRONG WINDS WITH FREQUENT GUSTS TO 50 KTS WILL DEVELOP IN THE
ARLINGTON AREA AND INTO THE BORDEAUX AREA LATE TONIGHT. THESE
STRONG WEST TO SOUTHWEST WINDS WILL THEN SPREAD INTO THE SOUTHERN
AND NORTHERN LARAMIE RANGES TOWARD SUNRISE SATURDAY. GUSTY WINDS
WILL ALSO SPREAD INTO LOWER ELEVATIONS AND INTO THE PLAINS OF
SOUTHEAST WYOMING SATURDAY AFTERNOON WITH GUSTS OF 30 TO 40 KTS
BEING COMMON. WINDS WILL NOT BE AS STRONG INTO THE NEBRASKA
PANHANDLE BUT STILL BREEZY TO WINDY SATURDAY AFTERNOON.

MOUNTAINS WILL BE OBSCURED DUE TO FALLING AND BLOWING SNOW
SATURDAY AFTERNOON...ESPECIALLY INTO THE SNOWY AND SIERRA MADRE
RANGES WHERE A WINTER STORM WATCH IS CURRENTLY IN EFFECT. PERIODS
OF SNOW WILL CONTINUE INTO MONDAY ACROSS THESE MOUNTAINS.


&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING
     FOR WYZ104-105-116-117.

     HIGH WIND WATCH FROM LATE TONIGHT THROUGH SATURDAY EVENING FOR
     WYZ106-110.

NE...NONE.

&&

$$

UPDATE...CLH
SHORT TERM...RJM
LONG TERM...SAR
AVIATION...SML
FIRE WEATHER...RJM



000
FXUS65 KCYS 211816
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1116 AM MST FRI NOV 21 2014

.UPDATE...
ISSUED AT 1109 AM MST FRI NOV 21 2014

MAIN CHANGE TO THE GRIDS THIS MORNING WAS TO INCREASE TEMPS SLIGHTLY
OVER THE HIGH PLAINS. OBSERVATIONS ARE ALREADY WARMER THAN EXPECTED
OWING TO GUSTY DOWNSLOPE WINDS EAST OF THE LARAMIE RANGE. NOT SURE
IT WILL GET MUCH WARMER THAN IT IS NOW AS SOME THICKER CLOUDS DRIFT
OVERHEAD. ALSO BUMPED UP WINDS A BIT WITH FCST SOUNDINGS SHOWING 30
TO 35 KTS OF FLOW AT THE TOP OF THE MIXED LAYER. OTHERWISE INHERITED
GRIDS ARE IN GOOD SHAPE. MAIN CHALLENGES WITH THE FULL AFTN PACKAGE
WILL BE HIGH WIND POTENTIAL AND MOUNTAIN SNOW. STAY TUNED.

&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

AN ACTIVE PATTERN IS SHAPING UP FOR THE FORECAST AREA THIS
WEEKEND...WITH STRONG WINDS AND MOUNTAIN SNOWS THE MAIN FORECAST
CHALLENGES.

TODAY WILL BE ONE LAST RELATIVELY CALM WEATHER DAY AHEAD OF THE
MAIN PACIFIC STORM SYSTEM THAT WILL SLAM INTO THE PAC NW TODAY AND
MAKE A SOUTHEASTWARD TREK ACROSS THE ROCKIES THROUGH SUNDAY.
MILD...BREEZY AND DRY CONDITIONS WILL OCCUR TODAY IN THE WAKE OF A
WEAK SHORTWAVE TROUGH MOVING OVERHEAD THIS MORNING. FAIRLY STRONG
PRESSURE FALLS OF 4-8 MB/6 HR ARE PROGGED AHEAD OF THE PACIFIC
STORM SYSTEM TONIGHT...WHICH WILL RAPIDLY STRENGTHEN THE SFC
PRESSURE GRADIENT ACROSS SOUTHEAST WYOMING. THE CAG-CPR GRADIENT
LOOKS TO REACH THE MID 60 DAM READINGS BY SUNRISE...AND PEAK TO
MID 80 DAM VALUES BY MIDDAY SATURDAY. THE LLVL INVERSION LOOKS TO
RAPIDLY WEAKEN AND LIFT TO MOUNTAIN TOP LEVEL EARLY SATURDAY
MORNING AS WELL...SO FEEL CONFIDENT THAT THE HIGH WIND EVENT
WILL OCCUR FOR PORTIONS OF SOUTHEAST WYOMING. ISSUED A HIGH WIND
WATCH...STARTING FIRST IN THE ARLINGTON AND BORDEAUX ZONES BEFORE
SUNRISE WHICH ARE MOST SENSITIVE TO RAPID STRENGTHENING OF THE
GRADIENT AND DEVELOPMENT OF MOUNTAIN WAVE ACTIVITY...THEN
EXPANDING TO NORTHERN CARBON AND ALBANY COUNTIES AND THE SOUTHERN
LARAMIE RANGE. LOOKING AT THE POTENTIAL FOR 60 TO 70 MPH GUSTS FOR
THESE AREAS THROUGH THE DAY...WITH PERHAPS SLIGHTLY STRONGER GUSTS
IN THE MORE FAVORED GAP LOCATIONS OF ARLINGTON AND BORDEAUX.
THERE IS POTENTIAL FOR THE NEED TO EXPAND THIS HIGHLIGHT TO THE
NORTHERN LARAMIE RANGE AND WESTERN CONVERSE COUNTY AS WELL...AS
GUIDANCE IS SHOWING RATHER STRONG H7 WINDS IN EXCESS OF 65 KTS
OVER THE NORTHERN LARAMIES. CONFIDENCE IS A BIT LOWER IN THIS
SOLUTION...SO WILL HOLD OFF FOR NOW. THE PACIFIC FRONT WILL MOVE
WEST - EAST ACROSS THE FORECAST AREA AROUND SUNSET ON
SATURDAY...WITH STRONG BORA WINDS CONTINUING FOR A FEW MORE HOURS
BEFORE DIMINISHING OVERNIGHT. COULD SEE GUSTY NORTHWEST WINDS
EXPAND TO THE WYO/NEB PLAINS ON SUNDAY AFTERNOON...AND WILL NEED
TO MONITOR FOR FUTURE HIGHLIGHTS FOR THESE AREA OVER THE COMING
DAY. TEMPERATURES ON SATURDAY WILL BE QUITE MILD OVERALL IN THE
MID 40S TO UPPER 50S FROM WEST TO EAST WITH WAA AND DOWNSLOPE
WINDS IN PLACE...AND WILL COOL FOR SUNDAY BEHIND THE FRONT.

ALONG WITH THE STRONG WINDS...MODERATE TO HEAVY SNOW IS EXPECTED TO
DEVELOP IN THE MOUNTAINS OF SOUTHEAST WYOMING AS THE SYSTEM MOVES
THROUGH SATURDAY AFTERNOON THROUGH SUNDAY. LFQ JET DYNAMICS WILL
INCREASE SATURDAY AFTERNOON ALONG WITH MIDLEVEL PVA...PACIFIC
MOISTURE AND LLVL OROGRAPHIC EFFECTS WITH THE STRONG WINDS IN
PLACE. THE STRONGEST MIDLEVEL VORT MAX WILL TRAVERSE ACROSS THE
CWA SATURDAY NIGHT...WHILE THE JET DIVES SOUTH INTO AZ/NM. SO
EXPECT A HEAVY SNOW EVENT SATURDAY AFTERNOON AND NIGHT...WITH
ACCUMULATIONS AROUND ONE FOOT POSSIBLE IN THE SNOWY AND SIERRA
MADRES. COULD SEE A FEW INCHES AS WELL IN SURROUNDING VALLEYS.
BLOWING SNOW WILL BE A CONCERN WITH STRONG LLVL WINDS IN
PLACE...ALTHOUGH THEY WILL WEAKEN THROUGH THE NIGHT. THE MAIN JET
DYNAMICS WILL THEN REMAIN SOUTH OF OUR AREA ON SUNDAY AND MONDAY
ALTHOUGH MIDLEVEL ENERGY AND PACIFIC MOISTURE WILL CONTINUE TO
STREAM OVERHEAD THROUGH THIS TIME...SO EXPECT CONTINUED PERIODS OF
MODERATE TO HEAVY SNOW TO CONTINUE THROUGH SUNDAY AND MONDAY. WENT
AHEAD AND ISSUED A LONG DURATION WINTER STORM WATCH FOR THE
COMBINATION OF STEADY MODERATE/HEAVY SNOWFALL AND GUSTY WINDS THAT
ARE ANTICIPATED SATURDAY AFTERNOON THROUGH MONDAY FOR THE SNOWY
AND SIERRAS. THE HIGHEST SNOW TOTALS WILL BE ALONG WEST AND
NORTHWEST FACING SLOPES. FURTHER EAST...DOWNSLOPE WARMING AND
DRYING EFFECTS WILL SEVERELY LIMIT PRECIP CHANCES...ALTHOUGH CANT
RULE OUT A FEW SHOWERS IN THE LARAMIE RANGE AND EAST CENTRAL
WYOMING ESPECIALLY WITH THE MAIN PACIFIC FRONT SATURDAY NIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

SUNDAY NIGHT/MONDAY...MOIST NORTHWEST FLOW ALOFT WILL PRODUCE
SCATTERED TO NUMEROUS SNOW SHOWERS OVER THE SNOWY AND SIERRA MADRE
RANGES...MAINLY DRY ELSEWHERE. WINDY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS AND UNIDIRECTIONAL NORTHWEST WINDS.

TUESDAY...NORTHWEST FLOW ALOFT EVEN STRONGER...AND BASED ON
PROJECTED SURFACE THROUGH 700 MB HEIGHTS...SOME AREAS WILL LIKELY
SEE HIGH WIND CRITERIA. SLIGHT DECREASE IN MID LEVEL MOISTURE...THUS
SNOW COVERAGE ACROSS THE SNOWY AND SIERRA MADRE RANGES SHOULD BE
MORE LIMITED.

WEDNESDAY...ANOTHER QUITE WINDY DAY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS. RELATIVELY MILD PER 850 MB AND 700 TEMPERATURES AND
DOWNSLOPE WARMING. ISOLATED TO SCATTERED SNOWS ACROSS OUR NORTHERN
COUNTIES FROM DOUGLAS TO LUSK TO CHADRON.

THANKSGIVING...THE MODELS ARE NOW SHOWING WEST NORTHWEST FLOW ALOFT
WITH OUR COUNTIES IN THE WARM SECTOR...ALONG WITH DOWNSLOPE WEST
WINDS. WILL BLEND WITH OUR NEIGHBORING OFFICE AND KEEP HIGH
TEMPERATURES DOWN...THOUGH LATER SHIFTS WILL NEED TO BETTER ASSESS
THE SITUATION.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1109 AM MST FRI NOV 21 2014

MAIN AVIATION CONCERNS WILL FOCUS ON WINDS LATER TONIGHT AND INTO
TOMORROW. WILL ALSO SEE SNOW DEVELOP OVER THE MOUNTAINS TOMORROW.
STRONG WINDS WITH FREQUENT GUSTS TO 50 KTS WILL DEVELOP IN THE
ARLINGTON AREA AND INTO THE BORDEAUX AREA LATE TONIGHT. THESE
STRONG WEST TO SOUTHWEST WINDS WILL THEN SPREAD INTO THE SOUTHERN
AND NORTHERN LARAMIE RANGES TOWARD SUNRISE SATURDAY. GUSTY WINDS
WILL ALSO SPREAD INTO LOWER ELEVATIONS AND INTO THE PLAINS OF
SOUTHEAST WYOMING SATURDAY AFTERNOON WITH GUSTS OF 30 TO 40 KTS
BEING COMMON. WINDS WILL NOT BE AS STRONG INTO THE NEBRASKA
PANHANDLE BUT STILL BREEZY TO WINDY SATURDAY AFTERNOON.

MOUNTAINS WILL BE OBSCURED DUE TO FALLING AND BLOWING SNOW
SATURDAY AFTERNOON...ESPECIALLY INTO THE SNOWY AND SIERRA MADRE
RANGES WHERE A WINTER STORM WATCH IS CURRENTLY IN EFFECT. PERIODS
OF SNOW WILL CONTINUE INTO MONDAY ACROSS THESE MOUNTAINS.


&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING
     FOR WYZ104-105-116-117.

     HIGH WIND WATCH FROM LATE TONIGHT THROUGH SATURDAY EVENING FOR
     WYZ106-110.

NE...NONE.

&&

$$

UPDATE...CLH
SHORT TERM...RJM
LONG TERM...SAR
AVIATION...SML
FIRE WEATHER...RJM



000
FXUS65 KCYS 211816
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1116 AM MST FRI NOV 21 2014

.UPDATE...
ISSUED AT 1109 AM MST FRI NOV 21 2014

MAIN CHANGE TO THE GRIDS THIS MORNING WAS TO INCREASE TEMPS SLIGHTLY
OVER THE HIGH PLAINS. OBSERVATIONS ARE ALREADY WARMER THAN EXPECTED
OWING TO GUSTY DOWNSLOPE WINDS EAST OF THE LARAMIE RANGE. NOT SURE
IT WILL GET MUCH WARMER THAN IT IS NOW AS SOME THICKER CLOUDS DRIFT
OVERHEAD. ALSO BUMPED UP WINDS A BIT WITH FCST SOUNDINGS SHOWING 30
TO 35 KTS OF FLOW AT THE TOP OF THE MIXED LAYER. OTHERWISE INHERITED
GRIDS ARE IN GOOD SHAPE. MAIN CHALLENGES WITH THE FULL AFTN PACKAGE
WILL BE HIGH WIND POTENTIAL AND MOUNTAIN SNOW. STAY TUNED.

&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

AN ACTIVE PATTERN IS SHAPING UP FOR THE FORECAST AREA THIS
WEEKEND...WITH STRONG WINDS AND MOUNTAIN SNOWS THE MAIN FORECAST
CHALLENGES.

TODAY WILL BE ONE LAST RELATIVELY CALM WEATHER DAY AHEAD OF THE
MAIN PACIFIC STORM SYSTEM THAT WILL SLAM INTO THE PAC NW TODAY AND
MAKE A SOUTHEASTWARD TREK ACROSS THE ROCKIES THROUGH SUNDAY.
MILD...BREEZY AND DRY CONDITIONS WILL OCCUR TODAY IN THE WAKE OF A
WEAK SHORTWAVE TROUGH MOVING OVERHEAD THIS MORNING. FAIRLY STRONG
PRESSURE FALLS OF 4-8 MB/6 HR ARE PROGGED AHEAD OF THE PACIFIC
STORM SYSTEM TONIGHT...WHICH WILL RAPIDLY STRENGTHEN THE SFC
PRESSURE GRADIENT ACROSS SOUTHEAST WYOMING. THE CAG-CPR GRADIENT
LOOKS TO REACH THE MID 60 DAM READINGS BY SUNRISE...AND PEAK TO
MID 80 DAM VALUES BY MIDDAY SATURDAY. THE LLVL INVERSION LOOKS TO
RAPIDLY WEAKEN AND LIFT TO MOUNTAIN TOP LEVEL EARLY SATURDAY
MORNING AS WELL...SO FEEL CONFIDENT THAT THE HIGH WIND EVENT
WILL OCCUR FOR PORTIONS OF SOUTHEAST WYOMING. ISSUED A HIGH WIND
WATCH...STARTING FIRST IN THE ARLINGTON AND BORDEAUX ZONES BEFORE
SUNRISE WHICH ARE MOST SENSITIVE TO RAPID STRENGTHENING OF THE
GRADIENT AND DEVELOPMENT OF MOUNTAIN WAVE ACTIVITY...THEN
EXPANDING TO NORTHERN CARBON AND ALBANY COUNTIES AND THE SOUTHERN
LARAMIE RANGE. LOOKING AT THE POTENTIAL FOR 60 TO 70 MPH GUSTS FOR
THESE AREAS THROUGH THE DAY...WITH PERHAPS SLIGHTLY STRONGER GUSTS
IN THE MORE FAVORED GAP LOCATIONS OF ARLINGTON AND BORDEAUX.
THERE IS POTENTIAL FOR THE NEED TO EXPAND THIS HIGHLIGHT TO THE
NORTHERN LARAMIE RANGE AND WESTERN CONVERSE COUNTY AS WELL...AS
GUIDANCE IS SHOWING RATHER STRONG H7 WINDS IN EXCESS OF 65 KTS
OVER THE NORTHERN LARAMIES. CONFIDENCE IS A BIT LOWER IN THIS
SOLUTION...SO WILL HOLD OFF FOR NOW. THE PACIFIC FRONT WILL MOVE
WEST - EAST ACROSS THE FORECAST AREA AROUND SUNSET ON
SATURDAY...WITH STRONG BORA WINDS CONTINUING FOR A FEW MORE HOURS
BEFORE DIMINISHING OVERNIGHT. COULD SEE GUSTY NORTHWEST WINDS
EXPAND TO THE WYO/NEB PLAINS ON SUNDAY AFTERNOON...AND WILL NEED
TO MONITOR FOR FUTURE HIGHLIGHTS FOR THESE AREA OVER THE COMING
DAY. TEMPERATURES ON SATURDAY WILL BE QUITE MILD OVERALL IN THE
MID 40S TO UPPER 50S FROM WEST TO EAST WITH WAA AND DOWNSLOPE
WINDS IN PLACE...AND WILL COOL FOR SUNDAY BEHIND THE FRONT.

ALONG WITH THE STRONG WINDS...MODERATE TO HEAVY SNOW IS EXPECTED TO
DEVELOP IN THE MOUNTAINS OF SOUTHEAST WYOMING AS THE SYSTEM MOVES
THROUGH SATURDAY AFTERNOON THROUGH SUNDAY. LFQ JET DYNAMICS WILL
INCREASE SATURDAY AFTERNOON ALONG WITH MIDLEVEL PVA...PACIFIC
MOISTURE AND LLVL OROGRAPHIC EFFECTS WITH THE STRONG WINDS IN
PLACE. THE STRONGEST MIDLEVEL VORT MAX WILL TRAVERSE ACROSS THE
CWA SATURDAY NIGHT...WHILE THE JET DIVES SOUTH INTO AZ/NM. SO
EXPECT A HEAVY SNOW EVENT SATURDAY AFTERNOON AND NIGHT...WITH
ACCUMULATIONS AROUND ONE FOOT POSSIBLE IN THE SNOWY AND SIERRA
MADRES. COULD SEE A FEW INCHES AS WELL IN SURROUNDING VALLEYS.
BLOWING SNOW WILL BE A CONCERN WITH STRONG LLVL WINDS IN
PLACE...ALTHOUGH THEY WILL WEAKEN THROUGH THE NIGHT. THE MAIN JET
DYNAMICS WILL THEN REMAIN SOUTH OF OUR AREA ON SUNDAY AND MONDAY
ALTHOUGH MIDLEVEL ENERGY AND PACIFIC MOISTURE WILL CONTINUE TO
STREAM OVERHEAD THROUGH THIS TIME...SO EXPECT CONTINUED PERIODS OF
MODERATE TO HEAVY SNOW TO CONTINUE THROUGH SUNDAY AND MONDAY. WENT
AHEAD AND ISSUED A LONG DURATION WINTER STORM WATCH FOR THE
COMBINATION OF STEADY MODERATE/HEAVY SNOWFALL AND GUSTY WINDS THAT
ARE ANTICIPATED SATURDAY AFTERNOON THROUGH MONDAY FOR THE SNOWY
AND SIERRAS. THE HIGHEST SNOW TOTALS WILL BE ALONG WEST AND
NORTHWEST FACING SLOPES. FURTHER EAST...DOWNSLOPE WARMING AND
DRYING EFFECTS WILL SEVERELY LIMIT PRECIP CHANCES...ALTHOUGH CANT
RULE OUT A FEW SHOWERS IN THE LARAMIE RANGE AND EAST CENTRAL
WYOMING ESPECIALLY WITH THE MAIN PACIFIC FRONT SATURDAY NIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

SUNDAY NIGHT/MONDAY...MOIST NORTHWEST FLOW ALOFT WILL PRODUCE
SCATTERED TO NUMEROUS SNOW SHOWERS OVER THE SNOWY AND SIERRA MADRE
RANGES...MAINLY DRY ELSEWHERE. WINDY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS AND UNIDIRECTIONAL NORTHWEST WINDS.

TUESDAY...NORTHWEST FLOW ALOFT EVEN STRONGER...AND BASED ON
PROJECTED SURFACE THROUGH 700 MB HEIGHTS...SOME AREAS WILL LIKELY
SEE HIGH WIND CRITERIA. SLIGHT DECREASE IN MID LEVEL MOISTURE...THUS
SNOW COVERAGE ACROSS THE SNOWY AND SIERRA MADRE RANGES SHOULD BE
MORE LIMITED.

WEDNESDAY...ANOTHER QUITE WINDY DAY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS. RELATIVELY MILD PER 850 MB AND 700 TEMPERATURES AND
DOWNSLOPE WARMING. ISOLATED TO SCATTERED SNOWS ACROSS OUR NORTHERN
COUNTIES FROM DOUGLAS TO LUSK TO CHADRON.

THANKSGIVING...THE MODELS ARE NOW SHOWING WEST NORTHWEST FLOW ALOFT
WITH OUR COUNTIES IN THE WARM SECTOR...ALONG WITH DOWNSLOPE WEST
WINDS. WILL BLEND WITH OUR NEIGHBORING OFFICE AND KEEP HIGH
TEMPERATURES DOWN...THOUGH LATER SHIFTS WILL NEED TO BETTER ASSESS
THE SITUATION.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1109 AM MST FRI NOV 21 2014

MAIN AVIATION CONCERNS WILL FOCUS ON WINDS LATER TONIGHT AND INTO
TOMORROW. WILL ALSO SEE SNOW DEVELOP OVER THE MOUNTAINS TOMORROW.
STRONG WINDS WITH FREQUENT GUSTS TO 50 KTS WILL DEVELOP IN THE
ARLINGTON AREA AND INTO THE BORDEAUX AREA LATE TONIGHT. THESE
STRONG WEST TO SOUTHWEST WINDS WILL THEN SPREAD INTO THE SOUTHERN
AND NORTHERN LARAMIE RANGES TOWARD SUNRISE SATURDAY. GUSTY WINDS
WILL ALSO SPREAD INTO LOWER ELEVATIONS AND INTO THE PLAINS OF
SOUTHEAST WYOMING SATURDAY AFTERNOON WITH GUSTS OF 30 TO 40 KTS
BEING COMMON. WINDS WILL NOT BE AS STRONG INTO THE NEBRASKA
PANHANDLE BUT STILL BREEZY TO WINDY SATURDAY AFTERNOON.

MOUNTAINS WILL BE OBSCURED DUE TO FALLING AND BLOWING SNOW
SATURDAY AFTERNOON...ESPECIALLY INTO THE SNOWY AND SIERRA MADRE
RANGES WHERE A WINTER STORM WATCH IS CURRENTLY IN EFFECT. PERIODS
OF SNOW WILL CONTINUE INTO MONDAY ACROSS THESE MOUNTAINS.


&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING
     FOR WYZ104-105-116-117.

     HIGH WIND WATCH FROM LATE TONIGHT THROUGH SATURDAY EVENING FOR
     WYZ106-110.

NE...NONE.

&&

$$

UPDATE...CLH
SHORT TERM...RJM
LONG TERM...SAR
AVIATION...SML
FIRE WEATHER...RJM



000
FXUS65 KCYS 211816
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1116 AM MST FRI NOV 21 2014

.UPDATE...
ISSUED AT 1109 AM MST FRI NOV 21 2014

MAIN CHANGE TO THE GRIDS THIS MORNING WAS TO INCREASE TEMPS SLIGHTLY
OVER THE HIGH PLAINS. OBSERVATIONS ARE ALREADY WARMER THAN EXPECTED
OWING TO GUSTY DOWNSLOPE WINDS EAST OF THE LARAMIE RANGE. NOT SURE
IT WILL GET MUCH WARMER THAN IT IS NOW AS SOME THICKER CLOUDS DRIFT
OVERHEAD. ALSO BUMPED UP WINDS A BIT WITH FCST SOUNDINGS SHOWING 30
TO 35 KTS OF FLOW AT THE TOP OF THE MIXED LAYER. OTHERWISE INHERITED
GRIDS ARE IN GOOD SHAPE. MAIN CHALLENGES WITH THE FULL AFTN PACKAGE
WILL BE HIGH WIND POTENTIAL AND MOUNTAIN SNOW. STAY TUNED.

&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

AN ACTIVE PATTERN IS SHAPING UP FOR THE FORECAST AREA THIS
WEEKEND...WITH STRONG WINDS AND MOUNTAIN SNOWS THE MAIN FORECAST
CHALLENGES.

TODAY WILL BE ONE LAST RELATIVELY CALM WEATHER DAY AHEAD OF THE
MAIN PACIFIC STORM SYSTEM THAT WILL SLAM INTO THE PAC NW TODAY AND
MAKE A SOUTHEASTWARD TREK ACROSS THE ROCKIES THROUGH SUNDAY.
MILD...BREEZY AND DRY CONDITIONS WILL OCCUR TODAY IN THE WAKE OF A
WEAK SHORTWAVE TROUGH MOVING OVERHEAD THIS MORNING. FAIRLY STRONG
PRESSURE FALLS OF 4-8 MB/6 HR ARE PROGGED AHEAD OF THE PACIFIC
STORM SYSTEM TONIGHT...WHICH WILL RAPIDLY STRENGTHEN THE SFC
PRESSURE GRADIENT ACROSS SOUTHEAST WYOMING. THE CAG-CPR GRADIENT
LOOKS TO REACH THE MID 60 DAM READINGS BY SUNRISE...AND PEAK TO
MID 80 DAM VALUES BY MIDDAY SATURDAY. THE LLVL INVERSION LOOKS TO
RAPIDLY WEAKEN AND LIFT TO MOUNTAIN TOP LEVEL EARLY SATURDAY
MORNING AS WELL...SO FEEL CONFIDENT THAT THE HIGH WIND EVENT
WILL OCCUR FOR PORTIONS OF SOUTHEAST WYOMING. ISSUED A HIGH WIND
WATCH...STARTING FIRST IN THE ARLINGTON AND BORDEAUX ZONES BEFORE
SUNRISE WHICH ARE MOST SENSITIVE TO RAPID STRENGTHENING OF THE
GRADIENT AND DEVELOPMENT OF MOUNTAIN WAVE ACTIVITY...THEN
EXPANDING TO NORTHERN CARBON AND ALBANY COUNTIES AND THE SOUTHERN
LARAMIE RANGE. LOOKING AT THE POTENTIAL FOR 60 TO 70 MPH GUSTS FOR
THESE AREAS THROUGH THE DAY...WITH PERHAPS SLIGHTLY STRONGER GUSTS
IN THE MORE FAVORED GAP LOCATIONS OF ARLINGTON AND BORDEAUX.
THERE IS POTENTIAL FOR THE NEED TO EXPAND THIS HIGHLIGHT TO THE
NORTHERN LARAMIE RANGE AND WESTERN CONVERSE COUNTY AS WELL...AS
GUIDANCE IS SHOWING RATHER STRONG H7 WINDS IN EXCESS OF 65 KTS
OVER THE NORTHERN LARAMIES. CONFIDENCE IS A BIT LOWER IN THIS
SOLUTION...SO WILL HOLD OFF FOR NOW. THE PACIFIC FRONT WILL MOVE
WEST - EAST ACROSS THE FORECAST AREA AROUND SUNSET ON
SATURDAY...WITH STRONG BORA WINDS CONTINUING FOR A FEW MORE HOURS
BEFORE DIMINISHING OVERNIGHT. COULD SEE GUSTY NORTHWEST WINDS
EXPAND TO THE WYO/NEB PLAINS ON SUNDAY AFTERNOON...AND WILL NEED
TO MONITOR FOR FUTURE HIGHLIGHTS FOR THESE AREA OVER THE COMING
DAY. TEMPERATURES ON SATURDAY WILL BE QUITE MILD OVERALL IN THE
MID 40S TO UPPER 50S FROM WEST TO EAST WITH WAA AND DOWNSLOPE
WINDS IN PLACE...AND WILL COOL FOR SUNDAY BEHIND THE FRONT.

ALONG WITH THE STRONG WINDS...MODERATE TO HEAVY SNOW IS EXPECTED TO
DEVELOP IN THE MOUNTAINS OF SOUTHEAST WYOMING AS THE SYSTEM MOVES
THROUGH SATURDAY AFTERNOON THROUGH SUNDAY. LFQ JET DYNAMICS WILL
INCREASE SATURDAY AFTERNOON ALONG WITH MIDLEVEL PVA...PACIFIC
MOISTURE AND LLVL OROGRAPHIC EFFECTS WITH THE STRONG WINDS IN
PLACE. THE STRONGEST MIDLEVEL VORT MAX WILL TRAVERSE ACROSS THE
CWA SATURDAY NIGHT...WHILE THE JET DIVES SOUTH INTO AZ/NM. SO
EXPECT A HEAVY SNOW EVENT SATURDAY AFTERNOON AND NIGHT...WITH
ACCUMULATIONS AROUND ONE FOOT POSSIBLE IN THE SNOWY AND SIERRA
MADRES. COULD SEE A FEW INCHES AS WELL IN SURROUNDING VALLEYS.
BLOWING SNOW WILL BE A CONCERN WITH STRONG LLVL WINDS IN
PLACE...ALTHOUGH THEY WILL WEAKEN THROUGH THE NIGHT. THE MAIN JET
DYNAMICS WILL THEN REMAIN SOUTH OF OUR AREA ON SUNDAY AND MONDAY
ALTHOUGH MIDLEVEL ENERGY AND PACIFIC MOISTURE WILL CONTINUE TO
STREAM OVERHEAD THROUGH THIS TIME...SO EXPECT CONTINUED PERIODS OF
MODERATE TO HEAVY SNOW TO CONTINUE THROUGH SUNDAY AND MONDAY. WENT
AHEAD AND ISSUED A LONG DURATION WINTER STORM WATCH FOR THE
COMBINATION OF STEADY MODERATE/HEAVY SNOWFALL AND GUSTY WINDS THAT
ARE ANTICIPATED SATURDAY AFTERNOON THROUGH MONDAY FOR THE SNOWY
AND SIERRAS. THE HIGHEST SNOW TOTALS WILL BE ALONG WEST AND
NORTHWEST FACING SLOPES. FURTHER EAST...DOWNSLOPE WARMING AND
DRYING EFFECTS WILL SEVERELY LIMIT PRECIP CHANCES...ALTHOUGH CANT
RULE OUT A FEW SHOWERS IN THE LARAMIE RANGE AND EAST CENTRAL
WYOMING ESPECIALLY WITH THE MAIN PACIFIC FRONT SATURDAY NIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

SUNDAY NIGHT/MONDAY...MOIST NORTHWEST FLOW ALOFT WILL PRODUCE
SCATTERED TO NUMEROUS SNOW SHOWERS OVER THE SNOWY AND SIERRA MADRE
RANGES...MAINLY DRY ELSEWHERE. WINDY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS AND UNIDIRECTIONAL NORTHWEST WINDS.

TUESDAY...NORTHWEST FLOW ALOFT EVEN STRONGER...AND BASED ON
PROJECTED SURFACE THROUGH 700 MB HEIGHTS...SOME AREAS WILL LIKELY
SEE HIGH WIND CRITERIA. SLIGHT DECREASE IN MID LEVEL MOISTURE...THUS
SNOW COVERAGE ACROSS THE SNOWY AND SIERRA MADRE RANGES SHOULD BE
MORE LIMITED.

WEDNESDAY...ANOTHER QUITE WINDY DAY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS. RELATIVELY MILD PER 850 MB AND 700 TEMPERATURES AND
DOWNSLOPE WARMING. ISOLATED TO SCATTERED SNOWS ACROSS OUR NORTHERN
COUNTIES FROM DOUGLAS TO LUSK TO CHADRON.

THANKSGIVING...THE MODELS ARE NOW SHOWING WEST NORTHWEST FLOW ALOFT
WITH OUR COUNTIES IN THE WARM SECTOR...ALONG WITH DOWNSLOPE WEST
WINDS. WILL BLEND WITH OUR NEIGHBORING OFFICE AND KEEP HIGH
TEMPERATURES DOWN...THOUGH LATER SHIFTS WILL NEED TO BETTER ASSESS
THE SITUATION.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1109 AM MST FRI NOV 21 2014

MAIN AVIATION CONCERNS WILL FOCUS ON WINDS LATER TONIGHT AND INTO
TOMORROW. WILL ALSO SEE SNOW DEVELOP OVER THE MOUNTAINS TOMORROW.
STRONG WINDS WITH FREQUENT GUSTS TO 50 KTS WILL DEVELOP IN THE
ARLINGTON AREA AND INTO THE BORDEAUX AREA LATE TONIGHT. THESE
STRONG WEST TO SOUTHWEST WINDS WILL THEN SPREAD INTO THE SOUTHERN
AND NORTHERN LARAMIE RANGES TOWARD SUNRISE SATURDAY. GUSTY WINDS
WILL ALSO SPREAD INTO LOWER ELEVATIONS AND INTO THE PLAINS OF
SOUTHEAST WYOMING SATURDAY AFTERNOON WITH GUSTS OF 30 TO 40 KTS
BEING COMMON. WINDS WILL NOT BE AS STRONG INTO THE NEBRASKA
PANHANDLE BUT STILL BREEZY TO WINDY SATURDAY AFTERNOON.

MOUNTAINS WILL BE OBSCURED DUE TO FALLING AND BLOWING SNOW
SATURDAY AFTERNOON...ESPECIALLY INTO THE SNOWY AND SIERRA MADRE
RANGES WHERE A WINTER STORM WATCH IS CURRENTLY IN EFFECT. PERIODS
OF SNOW WILL CONTINUE INTO MONDAY ACROSS THESE MOUNTAINS.


&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING
     FOR WYZ104-105-116-117.

     HIGH WIND WATCH FROM LATE TONIGHT THROUGH SATURDAY EVENING FOR
     WYZ106-110.

NE...NONE.

&&

$$

UPDATE...CLH
SHORT TERM...RJM
LONG TERM...SAR
AVIATION...SML
FIRE WEATHER...RJM



000
FXUS63 KUNR 211804
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1104 AM MST FRI NOV 21 2014

.SHORT TERM...TODAY THROUGH SATURDAY NIGHT
ISSUED AT 252 AM MST FRI NOV 21 2014

WATER VAPOR SHOWS DEEP TROF SHIFTING EAST OF THE GREAT LAKES WITH
SHORT WAVE RIDGE PUSHING INTO THE WRN DAKOTAS. NEXT UPSTREAM TROF
IS NOTED OFFSHORE THE PAC NW. AT THE SFC...LEE TROF HAS ADVANCED
INTO ERN MT/ERN WY.

TODAY...THERMAL RIDGE PASSING OVERHEAD ALONG WITH SFC TROF PUSHING
THROUGH WILL SCOUR OUT THE REMAINING ARCTIC AIR AND ALLOW TEMPS TO
RISE WELL INTO THE 40S MOST LOCATIONS. WARMEST TEMPS WILL LIKELY
BE ALONG THE ERN SLOPES OF THE BLKHLS WITH A WESTERLY DOWNSLOPE
COMPONENT AIDING IN THE WARMING.

SATURDAY...SW FLOW ALOFT RETURNS AS NEXT TROF ADVANCES QUICKLY
THROUGH THE PAC NW INTO THE NRN ROCKIES. THIS WILL ALLOW EVEN
WARMER AIR TO SPILL INTO OUR REGION WITH SOME PLACES EAST/SOUTH OF
THE BLKHLS REACHING INTO THE 50S. PCPN CHANCES WILL INCREASE
SATURDAY NIGHT AS UPPER TROF WORKS INTO THE NRN PLAINS. BEST LIFT
SHOULD REMAIN NORTH OF THE CWFA...BUT THERE IS STILL A GOOD CHANCE
OF POST FRONTAL RAIN CHANGING TO SNOW ACRS NERN WY...THE
BLKHLS...AND NWRN SD.

&&

.LONG TERM...SUNDAY THROUGH THURSDAY
ISSUED AT 252 AM MST FRI NOV 21 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. TIGHT PRESSURE GRADIENT ASSOCIATED WITH COLD AIR
ADVECTION ON THE BACKSIDE OF A LOW PRESSURE PUSHING INTO THE UPPER
MIDWEST WILL BRING VERY WINDY CONDITIONS TO MUCH OF THE WRN SD
PLAINS ON SUNDAY. UPSLOPE ENHANCED SHSN WILL MAINLY AFFECT THE
NRN BLKHLS SUNDAY. WINDS WILL REMAIN BREEZY ON MONDAY AS STRONG
PRESSURE RISES MOVE THROUGH. ON WEDNESDAY...THE NEXT UPPER TROUGH
WILL BEGIN SWINGING THROUGH THE NORTHERN PLAINS STATES...BRINGING
IN ANOTHER SHOT OF COLD AIR AND MORE WIDESPREAD CHANCES FOR SNOW.
MODELS DIVERGE WITH THE ENDING OF SNOW WED NIGHT/THANKSGIVING WITH
THE ECMWF BEING THE FASTEST. WILL END SNOW BY THANKSGIVING MORNING
FOR NOW.

&&

.AVIATION...FOR THE 18Z TAFS THROUGH 18Z SATURDAY
ISSUED AT 1104 AM MST FRI NOV 21 2014

VFR CONDITIONS ARE EXPECTED THROUGH TONIGHT. BREEZY WEST
WINDS CAN BE EXPECTED ACROSS NORTHWEST SD THIS AFTERNOON...WITH
BREEZY SOUTHWESTERLY WINDS DEVELOPING ACROSS NORTHEAST WY TONIGHT.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...JOHNSON
LONG TERM...13
AVIATION...26






000
FXUS63 KUNR 211804
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1104 AM MST FRI NOV 21 2014

.SHORT TERM...TODAY THROUGH SATURDAY NIGHT
ISSUED AT 252 AM MST FRI NOV 21 2014

WATER VAPOR SHOWS DEEP TROF SHIFTING EAST OF THE GREAT LAKES WITH
SHORT WAVE RIDGE PUSHING INTO THE WRN DAKOTAS. NEXT UPSTREAM TROF
IS NOTED OFFSHORE THE PAC NW. AT THE SFC...LEE TROF HAS ADVANCED
INTO ERN MT/ERN WY.

TODAY...THERMAL RIDGE PASSING OVERHEAD ALONG WITH SFC TROF PUSHING
THROUGH WILL SCOUR OUT THE REMAINING ARCTIC AIR AND ALLOW TEMPS TO
RISE WELL INTO THE 40S MOST LOCATIONS. WARMEST TEMPS WILL LIKELY
BE ALONG THE ERN SLOPES OF THE BLKHLS WITH A WESTERLY DOWNSLOPE
COMPONENT AIDING IN THE WARMING.

SATURDAY...SW FLOW ALOFT RETURNS AS NEXT TROF ADVANCES QUICKLY
THROUGH THE PAC NW INTO THE NRN ROCKIES. THIS WILL ALLOW EVEN
WARMER AIR TO SPILL INTO OUR REGION WITH SOME PLACES EAST/SOUTH OF
THE BLKHLS REACHING INTO THE 50S. PCPN CHANCES WILL INCREASE
SATURDAY NIGHT AS UPPER TROF WORKS INTO THE NRN PLAINS. BEST LIFT
SHOULD REMAIN NORTH OF THE CWFA...BUT THERE IS STILL A GOOD CHANCE
OF POST FRONTAL RAIN CHANGING TO SNOW ACRS NERN WY...THE
BLKHLS...AND NWRN SD.

&&

.LONG TERM...SUNDAY THROUGH THURSDAY
ISSUED AT 252 AM MST FRI NOV 21 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. TIGHT PRESSURE GRADIENT ASSOCIATED WITH COLD AIR
ADVECTION ON THE BACKSIDE OF A LOW PRESSURE PUSHING INTO THE UPPER
MIDWEST WILL BRING VERY WINDY CONDITIONS TO MUCH OF THE WRN SD
PLAINS ON SUNDAY. UPSLOPE ENHANCED SHSN WILL MAINLY AFFECT THE
NRN BLKHLS SUNDAY. WINDS WILL REMAIN BREEZY ON MONDAY AS STRONG
PRESSURE RISES MOVE THROUGH. ON WEDNESDAY...THE NEXT UPPER TROUGH
WILL BEGIN SWINGING THROUGH THE NORTHERN PLAINS STATES...BRINGING
IN ANOTHER SHOT OF COLD AIR AND MORE WIDESPREAD CHANCES FOR SNOW.
MODELS DIVERGE WITH THE ENDING OF SNOW WED NIGHT/THANKSGIVING WITH
THE ECMWF BEING THE FASTEST. WILL END SNOW BY THANKSGIVING MORNING
FOR NOW.

&&

.AVIATION...FOR THE 18Z TAFS THROUGH 18Z SATURDAY
ISSUED AT 1104 AM MST FRI NOV 21 2014

VFR CONDITIONS ARE EXPECTED THROUGH TONIGHT. BREEZY WEST
WINDS CAN BE EXPECTED ACROSS NORTHWEST SD THIS AFTERNOON...WITH
BREEZY SOUTHWESTERLY WINDS DEVELOPING ACROSS NORTHEAST WY TONIGHT.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...JOHNSON
LONG TERM...13
AVIATION...26






000
FXUS63 KUNR 211804
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1104 AM MST FRI NOV 21 2014

.SHORT TERM...TODAY THROUGH SATURDAY NIGHT
ISSUED AT 252 AM MST FRI NOV 21 2014

WATER VAPOR SHOWS DEEP TROF SHIFTING EAST OF THE GREAT LAKES WITH
SHORT WAVE RIDGE PUSHING INTO THE WRN DAKOTAS. NEXT UPSTREAM TROF
IS NOTED OFFSHORE THE PAC NW. AT THE SFC...LEE TROF HAS ADVANCED
INTO ERN MT/ERN WY.

TODAY...THERMAL RIDGE PASSING OVERHEAD ALONG WITH SFC TROF PUSHING
THROUGH WILL SCOUR OUT THE REMAINING ARCTIC AIR AND ALLOW TEMPS TO
RISE WELL INTO THE 40S MOST LOCATIONS. WARMEST TEMPS WILL LIKELY
BE ALONG THE ERN SLOPES OF THE BLKHLS WITH A WESTERLY DOWNSLOPE
COMPONENT AIDING IN THE WARMING.

SATURDAY...SW FLOW ALOFT RETURNS AS NEXT TROF ADVANCES QUICKLY
THROUGH THE PAC NW INTO THE NRN ROCKIES. THIS WILL ALLOW EVEN
WARMER AIR TO SPILL INTO OUR REGION WITH SOME PLACES EAST/SOUTH OF
THE BLKHLS REACHING INTO THE 50S. PCPN CHANCES WILL INCREASE
SATURDAY NIGHT AS UPPER TROF WORKS INTO THE NRN PLAINS. BEST LIFT
SHOULD REMAIN NORTH OF THE CWFA...BUT THERE IS STILL A GOOD CHANCE
OF POST FRONTAL RAIN CHANGING TO SNOW ACRS NERN WY...THE
BLKHLS...AND NWRN SD.

&&

.LONG TERM...SUNDAY THROUGH THURSDAY
ISSUED AT 252 AM MST FRI NOV 21 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. TIGHT PRESSURE GRADIENT ASSOCIATED WITH COLD AIR
ADVECTION ON THE BACKSIDE OF A LOW PRESSURE PUSHING INTO THE UPPER
MIDWEST WILL BRING VERY WINDY CONDITIONS TO MUCH OF THE WRN SD
PLAINS ON SUNDAY. UPSLOPE ENHANCED SHSN WILL MAINLY AFFECT THE
NRN BLKHLS SUNDAY. WINDS WILL REMAIN BREEZY ON MONDAY AS STRONG
PRESSURE RISES MOVE THROUGH. ON WEDNESDAY...THE NEXT UPPER TROUGH
WILL BEGIN SWINGING THROUGH THE NORTHERN PLAINS STATES...BRINGING
IN ANOTHER SHOT OF COLD AIR AND MORE WIDESPREAD CHANCES FOR SNOW.
MODELS DIVERGE WITH THE ENDING OF SNOW WED NIGHT/THANKSGIVING WITH
THE ECMWF BEING THE FASTEST. WILL END SNOW BY THANKSGIVING MORNING
FOR NOW.

&&

.AVIATION...FOR THE 18Z TAFS THROUGH 18Z SATURDAY
ISSUED AT 1104 AM MST FRI NOV 21 2014

VFR CONDITIONS ARE EXPECTED THROUGH TONIGHT. BREEZY WEST
WINDS CAN BE EXPECTED ACROSS NORTHWEST SD THIS AFTERNOON...WITH
BREEZY SOUTHWESTERLY WINDS DEVELOPING ACROSS NORTHEAST WY TONIGHT.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...JOHNSON
LONG TERM...13
AVIATION...26






000
FXUS63 KUNR 211804
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1104 AM MST FRI NOV 21 2014

.SHORT TERM...TODAY THROUGH SATURDAY NIGHT
ISSUED AT 252 AM MST FRI NOV 21 2014

WATER VAPOR SHOWS DEEP TROF SHIFTING EAST OF THE GREAT LAKES WITH
SHORT WAVE RIDGE PUSHING INTO THE WRN DAKOTAS. NEXT UPSTREAM TROF
IS NOTED OFFSHORE THE PAC NW. AT THE SFC...LEE TROF HAS ADVANCED
INTO ERN MT/ERN WY.

TODAY...THERMAL RIDGE PASSING OVERHEAD ALONG WITH SFC TROF PUSHING
THROUGH WILL SCOUR OUT THE REMAINING ARCTIC AIR AND ALLOW TEMPS TO
RISE WELL INTO THE 40S MOST LOCATIONS. WARMEST TEMPS WILL LIKELY
BE ALONG THE ERN SLOPES OF THE BLKHLS WITH A WESTERLY DOWNSLOPE
COMPONENT AIDING IN THE WARMING.

SATURDAY...SW FLOW ALOFT RETURNS AS NEXT TROF ADVANCES QUICKLY
THROUGH THE PAC NW INTO THE NRN ROCKIES. THIS WILL ALLOW EVEN
WARMER AIR TO SPILL INTO OUR REGION WITH SOME PLACES EAST/SOUTH OF
THE BLKHLS REACHING INTO THE 50S. PCPN CHANCES WILL INCREASE
SATURDAY NIGHT AS UPPER TROF WORKS INTO THE NRN PLAINS. BEST LIFT
SHOULD REMAIN NORTH OF THE CWFA...BUT THERE IS STILL A GOOD CHANCE
OF POST FRONTAL RAIN CHANGING TO SNOW ACRS NERN WY...THE
BLKHLS...AND NWRN SD.

&&

.LONG TERM...SUNDAY THROUGH THURSDAY
ISSUED AT 252 AM MST FRI NOV 21 2014

AN ACTIVE PATTERN ASSOCIATED WITH DEEP CYCLONIC FLOW
ALOFT WILL CONTINUE ACROSS THE NORTH CENTRAL CONUS THROUGH EARLY
NEXT WEEK. TIGHT PRESSURE GRADIENT ASSOCIATED WITH COLD AIR
ADVECTION ON THE BACKSIDE OF A LOW PRESSURE PUSHING INTO THE UPPER
MIDWEST WILL BRING VERY WINDY CONDITIONS TO MUCH OF THE WRN SD
PLAINS ON SUNDAY. UPSLOPE ENHANCED SHSN WILL MAINLY AFFECT THE
NRN BLKHLS SUNDAY. WINDS WILL REMAIN BREEZY ON MONDAY AS STRONG
PRESSURE RISES MOVE THROUGH. ON WEDNESDAY...THE NEXT UPPER TROUGH
WILL BEGIN SWINGING THROUGH THE NORTHERN PLAINS STATES...BRINGING
IN ANOTHER SHOT OF COLD AIR AND MORE WIDESPREAD CHANCES FOR SNOW.
MODELS DIVERGE WITH THE ENDING OF SNOW WED NIGHT/THANKSGIVING WITH
THE ECMWF BEING THE FASTEST. WILL END SNOW BY THANKSGIVING MORNING
FOR NOW.

&&

.AVIATION...FOR THE 18Z TAFS THROUGH 18Z SATURDAY
ISSUED AT 1104 AM MST FRI NOV 21 2014

VFR CONDITIONS ARE EXPECTED THROUGH TONIGHT. BREEZY WEST
WINDS CAN BE EXPECTED ACROSS NORTHWEST SD THIS AFTERNOON...WITH
BREEZY SOUTHWESTERLY WINDS DEVELOPING ACROSS NORTHEAST WY TONIGHT.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...JOHNSON
LONG TERM...13
AVIATION...26






000
FXUS65 KRIW 211736
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1036 AM MST FRI NOV 21 2014

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT

WV IMAGERY SHOWING FLATTENING EXITING RIDGE ACROSS ROCKY MNT
STATES WITH WEAK SW TROF MOVING THRU THE RIDGE ALIGNED FROM NCNTRL
MT...S THRU CNTRL WY AND INTO ERN NM. DRYING CURRENTLY TAKING
PLACE ACROSS THE WRN ZONES. TRAILING BEHIND AND FURTHER
UPSTREAM...A RIDGE OVR TROF SET-UP EXISTS WITH STRONGER
DISTURBANCE LYING IN WAIT DOWN THE WEST COAST WITH RIDGE N AND
THRU BC. SFC HAS SIMILAR PATTERN TO THAT OF THE LAST COUPLE OF
DAYS...WITH STATIONARY LOW STRETCHING FROM SERN WY...THRU THE NE
CORNER AND UP INTO CNTRL MT.

TODAY...OPENING/SPLITTING TROF MOWING DOWN THE RIDGE CONTINUES TO
MOVE ACROSS THE FA TODAY. ONLY FLURRIES HAVE PRESENTED THEMSELVES
EARLIER THIS EVENING IN THE MOUNTAINS. NOT MUCH WILL HAPPEN WITH
THIS WEAK SYSTEM OTHER OTHER THAN PERHAPS SOME VERY LIGHT SNOW OR
FLURRIES LATER THIS AFTERNOON AS A SLIGHT INCREASE IN MOISTURE FROM
THE WEST BEGINS TO MAKE ITS WAY INTO THE WRN HIGH MOUNTAINS.

TONIGHT...A NEW AND BETTER INFLUX OF MOISTURE BEGINS TO INFILTRATE
THE WRN REGION...LEADING TO A GOOD WINTER WEATHER SCENARIO BY SAT
MORNING...WITH CONVECTIVE ELEMENTS PLAYING INTO THE SET-UP BY
MID-DAY SATURDAY. QPF VALUES CONTINUE ON THE RISE THRU THE LAST
SEVERAL DAY WITH MDL RANGES NOW BETWEEN .6 AND AND JUST OVR AN INCH
PLUS IN LIQUID BETWEEN 06 SAT AND 12Z SUN BOTH IN THE MOUNTAINS AND
VALLEYS WITH HIGHER AMOUNTS ON THE WINDWARD SLOPES. THIS NOW GIVES
GENERALIZED SNOW AMOUNTS RANGING FROM 6 TO 10 INCHES IN THE VALLEYS
AND 10 TO 18 INCHES WITH SOME AREAS UP TO 20 INCHES IN THE
MOUNTAINS...ESPECIALLY THE TETONS AND WESTERN WIND RIVER MOUNTAINS.
WINTER STORM WATCHES HAVE BEEN HOISTED FOR MUCH OF THESE AREAS. THIS
FCST WILL ALSO ADD ZONES 2 14 AND 15 TO THE WATCH LIST...FOR SNOW
AND BLOWING SNOW...WITH NEAR BLIZZARD-LIKE CONDITIONS POSSIBLE IN
THESE LATEST MOUNTAIN LOCATIONS. THIS IS PARTIALLY DUE TO INCREASED
MOISTURE DEPTH AND PARTLY DUE TO A SLIGHTLY BETTER JET POSITION. AS
THE TROF/DISTURBANCE AXIS MOVES THRU OVERNIGHT SAT INTO SUN
MORNING...SNOW WILL TAPER FOR A BIT AS AVAILABLE MOISTURE WANES.
HOWEVER...THIS WILL QUICKLY BE FOLLOWED BY TRANSITION BACK TO NW
FLOW WITH A RENEWED MOISTURE PLUME DUE TO ARRIVE LATER ON SUNDAY.
BOTH THIS MOISTURE AND INCREASED UPR LVL DYNAMICS KICKED OFF BY AN
EVER STRENGTHENING JET OVERHEAD WILL RAPIDLY INCREASE PRECIP/SNOW
POTENTIAL BY SUNDAY NIGHT. THE WAY IT LOOKS NOW...NEW OR EXTENDED
WINTER WX HIGHLIGHTS WILL LIKELY BE NEEDED AT THIS TIME ACROSS THE
WEST. FINALLY...WINTER ADVISORY CONDITIONS ARE LOOKING GOOD FOR ZONE
16 WITH PERHAPS A QUICK 2 TO 4 INCHES OF SNOW ADDING TO INCREASED
WINDS LATER ON SATURDAY.

THE OTHER WARNING HIGHLIGHT PHENOM HINTED AT ABOVE WILL BE WARNING
CLASS WINDS OUT OF THE W TO SW WHICH WILL PICK-UP ACROSS THE
NORTHERN AND CENTRAL MOUNTAIN REGION ALONG WITH THE CODY FOOTHILLS.
THESE MOUNTAIN AREAS WILL BE ADDED INTO  THE STORM WARNING...WHILE
THE CODY FOOTHILLS AND CASPER MOUNTAIN WILL BE ADDED TO THE HIGH
WIND WATCH CURRENTLY OUT THAT INCLUDES THE REGION BETWEEN SOUTH PASS
TO THE CASPER AREA. MOUNTAIN WAVE PRODUCTION LOOKS LIKE A SURE THING
AT THIS POINT...ESPECIALLY OVER AND EAST OF THE ABSAROKA AND WIND
RIVER MOUNTAINS...WITH GOOD STRONG P AND T GRADIENTS E OF THE
DIVIDE. ADDITIONALLY...LEE TROF E OF THE BIGHORNS TO MEDICINE BOW
MNTS WILL FURTHER INCREASE P GRAD LOCALLY...ALLOWING FOR STRONG MID
LVL FLOW TO COMBINE WITH A TIGHT P GRAD AND DECENT INSTABILITY FOR
THIS TIME OF YEAR TO GET WINDS REALLY HOWLING OVR THE CASPER
MOUNTAIN REGION.

.LONG TERM...MONDAY THROUGH FRIDAY

A STRONG...MOIST NORTHWEST FLOW WILL REMAIN IN PLACE MONDAY AND
TUESDAY. THIS WILL RESULT IN THE CONTINUATION OF AT LEAST LIGHT SNOW
OVER THE NORTHWEST/NORTHERN MOUNTAINS THROUGH TUESDAY NIGHT. AN ALBERTA
CLIPPER SLIDING SOUTHEAST INTO THE NORTHERN PLAINS TUESDAY SHOULD
RESULT IN BETTER AREAL COVERAGE AND INTENSITY OF SNOW TUESDAY/TUESDAY
EVENING...WITH MOST OF THE IMPACT OVER THE NORTHWEST AND NORTH...INCLUDING
THE LOWER ELEVATIONS. ALSO...THIS ALBERTA CLIPPER WILL TIGHTEN UP
THE SURFACE PRESSURE GRADIENT OVER THE FORECAST AREA RESULTING IN
WINDY TO POSSIBLY HIGH WIND ACROSS PORTIONS OF THE AREA.

MEDIUM RANGE MODELS CONTINUE TO HAVE AN ARRAY OF SOLUTIONS FOR
WEDNESDAY INTO THANKSGIVING. THE ECMWF WHICH HAD BEEN VERY
CONSISTENT IN BRINGING A TROUGH...AND ASSOCIATED CANADIAN COLD FRONT
OF VARYING INTENSITIES SOUTH OUT OF CANADA...IS NOW SHOWING A MILD
AND DRY PATTERN AS THE EASTERN PACIFIC UPPER RIDGE SHIFTS EAST INTO
THE WEST/ROCKIES. THIS SOLUTION IS SIMILAR TO WHAT THE GFS WAS
ADVERTISING A FEW DAYS AGO. THE 00Z GFS SHOWS A SIGNIFICANT
SHORTWAVE TROUGH IN THE NORTHWEST FLOW...AND THE ASSOCIATED
CANADIAN COLD FRONT IMPACTING THE AREA WEDNESDAY NIGHT AND
THURSDAY. LEANING MORE TOWARDS THE 00Z GFS AND PREVIOUS RUNS OF
THE ECMWF FOR THIS FORECAST. ALTHOUGH HAVE TRENDED TEMPERATURES A
BIT WARMER WEDNESDAY/THURSDAY...BUT ESPECIALLY ON WEDNESDAY WHICH
SHOULD BE AHEAD OF A CANADIAN COLD FRONT...REGARDLESS OF SOLUTION USED.
HAVE BROAD BRUSHED CHANCE MOUNTAIN/SLIGHT VALLEY POPS WEDNESDAY
AND THURSDAY...WITH A SLIGHT EMPHASIS ALONG AND EAST OF THE DIVIDE.

&&

.AVIATION.../18Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES

VFR CONDITIONS EXPECTED ACROSS THE AREA THROUGH THE EVENING
HOURS...THOUGH PERIODS OF BREEZY WIND WILL BE FOUND AT KCPR AND
AREAS SOUTHWEST OF THE TERMINAL. THE APPROACHING WINTER SYSTEM
WILL CAUSE WIND SHEAR OVER MANY OF THE TERMINALS AFTER 08Z THIS
EVENING. LLWS HAS BEEN INCLUDED AT THE MAJORITY OF
TERMINALS...EXCEPT AT KCPR. UPPER LEVEL WIND WILL STILL BE STRONG
AT KCPR AS WELL...BUT WITH ALREADY STRONG SURFACE WIND
PRESENT...THE CHANGE BETWEEN SPEEDS AT THE LEVELS IS NOT AS
SIGNIFICANT.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES

A FAIRLY MESSY AVIATION PERIOD AHEAD FOR AREAS WEST OF THE
CONTINENTAL DIVIDE. SNOWFALL ASSOCIATED WITH THE APPROACHING
WINTER SYSTEM WILL BEING TO IMPACT THE WESTERN MOUNTAINS AND
VALLEYS AFTER 03Z THIS EVENING...WITH PREVAILING -SN ANTICIPATED
AFTER 09Z AT KJAC. SNOWFALL WILL INTENSIFY AND INCREASE IN
COVERAGE THROUGH THE OVERNIGHT HOURS...WITH MOST TERMINALS SEEING
PREVAILING SNOW BY 14Z SATURDAY. ADDITIONALLY...STRONG WIND SHEAR
WILL BE PRESENT AT THE TERMINALS...ESPECIALLY AFTER 09Z THIS
EVENING. EXPECT INCREASED TURBULENCE OVER THE WESTERN AVIATION
PASSES...AND ALSO MOUNTAIN OBSCURATION WITH LOW CLOUDS AND ONGOING
SNOWFALL.

&&

.FIRE WEATHER...

FIRE DANGER LOW AND REMAINING LOW THROUGH THE WEEKEND AS EXISTING SNOW
COVER OR HIGHER MINIMUM RH VALUES KEEP FIRE WEATHER PARAMETERS
WELL ABOVE CRITICAL LEVELS. ADDITIONALLY...MOISTURE WILL BEGIN TO INCREASE
ACROSS THE WEST TODAY WITH LIGHT WIDELY SCATTERED AREAS OF SNOW
BECOMING POSSIBLE OVER THE WESTERN CENTRAL AND NORTHERN MOUNTAIN FORECAST
ZONES TONIGHT...INCREASING IN COVERAGE AND INTENSITY AFTER
MIDNIGHT. HOWEVER...INCREASING STRONG WEST TO SOUTHWEST WIND WILL
ALSO ACCOMPANY THIS WINTER WEATHER STORM SYSTEM...WITH HIGH WINDS
EXPECTED ACROSS THE NORTHERN AND CENTRAL MOUNTAINS AND ALSO FROM
SOUTH PASS EASTWARD THROUGH MOST OF NATRONA COUNTY BETWEEN SATURDAY
MORNING AND AFTERNOON...LASTING INTO THE EVENING.


&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING
WYZ003-019-020-022.

WINTER STORM WATCH FROM LATE TONIGHT THROUGH LATE SATURDAY NIGHT
WYZ001-002-012>015-023>025.

&&

$$

SHORT TERM...BRAUN
LONG TERM...WM
AVIATION...BRANHAM
FIRE WEATHER...BRAUN






000
FXUS65 KRIW 211736
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1036 AM MST FRI NOV 21 2014

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT

WV IMAGERY SHOWING FLATTENING EXITING RIDGE ACROSS ROCKY MNT
STATES WITH WEAK SW TROF MOVING THRU THE RIDGE ALIGNED FROM NCNTRL
MT...S THRU CNTRL WY AND INTO ERN NM. DRYING CURRENTLY TAKING
PLACE ACROSS THE WRN ZONES. TRAILING BEHIND AND FURTHER
UPSTREAM...A RIDGE OVR TROF SET-UP EXISTS WITH STRONGER
DISTURBANCE LYING IN WAIT DOWN THE WEST COAST WITH RIDGE N AND
THRU BC. SFC HAS SIMILAR PATTERN TO THAT OF THE LAST COUPLE OF
DAYS...WITH STATIONARY LOW STRETCHING FROM SERN WY...THRU THE NE
CORNER AND UP INTO CNTRL MT.

TODAY...OPENING/SPLITTING TROF MOWING DOWN THE RIDGE CONTINUES TO
MOVE ACROSS THE FA TODAY. ONLY FLURRIES HAVE PRESENTED THEMSELVES
EARLIER THIS EVENING IN THE MOUNTAINS. NOT MUCH WILL HAPPEN WITH
THIS WEAK SYSTEM OTHER OTHER THAN PERHAPS SOME VERY LIGHT SNOW OR
FLURRIES LATER THIS AFTERNOON AS A SLIGHT INCREASE IN MOISTURE FROM
THE WEST BEGINS TO MAKE ITS WAY INTO THE WRN HIGH MOUNTAINS.

TONIGHT...A NEW AND BETTER INFLUX OF MOISTURE BEGINS TO INFILTRATE
THE WRN REGION...LEADING TO A GOOD WINTER WEATHER SCENARIO BY SAT
MORNING...WITH CONVECTIVE ELEMENTS PLAYING INTO THE SET-UP BY
MID-DAY SATURDAY. QPF VALUES CONTINUE ON THE RISE THRU THE LAST
SEVERAL DAY WITH MDL RANGES NOW BETWEEN .6 AND AND JUST OVR AN INCH
PLUS IN LIQUID BETWEEN 06 SAT AND 12Z SUN BOTH IN THE MOUNTAINS AND
VALLEYS WITH HIGHER AMOUNTS ON THE WINDWARD SLOPES. THIS NOW GIVES
GENERALIZED SNOW AMOUNTS RANGING FROM 6 TO 10 INCHES IN THE VALLEYS
AND 10 TO 18 INCHES WITH SOME AREAS UP TO 20 INCHES IN THE
MOUNTAINS...ESPECIALLY THE TETONS AND WESTERN WIND RIVER MOUNTAINS.
WINTER STORM WATCHES HAVE BEEN HOISTED FOR MUCH OF THESE AREAS. THIS
FCST WILL ALSO ADD ZONES 2 14 AND 15 TO THE WATCH LIST...FOR SNOW
AND BLOWING SNOW...WITH NEAR BLIZZARD-LIKE CONDITIONS POSSIBLE IN
THESE LATEST MOUNTAIN LOCATIONS. THIS IS PARTIALLY DUE TO INCREASED
MOISTURE DEPTH AND PARTLY DUE TO A SLIGHTLY BETTER JET POSITION. AS
THE TROF/DISTURBANCE AXIS MOVES THRU OVERNIGHT SAT INTO SUN
MORNING...SNOW WILL TAPER FOR A BIT AS AVAILABLE MOISTURE WANES.
HOWEVER...THIS WILL QUICKLY BE FOLLOWED BY TRANSITION BACK TO NW
FLOW WITH A RENEWED MOISTURE PLUME DUE TO ARRIVE LATER ON SUNDAY.
BOTH THIS MOISTURE AND INCREASED UPR LVL DYNAMICS KICKED OFF BY AN
EVER STRENGTHENING JET OVERHEAD WILL RAPIDLY INCREASE PRECIP/SNOW
POTENTIAL BY SUNDAY NIGHT. THE WAY IT LOOKS NOW...NEW OR EXTENDED
WINTER WX HIGHLIGHTS WILL LIKELY BE NEEDED AT THIS TIME ACROSS THE
WEST. FINALLY...WINTER ADVISORY CONDITIONS ARE LOOKING GOOD FOR ZONE
16 WITH PERHAPS A QUICK 2 TO 4 INCHES OF SNOW ADDING TO INCREASED
WINDS LATER ON SATURDAY.

THE OTHER WARNING HIGHLIGHT PHENOM HINTED AT ABOVE WILL BE WARNING
CLASS WINDS OUT OF THE W TO SW WHICH WILL PICK-UP ACROSS THE
NORTHERN AND CENTRAL MOUNTAIN REGION ALONG WITH THE CODY FOOTHILLS.
THESE MOUNTAIN AREAS WILL BE ADDED INTO  THE STORM WARNING...WHILE
THE CODY FOOTHILLS AND CASPER MOUNTAIN WILL BE ADDED TO THE HIGH
WIND WATCH CURRENTLY OUT THAT INCLUDES THE REGION BETWEEN SOUTH PASS
TO THE CASPER AREA. MOUNTAIN WAVE PRODUCTION LOOKS LIKE A SURE THING
AT THIS POINT...ESPECIALLY OVER AND EAST OF THE ABSAROKA AND WIND
RIVER MOUNTAINS...WITH GOOD STRONG P AND T GRADIENTS E OF THE
DIVIDE. ADDITIONALLY...LEE TROF E OF THE BIGHORNS TO MEDICINE BOW
MNTS WILL FURTHER INCREASE P GRAD LOCALLY...ALLOWING FOR STRONG MID
LVL FLOW TO COMBINE WITH A TIGHT P GRAD AND DECENT INSTABILITY FOR
THIS TIME OF YEAR TO GET WINDS REALLY HOWLING OVR THE CASPER
MOUNTAIN REGION.

.LONG TERM...MONDAY THROUGH FRIDAY

A STRONG...MOIST NORTHWEST FLOW WILL REMAIN IN PLACE MONDAY AND
TUESDAY. THIS WILL RESULT IN THE CONTINUATION OF AT LEAST LIGHT SNOW
OVER THE NORTHWEST/NORTHERN MOUNTAINS THROUGH TUESDAY NIGHT. AN ALBERTA
CLIPPER SLIDING SOUTHEAST INTO THE NORTHERN PLAINS TUESDAY SHOULD
RESULT IN BETTER AREAL COVERAGE AND INTENSITY OF SNOW TUESDAY/TUESDAY
EVENING...WITH MOST OF THE IMPACT OVER THE NORTHWEST AND NORTH...INCLUDING
THE LOWER ELEVATIONS. ALSO...THIS ALBERTA CLIPPER WILL TIGHTEN UP
THE SURFACE PRESSURE GRADIENT OVER THE FORECAST AREA RESULTING IN
WINDY TO POSSIBLY HIGH WIND ACROSS PORTIONS OF THE AREA.

MEDIUM RANGE MODELS CONTINUE TO HAVE AN ARRAY OF SOLUTIONS FOR
WEDNESDAY INTO THANKSGIVING. THE ECMWF WHICH HAD BEEN VERY
CONSISTENT IN BRINGING A TROUGH...AND ASSOCIATED CANADIAN COLD FRONT
OF VARYING INTENSITIES SOUTH OUT OF CANADA...IS NOW SHOWING A MILD
AND DRY PATTERN AS THE EASTERN PACIFIC UPPER RIDGE SHIFTS EAST INTO
THE WEST/ROCKIES. THIS SOLUTION IS SIMILAR TO WHAT THE GFS WAS
ADVERTISING A FEW DAYS AGO. THE 00Z GFS SHOWS A SIGNIFICANT
SHORTWAVE TROUGH IN THE NORTHWEST FLOW...AND THE ASSOCIATED
CANADIAN COLD FRONT IMPACTING THE AREA WEDNESDAY NIGHT AND
THURSDAY. LEANING MORE TOWARDS THE 00Z GFS AND PREVIOUS RUNS OF
THE ECMWF FOR THIS FORECAST. ALTHOUGH HAVE TRENDED TEMPERATURES A
BIT WARMER WEDNESDAY/THURSDAY...BUT ESPECIALLY ON WEDNESDAY WHICH
SHOULD BE AHEAD OF A CANADIAN COLD FRONT...REGARDLESS OF SOLUTION USED.
HAVE BROAD BRUSHED CHANCE MOUNTAIN/SLIGHT VALLEY POPS WEDNESDAY
AND THURSDAY...WITH A SLIGHT EMPHASIS ALONG AND EAST OF THE DIVIDE.

&&

.AVIATION.../18Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES

VFR CONDITIONS EXPECTED ACROSS THE AREA THROUGH THE EVENING
HOURS...THOUGH PERIODS OF BREEZY WIND WILL BE FOUND AT KCPR AND
AREAS SOUTHWEST OF THE TERMINAL. THE APPROACHING WINTER SYSTEM
WILL CAUSE WIND SHEAR OVER MANY OF THE TERMINALS AFTER 08Z THIS
EVENING. LLWS HAS BEEN INCLUDED AT THE MAJORITY OF
TERMINALS...EXCEPT AT KCPR. UPPER LEVEL WIND WILL STILL BE STRONG
AT KCPR AS WELL...BUT WITH ALREADY STRONG SURFACE WIND
PRESENT...THE CHANGE BETWEEN SPEEDS AT THE LEVELS IS NOT AS
SIGNIFICANT.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES

A FAIRLY MESSY AVIATION PERIOD AHEAD FOR AREAS WEST OF THE
CONTINENTAL DIVIDE. SNOWFALL ASSOCIATED WITH THE APPROACHING
WINTER SYSTEM WILL BEING TO IMPACT THE WESTERN MOUNTAINS AND
VALLEYS AFTER 03Z THIS EVENING...WITH PREVAILING -SN ANTICIPATED
AFTER 09Z AT KJAC. SNOWFALL WILL INTENSIFY AND INCREASE IN
COVERAGE THROUGH THE OVERNIGHT HOURS...WITH MOST TERMINALS SEEING
PREVAILING SNOW BY 14Z SATURDAY. ADDITIONALLY...STRONG WIND SHEAR
WILL BE PRESENT AT THE TERMINALS...ESPECIALLY AFTER 09Z THIS
EVENING. EXPECT INCREASED TURBULENCE OVER THE WESTERN AVIATION
PASSES...AND ALSO MOUNTAIN OBSCURATION WITH LOW CLOUDS AND ONGOING
SNOWFALL.

&&

.FIRE WEATHER...

FIRE DANGER LOW AND REMAINING LOW THROUGH THE WEEKEND AS EXISTING SNOW
COVER OR HIGHER MINIMUM RH VALUES KEEP FIRE WEATHER PARAMETERS
WELL ABOVE CRITICAL LEVELS. ADDITIONALLY...MOISTURE WILL BEGIN TO INCREASE
ACROSS THE WEST TODAY WITH LIGHT WIDELY SCATTERED AREAS OF SNOW
BECOMING POSSIBLE OVER THE WESTERN CENTRAL AND NORTHERN MOUNTAIN FORECAST
ZONES TONIGHT...INCREASING IN COVERAGE AND INTENSITY AFTER
MIDNIGHT. HOWEVER...INCREASING STRONG WEST TO SOUTHWEST WIND WILL
ALSO ACCOMPANY THIS WINTER WEATHER STORM SYSTEM...WITH HIGH WINDS
EXPECTED ACROSS THE NORTHERN AND CENTRAL MOUNTAINS AND ALSO FROM
SOUTH PASS EASTWARD THROUGH MOST OF NATRONA COUNTY BETWEEN SATURDAY
MORNING AND AFTERNOON...LASTING INTO THE EVENING.


&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING
WYZ003-019-020-022.

WINTER STORM WATCH FROM LATE TONIGHT THROUGH LATE SATURDAY NIGHT
WYZ001-002-012>015-023>025.

&&

$$

SHORT TERM...BRAUN
LONG TERM...WM
AVIATION...BRANHAM
FIRE WEATHER...BRAUN





000
FXUS65 KCYS 211259
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
559 AM MST FRI NOV 21 2014

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

AN ACTIVE PATTERN IS SHAPING UP FOR THE FORECAST AREA THIS
WEEKEND...WITH STRONG WINDS AND MOUNTAIN SNOWS THE MAIN FORECAST
CHALLENGES.

TODAY WILL BE ONE LAST RELATIVELY CALM WEATHER DAY AHEAD OF THE
MAIN PACIFIC STORM SYSTEM THAT WILL SLAM INTO THE PAC NW TODAY AND
MAKE A SOUTHEASTWARD TREK ACROSS THE ROCKIES THROUGH SUNDAY.
MILD...BREEZY AND DRY CONDITIONS WILL OCCUR TODAY IN THE WAKE OF A
WEAK SHORTWAVE TROUGH MOVING OVERHEAD THIS MORNING. FAIRLY STRONG
PRESSURE FALLS OF 4-8 MB/6 HR ARE PROGGED AHEAD OF THE PACIFIC
STORM SYSTEM TONIGHT...WHICH WILL RAPIDLY STRENGTHEN THE SFC
PRESSURE GRADIENT ACROSS SOUTHEAST WYOMING. THE CAG-CPR GRADIENT
LOOKS TO REACH THE MID 60 DAM READINGS BY SUNRISE...AND PEAK TO
MID 80 DAM VALUES BY MIDDAY SATURDAY. THE LLVL INVERSION LOOKS TO
RAPIDLY WEAKEN AND LIFT TO MOUNTAIN TOP LEVEL EARLY SATURDAY
MORNING AS WELL...SO FEEL CONFIDENT THAT THE HIGH WIND EVENT
WILL OCCUR FOR PORTIONS OF SOUTHEAST WYOMING. ISSUED A HIGH WIND
WATCH...STARTING FIRST IN THE ARLINGTON AND BORDEAUX ZONES BEFORE
SUNRISE WHICH ARE MOST SENSITIVE TO RAPID STRENGTHENING OF THE
GRADIENT AND DEVELOPMENT OF MOUNTAIN WAVE ACTIVITY...THEN
EXPANDING TO NORTHERN CARBON AND ALBANY COUNTIES AND THE SOUTHERN
LARAMIE RANGE. LOOKING AT THE POTENTIAL FOR 60 TO 70 MPH GUSTS FOR
THESE AREAS THROUGH THE DAY...WITH PERHAPS SLIGHTLY STRONGER GUSTS
IN THE MORE FAVORED GAP LOCATIONS OF ARLINGTON AND BORDEAUX.
THERE IS POTENTIAL FOR THE NEED TO EXPAND THIS HIGHLIGHT TO THE
NORTHERN LARAMIE RANGE AND WESTERN CONVERSE COUNTY AS WELL...AS
GUIDANCE IS SHOWING RATHER STRONG H7 WINDS IN EXCESS OF 65 KTS
OVER THE NORTHERN LARAMIES. CONFIDENCE IS A BIT LOWER IN THIS
SOLUTION...SO WILL HOLD OFF FOR NOW. THE PACIFIC FRONT WILL MOVE
WEST - EAST ACROSS THE FORECAST AREA AROUND SUNSET ON
SATURDAY...WITH STRONG BORA WINDS CONTINUING FOR A FEW MORE HOURS
BEFORE DIMINISHING OVERNIGHT. COULD SEE GUSTY NORTHWEST WINDS
EXPAND TO THE WYO/NEB PLAINS ON SUNDAY AFTERNOON...AND WILL NEED
TO MONITOR FOR FUTURE HIGHLIGHTS FOR THESE AREA OVER THE COMING
DAY. TEMPERATURES ON SATURDAY WILL BE QUITE MILD OVERALL IN THE
MID 40S TO UPPER 50S FROM WEST TO EAST WITH WAA AND DOWNSLOPE
WINDS IN PLACE...AND WILL COOL FOR SUNDAY BEHIND THE FRONT.

ALONG WITH THE STRONG WINDS...MODERATE TO HEAVY SNOW IS EXPECTED TO
DEVELOP IN THE MOUNTAINS OF SOUTHEAST WYOMING AS THE SYSTEM MOVES
THROUGH SATURDAY AFTERNOON THROUGH SUNDAY. LFQ JET DYNAMICS WILL
INCREASE SATURDAY AFTERNOON ALONG WITH MIDLEVEL PVA...PACIFIC
MOISTURE AND LLVL OROGRAPHIC EFFECTS WITH THE STRONG WINDS IN
PLACE. THE STRONGEST MIDLEVEL VORT MAX WILL TRAVERSE ACROSS THE
CWA SATURDAY NIGHT...WHILE THE JET DIVES SOUTH INTO AZ/NM. SO
EXPECT A HEAVY SNOW EVENT SATURDAY AFTERNOON AND NIGHT...WITH
ACCUMULATIONS AROUND ONE FOOT POSSIBLE IN THE SNOWY AND SIERRA
MADRES. COULD SEE A FEW INCHES AS WELL IN SURROUNDING VALLEYS.
BLOWING SNOW WILL BE A CONCERN WITH STRONG LLVL WINDS IN
PLACE...ALTHOUGH THEY WILL WEAKEN THROUGH THE NIGHT. THE MAIN JET
DYNAMICS WILL THEN REMAIN SOUTH OF OUR AREA ON SUNDAY AND MONDAY
ALTHOUGH MIDLEVEL ENERGY AND PACIFIC MOISTURE WILL CONTINUE TO
STREAM OVERHEAD THROUGH THIS TIME...SO EXPECT CONTINUED PERIODS OF
MODERATE TO HEAVY SNOW TO CONTINUE THROUGH SUNDAY AND MONDAY. WENT
AHEAD AND ISSUED A LONG DURATION WINTER STORM WATCH FOR THE
COMBINATION OF STEADY MODERATE/HEAVY SNOWFALL AND GUSTY WINDS THAT
ARE ANTICIPATED SATURDAY AFTERNOON THROUGH MONDAY FOR THE SNOWY
AND SIERRAS. THE HIGHEST SNOW TOTALS WILL BE ALONG WEST AND
NORTHWEST FACING SLOPES. FURTHER EAST...DOWNSLOPE WARMING AND
DRYING EFFECTS WILL SEVERELY LIMIT PRECIP CHANCES...ALTHOUGH CANT
RULE OUT A FEW SHOWERS IN THE LARAMIE RANGE AND EAST CENTRAL
WYOMING ESPECIALLY WITH THE MAIN PACIFIC FRONT SATURDAY NIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

SUNDAY NIGHT/MONDAY...MOIST NORTHWEST FLOW ALOFT WILL PRODUCE
SCATTERED TO NUMEROUS SNOW SHOWERS OVER THE SNOWY AND SIERRA MADRE
RANGES...MAINLY DRY ELSEWHERE. WINDY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS AND UNIDIRECTIONAL NORTHWEST WINDS.

TUESDAY...NORTHWEST FLOW ALOFT EVEN STRONGER...AND BASED ON
PROJECTED SURFACE THROUGH 700 MB HEIGHTS...SOME AREAS WILL LIKELY
SEE HIGH WIND CRITERIA. SLIGHT DECREASE IN MID LEVEL MOISTURE...THUS
SNOW COVERAGE ACROSS THE SNOWY AND SIERRA MADRE RANGES SHOULD BE
MORE LIMITED.

WEDNESDAY...ANOTHER QUITE WINDY DAY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS. RELATIVELY MILD PER 850 MB AND 700 TEMPERATURES AND
DOWNSLOPE WARMING. ISOLATED TO SCATTERED SNOWS ACROSS OUR NORTHERN
COUNTIES FROM DOUGLAS TO LUSK TO CHADRON.

THANKSGIVING...THE MODELS ARE NOW SHOWING WEST NORTHWEST FLOW ALOFT
WITH OUR COUNTIES IN THE WARM SECTOR...ALONG WITH DOWNSLOPE WEST
WINDS. WILL BLEND WITH OUR NEIGHBORING OFFICE AND KEEP HIGH
TEMPERATURES DOWN...THOUGH LATER SHIFTS WILL NEED TO BETTER ASSESS
THE SITUATION.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 559 AM MST FRI NOV 21 2014

VFR PREVAILS. INCREASING CLOUD COVER THIS
AFTERNOON...WITH SCATTERED TO BROKEN CLOUDS AT OR ABOVE 9000 FEET
AGL.

&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING
     FOR WYZ104-105-116-117.

     HIGH WIND WATCH FROM LATE TONIGHT THROUGH SATURDAY EVENING FOR
     WYZ106-110.

NE...NONE.
&&

$$

SHORT TERM...RJM
LONG TERM...SAR
AVIATION...SAR
FIRE WEATHER...RJM




000
FXUS65 KCYS 211259
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
559 AM MST FRI NOV 21 2014

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

AN ACTIVE PATTERN IS SHAPING UP FOR THE FORECAST AREA THIS
WEEKEND...WITH STRONG WINDS AND MOUNTAIN SNOWS THE MAIN FORECAST
CHALLENGES.

TODAY WILL BE ONE LAST RELATIVELY CALM WEATHER DAY AHEAD OF THE
MAIN PACIFIC STORM SYSTEM THAT WILL SLAM INTO THE PAC NW TODAY AND
MAKE A SOUTHEASTWARD TREK ACROSS THE ROCKIES THROUGH SUNDAY.
MILD...BREEZY AND DRY CONDITIONS WILL OCCUR TODAY IN THE WAKE OF A
WEAK SHORTWAVE TROUGH MOVING OVERHEAD THIS MORNING. FAIRLY STRONG
PRESSURE FALLS OF 4-8 MB/6 HR ARE PROGGED AHEAD OF THE PACIFIC
STORM SYSTEM TONIGHT...WHICH WILL RAPIDLY STRENGTHEN THE SFC
PRESSURE GRADIENT ACROSS SOUTHEAST WYOMING. THE CAG-CPR GRADIENT
LOOKS TO REACH THE MID 60 DAM READINGS BY SUNRISE...AND PEAK TO
MID 80 DAM VALUES BY MIDDAY SATURDAY. THE LLVL INVERSION LOOKS TO
RAPIDLY WEAKEN AND LIFT TO MOUNTAIN TOP LEVEL EARLY SATURDAY
MORNING AS WELL...SO FEEL CONFIDENT THAT THE HIGH WIND EVENT
WILL OCCUR FOR PORTIONS OF SOUTHEAST WYOMING. ISSUED A HIGH WIND
WATCH...STARTING FIRST IN THE ARLINGTON AND BORDEAUX ZONES BEFORE
SUNRISE WHICH ARE MOST SENSITIVE TO RAPID STRENGTHENING OF THE
GRADIENT AND DEVELOPMENT OF MOUNTAIN WAVE ACTIVITY...THEN
EXPANDING TO NORTHERN CARBON AND ALBANY COUNTIES AND THE SOUTHERN
LARAMIE RANGE. LOOKING AT THE POTENTIAL FOR 60 TO 70 MPH GUSTS FOR
THESE AREAS THROUGH THE DAY...WITH PERHAPS SLIGHTLY STRONGER GUSTS
IN THE MORE FAVORED GAP LOCATIONS OF ARLINGTON AND BORDEAUX.
THERE IS POTENTIAL FOR THE NEED TO EXPAND THIS HIGHLIGHT TO THE
NORTHERN LARAMIE RANGE AND WESTERN CONVERSE COUNTY AS WELL...AS
GUIDANCE IS SHOWING RATHER STRONG H7 WINDS IN EXCESS OF 65 KTS
OVER THE NORTHERN LARAMIES. CONFIDENCE IS A BIT LOWER IN THIS
SOLUTION...SO WILL HOLD OFF FOR NOW. THE PACIFIC FRONT WILL MOVE
WEST - EAST ACROSS THE FORECAST AREA AROUND SUNSET ON
SATURDAY...WITH STRONG BORA WINDS CONTINUING FOR A FEW MORE HOURS
BEFORE DIMINISHING OVERNIGHT. COULD SEE GUSTY NORTHWEST WINDS
EXPAND TO THE WYO/NEB PLAINS ON SUNDAY AFTERNOON...AND WILL NEED
TO MONITOR FOR FUTURE HIGHLIGHTS FOR THESE AREA OVER THE COMING
DAY. TEMPERATURES ON SATURDAY WILL BE QUITE MILD OVERALL IN THE
MID 40S TO UPPER 50S FROM WEST TO EAST WITH WAA AND DOWNSLOPE
WINDS IN PLACE...AND WILL COOL FOR SUNDAY BEHIND THE FRONT.

ALONG WITH THE STRONG WINDS...MODERATE TO HEAVY SNOW IS EXPECTED TO
DEVELOP IN THE MOUNTAINS OF SOUTHEAST WYOMING AS THE SYSTEM MOVES
THROUGH SATURDAY AFTERNOON THROUGH SUNDAY. LFQ JET DYNAMICS WILL
INCREASE SATURDAY AFTERNOON ALONG WITH MIDLEVEL PVA...PACIFIC
MOISTURE AND LLVL OROGRAPHIC EFFECTS WITH THE STRONG WINDS IN
PLACE. THE STRONGEST MIDLEVEL VORT MAX WILL TRAVERSE ACROSS THE
CWA SATURDAY NIGHT...WHILE THE JET DIVES SOUTH INTO AZ/NM. SO
EXPECT A HEAVY SNOW EVENT SATURDAY AFTERNOON AND NIGHT...WITH
ACCUMULATIONS AROUND ONE FOOT POSSIBLE IN THE SNOWY AND SIERRA
MADRES. COULD SEE A FEW INCHES AS WELL IN SURROUNDING VALLEYS.
BLOWING SNOW WILL BE A CONCERN WITH STRONG LLVL WINDS IN
PLACE...ALTHOUGH THEY WILL WEAKEN THROUGH THE NIGHT. THE MAIN JET
DYNAMICS WILL THEN REMAIN SOUTH OF OUR AREA ON SUNDAY AND MONDAY
ALTHOUGH MIDLEVEL ENERGY AND PACIFIC MOISTURE WILL CONTINUE TO
STREAM OVERHEAD THROUGH THIS TIME...SO EXPECT CONTINUED PERIODS OF
MODERATE TO HEAVY SNOW TO CONTINUE THROUGH SUNDAY AND MONDAY. WENT
AHEAD AND ISSUED A LONG DURATION WINTER STORM WATCH FOR THE
COMBINATION OF STEADY MODERATE/HEAVY SNOWFALL AND GUSTY WINDS THAT
ARE ANTICIPATED SATURDAY AFTERNOON THROUGH MONDAY FOR THE SNOWY
AND SIERRAS. THE HIGHEST SNOW TOTALS WILL BE ALONG WEST AND
NORTHWEST FACING SLOPES. FURTHER EAST...DOWNSLOPE WARMING AND
DRYING EFFECTS WILL SEVERELY LIMIT PRECIP CHANCES...ALTHOUGH CANT
RULE OUT A FEW SHOWERS IN THE LARAMIE RANGE AND EAST CENTRAL
WYOMING ESPECIALLY WITH THE MAIN PACIFIC FRONT SATURDAY NIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

SUNDAY NIGHT/MONDAY...MOIST NORTHWEST FLOW ALOFT WILL PRODUCE
SCATTERED TO NUMEROUS SNOW SHOWERS OVER THE SNOWY AND SIERRA MADRE
RANGES...MAINLY DRY ELSEWHERE. WINDY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS AND UNIDIRECTIONAL NORTHWEST WINDS.

TUESDAY...NORTHWEST FLOW ALOFT EVEN STRONGER...AND BASED ON
PROJECTED SURFACE THROUGH 700 MB HEIGHTS...SOME AREAS WILL LIKELY
SEE HIGH WIND CRITERIA. SLIGHT DECREASE IN MID LEVEL MOISTURE...THUS
SNOW COVERAGE ACROSS THE SNOWY AND SIERRA MADRE RANGES SHOULD BE
MORE LIMITED.

WEDNESDAY...ANOTHER QUITE WINDY DAY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS. RELATIVELY MILD PER 850 MB AND 700 TEMPERATURES AND
DOWNSLOPE WARMING. ISOLATED TO SCATTERED SNOWS ACROSS OUR NORTHERN
COUNTIES FROM DOUGLAS TO LUSK TO CHADRON.

THANKSGIVING...THE MODELS ARE NOW SHOWING WEST NORTHWEST FLOW ALOFT
WITH OUR COUNTIES IN THE WARM SECTOR...ALONG WITH DOWNSLOPE WEST
WINDS. WILL BLEND WITH OUR NEIGHBORING OFFICE AND KEEP HIGH
TEMPERATURES DOWN...THOUGH LATER SHIFTS WILL NEED TO BETTER ASSESS
THE SITUATION.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 559 AM MST FRI NOV 21 2014

VFR PREVAILS. INCREASING CLOUD COVER THIS
AFTERNOON...WITH SCATTERED TO BROKEN CLOUDS AT OR ABOVE 9000 FEET
AGL.

&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING
     FOR WYZ104-105-116-117.

     HIGH WIND WATCH FROM LATE TONIGHT THROUGH SATURDAY EVENING FOR
     WYZ106-110.

NE...NONE.
&&

$$

SHORT TERM...RJM
LONG TERM...SAR
AVIATION...SAR
FIRE WEATHER...RJM




000
FXUS65 KCYS 211259
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
559 AM MST FRI NOV 21 2014

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

AN ACTIVE PATTERN IS SHAPING UP FOR THE FORECAST AREA THIS
WEEKEND...WITH STRONG WINDS AND MOUNTAIN SNOWS THE MAIN FORECAST
CHALLENGES.

TODAY WILL BE ONE LAST RELATIVELY CALM WEATHER DAY AHEAD OF THE
MAIN PACIFIC STORM SYSTEM THAT WILL SLAM INTO THE PAC NW TODAY AND
MAKE A SOUTHEASTWARD TREK ACROSS THE ROCKIES THROUGH SUNDAY.
MILD...BREEZY AND DRY CONDITIONS WILL OCCUR TODAY IN THE WAKE OF A
WEAK SHORTWAVE TROUGH MOVING OVERHEAD THIS MORNING. FAIRLY STRONG
PRESSURE FALLS OF 4-8 MB/6 HR ARE PROGGED AHEAD OF THE PACIFIC
STORM SYSTEM TONIGHT...WHICH WILL RAPIDLY STRENGTHEN THE SFC
PRESSURE GRADIENT ACROSS SOUTHEAST WYOMING. THE CAG-CPR GRADIENT
LOOKS TO REACH THE MID 60 DAM READINGS BY SUNRISE...AND PEAK TO
MID 80 DAM VALUES BY MIDDAY SATURDAY. THE LLVL INVERSION LOOKS TO
RAPIDLY WEAKEN AND LIFT TO MOUNTAIN TOP LEVEL EARLY SATURDAY
MORNING AS WELL...SO FEEL CONFIDENT THAT THE HIGH WIND EVENT
WILL OCCUR FOR PORTIONS OF SOUTHEAST WYOMING. ISSUED A HIGH WIND
WATCH...STARTING FIRST IN THE ARLINGTON AND BORDEAUX ZONES BEFORE
SUNRISE WHICH ARE MOST SENSITIVE TO RAPID STRENGTHENING OF THE
GRADIENT AND DEVELOPMENT OF MOUNTAIN WAVE ACTIVITY...THEN
EXPANDING TO NORTHERN CARBON AND ALBANY COUNTIES AND THE SOUTHERN
LARAMIE RANGE. LOOKING AT THE POTENTIAL FOR 60 TO 70 MPH GUSTS FOR
THESE AREAS THROUGH THE DAY...WITH PERHAPS SLIGHTLY STRONGER GUSTS
IN THE MORE FAVORED GAP LOCATIONS OF ARLINGTON AND BORDEAUX.
THERE IS POTENTIAL FOR THE NEED TO EXPAND THIS HIGHLIGHT TO THE
NORTHERN LARAMIE RANGE AND WESTERN CONVERSE COUNTY AS WELL...AS
GUIDANCE IS SHOWING RATHER STRONG H7 WINDS IN EXCESS OF 65 KTS
OVER THE NORTHERN LARAMIES. CONFIDENCE IS A BIT LOWER IN THIS
SOLUTION...SO WILL HOLD OFF FOR NOW. THE PACIFIC FRONT WILL MOVE
WEST - EAST ACROSS THE FORECAST AREA AROUND SUNSET ON
SATURDAY...WITH STRONG BORA WINDS CONTINUING FOR A FEW MORE HOURS
BEFORE DIMINISHING OVERNIGHT. COULD SEE GUSTY NORTHWEST WINDS
EXPAND TO THE WYO/NEB PLAINS ON SUNDAY AFTERNOON...AND WILL NEED
TO MONITOR FOR FUTURE HIGHLIGHTS FOR THESE AREA OVER THE COMING
DAY. TEMPERATURES ON SATURDAY WILL BE QUITE MILD OVERALL IN THE
MID 40S TO UPPER 50S FROM WEST TO EAST WITH WAA AND DOWNSLOPE
WINDS IN PLACE...AND WILL COOL FOR SUNDAY BEHIND THE FRONT.

ALONG WITH THE STRONG WINDS...MODERATE TO HEAVY SNOW IS EXPECTED TO
DEVELOP IN THE MOUNTAINS OF SOUTHEAST WYOMING AS THE SYSTEM MOVES
THROUGH SATURDAY AFTERNOON THROUGH SUNDAY. LFQ JET DYNAMICS WILL
INCREASE SATURDAY AFTERNOON ALONG WITH MIDLEVEL PVA...PACIFIC
MOISTURE AND LLVL OROGRAPHIC EFFECTS WITH THE STRONG WINDS IN
PLACE. THE STRONGEST MIDLEVEL VORT MAX WILL TRAVERSE ACROSS THE
CWA SATURDAY NIGHT...WHILE THE JET DIVES SOUTH INTO AZ/NM. SO
EXPECT A HEAVY SNOW EVENT SATURDAY AFTERNOON AND NIGHT...WITH
ACCUMULATIONS AROUND ONE FOOT POSSIBLE IN THE SNOWY AND SIERRA
MADRES. COULD SEE A FEW INCHES AS WELL IN SURROUNDING VALLEYS.
BLOWING SNOW WILL BE A CONCERN WITH STRONG LLVL WINDS IN
PLACE...ALTHOUGH THEY WILL WEAKEN THROUGH THE NIGHT. THE MAIN JET
DYNAMICS WILL THEN REMAIN SOUTH OF OUR AREA ON SUNDAY AND MONDAY
ALTHOUGH MIDLEVEL ENERGY AND PACIFIC MOISTURE WILL CONTINUE TO
STREAM OVERHEAD THROUGH THIS TIME...SO EXPECT CONTINUED PERIODS OF
MODERATE TO HEAVY SNOW TO CONTINUE THROUGH SUNDAY AND MONDAY. WENT
AHEAD AND ISSUED A LONG DURATION WINTER STORM WATCH FOR THE
COMBINATION OF STEADY MODERATE/HEAVY SNOWFALL AND GUSTY WINDS THAT
ARE ANTICIPATED SATURDAY AFTERNOON THROUGH MONDAY FOR THE SNOWY
AND SIERRAS. THE HIGHEST SNOW TOTALS WILL BE ALONG WEST AND
NORTHWEST FACING SLOPES. FURTHER EAST...DOWNSLOPE WARMING AND
DRYING EFFECTS WILL SEVERELY LIMIT PRECIP CHANCES...ALTHOUGH CANT
RULE OUT A FEW SHOWERS IN THE LARAMIE RANGE AND EAST CENTRAL
WYOMING ESPECIALLY WITH THE MAIN PACIFIC FRONT SATURDAY NIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

SUNDAY NIGHT/MONDAY...MOIST NORTHWEST FLOW ALOFT WILL PRODUCE
SCATTERED TO NUMEROUS SNOW SHOWERS OVER THE SNOWY AND SIERRA MADRE
RANGES...MAINLY DRY ELSEWHERE. WINDY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS AND UNIDIRECTIONAL NORTHWEST WINDS.

TUESDAY...NORTHWEST FLOW ALOFT EVEN STRONGER...AND BASED ON
PROJECTED SURFACE THROUGH 700 MB HEIGHTS...SOME AREAS WILL LIKELY
SEE HIGH WIND CRITERIA. SLIGHT DECREASE IN MID LEVEL MOISTURE...THUS
SNOW COVERAGE ACROSS THE SNOWY AND SIERRA MADRE RANGES SHOULD BE
MORE LIMITED.

WEDNESDAY...ANOTHER QUITE WINDY DAY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS. RELATIVELY MILD PER 850 MB AND 700 TEMPERATURES AND
DOWNSLOPE WARMING. ISOLATED TO SCATTERED SNOWS ACROSS OUR NORTHERN
COUNTIES FROM DOUGLAS TO LUSK TO CHADRON.

THANKSGIVING...THE MODELS ARE NOW SHOWING WEST NORTHWEST FLOW ALOFT
WITH OUR COUNTIES IN THE WARM SECTOR...ALONG WITH DOWNSLOPE WEST
WINDS. WILL BLEND WITH OUR NEIGHBORING OFFICE AND KEEP HIGH
TEMPERATURES DOWN...THOUGH LATER SHIFTS WILL NEED TO BETTER ASSESS
THE SITUATION.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 559 AM MST FRI NOV 21 2014

VFR PREVAILS. INCREASING CLOUD COVER THIS
AFTERNOON...WITH SCATTERED TO BROKEN CLOUDS AT OR ABOVE 9000 FEET
AGL.

&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING
     FOR WYZ104-105-116-117.

     HIGH WIND WATCH FROM LATE TONIGHT THROUGH SATURDAY EVENING FOR
     WYZ106-110.

NE...NONE.
&&

$$

SHORT TERM...RJM
LONG TERM...SAR
AVIATION...SAR
FIRE WEATHER...RJM




000
FXUS65 KCYS 211259
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
559 AM MST FRI NOV 21 2014

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

AN ACTIVE PATTERN IS SHAPING UP FOR THE FORECAST AREA THIS
WEEKEND...WITH STRONG WINDS AND MOUNTAIN SNOWS THE MAIN FORECAST
CHALLENGES.

TODAY WILL BE ONE LAST RELATIVELY CALM WEATHER DAY AHEAD OF THE
MAIN PACIFIC STORM SYSTEM THAT WILL SLAM INTO THE PAC NW TODAY AND
MAKE A SOUTHEASTWARD TREK ACROSS THE ROCKIES THROUGH SUNDAY.
MILD...BREEZY AND DRY CONDITIONS WILL OCCUR TODAY IN THE WAKE OF A
WEAK SHORTWAVE TROUGH MOVING OVERHEAD THIS MORNING. FAIRLY STRONG
PRESSURE FALLS OF 4-8 MB/6 HR ARE PROGGED AHEAD OF THE PACIFIC
STORM SYSTEM TONIGHT...WHICH WILL RAPIDLY STRENGTHEN THE SFC
PRESSURE GRADIENT ACROSS SOUTHEAST WYOMING. THE CAG-CPR GRADIENT
LOOKS TO REACH THE MID 60 DAM READINGS BY SUNRISE...AND PEAK TO
MID 80 DAM VALUES BY MIDDAY SATURDAY. THE LLVL INVERSION LOOKS TO
RAPIDLY WEAKEN AND LIFT TO MOUNTAIN TOP LEVEL EARLY SATURDAY
MORNING AS WELL...SO FEEL CONFIDENT THAT THE HIGH WIND EVENT
WILL OCCUR FOR PORTIONS OF SOUTHEAST WYOMING. ISSUED A HIGH WIND
WATCH...STARTING FIRST IN THE ARLINGTON AND BORDEAUX ZONES BEFORE
SUNRISE WHICH ARE MOST SENSITIVE TO RAPID STRENGTHENING OF THE
GRADIENT AND DEVELOPMENT OF MOUNTAIN WAVE ACTIVITY...THEN
EXPANDING TO NORTHERN CARBON AND ALBANY COUNTIES AND THE SOUTHERN
LARAMIE RANGE. LOOKING AT THE POTENTIAL FOR 60 TO 70 MPH GUSTS FOR
THESE AREAS THROUGH THE DAY...WITH PERHAPS SLIGHTLY STRONGER GUSTS
IN THE MORE FAVORED GAP LOCATIONS OF ARLINGTON AND BORDEAUX.
THERE IS POTENTIAL FOR THE NEED TO EXPAND THIS HIGHLIGHT TO THE
NORTHERN LARAMIE RANGE AND WESTERN CONVERSE COUNTY AS WELL...AS
GUIDANCE IS SHOWING RATHER STRONG H7 WINDS IN EXCESS OF 65 KTS
OVER THE NORTHERN LARAMIES. CONFIDENCE IS A BIT LOWER IN THIS
SOLUTION...SO WILL HOLD OFF FOR NOW. THE PACIFIC FRONT WILL MOVE
WEST - EAST ACROSS THE FORECAST AREA AROUND SUNSET ON
SATURDAY...WITH STRONG BORA WINDS CONTINUING FOR A FEW MORE HOURS
BEFORE DIMINISHING OVERNIGHT. COULD SEE GUSTY NORTHWEST WINDS
EXPAND TO THE WYO/NEB PLAINS ON SUNDAY AFTERNOON...AND WILL NEED
TO MONITOR FOR FUTURE HIGHLIGHTS FOR THESE AREA OVER THE COMING
DAY. TEMPERATURES ON SATURDAY WILL BE QUITE MILD OVERALL IN THE
MID 40S TO UPPER 50S FROM WEST TO EAST WITH WAA AND DOWNSLOPE
WINDS IN PLACE...AND WILL COOL FOR SUNDAY BEHIND THE FRONT.

ALONG WITH THE STRONG WINDS...MODERATE TO HEAVY SNOW IS EXPECTED TO
DEVELOP IN THE MOUNTAINS OF SOUTHEAST WYOMING AS THE SYSTEM MOVES
THROUGH SATURDAY AFTERNOON THROUGH SUNDAY. LFQ JET DYNAMICS WILL
INCREASE SATURDAY AFTERNOON ALONG WITH MIDLEVEL PVA...PACIFIC
MOISTURE AND LLVL OROGRAPHIC EFFECTS WITH THE STRONG WINDS IN
PLACE. THE STRONGEST MIDLEVEL VORT MAX WILL TRAVERSE ACROSS THE
CWA SATURDAY NIGHT...WHILE THE JET DIVES SOUTH INTO AZ/NM. SO
EXPECT A HEAVY SNOW EVENT SATURDAY AFTERNOON AND NIGHT...WITH
ACCUMULATIONS AROUND ONE FOOT POSSIBLE IN THE SNOWY AND SIERRA
MADRES. COULD SEE A FEW INCHES AS WELL IN SURROUNDING VALLEYS.
BLOWING SNOW WILL BE A CONCERN WITH STRONG LLVL WINDS IN
PLACE...ALTHOUGH THEY WILL WEAKEN THROUGH THE NIGHT. THE MAIN JET
DYNAMICS WILL THEN REMAIN SOUTH OF OUR AREA ON SUNDAY AND MONDAY
ALTHOUGH MIDLEVEL ENERGY AND PACIFIC MOISTURE WILL CONTINUE TO
STREAM OVERHEAD THROUGH THIS TIME...SO EXPECT CONTINUED PERIODS OF
MODERATE TO HEAVY SNOW TO CONTINUE THROUGH SUNDAY AND MONDAY. WENT
AHEAD AND ISSUED A LONG DURATION WINTER STORM WATCH FOR THE
COMBINATION OF STEADY MODERATE/HEAVY SNOWFALL AND GUSTY WINDS THAT
ARE ANTICIPATED SATURDAY AFTERNOON THROUGH MONDAY FOR THE SNOWY
AND SIERRAS. THE HIGHEST SNOW TOTALS WILL BE ALONG WEST AND
NORTHWEST FACING SLOPES. FURTHER EAST...DOWNSLOPE WARMING AND
DRYING EFFECTS WILL SEVERELY LIMIT PRECIP CHANCES...ALTHOUGH CANT
RULE OUT A FEW SHOWERS IN THE LARAMIE RANGE AND EAST CENTRAL
WYOMING ESPECIALLY WITH THE MAIN PACIFIC FRONT SATURDAY NIGHT.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 559 AM MST FRI NOV 21 2014

SUNDAY NIGHT/MONDAY...MOIST NORTHWEST FLOW ALOFT WILL PRODUCE
SCATTERED TO NUMEROUS SNOW SHOWERS OVER THE SNOWY AND SIERRA MADRE
RANGES...MAINLY DRY ELSEWHERE. WINDY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS AND UNIDIRECTIONAL NORTHWEST WINDS.

TUESDAY...NORTHWEST FLOW ALOFT EVEN STRONGER...AND BASED ON
PROJECTED SURFACE THROUGH 700 MB HEIGHTS...SOME AREAS WILL LIKELY
SEE HIGH WIND CRITERIA. SLIGHT DECREASE IN MID LEVEL MOISTURE...THUS
SNOW COVERAGE ACROSS THE SNOWY AND SIERRA MADRE RANGES SHOULD BE
MORE LIMITED.

WEDNESDAY...ANOTHER QUITE WINDY DAY PER PROGGED SURFACE THROUGH 700
MB GRADIENTS. RELATIVELY MILD PER 850 MB AND 700 TEMPERATURES AND
DOWNSLOPE WARMING. ISOLATED TO SCATTERED SNOWS ACROSS OUR NORTHERN
COUNTIES FROM DOUGLAS TO LUSK TO CHADRON.

THANKSGIVING...THE MODELS ARE NOW SHOWING WEST NORTHWEST FLOW ALOFT
WITH OUR COUNTIES IN THE WARM SECTOR...ALONG WITH DOWNSLOPE WEST
WINDS. WILL BLEND WITH OUR NEIGHBORING OFFICE AND KEEP HIGH
TEMPERATURES DOWN...THOUGH LATER SHIFTS WILL NEED TO BETTER ASSESS
THE SITUATION.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 559 AM MST FRI NOV 21 2014

VFR PREVAILS. INCREASING CLOUD COVER THIS
AFTERNOON...WITH SCATTERED TO BROKEN CLOUDS AT OR ABOVE 9000 FEET
AGL.

&&

.FIRE WEATHER...
ISSUED AT 559 AM MST FRI NOV 21 2014

ONE LAST MILD...BREEZY AND DRY DAY IS EXPECTED FOR THE DISTRICT
TODAY. STRONG WINDS AND PERIODS OF SNOW WILL OCCUR IN AND NEAR THE
MOUNTAINS OF SOUTHEAST WYOMING THROUGH MIDDLE OF NEXT WEEK. WINDY
CONDITIONS WILL EXPAND TO THE PLAINS ON SUNDAY AND WILL CONTINUE
THROUGH MIDWEEK AS WELL

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING
     FOR WYZ104-105-116-117.

     HIGH WIND WATCH FROM LATE TONIGHT THROUGH SATURDAY EVENING FOR
     WYZ106-110.

NE...NONE.
&&

$$

SHORT TERM...RJM
LONG TERM...SAR
AVIATION...SAR
FIRE WEATHER...RJM




000
FXUS65 KCYS 211140
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
440 AM MST FRI NOV 21 2014

.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 230 PM MST THU NOV 20 2014

BATCH OF MOISTURE EVIDENT ACROSS MUCH OF WESTERN WYOMING WILL
SHIFT EAST ACROSS THE CWA OVERNIGHT ALONG WITH A WEAK UPPER
IMPULSE. NOT MUCH EFFECT FROM THIS OTHER THAN SOME MTN SNOW
SHOWERS MAINLY THIS EVENING.

FRIDAY WILL BE ANOTHER FAIRLY MILD AND DRY DAY ACROSS THE CWA
UNDER A GENERALLY WESTERLY FLOW ALOFT. WINDS COULD GET A LITTLE
GUSTY AROUND THE MTNS IN THE AFTERNOON AS SOME 40KT WINDS AT 700MB
PASS ACROSS BUT NOT LOOKING TOO SIGNIFICANT. MUCH MORE SIGNIFICANT
WINDS LOOK TO DEVELOP LATE FRIDAY NIGHT AND SATURDAY AS THE
STRONGER WESTERLIES ALOFT SAG SOUTH OVER THE AREA AND AN
APPROACHING SHORTWAVE INDUCES PRESSURE FALLS OVER THE HIGH PLAINS
INCREASING THE PRESSURE GRADIENT. LOW LEVEL INVERSION SHOULD KEEP
THE STRONGER WINDS OFF THE SFC THROUGH EARLY SATURDAY THEN THE
WINDS SHOULD INCREASE DURING THE DAY AS THE INVERSION IS LOST.
EARLIER FORECAST REASONING LOOKS ON TRACK WITH THE ARLINGTON/BORDEAUX
AREAS LIKELY SEEING THE INITIAL STRONG WINDS AS 700MB WINDS
INCREASE TO OVER 60KTS...WITH OTHER AREAS LIKELY HOLDING OFF UNTIL
A PACIFIC FRONT PASSES ACROSS IN THE LATE AFTERNOON. GIVEN LATER
PERIODS AND TIMING UNCERTAINTIES WILL HOLD OFF ON A WATCH FOR NOW
THOUGH SOME HIGHLIGHTS WILL VERY LIKELY BE NEEDED EVENTUALLY.
OTHERWISE NEXT SLUG OF MOISTURE SHOULD REACH WESTERN PARTS OF THE
CWA SATURDAY AFTERNOON WITH SNOW SHOWERS INCREASING OVER THAT AREA
THROUGH SATURDAY EVENING.

.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 230 PM MST THU NOV 20 2014

MEDIUM RANGE MODEL GUIDANCE IS IN GOOD AGREEMENT WITH BROAD SCALE
TROUGHING OVER THE CENTRAL US INTO EARLY NEXT WEEK. THIS RESULTS IN
FAST NORTHWEST FLOW ALOFT ANCHORED OVER THE WESTERN STATES FOR MUCH
OF THE EXTENDED PERIOD. A VERY ACTIVE WEATHER PATTERN SHOULD PREVAIL
THROUGH THE PERIOD. NUMEROUS SHOTS OF MID LEVEL MOISTURE WILL
OCCUR WITH SMALLER SCALE DISTURBANCES EMBEDDED WITHIN THE
FLOW...EVIDENCED BY MODELED 700-300 MILLIBAR RH FIELDS. FAVORABLE
OROGRAPHICS LIKELY FOR THE SNOWIES AND SIERRA MADRES THROUGH AT
LEAST TUE WITHIN MOIST NORTHWEST FLOW REGIME...SO MOUNTAIN SNOW
AMOUNTS COULD ACTUALLY GET QUITE HIGH OVER THE COURSE OF SEVERAL
DAYS. WINTER HEADLINES COULD BE NECESSARY IN THE FUTURE. A WINDY
PATTERN TOO WITH MULTIPLE HIGH WIND EPISODES POSSIBLE. GFS AND
ECMWF DIVERGE CONSIDERABLY INTO THE MIDDLE PART OF NEXT WEEK. GFS
SHOWS THE CWA ON THE EASTERN FRINGE OF AN AMPLIFYING UPPER RIDGE
ALONG THE WEST COAST. THE ECMWF SHOWS THE H25 JET CORE DIRECTLY
OVERHEAD. REGARDLESS...THE STRENGTH OF THIS JET IS PROGGED TO BE
IMPRESSIVE WITH 155+ KT AT H25 SOMEWHERE TO THE NORTHEAST. BOTH
SOLUTIONS PLACE THE CWA UNDER INTENSE SUBSIDENCE IN THE RIGHT EXIT
REGION ON TUE NIGHT AND WED. THIS WOULD BE THE MOST LIKELY TIME
FOR A WIDESPREAD WIND EVENT WITH GFS H85 CAG-CPR GRADIENTS AROUND
60 METERS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 830 PM MST THU NOV 20 2014

VFR CONDITIONS WILL PREVAIL THROUGH FRIDAY. ABUNDANT MID/UPPER
LEVEL CLOUDINESS ASSOCIATED WITH A PASSING PACIFIC DISTURBANCE
WILL GRADUALLY CLEAR FROM WEST TO EAST FRIDAY MORNING. LOWEST
CELINGS TONIGHT WILL RANGE BETWEEN 8000 AND 10000 FT AGL...WITH
THE MOUNTAIN TOPS OBSCURED. WINDS OUTSIDE THE MOUNTAIN ZONES WILL
BE LIGHT OVERNIGHT. BREEZY WEST WINDS WILL THEN SPREAD ACROSS
MUCH OF SOUTHEAST WY FRIDAY MORNING AND CONTINUE THROUGH THE
AFTERNOON.


&&

.FIRE WEATHER...
ISSUED AT 230 PM MST THU NOV 20 2014

NO CONCERNS ANTICIPATED THROUGH SATURDAY AS WEATHER FACTORS WILL
BE NON-CRITICAL. AFTER THAT PERIODS OF STRONG WINDS SHOULD OCCUR
AROUND THE MOUNTAINS SUNDAY INTO NEXT WEEK BUT NO OTHER FACTORS
ARE EXPECTED TO RAISE CONCERNS.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING
     FOR WYZ104-105-116-117.

     HIGH WIND WATCH FROM LATE TONIGHT THROUGH SATURDAY EVENING FOR
     WYZ106-110.

NE...NONE.
&&

$$

SHORT TERM...RAE
LONG TERM...CLH
AVIATION...MJ
FIRE WEATHER...RAE




000
FXUS65 KCYS 211140
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
440 AM MST FRI NOV 21 2014

.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 230 PM MST THU NOV 20 2014

BATCH OF MOISTURE EVIDENT ACROSS MUCH OF WESTERN WYOMING WILL
SHIFT EAST ACROSS THE CWA OVERNIGHT ALONG WITH A WEAK UPPER
IMPULSE. NOT MUCH EFFECT FROM THIS OTHER THAN SOME MTN SNOW
SHOWERS MAINLY THIS EVENING.

FRIDAY WILL BE ANOTHER FAIRLY MILD AND DRY DAY ACROSS THE CWA
UNDER A GENERALLY WESTERLY FLOW ALOFT. WINDS COULD GET A LITTLE
GUSTY AROUND THE MTNS IN THE AFTERNOON AS SOME 40KT WINDS AT 700MB
PASS ACROSS BUT NOT LOOKING TOO SIGNIFICANT. MUCH MORE SIGNIFICANT
WINDS LOOK TO DEVELOP LATE FRIDAY NIGHT AND SATURDAY AS THE
STRONGER WESTERLIES ALOFT SAG SOUTH OVER THE AREA AND AN
APPROACHING SHORTWAVE INDUCES PRESSURE FALLS OVER THE HIGH PLAINS
INCREASING THE PRESSURE GRADIENT. LOW LEVEL INVERSION SHOULD KEEP
THE STRONGER WINDS OFF THE SFC THROUGH EARLY SATURDAY THEN THE
WINDS SHOULD INCREASE DURING THE DAY AS THE INVERSION IS LOST.
EARLIER FORECAST REASONING LOOKS ON TRACK WITH THE ARLINGTON/BORDEAUX
AREAS LIKELY SEEING THE INITIAL STRONG WINDS AS 700MB WINDS
INCREASE TO OVER 60KTS...WITH OTHER AREAS LIKELY HOLDING OFF UNTIL
A PACIFIC FRONT PASSES ACROSS IN THE LATE AFTERNOON. GIVEN LATER
PERIODS AND TIMING UNCERTAINTIES WILL HOLD OFF ON A WATCH FOR NOW
THOUGH SOME HIGHLIGHTS WILL VERY LIKELY BE NEEDED EVENTUALLY.
OTHERWISE NEXT SLUG OF MOISTURE SHOULD REACH WESTERN PARTS OF THE
CWA SATURDAY AFTERNOON WITH SNOW SHOWERS INCREASING OVER THAT AREA
THROUGH SATURDAY EVENING.

.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 230 PM MST THU NOV 20 2014

MEDIUM RANGE MODEL GUIDANCE IS IN GOOD AGREEMENT WITH BROAD SCALE
TROUGHING OVER THE CENTRAL US INTO EARLY NEXT WEEK. THIS RESULTS IN
FAST NORTHWEST FLOW ALOFT ANCHORED OVER THE WESTERN STATES FOR MUCH
OF THE EXTENDED PERIOD. A VERY ACTIVE WEATHER PATTERN SHOULD PREVAIL
THROUGH THE PERIOD. NUMEROUS SHOTS OF MID LEVEL MOISTURE WILL
OCCUR WITH SMALLER SCALE DISTURBANCES EMBEDDED WITHIN THE
FLOW...EVIDENCED BY MODELED 700-300 MILLIBAR RH FIELDS. FAVORABLE
OROGRAPHICS LIKELY FOR THE SNOWIES AND SIERRA MADRES THROUGH AT
LEAST TUE WITHIN MOIST NORTHWEST FLOW REGIME...SO MOUNTAIN SNOW
AMOUNTS COULD ACTUALLY GET QUITE HIGH OVER THE COURSE OF SEVERAL
DAYS. WINTER HEADLINES COULD BE NECESSARY IN THE FUTURE. A WINDY
PATTERN TOO WITH MULTIPLE HIGH WIND EPISODES POSSIBLE. GFS AND
ECMWF DIVERGE CONSIDERABLY INTO THE MIDDLE PART OF NEXT WEEK. GFS
SHOWS THE CWA ON THE EASTERN FRINGE OF AN AMPLIFYING UPPER RIDGE
ALONG THE WEST COAST. THE ECMWF SHOWS THE H25 JET CORE DIRECTLY
OVERHEAD. REGARDLESS...THE STRENGTH OF THIS JET IS PROGGED TO BE
IMPRESSIVE WITH 155+ KT AT H25 SOMEWHERE TO THE NORTHEAST. BOTH
SOLUTIONS PLACE THE CWA UNDER INTENSE SUBSIDENCE IN THE RIGHT EXIT
REGION ON TUE NIGHT AND WED. THIS WOULD BE THE MOST LIKELY TIME
FOR A WIDESPREAD WIND EVENT WITH GFS H85 CAG-CPR GRADIENTS AROUND
60 METERS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 830 PM MST THU NOV 20 2014

VFR CONDITIONS WILL PREVAIL THROUGH FRIDAY. ABUNDANT MID/UPPER
LEVEL CLOUDINESS ASSOCIATED WITH A PASSING PACIFIC DISTURBANCE
WILL GRADUALLY CLEAR FROM WEST TO EAST FRIDAY MORNING. LOWEST
CELINGS TONIGHT WILL RANGE BETWEEN 8000 AND 10000 FT AGL...WITH
THE MOUNTAIN TOPS OBSCURED. WINDS OUTSIDE THE MOUNTAIN ZONES WILL
BE LIGHT OVERNIGHT. BREEZY WEST WINDS WILL THEN SPREAD ACROSS
MUCH OF SOUTHEAST WY FRIDAY MORNING AND CONTINUE THROUGH THE
AFTERNOON.


&&

.FIRE WEATHER...
ISSUED AT 230 PM MST THU NOV 20 2014

NO CONCERNS ANTICIPATED THROUGH SATURDAY AS WEATHER FACTORS WILL
BE NON-CRITICAL. AFTER THAT PERIODS OF STRONG WINDS SHOULD OCCUR
AROUND THE MOUNTAINS SUNDAY INTO NEXT WEEK BUT NO OTHER FACTORS
ARE EXPECTED TO RAISE CONCERNS.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR WYZ112-114.

     HIGH WIND WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING
     FOR WYZ104-105-116-117.

     HIGH WIND WATCH FROM LATE TONIGHT THROUGH SATURDAY EVENING FOR
     WYZ106-110.

NE...NONE.
&&

$$

SHORT TERM...RAE
LONG TERM...CLH
AVIATION...MJ
FIRE WEATHER...RAE



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