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000
FXUS65 KCYS 272327
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
427 PM MST FRI FEB 27 2015

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 353 PM MST FRI FEB 27 2015

CLOUDS HAVE HUNG ON ACROSS EXTREME SE WY INTO MUCH OF THE
PANHANDLE THIS AFTERNOON WITH A FEW FLURRIES NOTED AS WELL.
EXPECT GENERALLY QUIET WEATHER ACROSS THE CWA OVERNIGHT THROUGH
MUCH OF SATURDAY BUT CHILLY TEMPERATURES WILL PERSIST. A FEW
FLURRIES STILL POSSIBLE MAINLY NEAR THE COLORADO BORDER THIS
EVENING DUE TO THE UPSLOPE PATTERN INDUCED BY THE CHEYENNE RIDGE.

EXPECT TO SEE LIGHT SNOW INCREASE FROM THE SW AGAIN LATE SATURDAY
AS AN IMPULSE RIDES ENE FROM AN UPPER LOW ALONG THE CALIFORNIA
COAST AND SFC UPSLOPE STEPS UP A BIT IN RESPONSE TO AN INCREASING
SFC PRESSURE GRADIENT MAINLY ACROSS SRN WY. BETTER UPPER DYNAMICS
APPEAR THEY WILL REMAIN SOUTH OF THE CWA SO PATTERN SIMILAR TO
LAST NIGHT WHERE SNOW WILL LIKELY BE LIGHT IN NATURE WITH GROWTH
RATES NOT ALL THAT IMPRESSIVE. A GENERAL 1-3 INCHES LOOKS A DECENT
BET ACROSS THE SRN PART OF THE CWA SAT NIGHT INTO SUNDAY MORNING
BEFORE ENDING. TEMPERATURES WILL REMAIN COLD THROUGH THE WEEKEND
AS THE SFC HIGH SETTLES DOWN THE HIGH PLAINS. MAINLY DRY SUNDAY
AFTERNOON AND NIGHT AS SHORT RIDGING NOSES ACROSS THE AREA FROM
COLORADO.

.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 353 PM MST FRI FEB 27 2015

AN ENERGETIC PATTERN SHAPING UP EARLY NEXT WEEK AS A SERIES OF
SHORTWAVES RIDE THE NOSE OF THE POLAR JET INTO THE INTERMOUNTAIN
WEST. OUTSIDE OF THE MOUNTAINS...MONDAY ACTUALLY LOOKS TO BE DRY
AND LIKELY ABOVE FREEZING IN LOWER ELEVATIONS. THE SNOWY/SIERRA
MADRE RANGES WILL BEGIN TO SEE SNOW DURING THE DAY ON MONDAY AS
THE PREVIOUSLY CUT-OFF GREAT BASIN UPPER LOW PHASES WITH THE NRN
STREAM. MOIST OROGRAPHIC FLOW WILL ENSUE AHEAD OF THIS FTR
RESULTING IN THE MOUNTAINS SNOWS. SEVERAL INCHES WILL POSSIBLE IN
THE HIER TERRAIN BY SUNSET MONDAY. 12Z MODELS PROG THE MOISTURE
TO HOLD OFF ACROSS THE PLAINS/VALLEYS UNTIL THE AFOREMENTIONED
SHORTWAVE TROUGH RIDES ATOP A SOUTH-MOVING COLD FRONT MONDAY NT.
THE INITIAL SHORTWAVE TROF SLIDES EAST FOR TUESDAY WITH A
SECONDARY SHORTWAVE MOVING INTO THE REGION PROLONGING SNOW
ACCUMULATIONS ACROSS THE AREA. THE POTENTIAL EXISTS FOR SOME
SIGNIFICANT ACCUMULATIONS LATE MONDAY INTO TUESDAY ESPECIALLY OVR
THE HIER TERRAIN. THE OTHER PART OF THIS EVENT THAT WILL HAVE
IMPACTS WILL BE THE VERY COLD TEMPERATURES THAT WILL LAST TUESDAY
AND WEDNESDAY AS 1040MB SETTLES RIGHT OVER THE AREA. MODELS PROG
-25C AT H7 IN THE CORE OF THE ARCTIC AIR MASS. THE RESULT WILL BE
FOR HIGH TEMPERATURES THAT WILL ONLY REACH THE TEENS TUE-WED WITH
LOWS TUESDAY NIGHT LIKELY NEGATIVE SINGLE DIGITS BELOW ZERO...AND
EVEN THAT IS PROBABLY BEING OPTIMISTIC. FORTUNATELY THE SNOW WILL
COME TO AN END BY LATE TUESDAY. DRY CONDITIONS AND MODERATING
TEMPERATURES RETURN THU-FRI AS FLOW FLATTENS WHILE THE PATTERN
DE-AMPLIFIES. IN FACT...EXPECT HIGH TEMPERATURES TO RETURN INTO
THE 40S BY FRIDAY. BREEZY CONDITIONS WILL ACCOMPANY THESE WARMER
TEMPERATURES ACROSS SE WYOMING THU-FRI.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 423 PM MST FRI FEB 27 2015

CONFIDENCE IS FAIRLY HIGH THAT IFR CEILINGS WILL RETURN TO KCYS
THIS EVENING AFTER SUNSET. THIS IS BACKED UP BY LATEST HRRR
GUIDANCE WHICH KEEPS IFR CONDITIONS AT KCYS THROUGH 09Z TONIGHT.
ANOTHER COLD FRONT LOOKS TO MOVE INTO THE AREA SATURDAY
MORNING...WITH NORTHEASTERLY UPSLOPING WINDS RETURNING. COULD BE
SEEING IFR CONDITIONS WITH THESE UPSLOPE WINDS...PARTICUALRLY
ACROSS THE SOUTHERN PANHANDLE AND HERE AT KCYS.

&&

.FIRE WEATHER...
ISSUED AT 353 PM MST FRI FEB 27 2015

NO CONCERNS ANTICIPATED INTO EARLY NEXT WEEK WITH COOL TO COLD
TEMPERATURES AND PERIODS OF SNOW KEEPING CONDITIONS NON-CRITICAL.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

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




000
FXUS65 KCYS 272327
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
427 PM MST FRI FEB 27 2015

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 353 PM MST FRI FEB 27 2015

CLOUDS HAVE HUNG ON ACROSS EXTREME SE WY INTO MUCH OF THE
PANHANDLE THIS AFTERNOON WITH A FEW FLURRIES NOTED AS WELL.
EXPECT GENERALLY QUIET WEATHER ACROSS THE CWA OVERNIGHT THROUGH
MUCH OF SATURDAY BUT CHILLY TEMPERATURES WILL PERSIST. A FEW
FLURRIES STILL POSSIBLE MAINLY NEAR THE COLORADO BORDER THIS
EVENING DUE TO THE UPSLOPE PATTERN INDUCED BY THE CHEYENNE RIDGE.

EXPECT TO SEE LIGHT SNOW INCREASE FROM THE SW AGAIN LATE SATURDAY
AS AN IMPULSE RIDES ENE FROM AN UPPER LOW ALONG THE CALIFORNIA
COAST AND SFC UPSLOPE STEPS UP A BIT IN RESPONSE TO AN INCREASING
SFC PRESSURE GRADIENT MAINLY ACROSS SRN WY. BETTER UPPER DYNAMICS
APPEAR THEY WILL REMAIN SOUTH OF THE CWA SO PATTERN SIMILAR TO
LAST NIGHT WHERE SNOW WILL LIKELY BE LIGHT IN NATURE WITH GROWTH
RATES NOT ALL THAT IMPRESSIVE. A GENERAL 1-3 INCHES LOOKS A DECENT
BET ACROSS THE SRN PART OF THE CWA SAT NIGHT INTO SUNDAY MORNING
BEFORE ENDING. TEMPERATURES WILL REMAIN COLD THROUGH THE WEEKEND
AS THE SFC HIGH SETTLES DOWN THE HIGH PLAINS. MAINLY DRY SUNDAY
AFTERNOON AND NIGHT AS SHORT RIDGING NOSES ACROSS THE AREA FROM
COLORADO.

.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 353 PM MST FRI FEB 27 2015

AN ENERGETIC PATTERN SHAPING UP EARLY NEXT WEEK AS A SERIES OF
SHORTWAVES RIDE THE NOSE OF THE POLAR JET INTO THE INTERMOUNTAIN
WEST. OUTSIDE OF THE MOUNTAINS...MONDAY ACTUALLY LOOKS TO BE DRY
AND LIKELY ABOVE FREEZING IN LOWER ELEVATIONS. THE SNOWY/SIERRA
MADRE RANGES WILL BEGIN TO SEE SNOW DURING THE DAY ON MONDAY AS
THE PREVIOUSLY CUT-OFF GREAT BASIN UPPER LOW PHASES WITH THE NRN
STREAM. MOIST OROGRAPHIC FLOW WILL ENSUE AHEAD OF THIS FTR
RESULTING IN THE MOUNTAINS SNOWS. SEVERAL INCHES WILL POSSIBLE IN
THE HIER TERRAIN BY SUNSET MONDAY. 12Z MODELS PROG THE MOISTURE
TO HOLD OFF ACROSS THE PLAINS/VALLEYS UNTIL THE AFOREMENTIONED
SHORTWAVE TROUGH RIDES ATOP A SOUTH-MOVING COLD FRONT MONDAY NT.
THE INITIAL SHORTWAVE TROF SLIDES EAST FOR TUESDAY WITH A
SECONDARY SHORTWAVE MOVING INTO THE REGION PROLONGING SNOW
ACCUMULATIONS ACROSS THE AREA. THE POTENTIAL EXISTS FOR SOME
SIGNIFICANT ACCUMULATIONS LATE MONDAY INTO TUESDAY ESPECIALLY OVR
THE HIER TERRAIN. THE OTHER PART OF THIS EVENT THAT WILL HAVE
IMPACTS WILL BE THE VERY COLD TEMPERATURES THAT WILL LAST TUESDAY
AND WEDNESDAY AS 1040MB SETTLES RIGHT OVER THE AREA. MODELS PROG
-25C AT H7 IN THE CORE OF THE ARCTIC AIR MASS. THE RESULT WILL BE
FOR HIGH TEMPERATURES THAT WILL ONLY REACH THE TEENS TUE-WED WITH
LOWS TUESDAY NIGHT LIKELY NEGATIVE SINGLE DIGITS BELOW ZERO...AND
EVEN THAT IS PROBABLY BEING OPTIMISTIC. FORTUNATELY THE SNOW WILL
COME TO AN END BY LATE TUESDAY. DRY CONDITIONS AND MODERATING
TEMPERATURES RETURN THU-FRI AS FLOW FLATTENS WHILE THE PATTERN
DE-AMPLIFIES. IN FACT...EXPECT HIGH TEMPERATURES TO RETURN INTO
THE 40S BY FRIDAY. BREEZY CONDITIONS WILL ACCOMPANY THESE WARMER
TEMPERATURES ACROSS SE WYOMING THU-FRI.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 423 PM MST FRI FEB 27 2015

CONFIDENCE IS FAIRLY HIGH THAT IFR CEILINGS WILL RETURN TO KCYS
THIS EVENING AFTER SUNSET. THIS IS BACKED UP BY LATEST HRRR
GUIDANCE WHICH KEEPS IFR CONDITIONS AT KCYS THROUGH 09Z TONIGHT.
ANOTHER COLD FRONT LOOKS TO MOVE INTO THE AREA SATURDAY
MORNING...WITH NORTHEASTERLY UPSLOPING WINDS RETURNING. COULD BE
SEEING IFR CONDITIONS WITH THESE UPSLOPE WINDS...PARTICUALRLY
ACROSS THE SOUTHERN PANHANDLE AND HERE AT KCYS.

&&

.FIRE WEATHER...
ISSUED AT 353 PM MST FRI FEB 27 2015

NO CONCERNS ANTICIPATED INTO EARLY NEXT WEEK WITH COOL TO COLD
TEMPERATURES AND PERIODS OF SNOW KEEPING CONDITIONS NON-CRITICAL.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

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




000
FXUS65 KCYS 272327
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
427 PM MST FRI FEB 27 2015

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 353 PM MST FRI FEB 27 2015

CLOUDS HAVE HUNG ON ACROSS EXTREME SE WY INTO MUCH OF THE
PANHANDLE THIS AFTERNOON WITH A FEW FLURRIES NOTED AS WELL.
EXPECT GENERALLY QUIET WEATHER ACROSS THE CWA OVERNIGHT THROUGH
MUCH OF SATURDAY BUT CHILLY TEMPERATURES WILL PERSIST. A FEW
FLURRIES STILL POSSIBLE MAINLY NEAR THE COLORADO BORDER THIS
EVENING DUE TO THE UPSLOPE PATTERN INDUCED BY THE CHEYENNE RIDGE.

EXPECT TO SEE LIGHT SNOW INCREASE FROM THE SW AGAIN LATE SATURDAY
AS AN IMPULSE RIDES ENE FROM AN UPPER LOW ALONG THE CALIFORNIA
COAST AND SFC UPSLOPE STEPS UP A BIT IN RESPONSE TO AN INCREASING
SFC PRESSURE GRADIENT MAINLY ACROSS SRN WY. BETTER UPPER DYNAMICS
APPEAR THEY WILL REMAIN SOUTH OF THE CWA SO PATTERN SIMILAR TO
LAST NIGHT WHERE SNOW WILL LIKELY BE LIGHT IN NATURE WITH GROWTH
RATES NOT ALL THAT IMPRESSIVE. A GENERAL 1-3 INCHES LOOKS A DECENT
BET ACROSS THE SRN PART OF THE CWA SAT NIGHT INTO SUNDAY MORNING
BEFORE ENDING. TEMPERATURES WILL REMAIN COLD THROUGH THE WEEKEND
AS THE SFC HIGH SETTLES DOWN THE HIGH PLAINS. MAINLY DRY SUNDAY
AFTERNOON AND NIGHT AS SHORT RIDGING NOSES ACROSS THE AREA FROM
COLORADO.

.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 353 PM MST FRI FEB 27 2015

AN ENERGETIC PATTERN SHAPING UP EARLY NEXT WEEK AS A SERIES OF
SHORTWAVES RIDE THE NOSE OF THE POLAR JET INTO THE INTERMOUNTAIN
WEST. OUTSIDE OF THE MOUNTAINS...MONDAY ACTUALLY LOOKS TO BE DRY
AND LIKELY ABOVE FREEZING IN LOWER ELEVATIONS. THE SNOWY/SIERRA
MADRE RANGES WILL BEGIN TO SEE SNOW DURING THE DAY ON MONDAY AS
THE PREVIOUSLY CUT-OFF GREAT BASIN UPPER LOW PHASES WITH THE NRN
STREAM. MOIST OROGRAPHIC FLOW WILL ENSUE AHEAD OF THIS FTR
RESULTING IN THE MOUNTAINS SNOWS. SEVERAL INCHES WILL POSSIBLE IN
THE HIER TERRAIN BY SUNSET MONDAY. 12Z MODELS PROG THE MOISTURE
TO HOLD OFF ACROSS THE PLAINS/VALLEYS UNTIL THE AFOREMENTIONED
SHORTWAVE TROUGH RIDES ATOP A SOUTH-MOVING COLD FRONT MONDAY NT.
THE INITIAL SHORTWAVE TROF SLIDES EAST FOR TUESDAY WITH A
SECONDARY SHORTWAVE MOVING INTO THE REGION PROLONGING SNOW
ACCUMULATIONS ACROSS THE AREA. THE POTENTIAL EXISTS FOR SOME
SIGNIFICANT ACCUMULATIONS LATE MONDAY INTO TUESDAY ESPECIALLY OVR
THE HIER TERRAIN. THE OTHER PART OF THIS EVENT THAT WILL HAVE
IMPACTS WILL BE THE VERY COLD TEMPERATURES THAT WILL LAST TUESDAY
AND WEDNESDAY AS 1040MB SETTLES RIGHT OVER THE AREA. MODELS PROG
-25C AT H7 IN THE CORE OF THE ARCTIC AIR MASS. THE RESULT WILL BE
FOR HIGH TEMPERATURES THAT WILL ONLY REACH THE TEENS TUE-WED WITH
LOWS TUESDAY NIGHT LIKELY NEGATIVE SINGLE DIGITS BELOW ZERO...AND
EVEN THAT IS PROBABLY BEING OPTIMISTIC. FORTUNATELY THE SNOW WILL
COME TO AN END BY LATE TUESDAY. DRY CONDITIONS AND MODERATING
TEMPERATURES RETURN THU-FRI AS FLOW FLATTENS WHILE THE PATTERN
DE-AMPLIFIES. IN FACT...EXPECT HIGH TEMPERATURES TO RETURN INTO
THE 40S BY FRIDAY. BREEZY CONDITIONS WILL ACCOMPANY THESE WARMER
TEMPERATURES ACROSS SE WYOMING THU-FRI.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 423 PM MST FRI FEB 27 2015

CONFIDENCE IS FAIRLY HIGH THAT IFR CEILINGS WILL RETURN TO KCYS
THIS EVENING AFTER SUNSET. THIS IS BACKED UP BY LATEST HRRR
GUIDANCE WHICH KEEPS IFR CONDITIONS AT KCYS THROUGH 09Z TONIGHT.
ANOTHER COLD FRONT LOOKS TO MOVE INTO THE AREA SATURDAY
MORNING...WITH NORTHEASTERLY UPSLOPING WINDS RETURNING. COULD BE
SEEING IFR CONDITIONS WITH THESE UPSLOPE WINDS...PARTICUALRLY
ACROSS THE SOUTHERN PANHANDLE AND HERE AT KCYS.

&&

.FIRE WEATHER...
ISSUED AT 353 PM MST FRI FEB 27 2015

NO CONCERNS ANTICIPATED INTO EARLY NEXT WEEK WITH COOL TO COLD
TEMPERATURES AND PERIODS OF SNOW KEEPING CONDITIONS NON-CRITICAL.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

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




000
FXUS65 KCYS 272327
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
427 PM MST FRI FEB 27 2015

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 353 PM MST FRI FEB 27 2015

CLOUDS HAVE HUNG ON ACROSS EXTREME SE WY INTO MUCH OF THE
PANHANDLE THIS AFTERNOON WITH A FEW FLURRIES NOTED AS WELL.
EXPECT GENERALLY QUIET WEATHER ACROSS THE CWA OVERNIGHT THROUGH
MUCH OF SATURDAY BUT CHILLY TEMPERATURES WILL PERSIST. A FEW
FLURRIES STILL POSSIBLE MAINLY NEAR THE COLORADO BORDER THIS
EVENING DUE TO THE UPSLOPE PATTERN INDUCED BY THE CHEYENNE RIDGE.

EXPECT TO SEE LIGHT SNOW INCREASE FROM THE SW AGAIN LATE SATURDAY
AS AN IMPULSE RIDES ENE FROM AN UPPER LOW ALONG THE CALIFORNIA
COAST AND SFC UPSLOPE STEPS UP A BIT IN RESPONSE TO AN INCREASING
SFC PRESSURE GRADIENT MAINLY ACROSS SRN WY. BETTER UPPER DYNAMICS
APPEAR THEY WILL REMAIN SOUTH OF THE CWA SO PATTERN SIMILAR TO
LAST NIGHT WHERE SNOW WILL LIKELY BE LIGHT IN NATURE WITH GROWTH
RATES NOT ALL THAT IMPRESSIVE. A GENERAL 1-3 INCHES LOOKS A DECENT
BET ACROSS THE SRN PART OF THE CWA SAT NIGHT INTO SUNDAY MORNING
BEFORE ENDING. TEMPERATURES WILL REMAIN COLD THROUGH THE WEEKEND
AS THE SFC HIGH SETTLES DOWN THE HIGH PLAINS. MAINLY DRY SUNDAY
AFTERNOON AND NIGHT AS SHORT RIDGING NOSES ACROSS THE AREA FROM
COLORADO.

.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 353 PM MST FRI FEB 27 2015

AN ENERGETIC PATTERN SHAPING UP EARLY NEXT WEEK AS A SERIES OF
SHORTWAVES RIDE THE NOSE OF THE POLAR JET INTO THE INTERMOUNTAIN
WEST. OUTSIDE OF THE MOUNTAINS...MONDAY ACTUALLY LOOKS TO BE DRY
AND LIKELY ABOVE FREEZING IN LOWER ELEVATIONS. THE SNOWY/SIERRA
MADRE RANGES WILL BEGIN TO SEE SNOW DURING THE DAY ON MONDAY AS
THE PREVIOUSLY CUT-OFF GREAT BASIN UPPER LOW PHASES WITH THE NRN
STREAM. MOIST OROGRAPHIC FLOW WILL ENSUE AHEAD OF THIS FTR
RESULTING IN THE MOUNTAINS SNOWS. SEVERAL INCHES WILL POSSIBLE IN
THE HIER TERRAIN BY SUNSET MONDAY. 12Z MODELS PROG THE MOISTURE
TO HOLD OFF ACROSS THE PLAINS/VALLEYS UNTIL THE AFOREMENTIONED
SHORTWAVE TROUGH RIDES ATOP A SOUTH-MOVING COLD FRONT MONDAY NT.
THE INITIAL SHORTWAVE TROF SLIDES EAST FOR TUESDAY WITH A
SECONDARY SHORTWAVE MOVING INTO THE REGION PROLONGING SNOW
ACCUMULATIONS ACROSS THE AREA. THE POTENTIAL EXISTS FOR SOME
SIGNIFICANT ACCUMULATIONS LATE MONDAY INTO TUESDAY ESPECIALLY OVR
THE HIER TERRAIN. THE OTHER PART OF THIS EVENT THAT WILL HAVE
IMPACTS WILL BE THE VERY COLD TEMPERATURES THAT WILL LAST TUESDAY
AND WEDNESDAY AS 1040MB SETTLES RIGHT OVER THE AREA. MODELS PROG
-25C AT H7 IN THE CORE OF THE ARCTIC AIR MASS. THE RESULT WILL BE
FOR HIGH TEMPERATURES THAT WILL ONLY REACH THE TEENS TUE-WED WITH
LOWS TUESDAY NIGHT LIKELY NEGATIVE SINGLE DIGITS BELOW ZERO...AND
EVEN THAT IS PROBABLY BEING OPTIMISTIC. FORTUNATELY THE SNOW WILL
COME TO AN END BY LATE TUESDAY. DRY CONDITIONS AND MODERATING
TEMPERATURES RETURN THU-FRI AS FLOW FLATTENS WHILE THE PATTERN
DE-AMPLIFIES. IN FACT...EXPECT HIGH TEMPERATURES TO RETURN INTO
THE 40S BY FRIDAY. BREEZY CONDITIONS WILL ACCOMPANY THESE WARMER
TEMPERATURES ACROSS SE WYOMING THU-FRI.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 423 PM MST FRI FEB 27 2015

CONFIDENCE IS FAIRLY HIGH THAT IFR CEILINGS WILL RETURN TO KCYS
THIS EVENING AFTER SUNSET. THIS IS BACKED UP BY LATEST HRRR
GUIDANCE WHICH KEEPS IFR CONDITIONS AT KCYS THROUGH 09Z TONIGHT.
ANOTHER COLD FRONT LOOKS TO MOVE INTO THE AREA SATURDAY
MORNING...WITH NORTHEASTERLY UPSLOPING WINDS RETURNING. COULD BE
SEEING IFR CONDITIONS WITH THESE UPSLOPE WINDS...PARTICUALRLY
ACROSS THE SOUTHERN PANHANDLE AND HERE AT KCYS.

&&

.FIRE WEATHER...
ISSUED AT 353 PM MST FRI FEB 27 2015

NO CONCERNS ANTICIPATED INTO EARLY NEXT WEEK WITH COOL TO COLD
TEMPERATURES AND PERIODS OF SNOW KEEPING CONDITIONS NON-CRITICAL.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

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




000
FXUS65 KCYS 272254
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
354 PM MST FRI FEB 27 2015

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 353 PM MST FRI FEB 27 2015

CLOUDS HAVE HUNG ON ACROSS EXTREME SE WY INTO MUCH OF THE
PANHANDLE THIS AFTERNOON WITH A FEW FLURRIES NOTED AS WELL.
EXPECT GENERALLY QUIET WEATHER ACROSS THE CWA OVERNIGHT THROUGH
MUCH OF SATURDAY BUT CHILLY TEMPERATURES WILL PERSIST. A FEW
FLURRIES STILL POSSIBLE MAINLY NEAR THE COLORADO BORDER THIS
EVENING DUE TO THE UPSLOPE PATTERN INDUCED BY THE CHEYENNE RIDGE.

EXPECT TO SEE LIGHT SNOW INCREASE FROM THE SW AGAIN LATE SATURDAY
AS AN IMPULSE RIDES ENE FROM AN UPPER LOW ALONG THE CALIFORNIA
COAST AND SFC UPSLOPE STEPS UP A BIT IN RESPONSE TO AN INCREASING
SFC PRESSURE GRADIENT MAINLY ACROSS SRN WY. BETTER UPPER DYNAMICS
APPEAR THEY WILL REMAIN SOUTH OF THE CWA SO PATTERN SIMILAR TO
LAST NIGHT WHERE SNOW WILL LIKELY BE LIGHT IN NATURE WITH GROWTH
RATES NOT ALL THAT IMPRESSIVE. A GENERAL 1-3 INCHES LOOKS A DECENT
BET ACROSS THE SRN PART OF THE CWA SAT NIGHT INTO SUNDAY MORNING
BEFORE ENDING. TEMPERATURES WILL REMAIN COLD THROUGH THE WEEKEND
AS THE SFC HIGH SETTLES DOWN THE HIGH PLAINS. MAINLY DRY SUNDAY
AFTERNOON AND NIGHT AS SHORT RIDGING NOSES ACROSS THE AREA FROM
COLORADO.

.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 353 PM MST FRI FEB 27 2015

AN ENERGETIC PATTERN SHAPING UP EARLY NEXT WEEK AS A SERIES OF
SHORTWAVES RIDE THE NOSE OF THE POLAR JET INTO THE INTERMOUNTAIN
WEST. OUTSIDE OF THE MOUNTAINS...MONDAY ACTUALLY LOOKS TO BE DRY
AND LIKELY ABOVE FREEZING IN LOWER ELEVATIONS. THE SNOWY/SIERRA
MADRE RANGES WILL BEGIN TO SEE SNOW DURING THE DAY ON MONDAY AS
THE PREVIOUSLY CUT-OFF GREAT BASIN UPPER LOW PHASES WITH THE NRN
STREAM. MOIST OROGRAPHIC FLOW WILL ENSUE AHEAD OF THIS FTR
RESULTING IN THE MOUNTAINS SNOWS. SEVERAL INCHES WILL POSSIBLE IN
THE HIER TERRAIN BY SUNSET MONDAY. 12Z MODELS PROG THE MOISTURE
TO HOLD OFF ACROSS THE PLAINS/VALLEYS UNTIL THE AFOREMENTIONED
SHORTWAVE TROUGH RIDES ATOP A SOUTH-MOVING COLD FRONT MONDAY NT.
THE INITIAL SHORTWAVE TROF SLIDES EAST FOR TUESDAY WITH A
SECONDARY SHORTWAVE MOVING INTO THE REGION PROLONGING SNOW
ACCUMULATIONS ACROSS THE AREA. THE POTENTIAL EXISTS FOR SOME
SIGNIFICANT ACCUMULATIONS LATE MONDAY INTO TUESDAY ESPECIALLY OVR
THE HIER TERRAIN. THE OTHER PART OF THIS EVENT THAT WILL HAVE
IMPACTS WILL BE THE VERY COLD TEMPERATURES THAT WILL LAST TUESDAY
AND WEDNESDAY AS 1040MB SETTLES RIGHT OVER THE AREA. MODELS PROG
-25C AT H7 IN THE CORE OF THE ARCTIC AIR MASS. THE RESULT WILL BE
FOR HIGH TEMPERATURES THAT WILL ONLY REACH THE TEENS TUE-WED WITH
LOWS TUESDAY NIGHT LIKELY NEGATIVE SINGLE DIGITS BELOW ZERO...AND
EVEN THAT IS PROBABLY BEING OPTIMISTIC. FORTUNATELY THE SNOW WILL
COME TO AN END BY LATE TUESDAY. DRY CONDITIONS AND MODERATING
TEMPERATURES RETURN THU-FRI AS FLOW FLATTENS WHILE THE PATTERN
DE-AMPLIFIES. IN FACT...EXPECT HIGH TEMPERATURES TO RETURN INTO
THE 40S BY FRIDAY. BREEZY CONDITIONS WILL ACCOMPANY THESE WARMER
TEMPERATURES ACROSS SE WYOMING THU-FRI.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1106 AM MST FRI FEB 27 2015

A CHALLENGING AVIATION PERIOD SHAPING UP WITH ONGOING IFR
CIGS/VSBYS AT KCYS AND KSNY LIKELY IMPROVING BACK TO MVFR BY
19-21Z. OTHERWISE SHOULD SEE GENERALLY VFR CONDITIONS ELSEWHERE.
THE ONE TRICKY SPOT WILL BE AT KBFF WHERE CIGS WILL LIKELY BOUNCE
MVFR/VFR THRU THE AFTERNOON. WILL SEE MVFR CIGS RETURN TO
KCYS AND WRN NEBRASKA TERMINALS 00-03Z AS SOUTH/SOUTHEAST WINDS
PERSIST. WINDS WILL TURN TO WESTERLY AT KCYS BY AROUND 08Z WHICH
SHOULD ERODE LOWER CLOUDS BACK TO A VFR BKN060 LAYER. COLD FRONT
WILL BEGIN TO PUSH FROM NORTH TO SOUTH 15-18Z SATURDAY...WHICH
WILL LEAD TO ONCE AGAIN DETERIORATING CONDITIONS AND -SN CHANCES
RETURNING JUST BEYOND THE PERIOD SATURDAY AFTERNOON AND EVENING.

&&

.FIRE WEATHER...
ISSUED AT 353 PM MST FRI FEB 27 2015

NO CONCERNS ANTICIPATED INTO EARLY NEXT WEEK WITH COOL TO COLD
TEMPERATURES AND PERIODS OF SNOW KEEPING CONDITIONS NON-CRITICAL.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.

&&

$$

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




000
FXUS65 KCYS 272254
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
354 PM MST FRI FEB 27 2015

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 353 PM MST FRI FEB 27 2015

CLOUDS HAVE HUNG ON ACROSS EXTREME SE WY INTO MUCH OF THE
PANHANDLE THIS AFTERNOON WITH A FEW FLURRIES NOTED AS WELL.
EXPECT GENERALLY QUIET WEATHER ACROSS THE CWA OVERNIGHT THROUGH
MUCH OF SATURDAY BUT CHILLY TEMPERATURES WILL PERSIST. A FEW
FLURRIES STILL POSSIBLE MAINLY NEAR THE COLORADO BORDER THIS
EVENING DUE TO THE UPSLOPE PATTERN INDUCED BY THE CHEYENNE RIDGE.

EXPECT TO SEE LIGHT SNOW INCREASE FROM THE SW AGAIN LATE SATURDAY
AS AN IMPULSE RIDES ENE FROM AN UPPER LOW ALONG THE CALIFORNIA
COAST AND SFC UPSLOPE STEPS UP A BIT IN RESPONSE TO AN INCREASING
SFC PRESSURE GRADIENT MAINLY ACROSS SRN WY. BETTER UPPER DYNAMICS
APPEAR THEY WILL REMAIN SOUTH OF THE CWA SO PATTERN SIMILAR TO
LAST NIGHT WHERE SNOW WILL LIKELY BE LIGHT IN NATURE WITH GROWTH
RATES NOT ALL THAT IMPRESSIVE. A GENERAL 1-3 INCHES LOOKS A DECENT
BET ACROSS THE SRN PART OF THE CWA SAT NIGHT INTO SUNDAY MORNING
BEFORE ENDING. TEMPERATURES WILL REMAIN COLD THROUGH THE WEEKEND
AS THE SFC HIGH SETTLES DOWN THE HIGH PLAINS. MAINLY DRY SUNDAY
AFTERNOON AND NIGHT AS SHORT RIDGING NOSES ACROSS THE AREA FROM
COLORADO.

.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 353 PM MST FRI FEB 27 2015

AN ENERGETIC PATTERN SHAPING UP EARLY NEXT WEEK AS A SERIES OF
SHORTWAVES RIDE THE NOSE OF THE POLAR JET INTO THE INTERMOUNTAIN
WEST. OUTSIDE OF THE MOUNTAINS...MONDAY ACTUALLY LOOKS TO BE DRY
AND LIKELY ABOVE FREEZING IN LOWER ELEVATIONS. THE SNOWY/SIERRA
MADRE RANGES WILL BEGIN TO SEE SNOW DURING THE DAY ON MONDAY AS
THE PREVIOUSLY CUT-OFF GREAT BASIN UPPER LOW PHASES WITH THE NRN
STREAM. MOIST OROGRAPHIC FLOW WILL ENSUE AHEAD OF THIS FTR
RESULTING IN THE MOUNTAINS SNOWS. SEVERAL INCHES WILL POSSIBLE IN
THE HIER TERRAIN BY SUNSET MONDAY. 12Z MODELS PROG THE MOISTURE
TO HOLD OFF ACROSS THE PLAINS/VALLEYS UNTIL THE AFOREMENTIONED
SHORTWAVE TROUGH RIDES ATOP A SOUTH-MOVING COLD FRONT MONDAY NT.
THE INITIAL SHORTWAVE TROF SLIDES EAST FOR TUESDAY WITH A
SECONDARY SHORTWAVE MOVING INTO THE REGION PROLONGING SNOW
ACCUMULATIONS ACROSS THE AREA. THE POTENTIAL EXISTS FOR SOME
SIGNIFICANT ACCUMULATIONS LATE MONDAY INTO TUESDAY ESPECIALLY OVR
THE HIER TERRAIN. THE OTHER PART OF THIS EVENT THAT WILL HAVE
IMPACTS WILL BE THE VERY COLD TEMPERATURES THAT WILL LAST TUESDAY
AND WEDNESDAY AS 1040MB SETTLES RIGHT OVER THE AREA. MODELS PROG
-25C AT H7 IN THE CORE OF THE ARCTIC AIR MASS. THE RESULT WILL BE
FOR HIGH TEMPERATURES THAT WILL ONLY REACH THE TEENS TUE-WED WITH
LOWS TUESDAY NIGHT LIKELY NEGATIVE SINGLE DIGITS BELOW ZERO...AND
EVEN THAT IS PROBABLY BEING OPTIMISTIC. FORTUNATELY THE SNOW WILL
COME TO AN END BY LATE TUESDAY. DRY CONDITIONS AND MODERATING
TEMPERATURES RETURN THU-FRI AS FLOW FLATTENS WHILE THE PATTERN
DE-AMPLIFIES. IN FACT...EXPECT HIGH TEMPERATURES TO RETURN INTO
THE 40S BY FRIDAY. BREEZY CONDITIONS WILL ACCOMPANY THESE WARMER
TEMPERATURES ACROSS SE WYOMING THU-FRI.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1106 AM MST FRI FEB 27 2015

A CHALLENGING AVIATION PERIOD SHAPING UP WITH ONGOING IFR
CIGS/VSBYS AT KCYS AND KSNY LIKELY IMPROVING BACK TO MVFR BY
19-21Z. OTHERWISE SHOULD SEE GENERALLY VFR CONDITIONS ELSEWHERE.
THE ONE TRICKY SPOT WILL BE AT KBFF WHERE CIGS WILL LIKELY BOUNCE
MVFR/VFR THRU THE AFTERNOON. WILL SEE MVFR CIGS RETURN TO
KCYS AND WRN NEBRASKA TERMINALS 00-03Z AS SOUTH/SOUTHEAST WINDS
PERSIST. WINDS WILL TURN TO WESTERLY AT KCYS BY AROUND 08Z WHICH
SHOULD ERODE LOWER CLOUDS BACK TO A VFR BKN060 LAYER. COLD FRONT
WILL BEGIN TO PUSH FROM NORTH TO SOUTH 15-18Z SATURDAY...WHICH
WILL LEAD TO ONCE AGAIN DETERIORATING CONDITIONS AND -SN CHANCES
RETURNING JUST BEYOND THE PERIOD SATURDAY AFTERNOON AND EVENING.

&&

.FIRE WEATHER...
ISSUED AT 353 PM MST FRI FEB 27 2015

NO CONCERNS ANTICIPATED INTO EARLY NEXT WEEK WITH COOL TO COLD
TEMPERATURES AND PERIODS OF SNOW KEEPING CONDITIONS NON-CRITICAL.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.

&&

$$

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



000
FXUS65 KCYS 272254
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
354 PM MST FRI FEB 27 2015

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 353 PM MST FRI FEB 27 2015

CLOUDS HAVE HUNG ON ACROSS EXTREME SE WY INTO MUCH OF THE
PANHANDLE THIS AFTERNOON WITH A FEW FLURRIES NOTED AS WELL.
EXPECT GENERALLY QUIET WEATHER ACROSS THE CWA OVERNIGHT THROUGH
MUCH OF SATURDAY BUT CHILLY TEMPERATURES WILL PERSIST. A FEW
FLURRIES STILL POSSIBLE MAINLY NEAR THE COLORADO BORDER THIS
EVENING DUE TO THE UPSLOPE PATTERN INDUCED BY THE CHEYENNE RIDGE.

EXPECT TO SEE LIGHT SNOW INCREASE FROM THE SW AGAIN LATE SATURDAY
AS AN IMPULSE RIDES ENE FROM AN UPPER LOW ALONG THE CALIFORNIA
COAST AND SFC UPSLOPE STEPS UP A BIT IN RESPONSE TO AN INCREASING
SFC PRESSURE GRADIENT MAINLY ACROSS SRN WY. BETTER UPPER DYNAMICS
APPEAR THEY WILL REMAIN SOUTH OF THE CWA SO PATTERN SIMILAR TO
LAST NIGHT WHERE SNOW WILL LIKELY BE LIGHT IN NATURE WITH GROWTH
RATES NOT ALL THAT IMPRESSIVE. A GENERAL 1-3 INCHES LOOKS A DECENT
BET ACROSS THE SRN PART OF THE CWA SAT NIGHT INTO SUNDAY MORNING
BEFORE ENDING. TEMPERATURES WILL REMAIN COLD THROUGH THE WEEKEND
AS THE SFC HIGH SETTLES DOWN THE HIGH PLAINS. MAINLY DRY SUNDAY
AFTERNOON AND NIGHT AS SHORT RIDGING NOSES ACROSS THE AREA FROM
COLORADO.

.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 353 PM MST FRI FEB 27 2015

AN ENERGETIC PATTERN SHAPING UP EARLY NEXT WEEK AS A SERIES OF
SHORTWAVES RIDE THE NOSE OF THE POLAR JET INTO THE INTERMOUNTAIN
WEST. OUTSIDE OF THE MOUNTAINS...MONDAY ACTUALLY LOOKS TO BE DRY
AND LIKELY ABOVE FREEZING IN LOWER ELEVATIONS. THE SNOWY/SIERRA
MADRE RANGES WILL BEGIN TO SEE SNOW DURING THE DAY ON MONDAY AS
THE PREVIOUSLY CUT-OFF GREAT BASIN UPPER LOW PHASES WITH THE NRN
STREAM. MOIST OROGRAPHIC FLOW WILL ENSUE AHEAD OF THIS FTR
RESULTING IN THE MOUNTAINS SNOWS. SEVERAL INCHES WILL POSSIBLE IN
THE HIER TERRAIN BY SUNSET MONDAY. 12Z MODELS PROG THE MOISTURE
TO HOLD OFF ACROSS THE PLAINS/VALLEYS UNTIL THE AFOREMENTIONED
SHORTWAVE TROUGH RIDES ATOP A SOUTH-MOVING COLD FRONT MONDAY NT.
THE INITIAL SHORTWAVE TROF SLIDES EAST FOR TUESDAY WITH A
SECONDARY SHORTWAVE MOVING INTO THE REGION PROLONGING SNOW
ACCUMULATIONS ACROSS THE AREA. THE POTENTIAL EXISTS FOR SOME
SIGNIFICANT ACCUMULATIONS LATE MONDAY INTO TUESDAY ESPECIALLY OVR
THE HIER TERRAIN. THE OTHER PART OF THIS EVENT THAT WILL HAVE
IMPACTS WILL BE THE VERY COLD TEMPERATURES THAT WILL LAST TUESDAY
AND WEDNESDAY AS 1040MB SETTLES RIGHT OVER THE AREA. MODELS PROG
-25C AT H7 IN THE CORE OF THE ARCTIC AIR MASS. THE RESULT WILL BE
FOR HIGH TEMPERATURES THAT WILL ONLY REACH THE TEENS TUE-WED WITH
LOWS TUESDAY NIGHT LIKELY NEGATIVE SINGLE DIGITS BELOW ZERO...AND
EVEN THAT IS PROBABLY BEING OPTIMISTIC. FORTUNATELY THE SNOW WILL
COME TO AN END BY LATE TUESDAY. DRY CONDITIONS AND MODERATING
TEMPERATURES RETURN THU-FRI AS FLOW FLATTENS WHILE THE PATTERN
DE-AMPLIFIES. IN FACT...EXPECT HIGH TEMPERATURES TO RETURN INTO
THE 40S BY FRIDAY. BREEZY CONDITIONS WILL ACCOMPANY THESE WARMER
TEMPERATURES ACROSS SE WYOMING THU-FRI.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1106 AM MST FRI FEB 27 2015

A CHALLENGING AVIATION PERIOD SHAPING UP WITH ONGOING IFR
CIGS/VSBYS AT KCYS AND KSNY LIKELY IMPROVING BACK TO MVFR BY
19-21Z. OTHERWISE SHOULD SEE GENERALLY VFR CONDITIONS ELSEWHERE.
THE ONE TRICKY SPOT WILL BE AT KBFF WHERE CIGS WILL LIKELY BOUNCE
MVFR/VFR THRU THE AFTERNOON. WILL SEE MVFR CIGS RETURN TO
KCYS AND WRN NEBRASKA TERMINALS 00-03Z AS SOUTH/SOUTHEAST WINDS
PERSIST. WINDS WILL TURN TO WESTERLY AT KCYS BY AROUND 08Z WHICH
SHOULD ERODE LOWER CLOUDS BACK TO A VFR BKN060 LAYER. COLD FRONT
WILL BEGIN TO PUSH FROM NORTH TO SOUTH 15-18Z SATURDAY...WHICH
WILL LEAD TO ONCE AGAIN DETERIORATING CONDITIONS AND -SN CHANCES
RETURNING JUST BEYOND THE PERIOD SATURDAY AFTERNOON AND EVENING.

&&

.FIRE WEATHER...
ISSUED AT 353 PM MST FRI FEB 27 2015

NO CONCERNS ANTICIPATED INTO EARLY NEXT WEEK WITH COOL TO COLD
TEMPERATURES AND PERIODS OF SNOW KEEPING CONDITIONS NON-CRITICAL.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.

&&

$$

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




000
FXUS65 KCYS 272254
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
354 PM MST FRI FEB 27 2015

.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 353 PM MST FRI FEB 27 2015

CLOUDS HAVE HUNG ON ACROSS EXTREME SE WY INTO MUCH OF THE
PANHANDLE THIS AFTERNOON WITH A FEW FLURRIES NOTED AS WELL.
EXPECT GENERALLY QUIET WEATHER ACROSS THE CWA OVERNIGHT THROUGH
MUCH OF SATURDAY BUT CHILLY TEMPERATURES WILL PERSIST. A FEW
FLURRIES STILL POSSIBLE MAINLY NEAR THE COLORADO BORDER THIS
EVENING DUE TO THE UPSLOPE PATTERN INDUCED BY THE CHEYENNE RIDGE.

EXPECT TO SEE LIGHT SNOW INCREASE FROM THE SW AGAIN LATE SATURDAY
AS AN IMPULSE RIDES ENE FROM AN UPPER LOW ALONG THE CALIFORNIA
COAST AND SFC UPSLOPE STEPS UP A BIT IN RESPONSE TO AN INCREASING
SFC PRESSURE GRADIENT MAINLY ACROSS SRN WY. BETTER UPPER DYNAMICS
APPEAR THEY WILL REMAIN SOUTH OF THE CWA SO PATTERN SIMILAR TO
LAST NIGHT WHERE SNOW WILL LIKELY BE LIGHT IN NATURE WITH GROWTH
RATES NOT ALL THAT IMPRESSIVE. A GENERAL 1-3 INCHES LOOKS A DECENT
BET ACROSS THE SRN PART OF THE CWA SAT NIGHT INTO SUNDAY MORNING
BEFORE ENDING. TEMPERATURES WILL REMAIN COLD THROUGH THE WEEKEND
AS THE SFC HIGH SETTLES DOWN THE HIGH PLAINS. MAINLY DRY SUNDAY
AFTERNOON AND NIGHT AS SHORT RIDGING NOSES ACROSS THE AREA FROM
COLORADO.

.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 353 PM MST FRI FEB 27 2015

AN ENERGETIC PATTERN SHAPING UP EARLY NEXT WEEK AS A SERIES OF
SHORTWAVES RIDE THE NOSE OF THE POLAR JET INTO THE INTERMOUNTAIN
WEST. OUTSIDE OF THE MOUNTAINS...MONDAY ACTUALLY LOOKS TO BE DRY
AND LIKELY ABOVE FREEZING IN LOWER ELEVATIONS. THE SNOWY/SIERRA
MADRE RANGES WILL BEGIN TO SEE SNOW DURING THE DAY ON MONDAY AS
THE PREVIOUSLY CUT-OFF GREAT BASIN UPPER LOW PHASES WITH THE NRN
STREAM. MOIST OROGRAPHIC FLOW WILL ENSUE AHEAD OF THIS FTR
RESULTING IN THE MOUNTAINS SNOWS. SEVERAL INCHES WILL POSSIBLE IN
THE HIER TERRAIN BY SUNSET MONDAY. 12Z MODELS PROG THE MOISTURE
TO HOLD OFF ACROSS THE PLAINS/VALLEYS UNTIL THE AFOREMENTIONED
SHORTWAVE TROUGH RIDES ATOP A SOUTH-MOVING COLD FRONT MONDAY NT.
THE INITIAL SHORTWAVE TROF SLIDES EAST FOR TUESDAY WITH A
SECONDARY SHORTWAVE MOVING INTO THE REGION PROLONGING SNOW
ACCUMULATIONS ACROSS THE AREA. THE POTENTIAL EXISTS FOR SOME
SIGNIFICANT ACCUMULATIONS LATE MONDAY INTO TUESDAY ESPECIALLY OVR
THE HIER TERRAIN. THE OTHER PART OF THIS EVENT THAT WILL HAVE
IMPACTS WILL BE THE VERY COLD TEMPERATURES THAT WILL LAST TUESDAY
AND WEDNESDAY AS 1040MB SETTLES RIGHT OVER THE AREA. MODELS PROG
-25C AT H7 IN THE CORE OF THE ARCTIC AIR MASS. THE RESULT WILL BE
FOR HIGH TEMPERATURES THAT WILL ONLY REACH THE TEENS TUE-WED WITH
LOWS TUESDAY NIGHT LIKELY NEGATIVE SINGLE DIGITS BELOW ZERO...AND
EVEN THAT IS PROBABLY BEING OPTIMISTIC. FORTUNATELY THE SNOW WILL
COME TO AN END BY LATE TUESDAY. DRY CONDITIONS AND MODERATING
TEMPERATURES RETURN THU-FRI AS FLOW FLATTENS WHILE THE PATTERN
DE-AMPLIFIES. IN FACT...EXPECT HIGH TEMPERATURES TO RETURN INTO
THE 40S BY FRIDAY. BREEZY CONDITIONS WILL ACCOMPANY THESE WARMER
TEMPERATURES ACROSS SE WYOMING THU-FRI.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1106 AM MST FRI FEB 27 2015

A CHALLENGING AVIATION PERIOD SHAPING UP WITH ONGOING IFR
CIGS/VSBYS AT KCYS AND KSNY LIKELY IMPROVING BACK TO MVFR BY
19-21Z. OTHERWISE SHOULD SEE GENERALLY VFR CONDITIONS ELSEWHERE.
THE ONE TRICKY SPOT WILL BE AT KBFF WHERE CIGS WILL LIKELY BOUNCE
MVFR/VFR THRU THE AFTERNOON. WILL SEE MVFR CIGS RETURN TO
KCYS AND WRN NEBRASKA TERMINALS 00-03Z AS SOUTH/SOUTHEAST WINDS
PERSIST. WINDS WILL TURN TO WESTERLY AT KCYS BY AROUND 08Z WHICH
SHOULD ERODE LOWER CLOUDS BACK TO A VFR BKN060 LAYER. COLD FRONT
WILL BEGIN TO PUSH FROM NORTH TO SOUTH 15-18Z SATURDAY...WHICH
WILL LEAD TO ONCE AGAIN DETERIORATING CONDITIONS AND -SN CHANCES
RETURNING JUST BEYOND THE PERIOD SATURDAY AFTERNOON AND EVENING.

&&

.FIRE WEATHER...
ISSUED AT 353 PM MST FRI FEB 27 2015

NO CONCERNS ANTICIPATED INTO EARLY NEXT WEEK WITH COOL TO COLD
TEMPERATURES AND PERIODS OF SNOW KEEPING CONDITIONS NON-CRITICAL.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.

&&

$$

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


  [top]

000
FXUS65 KRIW 272200
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
300 PM MST FRI FEB 27 2015

.SHORT TERM...TONIGHT THROUGH SATURDAY

MID-AFTERNOON SATELLITE IMAGERY SHOWING AN UPPER LOW OVER THE
PACIFIC NORTHWEST WHICH WILL BE THE PRIMARY DRIVER OF OUR SENSIBLE
WEATHER THROUGH SATURDAY. ANOTHER VORTICITY CENTER WAS SPINNING EAST
ACROSS EASTERN MONTANA. THE TAIL END OF THIS SYSTEM HAS BEEN
DRAGGING ACROSS THE NORTHWEST PORTION OF THE STATE TODAY. THIS HAS
KEPT LIGHT SNOW ONGOING IN THAT CORNER WITH IR IMAGERY EVEN SHOWING
SOME ENHANCEMENT THE LAST COUPLE OF HOURS. COLDER AIR IN ASSOCIATION
WITH THIS VORTICITY LOBE IS CURRENTLY PUSHING SOUTH THROUGH CENTRAL
MONTANA. SHALLOW COLD DOME WILL BE MOVING IN TO NORTHERN WYOMING
THIS EVENING.

PACIFIC NORTHWEST UPPER LOW WILL MOVE TO THE GREAT BASIN BY SATURDAY
AFTERNOON. THIS WILL KEEP WEAK NORTHWEST FLOW ACROSS THE FORECAST
AREA WITH JUST ENOUGH EMBEDDED MOISTURE TO KEEP LIGHT SNOW GOING IN
THE NORTHWEST MOUNTAINS THROUGH TONIGHT. COLD AIR SURGE WILL BE
PUSHING THROUGH THE BIG HORN BASIN AND JOHNSON COUNTY THIS EVENING.
CLOUD COVER WILL INCREASE BEHIND THIS SURGE BUT LITTLE IS EXPECTED
IN THE WAY OF SNOW. THE COLD AIR WILL WRING OUT WHAT LITTLE MOISTURE
IT CAN...BUT RIGHT NOW HAVE AMOUNTS OF ONE INCH OR LESS. TWEAKED
TEMPERATURES FOR TONIGHT DOWN JUST A HAIR AND DID THE SAME FOR HIGH
TEMPERATURES ON SATURDAY AS SUNSHINE WILL BE LIMITED. SATURDAY
MAXIMUM TEMPERATURES WILL REMAIN WELL BELOW NORMAL...ON THE ORDER OF
15 TO 20 DEGREES...NORTH OF A LANDER TO CASPER LINE. THE SOUTHWEST
WILL BE ABOUT 5 TO 10 DEGREES BELOW NORMAL. INITIAL GUSTY NORTHERLY
WIND WILL ACCOMPANY THE SURGE OF COLD AIR...BUT PRESSURE RISES DO
NOT APPEAR TO BE THAT IMPRESSIVE. EAST-NORTHEAST WIND WILL BE
STRONGEST ACROSS EASTERN SWEETWATER COUNTY AND NEARBY AREAS. SPEEDS
IN THESE LOCATIONS WILL BE 15 TO 30 MPH. MOISTURE IN WEST-SOUTHWEST
FLOW ALOFT WILL EJECT FROM THE GREAT BASIN LOW AND TRACK TOWARD
SOUTHWEST WYOMING. EARLIER MODEL RUNS...ESPECIALLY THE NAM...HAD
GOOD 850-700MB LAYER FRONTOGENETICAL LIFT SOME POTENTIAL VORTICITY
AND JET ENERGY TO ASSIST SNOWFALL DEVELOPMENT ACROSS SWEETWATER
COUNTY. HOWEVER... NEWEST MODEL RUNS HAVE BEEN BRINGING SURFACE HIGH
FARTHER SOUTH...SO IT LOOKS LESS LIKELY THAT LIGHT SNOW WILL GET AS
FAR NORTH AS I-80 BY 00Z/SUN. TRIED TO INDICATE THIS TREND AS BEST
AS POSSIBLE DURING THE 18Z/SAT-00Z/SUN TIMEFRAME.

.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY

THERE ARE A COUPLE OF CONUNDRUMS IN THE FORECAST TODAY. THE FIRST IS
WHAT WILL HAPPEN SATURDAY NIGHT AND EARLY SUNDAY ALONG THE
INTERSTATE 80 CORRIDOR. THE MODELS CONTINUE TO BE SPLIT. THE GFS AND
THE NEW EUROPEAN SHOW THE COLD FRONT THAT WILL BE THE FOCUS FOR ANY
SNOW PUSHING FAR ENOUGH TO THE SOUTH TO KEEP THE BULK OF THE
PRECIPITATION OVER COLORADO. THE NAM KEEPS THINGS A BIT FARTHER
NORTH. HOWEVER...THE NEW 18Z NAM HAS BACKED OFF AS WELL. AT THIS
TIME...WE TRIMMED POPS AND QPF A LITTLE BUT DID NOT GO ALL THE WAY.
THE EVENING SHIFT SHOULD TAKE ANOTHER LOOK AT THIS TO SEE IF POPS
COULD BE LOWERED SOME MORE. SUNDAY SHOULD FEATURE IMPROVING
CONDITIONS AS THE FRONT SAGS SOUTHWARD OUT OF THE AREA. TEMPERATURES
WILL REMAIN RATHER COLD HOWEVER.

THE NEXT QUESTION IS FOR MONDAY AND INTO TUESDAY. THE QUESTION IS
WHAT WILL HAPPEN WITH THE COLD FRONT DROPPING SOUTHWARD OUT OF
CANADA. THE PREVIOUS SHIFT MENTIONED THAT THE SYSTEM DOES NOT LOOK
AS IMPRESSIVE AND WE AGREE. THERE CONTINUES TO BE NOT GREAT UPPER
LEVEL SUPPORT WITH THE FRONT. THERE IS A BIT OF LEFT FRONT QUAD JET
ENERGY FEEDING THE SYSTEM LATE MONDAY NIGHT INTO TUESDAY MORNING SO
AT THIS TIME THAT LOOKS TO BE THE TIME OF THE WORST CONDITIONS. THE
MODELS ARE ALSO FAIRLY CONSISTENT WITH TIMING. THIS WILL BE A FAIRLY
QUICK HITTER AS WELL WITH MOST OF THE PRECIPITATION OVER BY TUESDAY
EVENING. AND THIS LEADS TO THE NEXT QUESTION...HOW COLD WILL IT GET
TUESDAY NIGHT. THE AIR MASS MOVING INTO THE AREA WILL BE BITTERLY
COLD WITH FLOW COMING STRAIGHT OUT OF THE ARCTIC. IN ADDITION...
FRESH SNOW COVER SHOULD PROVIDE GOOD ALBEDO. 700 MILLIBAR
TEMPERATURES TUESDAY NIGHT LOOK AS COLD AS -25 C. THE WILDCARD IS
HOW MUCH THE SKY WILL CLEAR THOUGH. THE TEMPERATURES IN CONTINUITY
LOOKED REASONABLE SO WE MADE FEW CHANGES. THEY ARE STILL WELL BELOW
THE GUIDANCE WHICH IS SMART SINCE MOS USUALLY DOES A POOR JOB WITH
ARCTIC INTRUSIONS. HIGH TEMPERATURES WILL BE TRICKY FOR THE REST OF
NEXT WEEK AS WELL. WEDNESDAY LOOKS TO BE A COLD DAY DEFINITELY. SOME
MODERATION SHOULD BEGIN THURSDAY AS THE CORE OF THE ARCTIC AIR
RETREATS. THE QUESTION IS INVERSIONS IN THE BASINS AND VALLEYS. IF
IT WAS JANUARY...THEY WOULD HOLD. HOWEVER...WITH THE STRONGER MARCH
SUN THERE IS A BETTER CHANCE OF MIXING OUT. SO...FEW CHANGES WERE
MADE. AS FOR THE POTENTIAL FOR ANOTHER WEATHER MAKER FOR THE END OF
THE WEEK...THE NEW EUROPEAN HAS BACKED OFF OF THE SYSTEM WHILE THE
GFS CONTINUES TO KEEP THINGS DRY. WITH THE GFS CONTINUING TO BE MORE
CONSISTENT...WE KEPT THE FORECAST DRY WITH NEAR NORMAL TEMPERATURES.

&&

.AVIATION.../00Z ISSUANCE/

FREQUENT MOUNTAIN OBSCURATIONS WILL PERSIST ALONG AND WEST OF THE
CONTINENTAL DIVIDE THROUGH THE FORECAST PERIOD. OBSCURATIONS EAST OF
THE CONTINENTAL DIVIDE WILL BECOME MORE WIDESPREAD BEGINNING IN THE
NORTH AROUND 03Z/SAT AND CENTRAL SECTIONS FROM KLND TO KCPR BY
AROUND 09Z/SAT.

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

TERMINALS WILL BE VFR THROUGH THIS EVENING. SURGE OF COLDER AIR OVER
CENTRAL MONTANA WILL PUSH INTO THE FAR NORTHERN BIG HORN BASIN BY
03Z/SAT. LOWER CLOUD DECKS OF MVFR OR LOW VFR CEILINGS ALONG WITH
SOME VERY LIGHT SNOW WILL PUSH TO CENTRAL WYOMING BY 06Z-09Z/SAT.
THIS AIRMASS IS FAIRLY DRY SO THE SNOW THAT FALLS WILL JUST BE WRUNG
OUT FROM THE LITTLE BIT OF MOISTURE IN THIS UNSEASONABLY COLD
AIRMASS. KLND MAY BE THE BEST BET FOR A PERIOD OF REDUCED VISIBILITY
LATE TONIGHT DUE TO WEAK UPSLOPE NEAR THE WIND RIVER RANGE.
CONDITIONS MAY IMPROVE SLIGHTLY LATE SATURDAY AFTERNOON.

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

THE TAIL END OF AN UPPER LEVEL DISTURBANCE OVER NORTHEAST MONTANA
HAS KEPT LIGHT SNOW GOING ACROSS THE NORTHWEST MOUNTAINS TONIGHT.
LIMITED MOISTURE IN NORTHWEST FLOW WILL DRAG ACROSS NORTHWEST
WYOMING ON SATURDAY. TOUGH TO DISCERN WHEN THERE WOULD BE A
PROLONGED PERIOD OF MVFR IN KJAC. FOR NOW HAVE KEPT CONDITIONS
HOVERING IN THE LOW VFR RANGE THROUGH 00Z/SUN. ELSEWHERE...EXPECT
VFR CONDITIONS AT THE OTHER TERMINALS THROUGH MOST OF THE FORECAST
PERIOD. THERE IS A CHANCE FOR LIGHT SNOW TO BEGIN AROUND KRKS WITH
GUSTY EAST-NORTHEAST WIND AFTER 22Z/SAT. HOWEVER...CONFIDENCE IS NOT
THAT HIGH AND BELIEVE THE BETTER CHANCE COMES AFTER 00Z/SUN.

&&

.FIRE WEATHER...

CONTINUED NORTHWEST FLOW ALOFT WILL ALLOW FOR LIGHT SNOW SHOWERS
ACROSS NORTHWEST WYOMING TONIGHT AND SATURDAY. MOISTURE IS
LIMITED...SO AMOUNTS WILL BE LIGHT. ANOTHER SURGE OF COLDER AIR WILL
PUSH INTO THE NORTHERN BIG HORN BASIN AND JOHNSON COUNTY LATE THIS
EVENING. THIS SURGE WILL REACH CENTRAL WYOMING EARLY SATURDAY AND
SOUTHWEST WYOMING AROUND SUNRISE. EXPECT COLDER TEMPERATURES...MORE
CLOUD COVER...AND VERY LIGHT SNOW WITH THIS AIRMASS. HIGH
TEMPERATURES WILL BE 10 TO 20 DEGREES BELOW NORMAL. DRIER AIR WILL
FILTER INTO THE STATE FROM THE NORTH SATURDAY NIGHT AND SUNDAY. THIS
WILL ALLOW FOR MORE SUNSHINE AND SLIGHTLY WARMER TEMPERATURES...
ALTHOUGH IT WILL REMAIN COLDER THAN NORMAL. THE NEXT CHANCE FOR
WIDESPREAD SNOW COMES TUESDAY AND WEDNESDAY AS ANOTHER COLD SYSTEM
DROPS IN FROM THE NORTH.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...CNJ
LONG TERM...HATTINGS
AVIATION...CNJ
FIRE WEATHER...CNJ









000
FXUS65 KRIW 272200
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
300 PM MST FRI FEB 27 2015

.SHORT TERM...TONIGHT THROUGH SATURDAY

MID-AFTERNOON SATELLITE IMAGERY SHOWING AN UPPER LOW OVER THE
PACIFIC NORTHWEST WHICH WILL BE THE PRIMARY DRIVER OF OUR SENSIBLE
WEATHER THROUGH SATURDAY. ANOTHER VORTICITY CENTER WAS SPINNING EAST
ACROSS EASTERN MONTANA. THE TAIL END OF THIS SYSTEM HAS BEEN
DRAGGING ACROSS THE NORTHWEST PORTION OF THE STATE TODAY. THIS HAS
KEPT LIGHT SNOW ONGOING IN THAT CORNER WITH IR IMAGERY EVEN SHOWING
SOME ENHANCEMENT THE LAST COUPLE OF HOURS. COLDER AIR IN ASSOCIATION
WITH THIS VORTICITY LOBE IS CURRENTLY PUSHING SOUTH THROUGH CENTRAL
MONTANA. SHALLOW COLD DOME WILL BE MOVING IN TO NORTHERN WYOMING
THIS EVENING.

PACIFIC NORTHWEST UPPER LOW WILL MOVE TO THE GREAT BASIN BY SATURDAY
AFTERNOON. THIS WILL KEEP WEAK NORTHWEST FLOW ACROSS THE FORECAST
AREA WITH JUST ENOUGH EMBEDDED MOISTURE TO KEEP LIGHT SNOW GOING IN
THE NORTHWEST MOUNTAINS THROUGH TONIGHT. COLD AIR SURGE WILL BE
PUSHING THROUGH THE BIG HORN BASIN AND JOHNSON COUNTY THIS EVENING.
CLOUD COVER WILL INCREASE BEHIND THIS SURGE BUT LITTLE IS EXPECTED
IN THE WAY OF SNOW. THE COLD AIR WILL WRING OUT WHAT LITTLE MOISTURE
IT CAN...BUT RIGHT NOW HAVE AMOUNTS OF ONE INCH OR LESS. TWEAKED
TEMPERATURES FOR TONIGHT DOWN JUST A HAIR AND DID THE SAME FOR HIGH
TEMPERATURES ON SATURDAY AS SUNSHINE WILL BE LIMITED. SATURDAY
MAXIMUM TEMPERATURES WILL REMAIN WELL BELOW NORMAL...ON THE ORDER OF
15 TO 20 DEGREES...NORTH OF A LANDER TO CASPER LINE. THE SOUTHWEST
WILL BE ABOUT 5 TO 10 DEGREES BELOW NORMAL. INITIAL GUSTY NORTHERLY
WIND WILL ACCOMPANY THE SURGE OF COLD AIR...BUT PRESSURE RISES DO
NOT APPEAR TO BE THAT IMPRESSIVE. EAST-NORTHEAST WIND WILL BE
STRONGEST ACROSS EASTERN SWEETWATER COUNTY AND NEARBY AREAS. SPEEDS
IN THESE LOCATIONS WILL BE 15 TO 30 MPH. MOISTURE IN WEST-SOUTHWEST
FLOW ALOFT WILL EJECT FROM THE GREAT BASIN LOW AND TRACK TOWARD
SOUTHWEST WYOMING. EARLIER MODEL RUNS...ESPECIALLY THE NAM...HAD
GOOD 850-700MB LAYER FRONTOGENETICAL LIFT SOME POTENTIAL VORTICITY
AND JET ENERGY TO ASSIST SNOWFALL DEVELOPMENT ACROSS SWEETWATER
COUNTY. HOWEVER... NEWEST MODEL RUNS HAVE BEEN BRINGING SURFACE HIGH
FARTHER SOUTH...SO IT LOOKS LESS LIKELY THAT LIGHT SNOW WILL GET AS
FAR NORTH AS I-80 BY 00Z/SUN. TRIED TO INDICATE THIS TREND AS BEST
AS POSSIBLE DURING THE 18Z/SAT-00Z/SUN TIMEFRAME.

.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY

THERE ARE A COUPLE OF CONUNDRUMS IN THE FORECAST TODAY. THE FIRST IS
WHAT WILL HAPPEN SATURDAY NIGHT AND EARLY SUNDAY ALONG THE
INTERSTATE 80 CORRIDOR. THE MODELS CONTINUE TO BE SPLIT. THE GFS AND
THE NEW EUROPEAN SHOW THE COLD FRONT THAT WILL BE THE FOCUS FOR ANY
SNOW PUSHING FAR ENOUGH TO THE SOUTH TO KEEP THE BULK OF THE
PRECIPITATION OVER COLORADO. THE NAM KEEPS THINGS A BIT FARTHER
NORTH. HOWEVER...THE NEW 18Z NAM HAS BACKED OFF AS WELL. AT THIS
TIME...WE TRIMMED POPS AND QPF A LITTLE BUT DID NOT GO ALL THE WAY.
THE EVENING SHIFT SHOULD TAKE ANOTHER LOOK AT THIS TO SEE IF POPS
COULD BE LOWERED SOME MORE. SUNDAY SHOULD FEATURE IMPROVING
CONDITIONS AS THE FRONT SAGS SOUTHWARD OUT OF THE AREA. TEMPERATURES
WILL REMAIN RATHER COLD HOWEVER.

THE NEXT QUESTION IS FOR MONDAY AND INTO TUESDAY. THE QUESTION IS
WHAT WILL HAPPEN WITH THE COLD FRONT DROPPING SOUTHWARD OUT OF
CANADA. THE PREVIOUS SHIFT MENTIONED THAT THE SYSTEM DOES NOT LOOK
AS IMPRESSIVE AND WE AGREE. THERE CONTINUES TO BE NOT GREAT UPPER
LEVEL SUPPORT WITH THE FRONT. THERE IS A BIT OF LEFT FRONT QUAD JET
ENERGY FEEDING THE SYSTEM LATE MONDAY NIGHT INTO TUESDAY MORNING SO
AT THIS TIME THAT LOOKS TO BE THE TIME OF THE WORST CONDITIONS. THE
MODELS ARE ALSO FAIRLY CONSISTENT WITH TIMING. THIS WILL BE A FAIRLY
QUICK HITTER AS WELL WITH MOST OF THE PRECIPITATION OVER BY TUESDAY
EVENING. AND THIS LEADS TO THE NEXT QUESTION...HOW COLD WILL IT GET
TUESDAY NIGHT. THE AIR MASS MOVING INTO THE AREA WILL BE BITTERLY
COLD WITH FLOW COMING STRAIGHT OUT OF THE ARCTIC. IN ADDITION...
FRESH SNOW COVER SHOULD PROVIDE GOOD ALBEDO. 700 MILLIBAR
TEMPERATURES TUESDAY NIGHT LOOK AS COLD AS -25 C. THE WILDCARD IS
HOW MUCH THE SKY WILL CLEAR THOUGH. THE TEMPERATURES IN CONTINUITY
LOOKED REASONABLE SO WE MADE FEW CHANGES. THEY ARE STILL WELL BELOW
THE GUIDANCE WHICH IS SMART SINCE MOS USUALLY DOES A POOR JOB WITH
ARCTIC INTRUSIONS. HIGH TEMPERATURES WILL BE TRICKY FOR THE REST OF
NEXT WEEK AS WELL. WEDNESDAY LOOKS TO BE A COLD DAY DEFINITELY. SOME
MODERATION SHOULD BEGIN THURSDAY AS THE CORE OF THE ARCTIC AIR
RETREATS. THE QUESTION IS INVERSIONS IN THE BASINS AND VALLEYS. IF
IT WAS JANUARY...THEY WOULD HOLD. HOWEVER...WITH THE STRONGER MARCH
SUN THERE IS A BETTER CHANCE OF MIXING OUT. SO...FEW CHANGES WERE
MADE. AS FOR THE POTENTIAL FOR ANOTHER WEATHER MAKER FOR THE END OF
THE WEEK...THE NEW EUROPEAN HAS BACKED OFF OF THE SYSTEM WHILE THE
GFS CONTINUES TO KEEP THINGS DRY. WITH THE GFS CONTINUING TO BE MORE
CONSISTENT...WE KEPT THE FORECAST DRY WITH NEAR NORMAL TEMPERATURES.

&&

.AVIATION.../00Z ISSUANCE/

FREQUENT MOUNTAIN OBSCURATIONS WILL PERSIST ALONG AND WEST OF THE
CONTINENTAL DIVIDE THROUGH THE FORECAST PERIOD. OBSCURATIONS EAST OF
THE CONTINENTAL DIVIDE WILL BECOME MORE WIDESPREAD BEGINNING IN THE
NORTH AROUND 03Z/SAT AND CENTRAL SECTIONS FROM KLND TO KCPR BY
AROUND 09Z/SAT.

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

TERMINALS WILL BE VFR THROUGH THIS EVENING. SURGE OF COLDER AIR OVER
CENTRAL MONTANA WILL PUSH INTO THE FAR NORTHERN BIG HORN BASIN BY
03Z/SAT. LOWER CLOUD DECKS OF MVFR OR LOW VFR CEILINGS ALONG WITH
SOME VERY LIGHT SNOW WILL PUSH TO CENTRAL WYOMING BY 06Z-09Z/SAT.
THIS AIRMASS IS FAIRLY DRY SO THE SNOW THAT FALLS WILL JUST BE WRUNG
OUT FROM THE LITTLE BIT OF MOISTURE IN THIS UNSEASONABLY COLD
AIRMASS. KLND MAY BE THE BEST BET FOR A PERIOD OF REDUCED VISIBILITY
LATE TONIGHT DUE TO WEAK UPSLOPE NEAR THE WIND RIVER RANGE.
CONDITIONS MAY IMPROVE SLIGHTLY LATE SATURDAY AFTERNOON.

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

THE TAIL END OF AN UPPER LEVEL DISTURBANCE OVER NORTHEAST MONTANA
HAS KEPT LIGHT SNOW GOING ACROSS THE NORTHWEST MOUNTAINS TONIGHT.
LIMITED MOISTURE IN NORTHWEST FLOW WILL DRAG ACROSS NORTHWEST
WYOMING ON SATURDAY. TOUGH TO DISCERN WHEN THERE WOULD BE A
PROLONGED PERIOD OF MVFR IN KJAC. FOR NOW HAVE KEPT CONDITIONS
HOVERING IN THE LOW VFR RANGE THROUGH 00Z/SUN. ELSEWHERE...EXPECT
VFR CONDITIONS AT THE OTHER TERMINALS THROUGH MOST OF THE FORECAST
PERIOD. THERE IS A CHANCE FOR LIGHT SNOW TO BEGIN AROUND KRKS WITH
GUSTY EAST-NORTHEAST WIND AFTER 22Z/SAT. HOWEVER...CONFIDENCE IS NOT
THAT HIGH AND BELIEVE THE BETTER CHANCE COMES AFTER 00Z/SUN.

&&

.FIRE WEATHER...

CONTINUED NORTHWEST FLOW ALOFT WILL ALLOW FOR LIGHT SNOW SHOWERS
ACROSS NORTHWEST WYOMING TONIGHT AND SATURDAY. MOISTURE IS
LIMITED...SO AMOUNTS WILL BE LIGHT. ANOTHER SURGE OF COLDER AIR WILL
PUSH INTO THE NORTHERN BIG HORN BASIN AND JOHNSON COUNTY LATE THIS
EVENING. THIS SURGE WILL REACH CENTRAL WYOMING EARLY SATURDAY AND
SOUTHWEST WYOMING AROUND SUNRISE. EXPECT COLDER TEMPERATURES...MORE
CLOUD COVER...AND VERY LIGHT SNOW WITH THIS AIRMASS. HIGH
TEMPERATURES WILL BE 10 TO 20 DEGREES BELOW NORMAL. DRIER AIR WILL
FILTER INTO THE STATE FROM THE NORTH SATURDAY NIGHT AND SUNDAY. THIS
WILL ALLOW FOR MORE SUNSHINE AND SLIGHTLY WARMER TEMPERATURES...
ALTHOUGH IT WILL REMAIN COLDER THAN NORMAL. THE NEXT CHANCE FOR
WIDESPREAD SNOW COMES TUESDAY AND WEDNESDAY AS ANOTHER COLD SYSTEM
DROPS IN FROM THE NORTH.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...CNJ
LONG TERM...HATTINGS
AVIATION...CNJ
FIRE WEATHER...CNJ







  [top]

000
FXUS63 KUNR 272118
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
218 PM MST FRI FEB 27 2015

.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 214 PM MST FRI FEB 27 2015

BROAD UPPER TROUGH SPANS THE CONUS...WITH ARCTIC AIR PLUNGING
INTO THE SOUTHEASTERN STATES. SKIES ARE MOSTLY CLEAR OVER THE
NORTHERN PLAINS...WITH THE EXCEPTION OF FAR SOUTHWEST SD AND THE
SOUTHERN HILLS...WHERE SOME LIGHT UPSLOPE SNOW HAS BEEN REPORTED.
SURFACE HIGH TO THE SOUTHEAST OF THE REGION IS PRODUCING SOME
BREEZY SOUTHERLY WINDS ACROSS THE AREA...BRINGING IN SOME WARMER
AIR. TEMPS ARE GENERALLY IN THE 20S.

SURFACE TROUGH CROSSES THE REGION TONIGHT...CAUSING WINDS TO BECOME
NORTHWESTERLY. CLOUDS WILL INCREASE...AND MORE CHILLY AIR WILL MOVE
INTO THE REGION AS ANOTHER COLD SURFACE HIGH SLIDES IN. LOWS TONIGHT
WILL BE IN THE SINGLE DIGITS.

COLD AIR AND CLOUDS WILL CONTINUE TO ADVECT INTO THE AREA ON
SATURDAY. LOWERED HIGH TEMPS ACROSS THE NORTHWESTERN HALF OF THE CWA
FOR THESE REASONS. EXPECT HIGHS TO RANGE FROM THE UPPER TEENS ACROSS
NORTHEAST WY AND FAR NORTHWEST SD TO THE LOWER 30S ACROSS SOUTH
CENTRAL SD. UPPER FLOW BEGINS TO SPLIT SATURDAY NIGHT AS LOW CUTS
OFF OVER CA AND NORTHERNMOST ENERGY PUSHES INTO THE NORTHERN PLAINS.
THE SOUTHERN PART OF THE CWA MAY SEE SOME LIGHT SNOW ON SUNDAY NIGHT
AS THIS WAVE PASSES THROUGH...BUT KEPT CHANCES SLIGHT AS BEST
FORCING STAYS SOUTH AND HIGH PRESSURE REMAINS OVER THE AREA. SINGLE
DIGITS ARE AGAIN EXPECTED FOR LOWS SATURDAY NIGHT.

.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 214 PM MST FRI FEB 27 2015

COLD TEMPERATURES AND NORTHWESTERLY FLOW WILL CONTINUE
THROUGH SUNDAY AS AN UPPER LEVEL TROUGH MOVES OUT OF THE CWA. A
1035MB HIGH WILL SLIDE SOUTHEAST OF THE CWA DURING THE DAY SUNDAY...
GRADUALLY SWITCHING SURFACE WINDS FROM NW TO SE BY MONDAY MORNING.
MONDAY IS LOOKING TO BE MILD AS WARMER AIR ADVECTS INTO THE REGION
FROM THE WEST AHEAD OF A LONGWAVE TROUGH. THE WARMTH WILL BE SHORT
LIVED...AS AN ARCTIC FRONT WILL PUSH THROUGH THE REGION LATE MONDAY
NIGHT INTO TUESDAY MORNING. TEMPERATURES WILL DECLINE DURING THE
AFTERNOON TUESDAY AS STRONG COLD AIR ADVECTION TAKES PLACE...AND
OVERNIGHT LOWS WILL DROP BELOW ZERO FOR ALL OF THE CWA. THERE WILL
BE SOME MOISTURE BEHIND THE ARCTIC FRONT...BUT SNOW AMOUNTS WILL
GENERALLY BE LIGHT...AROUND 1 TO 3 INCHES FOR THE CWA.

THE GFS AND ECMWF ARE IN AGREEMENT OF A STRONG RIDGE BUILDING INTO
THE WESTERN US BY MIDWEEK AND PERSISTING BEYOND THE END OF THE
FORECAST PERIOD. AS A RESULT...EXPECT GENERALLY DRY CONDITIONS PAST
WEDNESDAY WITH A WARMING TREND FOR THE CWA. BY FRIDAY...AFTERNOON
HIGHS COULD BE WELL INTO THE 50S...ABOUT 10 DEGREES ABOVE
CLIMATOLOGY FOR THIS TIME OF YEAR.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING
ISSUED AT 214 PM MST FRI FEB 27 2015

AN AREA OF MVFR/NEAR-MVFR CIGS OVER SWRN SD WAS MOVING
NORTHEAST AND SPREADING INTO WCNTRL SD. SHORT-TERM GUIDANCE HAS BEEN
POOR IN HANDLING THIS...BUT GIVEN THE UPSTREAM CLOUDS/MOISTURE WOULD
EXPECT THE AREA TO CONTINUE ITS NEWD MOTION...AFFECTING WCNTRL AND
PARTS OF SCNTRL SD INTO EARLY EVNG. OTHERWISE...VFR CONDITIONS WILL
PREVAIL ACROSS THE CWA UNTIL LATE TNGT WHEN A WEAK UPPER-WAVE WILL
BRING INCREASING MVFR CIGS OVER PARTS OF NERN WY AND FAR NWRN SD.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...POJORLIE
LONG TERM...MCKEMY
AVIATION...BUNKERS







000
FXUS63 KUNR 272118
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
218 PM MST FRI FEB 27 2015

.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 214 PM MST FRI FEB 27 2015

BROAD UPPER TROUGH SPANS THE CONUS...WITH ARCTIC AIR PLUNGING
INTO THE SOUTHEASTERN STATES. SKIES ARE MOSTLY CLEAR OVER THE
NORTHERN PLAINS...WITH THE EXCEPTION OF FAR SOUTHWEST SD AND THE
SOUTHERN HILLS...WHERE SOME LIGHT UPSLOPE SNOW HAS BEEN REPORTED.
SURFACE HIGH TO THE SOUTHEAST OF THE REGION IS PRODUCING SOME
BREEZY SOUTHERLY WINDS ACROSS THE AREA...BRINGING IN SOME WARMER
AIR. TEMPS ARE GENERALLY IN THE 20S.

SURFACE TROUGH CROSSES THE REGION TONIGHT...CAUSING WINDS TO BECOME
NORTHWESTERLY. CLOUDS WILL INCREASE...AND MORE CHILLY AIR WILL MOVE
INTO THE REGION AS ANOTHER COLD SURFACE HIGH SLIDES IN. LOWS TONIGHT
WILL BE IN THE SINGLE DIGITS.

COLD AIR AND CLOUDS WILL CONTINUE TO ADVECT INTO THE AREA ON
SATURDAY. LOWERED HIGH TEMPS ACROSS THE NORTHWESTERN HALF OF THE CWA
FOR THESE REASONS. EXPECT HIGHS TO RANGE FROM THE UPPER TEENS ACROSS
NORTHEAST WY AND FAR NORTHWEST SD TO THE LOWER 30S ACROSS SOUTH
CENTRAL SD. UPPER FLOW BEGINS TO SPLIT SATURDAY NIGHT AS LOW CUTS
OFF OVER CA AND NORTHERNMOST ENERGY PUSHES INTO THE NORTHERN PLAINS.
THE SOUTHERN PART OF THE CWA MAY SEE SOME LIGHT SNOW ON SUNDAY NIGHT
AS THIS WAVE PASSES THROUGH...BUT KEPT CHANCES SLIGHT AS BEST
FORCING STAYS SOUTH AND HIGH PRESSURE REMAINS OVER THE AREA. SINGLE
DIGITS ARE AGAIN EXPECTED FOR LOWS SATURDAY NIGHT.

.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 214 PM MST FRI FEB 27 2015

COLD TEMPERATURES AND NORTHWESTERLY FLOW WILL CONTINUE
THROUGH SUNDAY AS AN UPPER LEVEL TROUGH MOVES OUT OF THE CWA. A
1035MB HIGH WILL SLIDE SOUTHEAST OF THE CWA DURING THE DAY SUNDAY...
GRADUALLY SWITCHING SURFACE WINDS FROM NW TO SE BY MONDAY MORNING.
MONDAY IS LOOKING TO BE MILD AS WARMER AIR ADVECTS INTO THE REGION
FROM THE WEST AHEAD OF A LONGWAVE TROUGH. THE WARMTH WILL BE SHORT
LIVED...AS AN ARCTIC FRONT WILL PUSH THROUGH THE REGION LATE MONDAY
NIGHT INTO TUESDAY MORNING. TEMPERATURES WILL DECLINE DURING THE
AFTERNOON TUESDAY AS STRONG COLD AIR ADVECTION TAKES PLACE...AND
OVERNIGHT LOWS WILL DROP BELOW ZERO FOR ALL OF THE CWA. THERE WILL
BE SOME MOISTURE BEHIND THE ARCTIC FRONT...BUT SNOW AMOUNTS WILL
GENERALLY BE LIGHT...AROUND 1 TO 3 INCHES FOR THE CWA.

THE GFS AND ECMWF ARE IN AGREEMENT OF A STRONG RIDGE BUILDING INTO
THE WESTERN US BY MIDWEEK AND PERSISTING BEYOND THE END OF THE
FORECAST PERIOD. AS A RESULT...EXPECT GENERALLY DRY CONDITIONS PAST
WEDNESDAY WITH A WARMING TREND FOR THE CWA. BY FRIDAY...AFTERNOON
HIGHS COULD BE WELL INTO THE 50S...ABOUT 10 DEGREES ABOVE
CLIMATOLOGY FOR THIS TIME OF YEAR.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING
ISSUED AT 214 PM MST FRI FEB 27 2015

AN AREA OF MVFR/NEAR-MVFR CIGS OVER SWRN SD WAS MOVING
NORTHEAST AND SPREADING INTO WCNTRL SD. SHORT-TERM GUIDANCE HAS BEEN
POOR IN HANDLING THIS...BUT GIVEN THE UPSTREAM CLOUDS/MOISTURE WOULD
EXPECT THE AREA TO CONTINUE ITS NEWD MOTION...AFFECTING WCNTRL AND
PARTS OF SCNTRL SD INTO EARLY EVNG. OTHERWISE...VFR CONDITIONS WILL
PREVAIL ACROSS THE CWA UNTIL LATE TNGT WHEN A WEAK UPPER-WAVE WILL
BRING INCREASING MVFR CIGS OVER PARTS OF NERN WY AND FAR NWRN SD.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...POJORLIE
LONG TERM...MCKEMY
AVIATION...BUNKERS







000
FXUS63 KUNR 272118
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
218 PM MST FRI FEB 27 2015

.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 214 PM MST FRI FEB 27 2015

BROAD UPPER TROUGH SPANS THE CONUS...WITH ARCTIC AIR PLUNGING
INTO THE SOUTHEASTERN STATES. SKIES ARE MOSTLY CLEAR OVER THE
NORTHERN PLAINS...WITH THE EXCEPTION OF FAR SOUTHWEST SD AND THE
SOUTHERN HILLS...WHERE SOME LIGHT UPSLOPE SNOW HAS BEEN REPORTED.
SURFACE HIGH TO THE SOUTHEAST OF THE REGION IS PRODUCING SOME
BREEZY SOUTHERLY WINDS ACROSS THE AREA...BRINGING IN SOME WARMER
AIR. TEMPS ARE GENERALLY IN THE 20S.

SURFACE TROUGH CROSSES THE REGION TONIGHT...CAUSING WINDS TO BECOME
NORTHWESTERLY. CLOUDS WILL INCREASE...AND MORE CHILLY AIR WILL MOVE
INTO THE REGION AS ANOTHER COLD SURFACE HIGH SLIDES IN. LOWS TONIGHT
WILL BE IN THE SINGLE DIGITS.

COLD AIR AND CLOUDS WILL CONTINUE TO ADVECT INTO THE AREA ON
SATURDAY. LOWERED HIGH TEMPS ACROSS THE NORTHWESTERN HALF OF THE CWA
FOR THESE REASONS. EXPECT HIGHS TO RANGE FROM THE UPPER TEENS ACROSS
NORTHEAST WY AND FAR NORTHWEST SD TO THE LOWER 30S ACROSS SOUTH
CENTRAL SD. UPPER FLOW BEGINS TO SPLIT SATURDAY NIGHT AS LOW CUTS
OFF OVER CA AND NORTHERNMOST ENERGY PUSHES INTO THE NORTHERN PLAINS.
THE SOUTHERN PART OF THE CWA MAY SEE SOME LIGHT SNOW ON SUNDAY NIGHT
AS THIS WAVE PASSES THROUGH...BUT KEPT CHANCES SLIGHT AS BEST
FORCING STAYS SOUTH AND HIGH PRESSURE REMAINS OVER THE AREA. SINGLE
DIGITS ARE AGAIN EXPECTED FOR LOWS SATURDAY NIGHT.

.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 214 PM MST FRI FEB 27 2015

COLD TEMPERATURES AND NORTHWESTERLY FLOW WILL CONTINUE
THROUGH SUNDAY AS AN UPPER LEVEL TROUGH MOVES OUT OF THE CWA. A
1035MB HIGH WILL SLIDE SOUTHEAST OF THE CWA DURING THE DAY SUNDAY...
GRADUALLY SWITCHING SURFACE WINDS FROM NW TO SE BY MONDAY MORNING.
MONDAY IS LOOKING TO BE MILD AS WARMER AIR ADVECTS INTO THE REGION
FROM THE WEST AHEAD OF A LONGWAVE TROUGH. THE WARMTH WILL BE SHORT
LIVED...AS AN ARCTIC FRONT WILL PUSH THROUGH THE REGION LATE MONDAY
NIGHT INTO TUESDAY MORNING. TEMPERATURES WILL DECLINE DURING THE
AFTERNOON TUESDAY AS STRONG COLD AIR ADVECTION TAKES PLACE...AND
OVERNIGHT LOWS WILL DROP BELOW ZERO FOR ALL OF THE CWA. THERE WILL
BE SOME MOISTURE BEHIND THE ARCTIC FRONT...BUT SNOW AMOUNTS WILL
GENERALLY BE LIGHT...AROUND 1 TO 3 INCHES FOR THE CWA.

THE GFS AND ECMWF ARE IN AGREEMENT OF A STRONG RIDGE BUILDING INTO
THE WESTERN US BY MIDWEEK AND PERSISTING BEYOND THE END OF THE
FORECAST PERIOD. AS A RESULT...EXPECT GENERALLY DRY CONDITIONS PAST
WEDNESDAY WITH A WARMING TREND FOR THE CWA. BY FRIDAY...AFTERNOON
HIGHS COULD BE WELL INTO THE 50S...ABOUT 10 DEGREES ABOVE
CLIMATOLOGY FOR THIS TIME OF YEAR.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING
ISSUED AT 214 PM MST FRI FEB 27 2015

AN AREA OF MVFR/NEAR-MVFR CIGS OVER SWRN SD WAS MOVING
NORTHEAST AND SPREADING INTO WCNTRL SD. SHORT-TERM GUIDANCE HAS BEEN
POOR IN HANDLING THIS...BUT GIVEN THE UPSTREAM CLOUDS/MOISTURE WOULD
EXPECT THE AREA TO CONTINUE ITS NEWD MOTION...AFFECTING WCNTRL AND
PARTS OF SCNTRL SD INTO EARLY EVNG. OTHERWISE...VFR CONDITIONS WILL
PREVAIL ACROSS THE CWA UNTIL LATE TNGT WHEN A WEAK UPPER-WAVE WILL
BRING INCREASING MVFR CIGS OVER PARTS OF NERN WY AND FAR NWRN SD.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...POJORLIE
LONG TERM...MCKEMY
AVIATION...BUNKERS







000
FXUS63 KUNR 272118
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
218 PM MST FRI FEB 27 2015

.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 214 PM MST FRI FEB 27 2015

BROAD UPPER TROUGH SPANS THE CONUS...WITH ARCTIC AIR PLUNGING
INTO THE SOUTHEASTERN STATES. SKIES ARE MOSTLY CLEAR OVER THE
NORTHERN PLAINS...WITH THE EXCEPTION OF FAR SOUTHWEST SD AND THE
SOUTHERN HILLS...WHERE SOME LIGHT UPSLOPE SNOW HAS BEEN REPORTED.
SURFACE HIGH TO THE SOUTHEAST OF THE REGION IS PRODUCING SOME
BREEZY SOUTHERLY WINDS ACROSS THE AREA...BRINGING IN SOME WARMER
AIR. TEMPS ARE GENERALLY IN THE 20S.

SURFACE TROUGH CROSSES THE REGION TONIGHT...CAUSING WINDS TO BECOME
NORTHWESTERLY. CLOUDS WILL INCREASE...AND MORE CHILLY AIR WILL MOVE
INTO THE REGION AS ANOTHER COLD SURFACE HIGH SLIDES IN. LOWS TONIGHT
WILL BE IN THE SINGLE DIGITS.

COLD AIR AND CLOUDS WILL CONTINUE TO ADVECT INTO THE AREA ON
SATURDAY. LOWERED HIGH TEMPS ACROSS THE NORTHWESTERN HALF OF THE CWA
FOR THESE REASONS. EXPECT HIGHS TO RANGE FROM THE UPPER TEENS ACROSS
NORTHEAST WY AND FAR NORTHWEST SD TO THE LOWER 30S ACROSS SOUTH
CENTRAL SD. UPPER FLOW BEGINS TO SPLIT SATURDAY NIGHT AS LOW CUTS
OFF OVER CA AND NORTHERNMOST ENERGY PUSHES INTO THE NORTHERN PLAINS.
THE SOUTHERN PART OF THE CWA MAY SEE SOME LIGHT SNOW ON SUNDAY NIGHT
AS THIS WAVE PASSES THROUGH...BUT KEPT CHANCES SLIGHT AS BEST
FORCING STAYS SOUTH AND HIGH PRESSURE REMAINS OVER THE AREA. SINGLE
DIGITS ARE AGAIN EXPECTED FOR LOWS SATURDAY NIGHT.

.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 214 PM MST FRI FEB 27 2015

COLD TEMPERATURES AND NORTHWESTERLY FLOW WILL CONTINUE
THROUGH SUNDAY AS AN UPPER LEVEL TROUGH MOVES OUT OF THE CWA. A
1035MB HIGH WILL SLIDE SOUTHEAST OF THE CWA DURING THE DAY SUNDAY...
GRADUALLY SWITCHING SURFACE WINDS FROM NW TO SE BY MONDAY MORNING.
MONDAY IS LOOKING TO BE MILD AS WARMER AIR ADVECTS INTO THE REGION
FROM THE WEST AHEAD OF A LONGWAVE TROUGH. THE WARMTH WILL BE SHORT
LIVED...AS AN ARCTIC FRONT WILL PUSH THROUGH THE REGION LATE MONDAY
NIGHT INTO TUESDAY MORNING. TEMPERATURES WILL DECLINE DURING THE
AFTERNOON TUESDAY AS STRONG COLD AIR ADVECTION TAKES PLACE...AND
OVERNIGHT LOWS WILL DROP BELOW ZERO FOR ALL OF THE CWA. THERE WILL
BE SOME MOISTURE BEHIND THE ARCTIC FRONT...BUT SNOW AMOUNTS WILL
GENERALLY BE LIGHT...AROUND 1 TO 3 INCHES FOR THE CWA.

THE GFS AND ECMWF ARE IN AGREEMENT OF A STRONG RIDGE BUILDING INTO
THE WESTERN US BY MIDWEEK AND PERSISTING BEYOND THE END OF THE
FORECAST PERIOD. AS A RESULT...EXPECT GENERALLY DRY CONDITIONS PAST
WEDNESDAY WITH A WARMING TREND FOR THE CWA. BY FRIDAY...AFTERNOON
HIGHS COULD BE WELL INTO THE 50S...ABOUT 10 DEGREES ABOVE
CLIMATOLOGY FOR THIS TIME OF YEAR.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING
ISSUED AT 214 PM MST FRI FEB 27 2015

AN AREA OF MVFR/NEAR-MVFR CIGS OVER SWRN SD WAS MOVING
NORTHEAST AND SPREADING INTO WCNTRL SD. SHORT-TERM GUIDANCE HAS BEEN
POOR IN HANDLING THIS...BUT GIVEN THE UPSTREAM CLOUDS/MOISTURE WOULD
EXPECT THE AREA TO CONTINUE ITS NEWD MOTION...AFFECTING WCNTRL AND
PARTS OF SCNTRL SD INTO EARLY EVNG. OTHERWISE...VFR CONDITIONS WILL
PREVAIL ACROSS THE CWA UNTIL LATE TNGT WHEN A WEAK UPPER-WAVE WILL
BRING INCREASING MVFR CIGS OVER PARTS OF NERN WY AND FAR NWRN SD.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...POJORLIE
LONG TERM...MCKEMY
AVIATION...BUNKERS







000
FXUS63 KUNR 272118
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
218 PM MST FRI FEB 27 2015

.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 214 PM MST FRI FEB 27 2015

BROAD UPPER TROUGH SPANS THE CONUS...WITH ARCTIC AIR PLUNGING
INTO THE SOUTHEASTERN STATES. SKIES ARE MOSTLY CLEAR OVER THE
NORTHERN PLAINS...WITH THE EXCEPTION OF FAR SOUTHWEST SD AND THE
SOUTHERN HILLS...WHERE SOME LIGHT UPSLOPE SNOW HAS BEEN REPORTED.
SURFACE HIGH TO THE SOUTHEAST OF THE REGION IS PRODUCING SOME
BREEZY SOUTHERLY WINDS ACROSS THE AREA...BRINGING IN SOME WARMER
AIR. TEMPS ARE GENERALLY IN THE 20S.

SURFACE TROUGH CROSSES THE REGION TONIGHT...CAUSING WINDS TO BECOME
NORTHWESTERLY. CLOUDS WILL INCREASE...AND MORE CHILLY AIR WILL MOVE
INTO THE REGION AS ANOTHER COLD SURFACE HIGH SLIDES IN. LOWS TONIGHT
WILL BE IN THE SINGLE DIGITS.

COLD AIR AND CLOUDS WILL CONTINUE TO ADVECT INTO THE AREA ON
SATURDAY. LOWERED HIGH TEMPS ACROSS THE NORTHWESTERN HALF OF THE CWA
FOR THESE REASONS. EXPECT HIGHS TO RANGE FROM THE UPPER TEENS ACROSS
NORTHEAST WY AND FAR NORTHWEST SD TO THE LOWER 30S ACROSS SOUTH
CENTRAL SD. UPPER FLOW BEGINS TO SPLIT SATURDAY NIGHT AS LOW CUTS
OFF OVER CA AND NORTHERNMOST ENERGY PUSHES INTO THE NORTHERN PLAINS.
THE SOUTHERN PART OF THE CWA MAY SEE SOME LIGHT SNOW ON SUNDAY NIGHT
AS THIS WAVE PASSES THROUGH...BUT KEPT CHANCES SLIGHT AS BEST
FORCING STAYS SOUTH AND HIGH PRESSURE REMAINS OVER THE AREA. SINGLE
DIGITS ARE AGAIN EXPECTED FOR LOWS SATURDAY NIGHT.

.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 214 PM MST FRI FEB 27 2015

COLD TEMPERATURES AND NORTHWESTERLY FLOW WILL CONTINUE
THROUGH SUNDAY AS AN UPPER LEVEL TROUGH MOVES OUT OF THE CWA. A
1035MB HIGH WILL SLIDE SOUTHEAST OF THE CWA DURING THE DAY SUNDAY...
GRADUALLY SWITCHING SURFACE WINDS FROM NW TO SE BY MONDAY MORNING.
MONDAY IS LOOKING TO BE MILD AS WARMER AIR ADVECTS INTO THE REGION
FROM THE WEST AHEAD OF A LONGWAVE TROUGH. THE WARMTH WILL BE SHORT
LIVED...AS AN ARCTIC FRONT WILL PUSH THROUGH THE REGION LATE MONDAY
NIGHT INTO TUESDAY MORNING. TEMPERATURES WILL DECLINE DURING THE
AFTERNOON TUESDAY AS STRONG COLD AIR ADVECTION TAKES PLACE...AND
OVERNIGHT LOWS WILL DROP BELOW ZERO FOR ALL OF THE CWA. THERE WILL
BE SOME MOISTURE BEHIND THE ARCTIC FRONT...BUT SNOW AMOUNTS WILL
GENERALLY BE LIGHT...AROUND 1 TO 3 INCHES FOR THE CWA.

THE GFS AND ECMWF ARE IN AGREEMENT OF A STRONG RIDGE BUILDING INTO
THE WESTERN US BY MIDWEEK AND PERSISTING BEYOND THE END OF THE
FORECAST PERIOD. AS A RESULT...EXPECT GENERALLY DRY CONDITIONS PAST
WEDNESDAY WITH A WARMING TREND FOR THE CWA. BY FRIDAY...AFTERNOON
HIGHS COULD BE WELL INTO THE 50S...ABOUT 10 DEGREES ABOVE
CLIMATOLOGY FOR THIS TIME OF YEAR.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING
ISSUED AT 214 PM MST FRI FEB 27 2015

AN AREA OF MVFR/NEAR-MVFR CIGS OVER SWRN SD WAS MOVING
NORTHEAST AND SPREADING INTO WCNTRL SD. SHORT-TERM GUIDANCE HAS BEEN
POOR IN HANDLING THIS...BUT GIVEN THE UPSTREAM CLOUDS/MOISTURE WOULD
EXPECT THE AREA TO CONTINUE ITS NEWD MOTION...AFFECTING WCNTRL AND
PARTS OF SCNTRL SD INTO EARLY EVNG. OTHERWISE...VFR CONDITIONS WILL
PREVAIL ACROSS THE CWA UNTIL LATE TNGT WHEN A WEAK UPPER-WAVE WILL
BRING INCREASING MVFR CIGS OVER PARTS OF NERN WY AND FAR NWRN SD.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...POJORLIE
LONG TERM...MCKEMY
AVIATION...BUNKERS







000
FXUS63 KUNR 272118
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
218 PM MST FRI FEB 27 2015

.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 214 PM MST FRI FEB 27 2015

BROAD UPPER TROUGH SPANS THE CONUS...WITH ARCTIC AIR PLUNGING
INTO THE SOUTHEASTERN STATES. SKIES ARE MOSTLY CLEAR OVER THE
NORTHERN PLAINS...WITH THE EXCEPTION OF FAR SOUTHWEST SD AND THE
SOUTHERN HILLS...WHERE SOME LIGHT UPSLOPE SNOW HAS BEEN REPORTED.
SURFACE HIGH TO THE SOUTHEAST OF THE REGION IS PRODUCING SOME
BREEZY SOUTHERLY WINDS ACROSS THE AREA...BRINGING IN SOME WARMER
AIR. TEMPS ARE GENERALLY IN THE 20S.

SURFACE TROUGH CROSSES THE REGION TONIGHT...CAUSING WINDS TO BECOME
NORTHWESTERLY. CLOUDS WILL INCREASE...AND MORE CHILLY AIR WILL MOVE
INTO THE REGION AS ANOTHER COLD SURFACE HIGH SLIDES IN. LOWS TONIGHT
WILL BE IN THE SINGLE DIGITS.

COLD AIR AND CLOUDS WILL CONTINUE TO ADVECT INTO THE AREA ON
SATURDAY. LOWERED HIGH TEMPS ACROSS THE NORTHWESTERN HALF OF THE CWA
FOR THESE REASONS. EXPECT HIGHS TO RANGE FROM THE UPPER TEENS ACROSS
NORTHEAST WY AND FAR NORTHWEST SD TO THE LOWER 30S ACROSS SOUTH
CENTRAL SD. UPPER FLOW BEGINS TO SPLIT SATURDAY NIGHT AS LOW CUTS
OFF OVER CA AND NORTHERNMOST ENERGY PUSHES INTO THE NORTHERN PLAINS.
THE SOUTHERN PART OF THE CWA MAY SEE SOME LIGHT SNOW ON SUNDAY NIGHT
AS THIS WAVE PASSES THROUGH...BUT KEPT CHANCES SLIGHT AS BEST
FORCING STAYS SOUTH AND HIGH PRESSURE REMAINS OVER THE AREA. SINGLE
DIGITS ARE AGAIN EXPECTED FOR LOWS SATURDAY NIGHT.

.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 214 PM MST FRI FEB 27 2015

COLD TEMPERATURES AND NORTHWESTERLY FLOW WILL CONTINUE
THROUGH SUNDAY AS AN UPPER LEVEL TROUGH MOVES OUT OF THE CWA. A
1035MB HIGH WILL SLIDE SOUTHEAST OF THE CWA DURING THE DAY SUNDAY...
GRADUALLY SWITCHING SURFACE WINDS FROM NW TO SE BY MONDAY MORNING.
MONDAY IS LOOKING TO BE MILD AS WARMER AIR ADVECTS INTO THE REGION
FROM THE WEST AHEAD OF A LONGWAVE TROUGH. THE WARMTH WILL BE SHORT
LIVED...AS AN ARCTIC FRONT WILL PUSH THROUGH THE REGION LATE MONDAY
NIGHT INTO TUESDAY MORNING. TEMPERATURES WILL DECLINE DURING THE
AFTERNOON TUESDAY AS STRONG COLD AIR ADVECTION TAKES PLACE...AND
OVERNIGHT LOWS WILL DROP BELOW ZERO FOR ALL OF THE CWA. THERE WILL
BE SOME MOISTURE BEHIND THE ARCTIC FRONT...BUT SNOW AMOUNTS WILL
GENERALLY BE LIGHT...AROUND 1 TO 3 INCHES FOR THE CWA.

THE GFS AND ECMWF ARE IN AGREEMENT OF A STRONG RIDGE BUILDING INTO
THE WESTERN US BY MIDWEEK AND PERSISTING BEYOND THE END OF THE
FORECAST PERIOD. AS A RESULT...EXPECT GENERALLY DRY CONDITIONS PAST
WEDNESDAY WITH A WARMING TREND FOR THE CWA. BY FRIDAY...AFTERNOON
HIGHS COULD BE WELL INTO THE 50S...ABOUT 10 DEGREES ABOVE
CLIMATOLOGY FOR THIS TIME OF YEAR.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING
ISSUED AT 214 PM MST FRI FEB 27 2015

AN AREA OF MVFR/NEAR-MVFR CIGS OVER SWRN SD WAS MOVING
NORTHEAST AND SPREADING INTO WCNTRL SD. SHORT-TERM GUIDANCE HAS BEEN
POOR IN HANDLING THIS...BUT GIVEN THE UPSTREAM CLOUDS/MOISTURE WOULD
EXPECT THE AREA TO CONTINUE ITS NEWD MOTION...AFFECTING WCNTRL AND
PARTS OF SCNTRL SD INTO EARLY EVNG. OTHERWISE...VFR CONDITIONS WILL
PREVAIL ACROSS THE CWA UNTIL LATE TNGT WHEN A WEAK UPPER-WAVE WILL
BRING INCREASING MVFR CIGS OVER PARTS OF NERN WY AND FAR NWRN SD.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...POJORLIE
LONG TERM...MCKEMY
AVIATION...BUNKERS







000
FXUS63 KUNR 272118
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
218 PM MST FRI FEB 27 2015

.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 214 PM MST FRI FEB 27 2015

BROAD UPPER TROUGH SPANS THE CONUS...WITH ARCTIC AIR PLUNGING
INTO THE SOUTHEASTERN STATES. SKIES ARE MOSTLY CLEAR OVER THE
NORTHERN PLAINS...WITH THE EXCEPTION OF FAR SOUTHWEST SD AND THE
SOUTHERN HILLS...WHERE SOME LIGHT UPSLOPE SNOW HAS BEEN REPORTED.
SURFACE HIGH TO THE SOUTHEAST OF THE REGION IS PRODUCING SOME
BREEZY SOUTHERLY WINDS ACROSS THE AREA...BRINGING IN SOME WARMER
AIR. TEMPS ARE GENERALLY IN THE 20S.

SURFACE TROUGH CROSSES THE REGION TONIGHT...CAUSING WINDS TO BECOME
NORTHWESTERLY. CLOUDS WILL INCREASE...AND MORE CHILLY AIR WILL MOVE
INTO THE REGION AS ANOTHER COLD SURFACE HIGH SLIDES IN. LOWS TONIGHT
WILL BE IN THE SINGLE DIGITS.

COLD AIR AND CLOUDS WILL CONTINUE TO ADVECT INTO THE AREA ON
SATURDAY. LOWERED HIGH TEMPS ACROSS THE NORTHWESTERN HALF OF THE CWA
FOR THESE REASONS. EXPECT HIGHS TO RANGE FROM THE UPPER TEENS ACROSS
NORTHEAST WY AND FAR NORTHWEST SD TO THE LOWER 30S ACROSS SOUTH
CENTRAL SD. UPPER FLOW BEGINS TO SPLIT SATURDAY NIGHT AS LOW CUTS
OFF OVER CA AND NORTHERNMOST ENERGY PUSHES INTO THE NORTHERN PLAINS.
THE SOUTHERN PART OF THE CWA MAY SEE SOME LIGHT SNOW ON SUNDAY NIGHT
AS THIS WAVE PASSES THROUGH...BUT KEPT CHANCES SLIGHT AS BEST
FORCING STAYS SOUTH AND HIGH PRESSURE REMAINS OVER THE AREA. SINGLE
DIGITS ARE AGAIN EXPECTED FOR LOWS SATURDAY NIGHT.

.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 214 PM MST FRI FEB 27 2015

COLD TEMPERATURES AND NORTHWESTERLY FLOW WILL CONTINUE
THROUGH SUNDAY AS AN UPPER LEVEL TROUGH MOVES OUT OF THE CWA. A
1035MB HIGH WILL SLIDE SOUTHEAST OF THE CWA DURING THE DAY SUNDAY...
GRADUALLY SWITCHING SURFACE WINDS FROM NW TO SE BY MONDAY MORNING.
MONDAY IS LOOKING TO BE MILD AS WARMER AIR ADVECTS INTO THE REGION
FROM THE WEST AHEAD OF A LONGWAVE TROUGH. THE WARMTH WILL BE SHORT
LIVED...AS AN ARCTIC FRONT WILL PUSH THROUGH THE REGION LATE MONDAY
NIGHT INTO TUESDAY MORNING. TEMPERATURES WILL DECLINE DURING THE
AFTERNOON TUESDAY AS STRONG COLD AIR ADVECTION TAKES PLACE...AND
OVERNIGHT LOWS WILL DROP BELOW ZERO FOR ALL OF THE CWA. THERE WILL
BE SOME MOISTURE BEHIND THE ARCTIC FRONT...BUT SNOW AMOUNTS WILL
GENERALLY BE LIGHT...AROUND 1 TO 3 INCHES FOR THE CWA.

THE GFS AND ECMWF ARE IN AGREEMENT OF A STRONG RIDGE BUILDING INTO
THE WESTERN US BY MIDWEEK AND PERSISTING BEYOND THE END OF THE
FORECAST PERIOD. AS A RESULT...EXPECT GENERALLY DRY CONDITIONS PAST
WEDNESDAY WITH A WARMING TREND FOR THE CWA. BY FRIDAY...AFTERNOON
HIGHS COULD BE WELL INTO THE 50S...ABOUT 10 DEGREES ABOVE
CLIMATOLOGY FOR THIS TIME OF YEAR.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING
ISSUED AT 214 PM MST FRI FEB 27 2015

AN AREA OF MVFR/NEAR-MVFR CIGS OVER SWRN SD WAS MOVING
NORTHEAST AND SPREADING INTO WCNTRL SD. SHORT-TERM GUIDANCE HAS BEEN
POOR IN HANDLING THIS...BUT GIVEN THE UPSTREAM CLOUDS/MOISTURE WOULD
EXPECT THE AREA TO CONTINUE ITS NEWD MOTION...AFFECTING WCNTRL AND
PARTS OF SCNTRL SD INTO EARLY EVNG. OTHERWISE...VFR CONDITIONS WILL
PREVAIL ACROSS THE CWA UNTIL LATE TNGT WHEN A WEAK UPPER-WAVE WILL
BRING INCREASING MVFR CIGS OVER PARTS OF NERN WY AND FAR NWRN SD.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...POJORLIE
LONG TERM...MCKEMY
AVIATION...BUNKERS







000
FXUS63 KUNR 272118
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
218 PM MST FRI FEB 27 2015

.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 214 PM MST FRI FEB 27 2015

BROAD UPPER TROUGH SPANS THE CONUS...WITH ARCTIC AIR PLUNGING
INTO THE SOUTHEASTERN STATES. SKIES ARE MOSTLY CLEAR OVER THE
NORTHERN PLAINS...WITH THE EXCEPTION OF FAR SOUTHWEST SD AND THE
SOUTHERN HILLS...WHERE SOME LIGHT UPSLOPE SNOW HAS BEEN REPORTED.
SURFACE HIGH TO THE SOUTHEAST OF THE REGION IS PRODUCING SOME
BREEZY SOUTHERLY WINDS ACROSS THE AREA...BRINGING IN SOME WARMER
AIR. TEMPS ARE GENERALLY IN THE 20S.

SURFACE TROUGH CROSSES THE REGION TONIGHT...CAUSING WINDS TO BECOME
NORTHWESTERLY. CLOUDS WILL INCREASE...AND MORE CHILLY AIR WILL MOVE
INTO THE REGION AS ANOTHER COLD SURFACE HIGH SLIDES IN. LOWS TONIGHT
WILL BE IN THE SINGLE DIGITS.

COLD AIR AND CLOUDS WILL CONTINUE TO ADVECT INTO THE AREA ON
SATURDAY. LOWERED HIGH TEMPS ACROSS THE NORTHWESTERN HALF OF THE CWA
FOR THESE REASONS. EXPECT HIGHS TO RANGE FROM THE UPPER TEENS ACROSS
NORTHEAST WY AND FAR NORTHWEST SD TO THE LOWER 30S ACROSS SOUTH
CENTRAL SD. UPPER FLOW BEGINS TO SPLIT SATURDAY NIGHT AS LOW CUTS
OFF OVER CA AND NORTHERNMOST ENERGY PUSHES INTO THE NORTHERN PLAINS.
THE SOUTHERN PART OF THE CWA MAY SEE SOME LIGHT SNOW ON SUNDAY NIGHT
AS THIS WAVE PASSES THROUGH...BUT KEPT CHANCES SLIGHT AS BEST
FORCING STAYS SOUTH AND HIGH PRESSURE REMAINS OVER THE AREA. SINGLE
DIGITS ARE AGAIN EXPECTED FOR LOWS SATURDAY NIGHT.

.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 214 PM MST FRI FEB 27 2015

COLD TEMPERATURES AND NORTHWESTERLY FLOW WILL CONTINUE
THROUGH SUNDAY AS AN UPPER LEVEL TROUGH MOVES OUT OF THE CWA. A
1035MB HIGH WILL SLIDE SOUTHEAST OF THE CWA DURING THE DAY SUNDAY...
GRADUALLY SWITCHING SURFACE WINDS FROM NW TO SE BY MONDAY MORNING.
MONDAY IS LOOKING TO BE MILD AS WARMER AIR ADVECTS INTO THE REGION
FROM THE WEST AHEAD OF A LONGWAVE TROUGH. THE WARMTH WILL BE SHORT
LIVED...AS AN ARCTIC FRONT WILL PUSH THROUGH THE REGION LATE MONDAY
NIGHT INTO TUESDAY MORNING. TEMPERATURES WILL DECLINE DURING THE
AFTERNOON TUESDAY AS STRONG COLD AIR ADVECTION TAKES PLACE...AND
OVERNIGHT LOWS WILL DROP BELOW ZERO FOR ALL OF THE CWA. THERE WILL
BE SOME MOISTURE BEHIND THE ARCTIC FRONT...BUT SNOW AMOUNTS WILL
GENERALLY BE LIGHT...AROUND 1 TO 3 INCHES FOR THE CWA.

THE GFS AND ECMWF ARE IN AGREEMENT OF A STRONG RIDGE BUILDING INTO
THE WESTERN US BY MIDWEEK AND PERSISTING BEYOND THE END OF THE
FORECAST PERIOD. AS A RESULT...EXPECT GENERALLY DRY CONDITIONS PAST
WEDNESDAY WITH A WARMING TREND FOR THE CWA. BY FRIDAY...AFTERNOON
HIGHS COULD BE WELL INTO THE 50S...ABOUT 10 DEGREES ABOVE
CLIMATOLOGY FOR THIS TIME OF YEAR.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING
ISSUED AT 214 PM MST FRI FEB 27 2015

AN AREA OF MVFR/NEAR-MVFR CIGS OVER SWRN SD WAS MOVING
NORTHEAST AND SPREADING INTO WCNTRL SD. SHORT-TERM GUIDANCE HAS BEEN
POOR IN HANDLING THIS...BUT GIVEN THE UPSTREAM CLOUDS/MOISTURE WOULD
EXPECT THE AREA TO CONTINUE ITS NEWD MOTION...AFFECTING WCNTRL AND
PARTS OF SCNTRL SD INTO EARLY EVNG. OTHERWISE...VFR CONDITIONS WILL
PREVAIL ACROSS THE CWA UNTIL LATE TNGT WHEN A WEAK UPPER-WAVE WILL
BRING INCREASING MVFR CIGS OVER PARTS OF NERN WY AND FAR NWRN SD.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...POJORLIE
LONG TERM...MCKEMY
AVIATION...BUNKERS







000
FXUS65 KCYS 271806
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1106 AM MST FRI FEB 27 2015

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 330 AM MST FRI FEB 27 2015

RADAR IMAGERY SHOWS LIGHT SNOW HAS REALLY LET UP ACROSS LARAMIE
COUNTY WITH ONLY VERY LIGHT SNOW OR FLURRIES. CANCELLED THE WINTER
WEATHER ADVISORY A BIT EARLY WITH MINIMAL ADDITIONAL ACCUMULATION
EXPECTED. COLD WIND CHILLS HAVE BEEN OCCURRING OVER THE SOUTHERN
LARAMIE RANGE WITH VALUES IN THE -20 TO -25 RANGE. WITH NOT MUCH
CHANGE IN THE TEMPS OR WINDS THROUGH SUNRISE...SEE NO REASON THAT
WIND CHILLS WILL REACH WARNING CRITERIA(-30)...HOWEVER WILL CONTINUE
TO MONITOR. SOUTHERLY WINDS WILL PERSIST THROUGH THE AFTN ACROSS
THE PLAINS WITH LOW LEVEL UPSLOPE ALONG THE CHEYENNE RIDGE. ALL
MODELS SHOW LOW CLOUDS BEING QUITE PERSISTENT ALONG THE CHEYENNE
RIDGE AND INTO THE SOUTHERN PANHANDLE THROUGH THE EARLY AFTN WHICH
WILL KEEP TEMPS FROM WARMING TOO MUCH COMPARED TO YESTERDAY. OTHER
AREAS WHERE CLEARING OCCURS WILL WARM 5-10 DEGREES...BUT THAT
STILL PUTS US AROUND 20 DEGREES BELOW NORMAL FOR LATE FEB. PRETTY
QUIET WEATHER FROM THIS EVENING THROUGH MIDDAY SATURDAY. WINDS
WILL BE WEAK AND RADIATIONAL COOLING WILL BE BETTER TONIGHT WITH
LESS LOW CLOUDS PRESENT...SO LOWS WILL ONCE AGAIN FALL INTO THE
SINGLE DIGITS.

ANOTHER LIGHT SNOW EVENT APPEARS POSSIBLE FROM MAINLY SAT AFTN
THROUGH SAT NIGHT. THE 00Z EURO HOWEVER CONTINUES TO BE THE OUTLIER
IN SHOWING ALMOST ALL THE QPF TO THE SOUTH OF THE COLORADO BORDER.
THE NAM HAS COME MORE IN LINE WITH THE CONSISTENTLY WETTER GFS...
SHOWING WIDESPREAD 0.1-0.2 INCHES OVER MUCH OF THE CWA. WITH LOW
LEVEL UPSLOPE AND ISENTROPIC LIFT BEING THE PRIMARY FORCING
MECHANISMS... STILL BELIEVE THAT MOST LOCATIONS WILL ONLY PICK UP
A FEW INCHES AND BEING LARGELY SUB-ADVISORY. WITH WINDS LARGELY
REMAINING BELOW 15 KTS...AREAS OF BLOWING SNOW WILL NOT BE A
CONCERN. PRECIP COMES TO AN END BY LATE SUN MORNING WITH ANOTHER
CHILLY DAY IN STORE.

.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 AM MST FRI FEB 27 2015

00Z MEDIUM RANGE MODELS ARE IN GOOD AGREEMENT PORTRAYING A SPLIT
FLOW ALOFT WITH A MORE PROGRESSIVE NORTHERN STREAM AND SLOWER
SOUTHERN STREAM. WEST-SOUTHWEST FLOW ALOFT AHEAD OF CA/NV TROUGH
WILL ADVECT ABUNDANT PACIFIC MOISTURE ACROSS THE FOUR CORNERS AND
CENTRAL ROCKIES EARLY NEXT WEEK. POTENT NORTHERN STREAM SHORTWAVE
MOVING ACROSS THE NORTHERN ROCKIES WILL PROPEL A ARCTIC COLD FRONT
SOUTHEAST ACROSS THE CWA BY TUESDAY MORNING. PRIOR TO THE FROPA...
A SURFACE LOW OVER THE FOUR CORNERS TRACKS NORTHEAST TO EAST
THROUGH SOUTHERN COLORADO AND KANSAS. POST-FRONTAL UPSLOPE NORTHEAST
LOW LEVEL FLOW...Q-G LIFT FROM RIGHT REAR QUAD OF UPPER JET AND
OVERRUNNING MOISTURE ACROSS A SHALLOW COLD AIR MASS WILL SET THE
STAGE FOR WIDESPREAD ACCUMULATING SNOW TUESDAY. GUSTY NORTH-NORTHEAST
WINDS WILL CREATE AREAS OF BLOWING/DRIFTING SNOW. IT`S EARLY TO
FORECAST SNOW AMOUNTS...BUT THIS SYSTEM WILL BE PROGRESSIVE WITH
SNOW TAPERING OFF FROM NORTHWEST TO SOUTHEAST TUESDAY NIGHT AS
COLD HIGH PRESSURE BUILDS ACROSS THE REGION. TEMPERATURES WILL BE
MILDER AHEAD OF THE FRONT MONDAY BUT AT LEAST 1O DEGREES BELOW
NORMAL. MUCH COLDER TEMPERATURES RETURN TUESDAY AND LAST THROUGH
MIDWEEK WITH HIGHS IN THE TEENS AND LOWS FROM 10 BELOW TO 10 ABOVE
ZERO. IN THE WAKE OF THE MIDWEEK SYSTEM...FLOW ALOFT BACKS FROM
NORTH- NORTHWEST TO MORE ZONAL THURSDAY. WESTERLY 700MB WINDS
PICK UP TO 40 KT THURSDAY RESULTING IN GUSTY DOWNSLOPE WINDS LEE
OF THE FRONT RANGE PUSHING THE MERCURY INTO THE 30S.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1106 AM MST FRI FEB 27 2015

A CHALLENGING AVIATION PERIOD SHAPING UP WITH ONGOING IFR
CIGS/VSBYS AT KCYS AND KSNY LIKELY IMPROVING BACK TO MVFR BY
19-21Z. OTHERWISE SHOULD SEE GENERALLY VFR CONDITIONS ELSEWHERE.
THE ONE TRICKY SPOT WILL BE AT KBFF WHERE CIGS WILL LIKELY BOUNCE
MVFR/VFR THRU THE AFTERNOON. WILL SEE MVFR CIGS RETURN TO
KCYS AND WRN NEBRASKA TERMINALS 00-03Z AS SOUTH/SOUTHEAST WINDS
PERSIST. WINDS WILL TURN TO WESTERLY AT KCYS BY AROUND 08Z WHICH
SHOULD ERODE LOWER CLOUDS BACK TO A VFR BKN060 LAYER. COLD FRONT
WILL BEGIN TO PUSH FROM NORTH TO SOUTH 15-18Z SATURDAY...WHICH
WILL LEAD TO ONCE AGAIN DETERIORATING CONDITIONS AND -SN CHANCES
RETURNING JUST BEYOND THE PERIOD SATURDAY AFTERNOON AND EVENING.

&&

.FIRE WEATHER...
ISSUED AT 245 AM MST FRI FEB 27 2015

NO FIRE WEATHER CONCERNS OVER THE NEXT WEEK. TEMPERATURES WILL
CONTINUE TO REMAIN BELOW NORMAL. WIDESPREAD LIGHT SNOW COULD FALL
SATURDAY AFTERNOON THROUGH THE NIGHT...ESPECIALLY FOR AREAS ALONG
THE COLORADO BORDER.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

SHORT TERM...FINCH
LONG TERM...JAMSKI
AVIATION...CAH
FIRE WEATHER...FINCH



000
FXUS65 KCYS 271806
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1106 AM MST FRI FEB 27 2015

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 330 AM MST FRI FEB 27 2015

RADAR IMAGERY SHOWS LIGHT SNOW HAS REALLY LET UP ACROSS LARAMIE
COUNTY WITH ONLY VERY LIGHT SNOW OR FLURRIES. CANCELLED THE WINTER
WEATHER ADVISORY A BIT EARLY WITH MINIMAL ADDITIONAL ACCUMULATION
EXPECTED. COLD WIND CHILLS HAVE BEEN OCCURRING OVER THE SOUTHERN
LARAMIE RANGE WITH VALUES IN THE -20 TO -25 RANGE. WITH NOT MUCH
CHANGE IN THE TEMPS OR WINDS THROUGH SUNRISE...SEE NO REASON THAT
WIND CHILLS WILL REACH WARNING CRITERIA(-30)...HOWEVER WILL CONTINUE
TO MONITOR. SOUTHERLY WINDS WILL PERSIST THROUGH THE AFTN ACROSS
THE PLAINS WITH LOW LEVEL UPSLOPE ALONG THE CHEYENNE RIDGE. ALL
MODELS SHOW LOW CLOUDS BEING QUITE PERSISTENT ALONG THE CHEYENNE
RIDGE AND INTO THE SOUTHERN PANHANDLE THROUGH THE EARLY AFTN WHICH
WILL KEEP TEMPS FROM WARMING TOO MUCH COMPARED TO YESTERDAY. OTHER
AREAS WHERE CLEARING OCCURS WILL WARM 5-10 DEGREES...BUT THAT
STILL PUTS US AROUND 20 DEGREES BELOW NORMAL FOR LATE FEB. PRETTY
QUIET WEATHER FROM THIS EVENING THROUGH MIDDAY SATURDAY. WINDS
WILL BE WEAK AND RADIATIONAL COOLING WILL BE BETTER TONIGHT WITH
LESS LOW CLOUDS PRESENT...SO LOWS WILL ONCE AGAIN FALL INTO THE
SINGLE DIGITS.

ANOTHER LIGHT SNOW EVENT APPEARS POSSIBLE FROM MAINLY SAT AFTN
THROUGH SAT NIGHT. THE 00Z EURO HOWEVER CONTINUES TO BE THE OUTLIER
IN SHOWING ALMOST ALL THE QPF TO THE SOUTH OF THE COLORADO BORDER.
THE NAM HAS COME MORE IN LINE WITH THE CONSISTENTLY WETTER GFS...
SHOWING WIDESPREAD 0.1-0.2 INCHES OVER MUCH OF THE CWA. WITH LOW
LEVEL UPSLOPE AND ISENTROPIC LIFT BEING THE PRIMARY FORCING
MECHANISMS... STILL BELIEVE THAT MOST LOCATIONS WILL ONLY PICK UP
A FEW INCHES AND BEING LARGELY SUB-ADVISORY. WITH WINDS LARGELY
REMAINING BELOW 15 KTS...AREAS OF BLOWING SNOW WILL NOT BE A
CONCERN. PRECIP COMES TO AN END BY LATE SUN MORNING WITH ANOTHER
CHILLY DAY IN STORE.

.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 AM MST FRI FEB 27 2015

00Z MEDIUM RANGE MODELS ARE IN GOOD AGREEMENT PORTRAYING A SPLIT
FLOW ALOFT WITH A MORE PROGRESSIVE NORTHERN STREAM AND SLOWER
SOUTHERN STREAM. WEST-SOUTHWEST FLOW ALOFT AHEAD OF CA/NV TROUGH
WILL ADVECT ABUNDANT PACIFIC MOISTURE ACROSS THE FOUR CORNERS AND
CENTRAL ROCKIES EARLY NEXT WEEK. POTENT NORTHERN STREAM SHORTWAVE
MOVING ACROSS THE NORTHERN ROCKIES WILL PROPEL A ARCTIC COLD FRONT
SOUTHEAST ACROSS THE CWA BY TUESDAY MORNING. PRIOR TO THE FROPA...
A SURFACE LOW OVER THE FOUR CORNERS TRACKS NORTHEAST TO EAST
THROUGH SOUTHERN COLORADO AND KANSAS. POST-FRONTAL UPSLOPE NORTHEAST
LOW LEVEL FLOW...Q-G LIFT FROM RIGHT REAR QUAD OF UPPER JET AND
OVERRUNNING MOISTURE ACROSS A SHALLOW COLD AIR MASS WILL SET THE
STAGE FOR WIDESPREAD ACCUMULATING SNOW TUESDAY. GUSTY NORTH-NORTHEAST
WINDS WILL CREATE AREAS OF BLOWING/DRIFTING SNOW. IT`S EARLY TO
FORECAST SNOW AMOUNTS...BUT THIS SYSTEM WILL BE PROGRESSIVE WITH
SNOW TAPERING OFF FROM NORTHWEST TO SOUTHEAST TUESDAY NIGHT AS
COLD HIGH PRESSURE BUILDS ACROSS THE REGION. TEMPERATURES WILL BE
MILDER AHEAD OF THE FRONT MONDAY BUT AT LEAST 1O DEGREES BELOW
NORMAL. MUCH COLDER TEMPERATURES RETURN TUESDAY AND LAST THROUGH
MIDWEEK WITH HIGHS IN THE TEENS AND LOWS FROM 10 BELOW TO 10 ABOVE
ZERO. IN THE WAKE OF THE MIDWEEK SYSTEM...FLOW ALOFT BACKS FROM
NORTH- NORTHWEST TO MORE ZONAL THURSDAY. WESTERLY 700MB WINDS
PICK UP TO 40 KT THURSDAY RESULTING IN GUSTY DOWNSLOPE WINDS LEE
OF THE FRONT RANGE PUSHING THE MERCURY INTO THE 30S.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1106 AM MST FRI FEB 27 2015

A CHALLENGING AVIATION PERIOD SHAPING UP WITH ONGOING IFR
CIGS/VSBYS AT KCYS AND KSNY LIKELY IMPROVING BACK TO MVFR BY
19-21Z. OTHERWISE SHOULD SEE GENERALLY VFR CONDITIONS ELSEWHERE.
THE ONE TRICKY SPOT WILL BE AT KBFF WHERE CIGS WILL LIKELY BOUNCE
MVFR/VFR THRU THE AFTERNOON. WILL SEE MVFR CIGS RETURN TO
KCYS AND WRN NEBRASKA TERMINALS 00-03Z AS SOUTH/SOUTHEAST WINDS
PERSIST. WINDS WILL TURN TO WESTERLY AT KCYS BY AROUND 08Z WHICH
SHOULD ERODE LOWER CLOUDS BACK TO A VFR BKN060 LAYER. COLD FRONT
WILL BEGIN TO PUSH FROM NORTH TO SOUTH 15-18Z SATURDAY...WHICH
WILL LEAD TO ONCE AGAIN DETERIORATING CONDITIONS AND -SN CHANCES
RETURNING JUST BEYOND THE PERIOD SATURDAY AFTERNOON AND EVENING.

&&

.FIRE WEATHER...
ISSUED AT 245 AM MST FRI FEB 27 2015

NO FIRE WEATHER CONCERNS OVER THE NEXT WEEK. TEMPERATURES WILL
CONTINUE TO REMAIN BELOW NORMAL. WIDESPREAD LIGHT SNOW COULD FALL
SATURDAY AFTERNOON THROUGH THE NIGHT...ESPECIALLY FOR AREAS ALONG
THE COLORADO BORDER.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

SHORT TERM...FINCH
LONG TERM...JAMSKI
AVIATION...CAH
FIRE WEATHER...FINCH




000
FXUS65 KCYS 271806
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1106 AM MST FRI FEB 27 2015

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 330 AM MST FRI FEB 27 2015

RADAR IMAGERY SHOWS LIGHT SNOW HAS REALLY LET UP ACROSS LARAMIE
COUNTY WITH ONLY VERY LIGHT SNOW OR FLURRIES. CANCELLED THE WINTER
WEATHER ADVISORY A BIT EARLY WITH MINIMAL ADDITIONAL ACCUMULATION
EXPECTED. COLD WIND CHILLS HAVE BEEN OCCURRING OVER THE SOUTHERN
LARAMIE RANGE WITH VALUES IN THE -20 TO -25 RANGE. WITH NOT MUCH
CHANGE IN THE TEMPS OR WINDS THROUGH SUNRISE...SEE NO REASON THAT
WIND CHILLS WILL REACH WARNING CRITERIA(-30)...HOWEVER WILL CONTINUE
TO MONITOR. SOUTHERLY WINDS WILL PERSIST THROUGH THE AFTN ACROSS
THE PLAINS WITH LOW LEVEL UPSLOPE ALONG THE CHEYENNE RIDGE. ALL
MODELS SHOW LOW CLOUDS BEING QUITE PERSISTENT ALONG THE CHEYENNE
RIDGE AND INTO THE SOUTHERN PANHANDLE THROUGH THE EARLY AFTN WHICH
WILL KEEP TEMPS FROM WARMING TOO MUCH COMPARED TO YESTERDAY. OTHER
AREAS WHERE CLEARING OCCURS WILL WARM 5-10 DEGREES...BUT THAT
STILL PUTS US AROUND 20 DEGREES BELOW NORMAL FOR LATE FEB. PRETTY
QUIET WEATHER FROM THIS EVENING THROUGH MIDDAY SATURDAY. WINDS
WILL BE WEAK AND RADIATIONAL COOLING WILL BE BETTER TONIGHT WITH
LESS LOW CLOUDS PRESENT...SO LOWS WILL ONCE AGAIN FALL INTO THE
SINGLE DIGITS.

ANOTHER LIGHT SNOW EVENT APPEARS POSSIBLE FROM MAINLY SAT AFTN
THROUGH SAT NIGHT. THE 00Z EURO HOWEVER CONTINUES TO BE THE OUTLIER
IN SHOWING ALMOST ALL THE QPF TO THE SOUTH OF THE COLORADO BORDER.
THE NAM HAS COME MORE IN LINE WITH THE CONSISTENTLY WETTER GFS...
SHOWING WIDESPREAD 0.1-0.2 INCHES OVER MUCH OF THE CWA. WITH LOW
LEVEL UPSLOPE AND ISENTROPIC LIFT BEING THE PRIMARY FORCING
MECHANISMS... STILL BELIEVE THAT MOST LOCATIONS WILL ONLY PICK UP
A FEW INCHES AND BEING LARGELY SUB-ADVISORY. WITH WINDS LARGELY
REMAINING BELOW 15 KTS...AREAS OF BLOWING SNOW WILL NOT BE A
CONCERN. PRECIP COMES TO AN END BY LATE SUN MORNING WITH ANOTHER
CHILLY DAY IN STORE.

.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 AM MST FRI FEB 27 2015

00Z MEDIUM RANGE MODELS ARE IN GOOD AGREEMENT PORTRAYING A SPLIT
FLOW ALOFT WITH A MORE PROGRESSIVE NORTHERN STREAM AND SLOWER
SOUTHERN STREAM. WEST-SOUTHWEST FLOW ALOFT AHEAD OF CA/NV TROUGH
WILL ADVECT ABUNDANT PACIFIC MOISTURE ACROSS THE FOUR CORNERS AND
CENTRAL ROCKIES EARLY NEXT WEEK. POTENT NORTHERN STREAM SHORTWAVE
MOVING ACROSS THE NORTHERN ROCKIES WILL PROPEL A ARCTIC COLD FRONT
SOUTHEAST ACROSS THE CWA BY TUESDAY MORNING. PRIOR TO THE FROPA...
A SURFACE LOW OVER THE FOUR CORNERS TRACKS NORTHEAST TO EAST
THROUGH SOUTHERN COLORADO AND KANSAS. POST-FRONTAL UPSLOPE NORTHEAST
LOW LEVEL FLOW...Q-G LIFT FROM RIGHT REAR QUAD OF UPPER JET AND
OVERRUNNING MOISTURE ACROSS A SHALLOW COLD AIR MASS WILL SET THE
STAGE FOR WIDESPREAD ACCUMULATING SNOW TUESDAY. GUSTY NORTH-NORTHEAST
WINDS WILL CREATE AREAS OF BLOWING/DRIFTING SNOW. IT`S EARLY TO
FORECAST SNOW AMOUNTS...BUT THIS SYSTEM WILL BE PROGRESSIVE WITH
SNOW TAPERING OFF FROM NORTHWEST TO SOUTHEAST TUESDAY NIGHT AS
COLD HIGH PRESSURE BUILDS ACROSS THE REGION. TEMPERATURES WILL BE
MILDER AHEAD OF THE FRONT MONDAY BUT AT LEAST 1O DEGREES BELOW
NORMAL. MUCH COLDER TEMPERATURES RETURN TUESDAY AND LAST THROUGH
MIDWEEK WITH HIGHS IN THE TEENS AND LOWS FROM 10 BELOW TO 10 ABOVE
ZERO. IN THE WAKE OF THE MIDWEEK SYSTEM...FLOW ALOFT BACKS FROM
NORTH- NORTHWEST TO MORE ZONAL THURSDAY. WESTERLY 700MB WINDS
PICK UP TO 40 KT THURSDAY RESULTING IN GUSTY DOWNSLOPE WINDS LEE
OF THE FRONT RANGE PUSHING THE MERCURY INTO THE 30S.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1106 AM MST FRI FEB 27 2015

A CHALLENGING AVIATION PERIOD SHAPING UP WITH ONGOING IFR
CIGS/VSBYS AT KCYS AND KSNY LIKELY IMPROVING BACK TO MVFR BY
19-21Z. OTHERWISE SHOULD SEE GENERALLY VFR CONDITIONS ELSEWHERE.
THE ONE TRICKY SPOT WILL BE AT KBFF WHERE CIGS WILL LIKELY BOUNCE
MVFR/VFR THRU THE AFTERNOON. WILL SEE MVFR CIGS RETURN TO
KCYS AND WRN NEBRASKA TERMINALS 00-03Z AS SOUTH/SOUTHEAST WINDS
PERSIST. WINDS WILL TURN TO WESTERLY AT KCYS BY AROUND 08Z WHICH
SHOULD ERODE LOWER CLOUDS BACK TO A VFR BKN060 LAYER. COLD FRONT
WILL BEGIN TO PUSH FROM NORTH TO SOUTH 15-18Z SATURDAY...WHICH
WILL LEAD TO ONCE AGAIN DETERIORATING CONDITIONS AND -SN CHANCES
RETURNING JUST BEYOND THE PERIOD SATURDAY AFTERNOON AND EVENING.

&&

.FIRE WEATHER...
ISSUED AT 245 AM MST FRI FEB 27 2015

NO FIRE WEATHER CONCERNS OVER THE NEXT WEEK. TEMPERATURES WILL
CONTINUE TO REMAIN BELOW NORMAL. WIDESPREAD LIGHT SNOW COULD FALL
SATURDAY AFTERNOON THROUGH THE NIGHT...ESPECIALLY FOR AREAS ALONG
THE COLORADO BORDER.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

SHORT TERM...FINCH
LONG TERM...JAMSKI
AVIATION...CAH
FIRE WEATHER...FINCH



000
FXUS65 KCYS 271806
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1106 AM MST FRI FEB 27 2015

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 330 AM MST FRI FEB 27 2015

RADAR IMAGERY SHOWS LIGHT SNOW HAS REALLY LET UP ACROSS LARAMIE
COUNTY WITH ONLY VERY LIGHT SNOW OR FLURRIES. CANCELLED THE WINTER
WEATHER ADVISORY A BIT EARLY WITH MINIMAL ADDITIONAL ACCUMULATION
EXPECTED. COLD WIND CHILLS HAVE BEEN OCCURRING OVER THE SOUTHERN
LARAMIE RANGE WITH VALUES IN THE -20 TO -25 RANGE. WITH NOT MUCH
CHANGE IN THE TEMPS OR WINDS THROUGH SUNRISE...SEE NO REASON THAT
WIND CHILLS WILL REACH WARNING CRITERIA(-30)...HOWEVER WILL CONTINUE
TO MONITOR. SOUTHERLY WINDS WILL PERSIST THROUGH THE AFTN ACROSS
THE PLAINS WITH LOW LEVEL UPSLOPE ALONG THE CHEYENNE RIDGE. ALL
MODELS SHOW LOW CLOUDS BEING QUITE PERSISTENT ALONG THE CHEYENNE
RIDGE AND INTO THE SOUTHERN PANHANDLE THROUGH THE EARLY AFTN WHICH
WILL KEEP TEMPS FROM WARMING TOO MUCH COMPARED TO YESTERDAY. OTHER
AREAS WHERE CLEARING OCCURS WILL WARM 5-10 DEGREES...BUT THAT
STILL PUTS US AROUND 20 DEGREES BELOW NORMAL FOR LATE FEB. PRETTY
QUIET WEATHER FROM THIS EVENING THROUGH MIDDAY SATURDAY. WINDS
WILL BE WEAK AND RADIATIONAL COOLING WILL BE BETTER TONIGHT WITH
LESS LOW CLOUDS PRESENT...SO LOWS WILL ONCE AGAIN FALL INTO THE
SINGLE DIGITS.

ANOTHER LIGHT SNOW EVENT APPEARS POSSIBLE FROM MAINLY SAT AFTN
THROUGH SAT NIGHT. THE 00Z EURO HOWEVER CONTINUES TO BE THE OUTLIER
IN SHOWING ALMOST ALL THE QPF TO THE SOUTH OF THE COLORADO BORDER.
THE NAM HAS COME MORE IN LINE WITH THE CONSISTENTLY WETTER GFS...
SHOWING WIDESPREAD 0.1-0.2 INCHES OVER MUCH OF THE CWA. WITH LOW
LEVEL UPSLOPE AND ISENTROPIC LIFT BEING THE PRIMARY FORCING
MECHANISMS... STILL BELIEVE THAT MOST LOCATIONS WILL ONLY PICK UP
A FEW INCHES AND BEING LARGELY SUB-ADVISORY. WITH WINDS LARGELY
REMAINING BELOW 15 KTS...AREAS OF BLOWING SNOW WILL NOT BE A
CONCERN. PRECIP COMES TO AN END BY LATE SUN MORNING WITH ANOTHER
CHILLY DAY IN STORE.

.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 AM MST FRI FEB 27 2015

00Z MEDIUM RANGE MODELS ARE IN GOOD AGREEMENT PORTRAYING A SPLIT
FLOW ALOFT WITH A MORE PROGRESSIVE NORTHERN STREAM AND SLOWER
SOUTHERN STREAM. WEST-SOUTHWEST FLOW ALOFT AHEAD OF CA/NV TROUGH
WILL ADVECT ABUNDANT PACIFIC MOISTURE ACROSS THE FOUR CORNERS AND
CENTRAL ROCKIES EARLY NEXT WEEK. POTENT NORTHERN STREAM SHORTWAVE
MOVING ACROSS THE NORTHERN ROCKIES WILL PROPEL A ARCTIC COLD FRONT
SOUTHEAST ACROSS THE CWA BY TUESDAY MORNING. PRIOR TO THE FROPA...
A SURFACE LOW OVER THE FOUR CORNERS TRACKS NORTHEAST TO EAST
THROUGH SOUTHERN COLORADO AND KANSAS. POST-FRONTAL UPSLOPE NORTHEAST
LOW LEVEL FLOW...Q-G LIFT FROM RIGHT REAR QUAD OF UPPER JET AND
OVERRUNNING MOISTURE ACROSS A SHALLOW COLD AIR MASS WILL SET THE
STAGE FOR WIDESPREAD ACCUMULATING SNOW TUESDAY. GUSTY NORTH-NORTHEAST
WINDS WILL CREATE AREAS OF BLOWING/DRIFTING SNOW. IT`S EARLY TO
FORECAST SNOW AMOUNTS...BUT THIS SYSTEM WILL BE PROGRESSIVE WITH
SNOW TAPERING OFF FROM NORTHWEST TO SOUTHEAST TUESDAY NIGHT AS
COLD HIGH PRESSURE BUILDS ACROSS THE REGION. TEMPERATURES WILL BE
MILDER AHEAD OF THE FRONT MONDAY BUT AT LEAST 1O DEGREES BELOW
NORMAL. MUCH COLDER TEMPERATURES RETURN TUESDAY AND LAST THROUGH
MIDWEEK WITH HIGHS IN THE TEENS AND LOWS FROM 10 BELOW TO 10 ABOVE
ZERO. IN THE WAKE OF THE MIDWEEK SYSTEM...FLOW ALOFT BACKS FROM
NORTH- NORTHWEST TO MORE ZONAL THURSDAY. WESTERLY 700MB WINDS
PICK UP TO 40 KT THURSDAY RESULTING IN GUSTY DOWNSLOPE WINDS LEE
OF THE FRONT RANGE PUSHING THE MERCURY INTO THE 30S.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1106 AM MST FRI FEB 27 2015

A CHALLENGING AVIATION PERIOD SHAPING UP WITH ONGOING IFR
CIGS/VSBYS AT KCYS AND KSNY LIKELY IMPROVING BACK TO MVFR BY
19-21Z. OTHERWISE SHOULD SEE GENERALLY VFR CONDITIONS ELSEWHERE.
THE ONE TRICKY SPOT WILL BE AT KBFF WHERE CIGS WILL LIKELY BOUNCE
MVFR/VFR THRU THE AFTERNOON. WILL SEE MVFR CIGS RETURN TO
KCYS AND WRN NEBRASKA TERMINALS 00-03Z AS SOUTH/SOUTHEAST WINDS
PERSIST. WINDS WILL TURN TO WESTERLY AT KCYS BY AROUND 08Z WHICH
SHOULD ERODE LOWER CLOUDS BACK TO A VFR BKN060 LAYER. COLD FRONT
WILL BEGIN TO PUSH FROM NORTH TO SOUTH 15-18Z SATURDAY...WHICH
WILL LEAD TO ONCE AGAIN DETERIORATING CONDITIONS AND -SN CHANCES
RETURNING JUST BEYOND THE PERIOD SATURDAY AFTERNOON AND EVENING.

&&

.FIRE WEATHER...
ISSUED AT 245 AM MST FRI FEB 27 2015

NO FIRE WEATHER CONCERNS OVER THE NEXT WEEK. TEMPERATURES WILL
CONTINUE TO REMAIN BELOW NORMAL. WIDESPREAD LIGHT SNOW COULD FALL
SATURDAY AFTERNOON THROUGH THE NIGHT...ESPECIALLY FOR AREAS ALONG
THE COLORADO BORDER.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

SHORT TERM...FINCH
LONG TERM...JAMSKI
AVIATION...CAH
FIRE WEATHER...FINCH




000
FXUS65 KRIW 271741
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1041 AM MST FRI FEB 27 2015

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT

A PUSH OF MOISTURE MOVING IN THE NORTHWEST FLOW WILL KEEP SOME LIGHT
SHOWER ACTIVITY ACROSS NORTHWESTERN WYOMING TODAY. THE VERY WEAK
DISTURBANCE USHERING THIS MOISTURE PUSH WILL CONTINUE TO MOVE EAST
THROUGH THE FORECAST AREA OVERNIGHT. THE MOISTURE IS EXPECTED TO
INCREASE AND SPREAD ACROSS THE NORTHERN THIRD OF THE FORECAST AREA
BY SATURDAY MORNING. TEMPERATURES WILL BE ABLE TO WARM
SLIGHTLY...THOUGH WILL STILL REMAIN COOL.

AN AREA OF LOW PRESSURE OVER THE PACIFIC NORTHWEST WILL DIVE SOUTH
ON SATURDAY...ARRIVING OVER CALIFORNIA SATURDAY. AS THIS SYSTEM
MOVES SOUTH IT WILL BRING COOLING TEMPERATURES...AND SEND ADDITIONAL
PULSES OF MOISTURE OVER THE FORECAST AREA. THE BEST OF THESE PULSES
IS NOT EXPECTED TO ARRIVE UNTIL LATE SATURDAY AFTERNOON...AND WILL
PRIMARILY IMPACT SOUTHWESTERN WYOMING. THIS SYSTEM WILL CONTINUE TO
MOVE SOUTH THROUGH SUNDAY WITH PRECIPITATION LINGERING OVER SOUTHERN
WYOMING THROUGH SUNDAY AFTERNOON. A BRIEF PERIOD OF DRY CONDITIONS
POSSIBLE SUNDAY NIGHT...THOUGH MODELS DO INDICATE THE POTENTIAL FOR
ADDITIONAL MOISTURE ACROSS SOUTHERN WYOMING DURING THE LATE EVENING
HOURS OF SUNDAY.

.LONG TERM...MONDAY THROUGH FRIDAY

MAIN CHANGE FOR TONIGHT ARE THE MODELS NOT SHOWING AS MUCH ENERGY
DIGGING INTO THE GREAT BASIN/INTER-MOUNTAIN WEST MONDAY NIGHT AND
TUESDAY AS LAST NIGHT. MORE SHEARING OR JUST OVERALL LESS ENERGY.
THE SYSTEM THE MODELS TRACK FROM KAMCHATKA YESTERDAY IS STILL THE
SAME BUT THE END SOLUTION IS JUST DIFFERENT. STILL LOOKS LIKE SNOW
SPREADING S AND SE ACROSS THE AREA MONDAY NIGHT INTO EARLY TUESDAY
AND TURNING SHARPLY COLDER. SOME FAIRLY DECENT QG FORCING MAY
COMBINE WITH SOME INITIAL RRQ JET DYNAMICS MONDAY NIGHT AND THEN
LEFT EXIT REGION ON TUE WITH THE NEXT JET APPROACHING. WITH LESS
ENERGY TO THE WEST...MOVEMENT IS FASTER AND NOW WE MAY ACTUALLY
CLEAR BY WEDNESDAY MORNING LEADING TO SOME BITTER COLD LOWS. A
COLD COUPLE DAYS THOUGH FOR TUE AND WED. ON THE PLUS SIDE...THE
RIDGE FLATTENS MORE QUICKLY WITH A RATHER FAST MODERATION THURSDAY
INTO FRIDAY ON THE GFS. BACK TRACKING A LITTLE...THE WEEKEND
SYSTEM ENERGY LINGERS JUST TO THE SOUTH TO START THIS PERIOD
MONDAY WITH CONTINUED POTENTIAL FOR CLOUDS AND MAYBE EVEN SOME
VERY LIGHT PCPN IN OUR FAR SRN ZONES. OTHERWISE... DETERIORATING
CONDS BEGINNING LATER MONDAY ONWARD WITH OUR AFOREMENTIONED MONDAY
NIGHT/TUE SYSTEM FAST APPROACHING. RIGHT AT THE END OF THE MEDIUM
RANGE PERIOD...THE MODELS DIVERGE AS TO THE HANDLING OF A PIECE OF
ENERGY CURRENTLY COMING OFF THE ASIA COAST. THE GFS BRINGS IT
FURTHER OVER THE RIDGE AND INTO THE NRN PLAINS WHILE THE EURO
BRINGS THIS SHORTWAVE AT A LITTLE LOWER LATITUDE ALLOWING IT TO
DIG SE INTO OUR AREA NEXT FRIDAY NIGHT. KEEPING IT DRY FOR NOW.
THE GFS WOULD HAVE A MUCH NICER DAY ON FRIDAY WHILE THE ECMWF IS
ALREADY DIGGING THE LOW TOWARDS US WITH FALLING TEMPS BEHIND A
COLD FRONT.

&&

.AVIATION.../18Z ISSUANCE/

FREQUENT MOUNTAIN OBSCURATIONS ALONG AND WEST OF THE CONTINENTAL
DIVIDE THROUGH THE FORECAST PERIOD. ALSO...FOOTHILL OBSCURATIONS IN
THE VICINITY OF KLND AND KRIW WILL DISSIPATE EARLY THIS AFTERNOON.
EXPECT MORE WIDESPREAD OBSCURATIONS DEVELOPING FROM NORTH TO SOUTH
AFTER 03Z/SAT THROUGH 09Z/SAT.

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

IFR/MVFR CONDITIONS WITH LOW STRATUS DECK AT KRIW AND KLND THIS
MORNING. EDGES HAVE BEEN SLOW TO ERODE. HAVE BACKED OFF THE
DISSIPATION OF THE STRATUS UNTIL 19Z-20Z. MORE SUNSHINE HAS BEEN
STARTING TO SHOW THROUGH SINCE 17Z. OTHER TERMINALS WILL BE VFR
THROUGH THIS AFTERNOON. ANOTHER SURGE OF COLD AIR WILL BRING A
RETURN OF LOW CLOUDS AND MVFR OR LOW VFR CEILINGS OVER NORTHERN
WYOMING BETWEEN 00Z-06Z/SAT. THIS AREA OF CLOUDS AND LIGHT SNOW WILL
PUSH SOUTH THROUGH THE NIGHT. KWRL IS THE LEAST LIKELY OF THE
TERMINALS TO SEE AN EXTENDED PERIOD OF LIGHT SNOW. BEST CHANCE FOR
MVFR VISIBILITIES THROUGH 18Z/SAT WILL BE FROM KLND-KCPR WHERE WEAK
UPSLOPE WOULD BE FAVORABLE AFTER THE COLD FRONT PUSHES SOUTH.

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

AREAS OF LOW CLOUDS AND LIGHT SNOW ACROSS PORTIONS OF THE FAR WEST
MOUNTAINS AND VALLEYS THIS MORNING. IFR/MVFR CONDITIONS AT KJAC ARE
LIKELY TO HANG ON THROUGH ABOUT 00Z/SAT. EXPECT THAT WHILE
VISIBILITIES WILL IMPROVE CEILINGS WILL BE MVFR OR LOW VFR THROUGH
THE FORECAST PERIOD. MVFR STRATUS DECK WILL LIFT AT KBPI EARLY THIS
AFTERNOON. EXPECT CONDITIONS THERE AND AT KPNA TO REMAIN VFR THROUGH
THE FORECAST PERIOD. SOME PESKY STRATUS AROUND KRKS BUT BELIEVE THE
SUN WILL WIN OUT AND LEAVE VFR THROUGH TODAY. COLD FRONTAL SURGE
WILL BRING GUSTY EAST-NORTHEAST WIND TO KRKS BEGINNING BETWEEN
09Z/SAT AND 12Z/SAT. WHILE CONDITIONS WILL BE VFR THROUGH
18Z/SAT...POSSIBLE RETURN TO MVFR CONDITIONS WITH SNOW/WIND
COMBINATION BY 00Z/SUN OR SHORTLY THEREAFTER. WILL BE ADDRESSING
THIS MORE WITH THE 00Z TAF SET THIS AFTERNOON.

&&

.FIRE WEATHER...

A SOMEWHAT BUSY FORECAST PERIOD ACROSS THE AREA. SHOWER ACTIVITY
WILL REMAIN POSSIBLE OVER THE NORTHERN THIRD OF THE AREA AS A
DISTURBANCES MOVES ACROSS THE AREA IN THE CONTINUED NORTHWEST FLOW.
AFTER A VERY SLIGHT WARMING TODAY...TEMPERATURES WILL AGAIN COOL
SATURDAY AS AN AREA OF LOW PRESSURE MOVES SOUTH ALONG THE PACIFIC
COASTLINE. AS THIS SYSTEM PROGRESSES...IT WILL SPREAD ADDITIONAL
SHOWERS ACROSS SOUTHWESTERN WYOMING...WITH SOUTHERN WYOMING
EXPERIENCING THE BRUNT OF THE SHOWER ACTIVITY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...PS
AVIATION...CNJ
FIRE WEATHER...BRANHAM






000
FXUS65 KRIW 271741
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1041 AM MST FRI FEB 27 2015

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT

A PUSH OF MOISTURE MOVING IN THE NORTHWEST FLOW WILL KEEP SOME LIGHT
SHOWER ACTIVITY ACROSS NORTHWESTERN WYOMING TODAY. THE VERY WEAK
DISTURBANCE USHERING THIS MOISTURE PUSH WILL CONTINUE TO MOVE EAST
THROUGH THE FORECAST AREA OVERNIGHT. THE MOISTURE IS EXPECTED TO
INCREASE AND SPREAD ACROSS THE NORTHERN THIRD OF THE FORECAST AREA
BY SATURDAY MORNING. TEMPERATURES WILL BE ABLE TO WARM
SLIGHTLY...THOUGH WILL STILL REMAIN COOL.

AN AREA OF LOW PRESSURE OVER THE PACIFIC NORTHWEST WILL DIVE SOUTH
ON SATURDAY...ARRIVING OVER CALIFORNIA SATURDAY. AS THIS SYSTEM
MOVES SOUTH IT WILL BRING COOLING TEMPERATURES...AND SEND ADDITIONAL
PULSES OF MOISTURE OVER THE FORECAST AREA. THE BEST OF THESE PULSES
IS NOT EXPECTED TO ARRIVE UNTIL LATE SATURDAY AFTERNOON...AND WILL
PRIMARILY IMPACT SOUTHWESTERN WYOMING. THIS SYSTEM WILL CONTINUE TO
MOVE SOUTH THROUGH SUNDAY WITH PRECIPITATION LINGERING OVER SOUTHERN
WYOMING THROUGH SUNDAY AFTERNOON. A BRIEF PERIOD OF DRY CONDITIONS
POSSIBLE SUNDAY NIGHT...THOUGH MODELS DO INDICATE THE POTENTIAL FOR
ADDITIONAL MOISTURE ACROSS SOUTHERN WYOMING DURING THE LATE EVENING
HOURS OF SUNDAY.

.LONG TERM...MONDAY THROUGH FRIDAY

MAIN CHANGE FOR TONIGHT ARE THE MODELS NOT SHOWING AS MUCH ENERGY
DIGGING INTO THE GREAT BASIN/INTER-MOUNTAIN WEST MONDAY NIGHT AND
TUESDAY AS LAST NIGHT. MORE SHEARING OR JUST OVERALL LESS ENERGY.
THE SYSTEM THE MODELS TRACK FROM KAMCHATKA YESTERDAY IS STILL THE
SAME BUT THE END SOLUTION IS JUST DIFFERENT. STILL LOOKS LIKE SNOW
SPREADING S AND SE ACROSS THE AREA MONDAY NIGHT INTO EARLY TUESDAY
AND TURNING SHARPLY COLDER. SOME FAIRLY DECENT QG FORCING MAY
COMBINE WITH SOME INITIAL RRQ JET DYNAMICS MONDAY NIGHT AND THEN
LEFT EXIT REGION ON TUE WITH THE NEXT JET APPROACHING. WITH LESS
ENERGY TO THE WEST...MOVEMENT IS FASTER AND NOW WE MAY ACTUALLY
CLEAR BY WEDNESDAY MORNING LEADING TO SOME BITTER COLD LOWS. A
COLD COUPLE DAYS THOUGH FOR TUE AND WED. ON THE PLUS SIDE...THE
RIDGE FLATTENS MORE QUICKLY WITH A RATHER FAST MODERATION THURSDAY
INTO FRIDAY ON THE GFS. BACK TRACKING A LITTLE...THE WEEKEND
SYSTEM ENERGY LINGERS JUST TO THE SOUTH TO START THIS PERIOD
MONDAY WITH CONTINUED POTENTIAL FOR CLOUDS AND MAYBE EVEN SOME
VERY LIGHT PCPN IN OUR FAR SRN ZONES. OTHERWISE... DETERIORATING
CONDS BEGINNING LATER MONDAY ONWARD WITH OUR AFOREMENTIONED MONDAY
NIGHT/TUE SYSTEM FAST APPROACHING. RIGHT AT THE END OF THE MEDIUM
RANGE PERIOD...THE MODELS DIVERGE AS TO THE HANDLING OF A PIECE OF
ENERGY CURRENTLY COMING OFF THE ASIA COAST. THE GFS BRINGS IT
FURTHER OVER THE RIDGE AND INTO THE NRN PLAINS WHILE THE EURO
BRINGS THIS SHORTWAVE AT A LITTLE LOWER LATITUDE ALLOWING IT TO
DIG SE INTO OUR AREA NEXT FRIDAY NIGHT. KEEPING IT DRY FOR NOW.
THE GFS WOULD HAVE A MUCH NICER DAY ON FRIDAY WHILE THE ECMWF IS
ALREADY DIGGING THE LOW TOWARDS US WITH FALLING TEMPS BEHIND A
COLD FRONT.

&&

.AVIATION.../18Z ISSUANCE/

FREQUENT MOUNTAIN OBSCURATIONS ALONG AND WEST OF THE CONTINENTAL
DIVIDE THROUGH THE FORECAST PERIOD. ALSO...FOOTHILL OBSCURATIONS IN
THE VICINITY OF KLND AND KRIW WILL DISSIPATE EARLY THIS AFTERNOON.
EXPECT MORE WIDESPREAD OBSCURATIONS DEVELOPING FROM NORTH TO SOUTH
AFTER 03Z/SAT THROUGH 09Z/SAT.

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

IFR/MVFR CONDITIONS WITH LOW STRATUS DECK AT KRIW AND KLND THIS
MORNING. EDGES HAVE BEEN SLOW TO ERODE. HAVE BACKED OFF THE
DISSIPATION OF THE STRATUS UNTIL 19Z-20Z. MORE SUNSHINE HAS BEEN
STARTING TO SHOW THROUGH SINCE 17Z. OTHER TERMINALS WILL BE VFR
THROUGH THIS AFTERNOON. ANOTHER SURGE OF COLD AIR WILL BRING A
RETURN OF LOW CLOUDS AND MVFR OR LOW VFR CEILINGS OVER NORTHERN
WYOMING BETWEEN 00Z-06Z/SAT. THIS AREA OF CLOUDS AND LIGHT SNOW WILL
PUSH SOUTH THROUGH THE NIGHT. KWRL IS THE LEAST LIKELY OF THE
TERMINALS TO SEE AN EXTENDED PERIOD OF LIGHT SNOW. BEST CHANCE FOR
MVFR VISIBILITIES THROUGH 18Z/SAT WILL BE FROM KLND-KCPR WHERE WEAK
UPSLOPE WOULD BE FAVORABLE AFTER THE COLD FRONT PUSHES SOUTH.

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

AREAS OF LOW CLOUDS AND LIGHT SNOW ACROSS PORTIONS OF THE FAR WEST
MOUNTAINS AND VALLEYS THIS MORNING. IFR/MVFR CONDITIONS AT KJAC ARE
LIKELY TO HANG ON THROUGH ABOUT 00Z/SAT. EXPECT THAT WHILE
VISIBILITIES WILL IMPROVE CEILINGS WILL BE MVFR OR LOW VFR THROUGH
THE FORECAST PERIOD. MVFR STRATUS DECK WILL LIFT AT KBPI EARLY THIS
AFTERNOON. EXPECT CONDITIONS THERE AND AT KPNA TO REMAIN VFR THROUGH
THE FORECAST PERIOD. SOME PESKY STRATUS AROUND KRKS BUT BELIEVE THE
SUN WILL WIN OUT AND LEAVE VFR THROUGH TODAY. COLD FRONTAL SURGE
WILL BRING GUSTY EAST-NORTHEAST WIND TO KRKS BEGINNING BETWEEN
09Z/SAT AND 12Z/SAT. WHILE CONDITIONS WILL BE VFR THROUGH
18Z/SAT...POSSIBLE RETURN TO MVFR CONDITIONS WITH SNOW/WIND
COMBINATION BY 00Z/SUN OR SHORTLY THEREAFTER. WILL BE ADDRESSING
THIS MORE WITH THE 00Z TAF SET THIS AFTERNOON.

&&

.FIRE WEATHER...

A SOMEWHAT BUSY FORECAST PERIOD ACROSS THE AREA. SHOWER ACTIVITY
WILL REMAIN POSSIBLE OVER THE NORTHERN THIRD OF THE AREA AS A
DISTURBANCES MOVES ACROSS THE AREA IN THE CONTINUED NORTHWEST FLOW.
AFTER A VERY SLIGHT WARMING TODAY...TEMPERATURES WILL AGAIN COOL
SATURDAY AS AN AREA OF LOW PRESSURE MOVES SOUTH ALONG THE PACIFIC
COASTLINE. AS THIS SYSTEM PROGRESSES...IT WILL SPREAD ADDITIONAL
SHOWERS ACROSS SOUTHWESTERN WYOMING...WITH SOUTHERN WYOMING
EXPERIENCING THE BRUNT OF THE SHOWER ACTIVITY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...PS
AVIATION...CNJ
FIRE WEATHER...BRANHAM





000
FXUS65 KRIW 271741
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1041 AM MST FRI FEB 27 2015

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT

A PUSH OF MOISTURE MOVING IN THE NORTHWEST FLOW WILL KEEP SOME LIGHT
SHOWER ACTIVITY ACROSS NORTHWESTERN WYOMING TODAY. THE VERY WEAK
DISTURBANCE USHERING THIS MOISTURE PUSH WILL CONTINUE TO MOVE EAST
THROUGH THE FORECAST AREA OVERNIGHT. THE MOISTURE IS EXPECTED TO
INCREASE AND SPREAD ACROSS THE NORTHERN THIRD OF THE FORECAST AREA
BY SATURDAY MORNING. TEMPERATURES WILL BE ABLE TO WARM
SLIGHTLY...THOUGH WILL STILL REMAIN COOL.

AN AREA OF LOW PRESSURE OVER THE PACIFIC NORTHWEST WILL DIVE SOUTH
ON SATURDAY...ARRIVING OVER CALIFORNIA SATURDAY. AS THIS SYSTEM
MOVES SOUTH IT WILL BRING COOLING TEMPERATURES...AND SEND ADDITIONAL
PULSES OF MOISTURE OVER THE FORECAST AREA. THE BEST OF THESE PULSES
IS NOT EXPECTED TO ARRIVE UNTIL LATE SATURDAY AFTERNOON...AND WILL
PRIMARILY IMPACT SOUTHWESTERN WYOMING. THIS SYSTEM WILL CONTINUE TO
MOVE SOUTH THROUGH SUNDAY WITH PRECIPITATION LINGERING OVER SOUTHERN
WYOMING THROUGH SUNDAY AFTERNOON. A BRIEF PERIOD OF DRY CONDITIONS
POSSIBLE SUNDAY NIGHT...THOUGH MODELS DO INDICATE THE POTENTIAL FOR
ADDITIONAL MOISTURE ACROSS SOUTHERN WYOMING DURING THE LATE EVENING
HOURS OF SUNDAY.

.LONG TERM...MONDAY THROUGH FRIDAY

MAIN CHANGE FOR TONIGHT ARE THE MODELS NOT SHOWING AS MUCH ENERGY
DIGGING INTO THE GREAT BASIN/INTER-MOUNTAIN WEST MONDAY NIGHT AND
TUESDAY AS LAST NIGHT. MORE SHEARING OR JUST OVERALL LESS ENERGY.
THE SYSTEM THE MODELS TRACK FROM KAMCHATKA YESTERDAY IS STILL THE
SAME BUT THE END SOLUTION IS JUST DIFFERENT. STILL LOOKS LIKE SNOW
SPREADING S AND SE ACROSS THE AREA MONDAY NIGHT INTO EARLY TUESDAY
AND TURNING SHARPLY COLDER. SOME FAIRLY DECENT QG FORCING MAY
COMBINE WITH SOME INITIAL RRQ JET DYNAMICS MONDAY NIGHT AND THEN
LEFT EXIT REGION ON TUE WITH THE NEXT JET APPROACHING. WITH LESS
ENERGY TO THE WEST...MOVEMENT IS FASTER AND NOW WE MAY ACTUALLY
CLEAR BY WEDNESDAY MORNING LEADING TO SOME BITTER COLD LOWS. A
COLD COUPLE DAYS THOUGH FOR TUE AND WED. ON THE PLUS SIDE...THE
RIDGE FLATTENS MORE QUICKLY WITH A RATHER FAST MODERATION THURSDAY
INTO FRIDAY ON THE GFS. BACK TRACKING A LITTLE...THE WEEKEND
SYSTEM ENERGY LINGERS JUST TO THE SOUTH TO START THIS PERIOD
MONDAY WITH CONTINUED POTENTIAL FOR CLOUDS AND MAYBE EVEN SOME
VERY LIGHT PCPN IN OUR FAR SRN ZONES. OTHERWISE... DETERIORATING
CONDS BEGINNING LATER MONDAY ONWARD WITH OUR AFOREMENTIONED MONDAY
NIGHT/TUE SYSTEM FAST APPROACHING. RIGHT AT THE END OF THE MEDIUM
RANGE PERIOD...THE MODELS DIVERGE AS TO THE HANDLING OF A PIECE OF
ENERGY CURRENTLY COMING OFF THE ASIA COAST. THE GFS BRINGS IT
FURTHER OVER THE RIDGE AND INTO THE NRN PLAINS WHILE THE EURO
BRINGS THIS SHORTWAVE AT A LITTLE LOWER LATITUDE ALLOWING IT TO
DIG SE INTO OUR AREA NEXT FRIDAY NIGHT. KEEPING IT DRY FOR NOW.
THE GFS WOULD HAVE A MUCH NICER DAY ON FRIDAY WHILE THE ECMWF IS
ALREADY DIGGING THE LOW TOWARDS US WITH FALLING TEMPS BEHIND A
COLD FRONT.

&&

.AVIATION.../18Z ISSUANCE/

FREQUENT MOUNTAIN OBSCURATIONS ALONG AND WEST OF THE CONTINENTAL
DIVIDE THROUGH THE FORECAST PERIOD. ALSO...FOOTHILL OBSCURATIONS IN
THE VICINITY OF KLND AND KRIW WILL DISSIPATE EARLY THIS AFTERNOON.
EXPECT MORE WIDESPREAD OBSCURATIONS DEVELOPING FROM NORTH TO SOUTH
AFTER 03Z/SAT THROUGH 09Z/SAT.

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

IFR/MVFR CONDITIONS WITH LOW STRATUS DECK AT KRIW AND KLND THIS
MORNING. EDGES HAVE BEEN SLOW TO ERODE. HAVE BACKED OFF THE
DISSIPATION OF THE STRATUS UNTIL 19Z-20Z. MORE SUNSHINE HAS BEEN
STARTING TO SHOW THROUGH SINCE 17Z. OTHER TERMINALS WILL BE VFR
THROUGH THIS AFTERNOON. ANOTHER SURGE OF COLD AIR WILL BRING A
RETURN OF LOW CLOUDS AND MVFR OR LOW VFR CEILINGS OVER NORTHERN
WYOMING BETWEEN 00Z-06Z/SAT. THIS AREA OF CLOUDS AND LIGHT SNOW WILL
PUSH SOUTH THROUGH THE NIGHT. KWRL IS THE LEAST LIKELY OF THE
TERMINALS TO SEE AN EXTENDED PERIOD OF LIGHT SNOW. BEST CHANCE FOR
MVFR VISIBILITIES THROUGH 18Z/SAT WILL BE FROM KLND-KCPR WHERE WEAK
UPSLOPE WOULD BE FAVORABLE AFTER THE COLD FRONT PUSHES SOUTH.

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

AREAS OF LOW CLOUDS AND LIGHT SNOW ACROSS PORTIONS OF THE FAR WEST
MOUNTAINS AND VALLEYS THIS MORNING. IFR/MVFR CONDITIONS AT KJAC ARE
LIKELY TO HANG ON THROUGH ABOUT 00Z/SAT. EXPECT THAT WHILE
VISIBILITIES WILL IMPROVE CEILINGS WILL BE MVFR OR LOW VFR THROUGH
THE FORECAST PERIOD. MVFR STRATUS DECK WILL LIFT AT KBPI EARLY THIS
AFTERNOON. EXPECT CONDITIONS THERE AND AT KPNA TO REMAIN VFR THROUGH
THE FORECAST PERIOD. SOME PESKY STRATUS AROUND KRKS BUT BELIEVE THE
SUN WILL WIN OUT AND LEAVE VFR THROUGH TODAY. COLD FRONTAL SURGE
WILL BRING GUSTY EAST-NORTHEAST WIND TO KRKS BEGINNING BETWEEN
09Z/SAT AND 12Z/SAT. WHILE CONDITIONS WILL BE VFR THROUGH
18Z/SAT...POSSIBLE RETURN TO MVFR CONDITIONS WITH SNOW/WIND
COMBINATION BY 00Z/SUN OR SHORTLY THEREAFTER. WILL BE ADDRESSING
THIS MORE WITH THE 00Z TAF SET THIS AFTERNOON.

&&

.FIRE WEATHER...

A SOMEWHAT BUSY FORECAST PERIOD ACROSS THE AREA. SHOWER ACTIVITY
WILL REMAIN POSSIBLE OVER THE NORTHERN THIRD OF THE AREA AS A
DISTURBANCES MOVES ACROSS THE AREA IN THE CONTINUED NORTHWEST FLOW.
AFTER A VERY SLIGHT WARMING TODAY...TEMPERATURES WILL AGAIN COOL
SATURDAY AS AN AREA OF LOW PRESSURE MOVES SOUTH ALONG THE PACIFIC
COASTLINE. AS THIS SYSTEM PROGRESSES...IT WILL SPREAD ADDITIONAL
SHOWERS ACROSS SOUTHWESTERN WYOMING...WITH SOUTHERN WYOMING
EXPERIENCING THE BRUNT OF THE SHOWER ACTIVITY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...PS
AVIATION...CNJ
FIRE WEATHER...BRANHAM





000
FXUS65 KRIW 271741
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1041 AM MST FRI FEB 27 2015

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT

A PUSH OF MOISTURE MOVING IN THE NORTHWEST FLOW WILL KEEP SOME LIGHT
SHOWER ACTIVITY ACROSS NORTHWESTERN WYOMING TODAY. THE VERY WEAK
DISTURBANCE USHERING THIS MOISTURE PUSH WILL CONTINUE TO MOVE EAST
THROUGH THE FORECAST AREA OVERNIGHT. THE MOISTURE IS EXPECTED TO
INCREASE AND SPREAD ACROSS THE NORTHERN THIRD OF THE FORECAST AREA
BY SATURDAY MORNING. TEMPERATURES WILL BE ABLE TO WARM
SLIGHTLY...THOUGH WILL STILL REMAIN COOL.

AN AREA OF LOW PRESSURE OVER THE PACIFIC NORTHWEST WILL DIVE SOUTH
ON SATURDAY...ARRIVING OVER CALIFORNIA SATURDAY. AS THIS SYSTEM
MOVES SOUTH IT WILL BRING COOLING TEMPERATURES...AND SEND ADDITIONAL
PULSES OF MOISTURE OVER THE FORECAST AREA. THE BEST OF THESE PULSES
IS NOT EXPECTED TO ARRIVE UNTIL LATE SATURDAY AFTERNOON...AND WILL
PRIMARILY IMPACT SOUTHWESTERN WYOMING. THIS SYSTEM WILL CONTINUE TO
MOVE SOUTH THROUGH SUNDAY WITH PRECIPITATION LINGERING OVER SOUTHERN
WYOMING THROUGH SUNDAY AFTERNOON. A BRIEF PERIOD OF DRY CONDITIONS
POSSIBLE SUNDAY NIGHT...THOUGH MODELS DO INDICATE THE POTENTIAL FOR
ADDITIONAL MOISTURE ACROSS SOUTHERN WYOMING DURING THE LATE EVENING
HOURS OF SUNDAY.

.LONG TERM...MONDAY THROUGH FRIDAY

MAIN CHANGE FOR TONIGHT ARE THE MODELS NOT SHOWING AS MUCH ENERGY
DIGGING INTO THE GREAT BASIN/INTER-MOUNTAIN WEST MONDAY NIGHT AND
TUESDAY AS LAST NIGHT. MORE SHEARING OR JUST OVERALL LESS ENERGY.
THE SYSTEM THE MODELS TRACK FROM KAMCHATKA YESTERDAY IS STILL THE
SAME BUT THE END SOLUTION IS JUST DIFFERENT. STILL LOOKS LIKE SNOW
SPREADING S AND SE ACROSS THE AREA MONDAY NIGHT INTO EARLY TUESDAY
AND TURNING SHARPLY COLDER. SOME FAIRLY DECENT QG FORCING MAY
COMBINE WITH SOME INITIAL RRQ JET DYNAMICS MONDAY NIGHT AND THEN
LEFT EXIT REGION ON TUE WITH THE NEXT JET APPROACHING. WITH LESS
ENERGY TO THE WEST...MOVEMENT IS FASTER AND NOW WE MAY ACTUALLY
CLEAR BY WEDNESDAY MORNING LEADING TO SOME BITTER COLD LOWS. A
COLD COUPLE DAYS THOUGH FOR TUE AND WED. ON THE PLUS SIDE...THE
RIDGE FLATTENS MORE QUICKLY WITH A RATHER FAST MODERATION THURSDAY
INTO FRIDAY ON THE GFS. BACK TRACKING A LITTLE...THE WEEKEND
SYSTEM ENERGY LINGERS JUST TO THE SOUTH TO START THIS PERIOD
MONDAY WITH CONTINUED POTENTIAL FOR CLOUDS AND MAYBE EVEN SOME
VERY LIGHT PCPN IN OUR FAR SRN ZONES. OTHERWISE... DETERIORATING
CONDS BEGINNING LATER MONDAY ONWARD WITH OUR AFOREMENTIONED MONDAY
NIGHT/TUE SYSTEM FAST APPROACHING. RIGHT AT THE END OF THE MEDIUM
RANGE PERIOD...THE MODELS DIVERGE AS TO THE HANDLING OF A PIECE OF
ENERGY CURRENTLY COMING OFF THE ASIA COAST. THE GFS BRINGS IT
FURTHER OVER THE RIDGE AND INTO THE NRN PLAINS WHILE THE EURO
BRINGS THIS SHORTWAVE AT A LITTLE LOWER LATITUDE ALLOWING IT TO
DIG SE INTO OUR AREA NEXT FRIDAY NIGHT. KEEPING IT DRY FOR NOW.
THE GFS WOULD HAVE A MUCH NICER DAY ON FRIDAY WHILE THE ECMWF IS
ALREADY DIGGING THE LOW TOWARDS US WITH FALLING TEMPS BEHIND A
COLD FRONT.

&&

.AVIATION.../18Z ISSUANCE/

FREQUENT MOUNTAIN OBSCURATIONS ALONG AND WEST OF THE CONTINENTAL
DIVIDE THROUGH THE FORECAST PERIOD. ALSO...FOOTHILL OBSCURATIONS IN
THE VICINITY OF KLND AND KRIW WILL DISSIPATE EARLY THIS AFTERNOON.
EXPECT MORE WIDESPREAD OBSCURATIONS DEVELOPING FROM NORTH TO SOUTH
AFTER 03Z/SAT THROUGH 09Z/SAT.

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

IFR/MVFR CONDITIONS WITH LOW STRATUS DECK AT KRIW AND KLND THIS
MORNING. EDGES HAVE BEEN SLOW TO ERODE. HAVE BACKED OFF THE
DISSIPATION OF THE STRATUS UNTIL 19Z-20Z. MORE SUNSHINE HAS BEEN
STARTING TO SHOW THROUGH SINCE 17Z. OTHER TERMINALS WILL BE VFR
THROUGH THIS AFTERNOON. ANOTHER SURGE OF COLD AIR WILL BRING A
RETURN OF LOW CLOUDS AND MVFR OR LOW VFR CEILINGS OVER NORTHERN
WYOMING BETWEEN 00Z-06Z/SAT. THIS AREA OF CLOUDS AND LIGHT SNOW WILL
PUSH SOUTH THROUGH THE NIGHT. KWRL IS THE LEAST LIKELY OF THE
TERMINALS TO SEE AN EXTENDED PERIOD OF LIGHT SNOW. BEST CHANCE FOR
MVFR VISIBILITIES THROUGH 18Z/SAT WILL BE FROM KLND-KCPR WHERE WEAK
UPSLOPE WOULD BE FAVORABLE AFTER THE COLD FRONT PUSHES SOUTH.

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

AREAS OF LOW CLOUDS AND LIGHT SNOW ACROSS PORTIONS OF THE FAR WEST
MOUNTAINS AND VALLEYS THIS MORNING. IFR/MVFR CONDITIONS AT KJAC ARE
LIKELY TO HANG ON THROUGH ABOUT 00Z/SAT. EXPECT THAT WHILE
VISIBILITIES WILL IMPROVE CEILINGS WILL BE MVFR OR LOW VFR THROUGH
THE FORECAST PERIOD. MVFR STRATUS DECK WILL LIFT AT KBPI EARLY THIS
AFTERNOON. EXPECT CONDITIONS THERE AND AT KPNA TO REMAIN VFR THROUGH
THE FORECAST PERIOD. SOME PESKY STRATUS AROUND KRKS BUT BELIEVE THE
SUN WILL WIN OUT AND LEAVE VFR THROUGH TODAY. COLD FRONTAL SURGE
WILL BRING GUSTY EAST-NORTHEAST WIND TO KRKS BEGINNING BETWEEN
09Z/SAT AND 12Z/SAT. WHILE CONDITIONS WILL BE VFR THROUGH
18Z/SAT...POSSIBLE RETURN TO MVFR CONDITIONS WITH SNOW/WIND
COMBINATION BY 00Z/SUN OR SHORTLY THEREAFTER. WILL BE ADDRESSING
THIS MORE WITH THE 00Z TAF SET THIS AFTERNOON.

&&

.FIRE WEATHER...

A SOMEWHAT BUSY FORECAST PERIOD ACROSS THE AREA. SHOWER ACTIVITY
WILL REMAIN POSSIBLE OVER THE NORTHERN THIRD OF THE AREA AS A
DISTURBANCES MOVES ACROSS THE AREA IN THE CONTINUED NORTHWEST FLOW.
AFTER A VERY SLIGHT WARMING TODAY...TEMPERATURES WILL AGAIN COOL
SATURDAY AS AN AREA OF LOW PRESSURE MOVES SOUTH ALONG THE PACIFIC
COASTLINE. AS THIS SYSTEM PROGRESSES...IT WILL SPREAD ADDITIONAL
SHOWERS ACROSS SOUTHWESTERN WYOMING...WITH SOUTHERN WYOMING
EXPERIENCING THE BRUNT OF THE SHOWER ACTIVITY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...PS
AVIATION...CNJ
FIRE WEATHER...BRANHAM





000
FXUS65 KRIW 271741
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1041 AM MST FRI FEB 27 2015

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT

A PUSH OF MOISTURE MOVING IN THE NORTHWEST FLOW WILL KEEP SOME LIGHT
SHOWER ACTIVITY ACROSS NORTHWESTERN WYOMING TODAY. THE VERY WEAK
DISTURBANCE USHERING THIS MOISTURE PUSH WILL CONTINUE TO MOVE EAST
THROUGH THE FORECAST AREA OVERNIGHT. THE MOISTURE IS EXPECTED TO
INCREASE AND SPREAD ACROSS THE NORTHERN THIRD OF THE FORECAST AREA
BY SATURDAY MORNING. TEMPERATURES WILL BE ABLE TO WARM
SLIGHTLY...THOUGH WILL STILL REMAIN COOL.

AN AREA OF LOW PRESSURE OVER THE PACIFIC NORTHWEST WILL DIVE SOUTH
ON SATURDAY...ARRIVING OVER CALIFORNIA SATURDAY. AS THIS SYSTEM
MOVES SOUTH IT WILL BRING COOLING TEMPERATURES...AND SEND ADDITIONAL
PULSES OF MOISTURE OVER THE FORECAST AREA. THE BEST OF THESE PULSES
IS NOT EXPECTED TO ARRIVE UNTIL LATE SATURDAY AFTERNOON...AND WILL
PRIMARILY IMPACT SOUTHWESTERN WYOMING. THIS SYSTEM WILL CONTINUE TO
MOVE SOUTH THROUGH SUNDAY WITH PRECIPITATION LINGERING OVER SOUTHERN
WYOMING THROUGH SUNDAY AFTERNOON. A BRIEF PERIOD OF DRY CONDITIONS
POSSIBLE SUNDAY NIGHT...THOUGH MODELS DO INDICATE THE POTENTIAL FOR
ADDITIONAL MOISTURE ACROSS SOUTHERN WYOMING DURING THE LATE EVENING
HOURS OF SUNDAY.

.LONG TERM...MONDAY THROUGH FRIDAY

MAIN CHANGE FOR TONIGHT ARE THE MODELS NOT SHOWING AS MUCH ENERGY
DIGGING INTO THE GREAT BASIN/INTER-MOUNTAIN WEST MONDAY NIGHT AND
TUESDAY AS LAST NIGHT. MORE SHEARING OR JUST OVERALL LESS ENERGY.
THE SYSTEM THE MODELS TRACK FROM KAMCHATKA YESTERDAY IS STILL THE
SAME BUT THE END SOLUTION IS JUST DIFFERENT. STILL LOOKS LIKE SNOW
SPREADING S AND SE ACROSS THE AREA MONDAY NIGHT INTO EARLY TUESDAY
AND TURNING SHARPLY COLDER. SOME FAIRLY DECENT QG FORCING MAY
COMBINE WITH SOME INITIAL RRQ JET DYNAMICS MONDAY NIGHT AND THEN
LEFT EXIT REGION ON TUE WITH THE NEXT JET APPROACHING. WITH LESS
ENERGY TO THE WEST...MOVEMENT IS FASTER AND NOW WE MAY ACTUALLY
CLEAR BY WEDNESDAY MORNING LEADING TO SOME BITTER COLD LOWS. A
COLD COUPLE DAYS THOUGH FOR TUE AND WED. ON THE PLUS SIDE...THE
RIDGE FLATTENS MORE QUICKLY WITH A RATHER FAST MODERATION THURSDAY
INTO FRIDAY ON THE GFS. BACK TRACKING A LITTLE...THE WEEKEND
SYSTEM ENERGY LINGERS JUST TO THE SOUTH TO START THIS PERIOD
MONDAY WITH CONTINUED POTENTIAL FOR CLOUDS AND MAYBE EVEN SOME
VERY LIGHT PCPN IN OUR FAR SRN ZONES. OTHERWISE... DETERIORATING
CONDS BEGINNING LATER MONDAY ONWARD WITH OUR AFOREMENTIONED MONDAY
NIGHT/TUE SYSTEM FAST APPROACHING. RIGHT AT THE END OF THE MEDIUM
RANGE PERIOD...THE MODELS DIVERGE AS TO THE HANDLING OF A PIECE OF
ENERGY CURRENTLY COMING OFF THE ASIA COAST. THE GFS BRINGS IT
FURTHER OVER THE RIDGE AND INTO THE NRN PLAINS WHILE THE EURO
BRINGS THIS SHORTWAVE AT A LITTLE LOWER LATITUDE ALLOWING IT TO
DIG SE INTO OUR AREA NEXT FRIDAY NIGHT. KEEPING IT DRY FOR NOW.
THE GFS WOULD HAVE A MUCH NICER DAY ON FRIDAY WHILE THE ECMWF IS
ALREADY DIGGING THE LOW TOWARDS US WITH FALLING TEMPS BEHIND A
COLD FRONT.

&&

.AVIATION.../18Z ISSUANCE/

FREQUENT MOUNTAIN OBSCURATIONS ALONG AND WEST OF THE CONTINENTAL
DIVIDE THROUGH THE FORECAST PERIOD. ALSO...FOOTHILL OBSCURATIONS IN
THE VICINITY OF KLND AND KRIW WILL DISSIPATE EARLY THIS AFTERNOON.
EXPECT MORE WIDESPREAD OBSCURATIONS DEVELOPING FROM NORTH TO SOUTH
AFTER 03Z/SAT THROUGH 09Z/SAT.

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

IFR/MVFR CONDITIONS WITH LOW STRATUS DECK AT KRIW AND KLND THIS
MORNING. EDGES HAVE BEEN SLOW TO ERODE. HAVE BACKED OFF THE
DISSIPATION OF THE STRATUS UNTIL 19Z-20Z. MORE SUNSHINE HAS BEEN
STARTING TO SHOW THROUGH SINCE 17Z. OTHER TERMINALS WILL BE VFR
THROUGH THIS AFTERNOON. ANOTHER SURGE OF COLD AIR WILL BRING A
RETURN OF LOW CLOUDS AND MVFR OR LOW VFR CEILINGS OVER NORTHERN
WYOMING BETWEEN 00Z-06Z/SAT. THIS AREA OF CLOUDS AND LIGHT SNOW WILL
PUSH SOUTH THROUGH THE NIGHT. KWRL IS THE LEAST LIKELY OF THE
TERMINALS TO SEE AN EXTENDED PERIOD OF LIGHT SNOW. BEST CHANCE FOR
MVFR VISIBILITIES THROUGH 18Z/SAT WILL BE FROM KLND-KCPR WHERE WEAK
UPSLOPE WOULD BE FAVORABLE AFTER THE COLD FRONT PUSHES SOUTH.

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

AREAS OF LOW CLOUDS AND LIGHT SNOW ACROSS PORTIONS OF THE FAR WEST
MOUNTAINS AND VALLEYS THIS MORNING. IFR/MVFR CONDITIONS AT KJAC ARE
LIKELY TO HANG ON THROUGH ABOUT 00Z/SAT. EXPECT THAT WHILE
VISIBILITIES WILL IMPROVE CEILINGS WILL BE MVFR OR LOW VFR THROUGH
THE FORECAST PERIOD. MVFR STRATUS DECK WILL LIFT AT KBPI EARLY THIS
AFTERNOON. EXPECT CONDITIONS THERE AND AT KPNA TO REMAIN VFR THROUGH
THE FORECAST PERIOD. SOME PESKY STRATUS AROUND KRKS BUT BELIEVE THE
SUN WILL WIN OUT AND LEAVE VFR THROUGH TODAY. COLD FRONTAL SURGE
WILL BRING GUSTY EAST-NORTHEAST WIND TO KRKS BEGINNING BETWEEN
09Z/SAT AND 12Z/SAT. WHILE CONDITIONS WILL BE VFR THROUGH
18Z/SAT...POSSIBLE RETURN TO MVFR CONDITIONS WITH SNOW/WIND
COMBINATION BY 00Z/SUN OR SHORTLY THEREAFTER. WILL BE ADDRESSING
THIS MORE WITH THE 00Z TAF SET THIS AFTERNOON.

&&

.FIRE WEATHER...

A SOMEWHAT BUSY FORECAST PERIOD ACROSS THE AREA. SHOWER ACTIVITY
WILL REMAIN POSSIBLE OVER THE NORTHERN THIRD OF THE AREA AS A
DISTURBANCES MOVES ACROSS THE AREA IN THE CONTINUED NORTHWEST FLOW.
AFTER A VERY SLIGHT WARMING TODAY...TEMPERATURES WILL AGAIN COOL
SATURDAY AS AN AREA OF LOW PRESSURE MOVES SOUTH ALONG THE PACIFIC
COASTLINE. AS THIS SYSTEM PROGRESSES...IT WILL SPREAD ADDITIONAL
SHOWERS ACROSS SOUTHWESTERN WYOMING...WITH SOUTHERN WYOMING
EXPERIENCING THE BRUNT OF THE SHOWER ACTIVITY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...PS
AVIATION...CNJ
FIRE WEATHER...BRANHAM





000
FXUS65 KRIW 271741
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1041 AM MST FRI FEB 27 2015

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT

A PUSH OF MOISTURE MOVING IN THE NORTHWEST FLOW WILL KEEP SOME LIGHT
SHOWER ACTIVITY ACROSS NORTHWESTERN WYOMING TODAY. THE VERY WEAK
DISTURBANCE USHERING THIS MOISTURE PUSH WILL CONTINUE TO MOVE EAST
THROUGH THE FORECAST AREA OVERNIGHT. THE MOISTURE IS EXPECTED TO
INCREASE AND SPREAD ACROSS THE NORTHERN THIRD OF THE FORECAST AREA
BY SATURDAY MORNING. TEMPERATURES WILL BE ABLE TO WARM
SLIGHTLY...THOUGH WILL STILL REMAIN COOL.

AN AREA OF LOW PRESSURE OVER THE PACIFIC NORTHWEST WILL DIVE SOUTH
ON SATURDAY...ARRIVING OVER CALIFORNIA SATURDAY. AS THIS SYSTEM
MOVES SOUTH IT WILL BRING COOLING TEMPERATURES...AND SEND ADDITIONAL
PULSES OF MOISTURE OVER THE FORECAST AREA. THE BEST OF THESE PULSES
IS NOT EXPECTED TO ARRIVE UNTIL LATE SATURDAY AFTERNOON...AND WILL
PRIMARILY IMPACT SOUTHWESTERN WYOMING. THIS SYSTEM WILL CONTINUE TO
MOVE SOUTH THROUGH SUNDAY WITH PRECIPITATION LINGERING OVER SOUTHERN
WYOMING THROUGH SUNDAY AFTERNOON. A BRIEF PERIOD OF DRY CONDITIONS
POSSIBLE SUNDAY NIGHT...THOUGH MODELS DO INDICATE THE POTENTIAL FOR
ADDITIONAL MOISTURE ACROSS SOUTHERN WYOMING DURING THE LATE EVENING
HOURS OF SUNDAY.

.LONG TERM...MONDAY THROUGH FRIDAY

MAIN CHANGE FOR TONIGHT ARE THE MODELS NOT SHOWING AS MUCH ENERGY
DIGGING INTO THE GREAT BASIN/INTER-MOUNTAIN WEST MONDAY NIGHT AND
TUESDAY AS LAST NIGHT. MORE SHEARING OR JUST OVERALL LESS ENERGY.
THE SYSTEM THE MODELS TRACK FROM KAMCHATKA YESTERDAY IS STILL THE
SAME BUT THE END SOLUTION IS JUST DIFFERENT. STILL LOOKS LIKE SNOW
SPREADING S AND SE ACROSS THE AREA MONDAY NIGHT INTO EARLY TUESDAY
AND TURNING SHARPLY COLDER. SOME FAIRLY DECENT QG FORCING MAY
COMBINE WITH SOME INITIAL RRQ JET DYNAMICS MONDAY NIGHT AND THEN
LEFT EXIT REGION ON TUE WITH THE NEXT JET APPROACHING. WITH LESS
ENERGY TO THE WEST...MOVEMENT IS FASTER AND NOW WE MAY ACTUALLY
CLEAR BY WEDNESDAY MORNING LEADING TO SOME BITTER COLD LOWS. A
COLD COUPLE DAYS THOUGH FOR TUE AND WED. ON THE PLUS SIDE...THE
RIDGE FLATTENS MORE QUICKLY WITH A RATHER FAST MODERATION THURSDAY
INTO FRIDAY ON THE GFS. BACK TRACKING A LITTLE...THE WEEKEND
SYSTEM ENERGY LINGERS JUST TO THE SOUTH TO START THIS PERIOD
MONDAY WITH CONTINUED POTENTIAL FOR CLOUDS AND MAYBE EVEN SOME
VERY LIGHT PCPN IN OUR FAR SRN ZONES. OTHERWISE... DETERIORATING
CONDS BEGINNING LATER MONDAY ONWARD WITH OUR AFOREMENTIONED MONDAY
NIGHT/TUE SYSTEM FAST APPROACHING. RIGHT AT THE END OF THE MEDIUM
RANGE PERIOD...THE MODELS DIVERGE AS TO THE HANDLING OF A PIECE OF
ENERGY CURRENTLY COMING OFF THE ASIA COAST. THE GFS BRINGS IT
FURTHER OVER THE RIDGE AND INTO THE NRN PLAINS WHILE THE EURO
BRINGS THIS SHORTWAVE AT A LITTLE LOWER LATITUDE ALLOWING IT TO
DIG SE INTO OUR AREA NEXT FRIDAY NIGHT. KEEPING IT DRY FOR NOW.
THE GFS WOULD HAVE A MUCH NICER DAY ON FRIDAY WHILE THE ECMWF IS
ALREADY DIGGING THE LOW TOWARDS US WITH FALLING TEMPS BEHIND A
COLD FRONT.

&&

.AVIATION.../18Z ISSUANCE/

FREQUENT MOUNTAIN OBSCURATIONS ALONG AND WEST OF THE CONTINENTAL
DIVIDE THROUGH THE FORECAST PERIOD. ALSO...FOOTHILL OBSCURATIONS IN
THE VICINITY OF KLND AND KRIW WILL DISSIPATE EARLY THIS AFTERNOON.
EXPECT MORE WIDESPREAD OBSCURATIONS DEVELOPING FROM NORTH TO SOUTH
AFTER 03Z/SAT THROUGH 09Z/SAT.

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

IFR/MVFR CONDITIONS WITH LOW STRATUS DECK AT KRIW AND KLND THIS
MORNING. EDGES HAVE BEEN SLOW TO ERODE. HAVE BACKED OFF THE
DISSIPATION OF THE STRATUS UNTIL 19Z-20Z. MORE SUNSHINE HAS BEEN
STARTING TO SHOW THROUGH SINCE 17Z. OTHER TERMINALS WILL BE VFR
THROUGH THIS AFTERNOON. ANOTHER SURGE OF COLD AIR WILL BRING A
RETURN OF LOW CLOUDS AND MVFR OR LOW VFR CEILINGS OVER NORTHERN
WYOMING BETWEEN 00Z-06Z/SAT. THIS AREA OF CLOUDS AND LIGHT SNOW WILL
PUSH SOUTH THROUGH THE NIGHT. KWRL IS THE LEAST LIKELY OF THE
TERMINALS TO SEE AN EXTENDED PERIOD OF LIGHT SNOW. BEST CHANCE FOR
MVFR VISIBILITIES THROUGH 18Z/SAT WILL BE FROM KLND-KCPR WHERE WEAK
UPSLOPE WOULD BE FAVORABLE AFTER THE COLD FRONT PUSHES SOUTH.

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

AREAS OF LOW CLOUDS AND LIGHT SNOW ACROSS PORTIONS OF THE FAR WEST
MOUNTAINS AND VALLEYS THIS MORNING. IFR/MVFR CONDITIONS AT KJAC ARE
LIKELY TO HANG ON THROUGH ABOUT 00Z/SAT. EXPECT THAT WHILE
VISIBILITIES WILL IMPROVE CEILINGS WILL BE MVFR OR LOW VFR THROUGH
THE FORECAST PERIOD. MVFR STRATUS DECK WILL LIFT AT KBPI EARLY THIS
AFTERNOON. EXPECT CONDITIONS THERE AND AT KPNA TO REMAIN VFR THROUGH
THE FORECAST PERIOD. SOME PESKY STRATUS AROUND KRKS BUT BELIEVE THE
SUN WILL WIN OUT AND LEAVE VFR THROUGH TODAY. COLD FRONTAL SURGE
WILL BRING GUSTY EAST-NORTHEAST WIND TO KRKS BEGINNING BETWEEN
09Z/SAT AND 12Z/SAT. WHILE CONDITIONS WILL BE VFR THROUGH
18Z/SAT...POSSIBLE RETURN TO MVFR CONDITIONS WITH SNOW/WIND
COMBINATION BY 00Z/SUN OR SHORTLY THEREAFTER. WILL BE ADDRESSING
THIS MORE WITH THE 00Z TAF SET THIS AFTERNOON.

&&

.FIRE WEATHER...

A SOMEWHAT BUSY FORECAST PERIOD ACROSS THE AREA. SHOWER ACTIVITY
WILL REMAIN POSSIBLE OVER THE NORTHERN THIRD OF THE AREA AS A
DISTURBANCES MOVES ACROSS THE AREA IN THE CONTINUED NORTHWEST FLOW.
AFTER A VERY SLIGHT WARMING TODAY...TEMPERATURES WILL AGAIN COOL
SATURDAY AS AN AREA OF LOW PRESSURE MOVES SOUTH ALONG THE PACIFIC
COASTLINE. AS THIS SYSTEM PROGRESSES...IT WILL SPREAD ADDITIONAL
SHOWERS ACROSS SOUTHWESTERN WYOMING...WITH SOUTHERN WYOMING
EXPERIENCING THE BRUNT OF THE SHOWER ACTIVITY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...PS
AVIATION...CNJ
FIRE WEATHER...BRANHAM






000
FXUS63 KUNR 271728
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1028 AM MST FRI FEB 27 2015

.SHORT TERM...TODAY THROUGH SATURDAY NIGHT
ISSUED AT 306 AM MST FRI FEB 27 2015

UPPER LEVEL ANALYSIS HAS BROAD TROF ACROSS THE NORTHERN CONUS WITH
LIGHT NORTH TO NORTHWEST FLOW ACROSS THE NORTHERN PLAINS. SKIES
ARE MAINLY CLEAR ACROSS THE AREA WITH SOME LOW TO MID LEVEL CLOUDS
ACROSS PARTS OF NORTHEAST WYOMING AND FAR SOUTHWEST SOUTH DAKOTA.
AT THE SURFACE...ARCTIC HIGH IS LOCATED ACROSS THE CENTRAL AND
NORTHERN PLAINS...WITH LIGHT WINDS AND VERY COLD TEMPERATURES.
TEMPS AT 3AM RANGE FROM 10 BELOW ZERO TO A FEW DEGREES ABOVE ZERO
ACROSS THE AREA.

TODAY...BROAD UPPER TROF REMAINS OVER THE AREA WITH LIGHT
NORTHERLY UPPER FLOW CONTINUING. ARCTIC SURFACE HIGH SHIFTS A
LITTLE FURTHER SOUTH AND EAST...WITH RETURN FLOW STRENGTHENING
ACROSS THE AREA TODAY. BREEZY SOUTHERLY WINDS WILL PERSIST ACROSS
NORTHEAST WYOMING THROUGH EARLY AFTERNOON...BEFORE SUBSIDING A
BIT. LIGHT WINDS ACROSS THE SOUTH DAKOTA PLAINS WILL BECOME
SOUTHERLY THIS MORNING AND THEN INCREASE TO 15 TO 25 MPH BY
AFTERNOON. IN ADDITION...THE SOUTHERLY BOUNDARY LAYER FLOW WILL
BRING SLIGHTLY WARMER AIR INTO THE REGION. HIGH TEMPERATURES WILL
SLOWLY CLIMB INTO THE TEENS TO LOWER 20S TODAY...TAKING MOST OF
THE DAY TO REACH THEIR MAX LEVELS. SKIES SHOULD BE MOSTLY SUNNY.

TONIGHT...ARCTIC SURFACE HIGH SHIFTS FURTHER SOUTHEAST AS A WEAK
TROF OF LOW PRESSURE DEVELOPS ACROSS MONTANA. STRONG SOUTHERLY
RETURN FLOW DURING THE EVENING HOURS ACROSS THE SOUTH DAKOTA
PLAINS WILL DIMINISH QUICKLY IN THE EVENING AS A WEAK SURFACE TROF
SHIFTS INTO WESTERN SOUTH DAKOTA AFTER MIDNIGHT. SLIGHTLY MILDER
AIR WILL CONTINUE TO MOVE INTO THE AREA...WITH LOW TEMPERATURES
ONLY FALLING INTO THE SINGLE DIGITS AND TEENS ABOVE ZERO. SKIES
SHOULD REMAIN MOSTLY CLEAR.

SATURDAY...UPPER TROF REMAINS ACROSS THE NORTHERN PLAINS AS LOW
CLOSES OFF IN THE SW CONUS. WEAK SURFACE TROF CONTINUES TO SLOWLY
SHIFT EAST...WITH WINDS SHIFTING TO THE NORTHWEST AS TROF PASSES.
TEMPERATURES WILL BE SIMILAR TO FRIDAY...WITH POSSIBLY SOME LOW
30S ACROSS THE SOUTHERN SOUTH DAKOTA PLAINS IN THE VICINITY OF THE
SURFACE TROF. COOL TEMPERATURES REMAIN ACROSS THE AREA...WITH
LOWS FALLING INTO THE SINGLE DIGITS AND TEENS.

.LONG TERM...SUNDAY THROUGH THURSDAY
ISSUED AT 306 AM MST FRI FEB 27 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE ON SUNDAY AS A DRY
UPPER TROUGH AND A SURFACE HIGH REMAIN OVER THE REGION. THE
SURFACE HIGH WILL MOVE EAST ON MONDAY AS THE UPPER FLOW BECOMES
MORE WESTERLY AND WARMER PACIFIC SOURCED AIR SPREADS OVER THE
NORTHERN PLAINS. THIS WILL LEAD TO A BRIEF WARMUP...WITH NEAR
AVERAGE TEMPERATURES ON MONDAY. A LARGE LOW PRESSURE SYSTEM WILL
CROSS THE CNTRL PLAINS ON TUESDAY WHICH WILL CAUSE ARCTIC AIR TO
BE DRAWN SOUTHWARD INTO THE NORTHERN PLAINS. TUESDAY HIGH TEMPS
WILL ONLY REACH THE MID TEENS TO MID 20S. THE UPPER TROUGH WILL
ALSO BRING A CHANCE OF SNOW TO MUCH OF THE AREA TUESDAY/TUESDAY
NIGHT. DRY WEATHER IS EXPECTED WEDNESDAY WITH CONTINUED VERY COLD
TEMPERATURES AS THE ARCTIC HIGH CROSSES THE FORECAST AREA. WARMER
AND CONTINUED DRY WEATHER IS EXPECTED FOR THE REST OF THE WEEK AS
A STRONG UPPER RIDGE BUILDS TO THE WEST OF THE FORECAST AREA.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY)
ISSUED AT 1028 AM MST FRI FEB 27 2015

VFR CONDITIONS WILL OCCUR OVER MOST OF THE AREA TODAY THROUGH
TONIGHT. THE EXCEPTION IS FOR LCL IFR AND SCT MVFR CIGS OVER NERN
WY AND FAR SWRN SD THROUGH EARLY AFTN...WHERE STRONG SLY FLOW WAS
ADVECTING LOW-LEVEL MOISTURE NWD. OTHERWISE...AREAS OF MVFR CIGS
WILL DEVELOP EARLY THIS EVENING OVER NERN WY WITH COVERAGE OF MVFR
CIGS INCREASING AFTER 06Z. THE NAM MOS APPEARED TOO AGGRESSIVE WITH
LOW CLOUDS RELATIVE TO THE GFS MOS...SO HAVE TRENDED THE KGCC CIGS
HIGHER THAN THAT GIVEN BY THE PESSIMISTIC NAM MOS.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...15
LONG TERM...10
AVIATION...BUNKERS









000
FXUS63 KUNR 271728
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1028 AM MST FRI FEB 27 2015

.SHORT TERM...TODAY THROUGH SATURDAY NIGHT
ISSUED AT 306 AM MST FRI FEB 27 2015

UPPER LEVEL ANALYSIS HAS BROAD TROF ACROSS THE NORTHERN CONUS WITH
LIGHT NORTH TO NORTHWEST FLOW ACROSS THE NORTHERN PLAINS. SKIES
ARE MAINLY CLEAR ACROSS THE AREA WITH SOME LOW TO MID LEVEL CLOUDS
ACROSS PARTS OF NORTHEAST WYOMING AND FAR SOUTHWEST SOUTH DAKOTA.
AT THE SURFACE...ARCTIC HIGH IS LOCATED ACROSS THE CENTRAL AND
NORTHERN PLAINS...WITH LIGHT WINDS AND VERY COLD TEMPERATURES.
TEMPS AT 3AM RANGE FROM 10 BELOW ZERO TO A FEW DEGREES ABOVE ZERO
ACROSS THE AREA.

TODAY...BROAD UPPER TROF REMAINS OVER THE AREA WITH LIGHT
NORTHERLY UPPER FLOW CONTINUING. ARCTIC SURFACE HIGH SHIFTS A
LITTLE FURTHER SOUTH AND EAST...WITH RETURN FLOW STRENGTHENING
ACROSS THE AREA TODAY. BREEZY SOUTHERLY WINDS WILL PERSIST ACROSS
NORTHEAST WYOMING THROUGH EARLY AFTERNOON...BEFORE SUBSIDING A
BIT. LIGHT WINDS ACROSS THE SOUTH DAKOTA PLAINS WILL BECOME
SOUTHERLY THIS MORNING AND THEN INCREASE TO 15 TO 25 MPH BY
AFTERNOON. IN ADDITION...THE SOUTHERLY BOUNDARY LAYER FLOW WILL
BRING SLIGHTLY WARMER AIR INTO THE REGION. HIGH TEMPERATURES WILL
SLOWLY CLIMB INTO THE TEENS TO LOWER 20S TODAY...TAKING MOST OF
THE DAY TO REACH THEIR MAX LEVELS. SKIES SHOULD BE MOSTLY SUNNY.

TONIGHT...ARCTIC SURFACE HIGH SHIFTS FURTHER SOUTHEAST AS A WEAK
TROF OF LOW PRESSURE DEVELOPS ACROSS MONTANA. STRONG SOUTHERLY
RETURN FLOW DURING THE EVENING HOURS ACROSS THE SOUTH DAKOTA
PLAINS WILL DIMINISH QUICKLY IN THE EVENING AS A WEAK SURFACE TROF
SHIFTS INTO WESTERN SOUTH DAKOTA AFTER MIDNIGHT. SLIGHTLY MILDER
AIR WILL CONTINUE TO MOVE INTO THE AREA...WITH LOW TEMPERATURES
ONLY FALLING INTO THE SINGLE DIGITS AND TEENS ABOVE ZERO. SKIES
SHOULD REMAIN MOSTLY CLEAR.

SATURDAY...UPPER TROF REMAINS ACROSS THE NORTHERN PLAINS AS LOW
CLOSES OFF IN THE SW CONUS. WEAK SURFACE TROF CONTINUES TO SLOWLY
SHIFT EAST...WITH WINDS SHIFTING TO THE NORTHWEST AS TROF PASSES.
TEMPERATURES WILL BE SIMILAR TO FRIDAY...WITH POSSIBLY SOME LOW
30S ACROSS THE SOUTHERN SOUTH DAKOTA PLAINS IN THE VICINITY OF THE
SURFACE TROF. COOL TEMPERATURES REMAIN ACROSS THE AREA...WITH
LOWS FALLING INTO THE SINGLE DIGITS AND TEENS.

.LONG TERM...SUNDAY THROUGH THURSDAY
ISSUED AT 306 AM MST FRI FEB 27 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE ON SUNDAY AS A DRY
UPPER TROUGH AND A SURFACE HIGH REMAIN OVER THE REGION. THE
SURFACE HIGH WILL MOVE EAST ON MONDAY AS THE UPPER FLOW BECOMES
MORE WESTERLY AND WARMER PACIFIC SOURCED AIR SPREADS OVER THE
NORTHERN PLAINS. THIS WILL LEAD TO A BRIEF WARMUP...WITH NEAR
AVERAGE TEMPERATURES ON MONDAY. A LARGE LOW PRESSURE SYSTEM WILL
CROSS THE CNTRL PLAINS ON TUESDAY WHICH WILL CAUSE ARCTIC AIR TO
BE DRAWN SOUTHWARD INTO THE NORTHERN PLAINS. TUESDAY HIGH TEMPS
WILL ONLY REACH THE MID TEENS TO MID 20S. THE UPPER TROUGH WILL
ALSO BRING A CHANCE OF SNOW TO MUCH OF THE AREA TUESDAY/TUESDAY
NIGHT. DRY WEATHER IS EXPECTED WEDNESDAY WITH CONTINUED VERY COLD
TEMPERATURES AS THE ARCTIC HIGH CROSSES THE FORECAST AREA. WARMER
AND CONTINUED DRY WEATHER IS EXPECTED FOR THE REST OF THE WEEK AS
A STRONG UPPER RIDGE BUILDS TO THE WEST OF THE FORECAST AREA.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY)
ISSUED AT 1028 AM MST FRI FEB 27 2015

VFR CONDITIONS WILL OCCUR OVER MOST OF THE AREA TODAY THROUGH
TONIGHT. THE EXCEPTION IS FOR LCL IFR AND SCT MVFR CIGS OVER NERN
WY AND FAR SWRN SD THROUGH EARLY AFTN...WHERE STRONG SLY FLOW WAS
ADVECTING LOW-LEVEL MOISTURE NWD. OTHERWISE...AREAS OF MVFR CIGS
WILL DEVELOP EARLY THIS EVENING OVER NERN WY WITH COVERAGE OF MVFR
CIGS INCREASING AFTER 06Z. THE NAM MOS APPEARED TOO AGGRESSIVE WITH
LOW CLOUDS RELATIVE TO THE GFS MOS...SO HAVE TRENDED THE KGCC CIGS
HIGHER THAN THAT GIVEN BY THE PESSIMISTIC NAM MOS.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...15
LONG TERM...10
AVIATION...BUNKERS








000
FXUS63 KUNR 271100
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
400 AM MST FRI FEB 27 2015

.SHORT TERM...TODAY THROUGH SATURDAY NIGHT
ISSUED AT 306 AM MST FRI FEB 27 2015

UPPER LEVEL ANALYSIS HAS BROAD TROF ACROSS THE NORTHERN CONUS WITH
LIGHT NORTH TO NORTHWEST FLOW ACROSS THE NORTHERN PLAINS. SKIES
ARE MAINLY CLEAR ACROSS THE AREA WITH SOME LOW TO MID LEVEL CLOUDS
ACROSS PARTS OF NORTHEAST WYOMING AND FAR SOUTHWEST SOUTH DAKOTA.
AT THE SURFACE...ARCTIC HIGH IS LOCATED ACROSS THE CENTRAL AND
NORTHERN PLAINS...WITH LIGHT WINDS AND VERY COLD TEMPERATURES.
TEMPS AT 3AM RANGE FROM 10 BELOW ZERO TO A FEW DEGREES ABOVE ZERO
ACROSS THE AREA.

TODAY...BROAD UPPER TROF REMAINS OVER THE AREA WITH LIGHT
NORTHERLY UPPER FLOW CONTINUING. ARCTIC SURFACE HIGH SHIFTS A
LITTLE FURTHER SOUTH AND EAST...WITH RETURN FLOW STRENGTHENING
ACROSS THE AREA TODAY. BREEZY SOUTHERLY WINDS WILL PERSIST ACROSS
NORTHEAST WYOMING THROUGH EARLY AFTERNOON...BEFORE SUBSIDING A
BIT. LIGHT WINDS ACROSS THE SOUTH DAKOTA PLAINS WILL BECOME
SOUTHERLY THIS MORNING AND THEN INCREASE TO 15 TO 25 MPH BY
AFTERNOON. IN ADDITION...THE SOUTHERLY BOUNDARY LAYER FLOW WILL
BRING SLIGHTLY WARMER AIR INTO THE REGION. HIGH TEMPERATURES WILL
SLOWLY CLIMB INTO THE TEENS TO LOWER 20S TODAY...TAKING MOST OF
THE DAY TO REACH THEIR MAX LEVELS. SKIES SHOULD BE MOSTLY SUNNY.

TONIGHT...ARCTIC SURFACE HIGH SHIFTS FURTHER SOUTHEAST AS A WEAK
TROF OF LOW PRESSURE DEVELOPS ACROSS MONTANA. STRONG SOUTHERLY
RETURN FLOW DURING THE EVENING HOURS ACROSS THE SOUTH DAKOTA
PLAINS WILL DIMINISH QUICKLY IN THE EVENING AS A WEAK SURFACE TROF
SHIFTS INTO WESTERN SOUTH DAKOTA AFTER MIDNIGHT. SLIGHTLY MILDER
AIR WILL CONTINUE TO MOVE INTO THE AREA...WITH LOW TEMPERATURES
ONLY FALLING INTO THE SINGLE DIGITS AND TEENS ABOVE ZERO. SKIES
SHOULD REMAIN MOSTLY CLEAR.

SATURDAY...UPPER TROF REMAINS ACROSS THE NORTHERN PLAINS AS LOW
CLOSES OFF IN THE SW CONUS. WEAK SURFACE TROF CONTINUES TO SLOWLY
SHIFT EAST...WITH WINDS SHIFTING TO THE NORTHWEST AS TROF PASSES.
TEMPERATURES WILL BE SIMILAR TO FRIDAY...WITH POSSIBLY SOME LOW
30S ACROSS THE SOUTHERN SOUTH DAKOTA PLAINS IN THE VICINITY OF THE
SURFACE TROF. COOL TEMPERATURES REMAIN ACROSS THE AREA...WITH
LOWS FALLING INTO THE SINGLE DIGITS AND TEENS.

.LONG TERM...SUNDAY THROUGH THURSDAY
ISSUED AT 306 AM MST FRI FEB 27 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE ON SUNDAY AS A DRY
UPPER TROUGH AND A SURFACE HIGH REMAIN OVER THE REGION. THE
SURFACE HIGH WILL MOVE EAST ON MONDAY AS THE UPPER FLOW BECOMES
MORE WESTERLY AND WARMER PACIFIC SOURCED AIR SPREADS OVER THE
NORTHERN PLAINS. THIS WILL LEAD TO A BRIEF WARMUP...WITH NEAR
AVERAGE TEMPERATURES ON MONDAY. A LARGE LOW PRESSURE SYSTEM WILL
CROSS THE CNTRL PLAINS ON TUESDAY WHICH WILL CAUSE ARCTIC AIR TO
BE DRAWN SOUTHWARD INTO THE NORTHERN PLAINS. TUESDAY HIGH TEMPS
WILL ONLY REACH THE MID TEENS TO MID 20S. THE UPPER TROUGH WILL
ALSO BRING A CHANCE OF SNOW TO MUCH OF THE AREA TUESDAY/TUESDAY
NIGHT. DRY WEATHER IS EXPECTED WEDNESDAY WITH CONTINUED VERY COLD
TEMPERATURES AS THE ARCTIC HIGH CROSSES THE FORECAST AREA. WARMER
AND CONTINUED DRY WEATHER IS EXPECTED FOR THE REST OF THE WEEK AS
A STRONG UPPER RIDGE BUILDS TO THE WEST OF THE FORECAST AREA.

&&

.AVIATION...FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING
ISSUED AT 306 AM MST FRI FEB 27 2015

VFR CONDITIONS WILL OCCUR OVER THE AREA TODAY. AREAS OF MVFR CIGS
WILL DEVELOP EARLY THIS EVENING WITH COVERAGE OF MVFR CIGS
BECOMING GREATER DURING THE REST OF THE NIGHT.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...15
LONG TERM...10
AVIATION...10







000
FXUS63 KUNR 271100
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
400 AM MST FRI FEB 27 2015

.SHORT TERM...TODAY THROUGH SATURDAY NIGHT
ISSUED AT 306 AM MST FRI FEB 27 2015

UPPER LEVEL ANALYSIS HAS BROAD TROF ACROSS THE NORTHERN CONUS WITH
LIGHT NORTH TO NORTHWEST FLOW ACROSS THE NORTHERN PLAINS. SKIES
ARE MAINLY CLEAR ACROSS THE AREA WITH SOME LOW TO MID LEVEL CLOUDS
ACROSS PARTS OF NORTHEAST WYOMING AND FAR SOUTHWEST SOUTH DAKOTA.
AT THE SURFACE...ARCTIC HIGH IS LOCATED ACROSS THE CENTRAL AND
NORTHERN PLAINS...WITH LIGHT WINDS AND VERY COLD TEMPERATURES.
TEMPS AT 3AM RANGE FROM 10 BELOW ZERO TO A FEW DEGREES ABOVE ZERO
ACROSS THE AREA.

TODAY...BROAD UPPER TROF REMAINS OVER THE AREA WITH LIGHT
NORTHERLY UPPER FLOW CONTINUING. ARCTIC SURFACE HIGH SHIFTS A
LITTLE FURTHER SOUTH AND EAST...WITH RETURN FLOW STRENGTHENING
ACROSS THE AREA TODAY. BREEZY SOUTHERLY WINDS WILL PERSIST ACROSS
NORTHEAST WYOMING THROUGH EARLY AFTERNOON...BEFORE SUBSIDING A
BIT. LIGHT WINDS ACROSS THE SOUTH DAKOTA PLAINS WILL BECOME
SOUTHERLY THIS MORNING AND THEN INCREASE TO 15 TO 25 MPH BY
AFTERNOON. IN ADDITION...THE SOUTHERLY BOUNDARY LAYER FLOW WILL
BRING SLIGHTLY WARMER AIR INTO THE REGION. HIGH TEMPERATURES WILL
SLOWLY CLIMB INTO THE TEENS TO LOWER 20S TODAY...TAKING MOST OF
THE DAY TO REACH THEIR MAX LEVELS. SKIES SHOULD BE MOSTLY SUNNY.

TONIGHT...ARCTIC SURFACE HIGH SHIFTS FURTHER SOUTHEAST AS A WEAK
TROF OF LOW PRESSURE DEVELOPS ACROSS MONTANA. STRONG SOUTHERLY
RETURN FLOW DURING THE EVENING HOURS ACROSS THE SOUTH DAKOTA
PLAINS WILL DIMINISH QUICKLY IN THE EVENING AS A WEAK SURFACE TROF
SHIFTS INTO WESTERN SOUTH DAKOTA AFTER MIDNIGHT. SLIGHTLY MILDER
AIR WILL CONTINUE TO MOVE INTO THE AREA...WITH LOW TEMPERATURES
ONLY FALLING INTO THE SINGLE DIGITS AND TEENS ABOVE ZERO. SKIES
SHOULD REMAIN MOSTLY CLEAR.

SATURDAY...UPPER TROF REMAINS ACROSS THE NORTHERN PLAINS AS LOW
CLOSES OFF IN THE SW CONUS. WEAK SURFACE TROF CONTINUES TO SLOWLY
SHIFT EAST...WITH WINDS SHIFTING TO THE NORTHWEST AS TROF PASSES.
TEMPERATURES WILL BE SIMILAR TO FRIDAY...WITH POSSIBLY SOME LOW
30S ACROSS THE SOUTHERN SOUTH DAKOTA PLAINS IN THE VICINITY OF THE
SURFACE TROF. COOL TEMPERATURES REMAIN ACROSS THE AREA...WITH
LOWS FALLING INTO THE SINGLE DIGITS AND TEENS.

.LONG TERM...SUNDAY THROUGH THURSDAY
ISSUED AT 306 AM MST FRI FEB 27 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE ON SUNDAY AS A DRY
UPPER TROUGH AND A SURFACE HIGH REMAIN OVER THE REGION. THE
SURFACE HIGH WILL MOVE EAST ON MONDAY AS THE UPPER FLOW BECOMES
MORE WESTERLY AND WARMER PACIFIC SOURCED AIR SPREADS OVER THE
NORTHERN PLAINS. THIS WILL LEAD TO A BRIEF WARMUP...WITH NEAR
AVERAGE TEMPERATURES ON MONDAY. A LARGE LOW PRESSURE SYSTEM WILL
CROSS THE CNTRL PLAINS ON TUESDAY WHICH WILL CAUSE ARCTIC AIR TO
BE DRAWN SOUTHWARD INTO THE NORTHERN PLAINS. TUESDAY HIGH TEMPS
WILL ONLY REACH THE MID TEENS TO MID 20S. THE UPPER TROUGH WILL
ALSO BRING A CHANCE OF SNOW TO MUCH OF THE AREA TUESDAY/TUESDAY
NIGHT. DRY WEATHER IS EXPECTED WEDNESDAY WITH CONTINUED VERY COLD
TEMPERATURES AS THE ARCTIC HIGH CROSSES THE FORECAST AREA. WARMER
AND CONTINUED DRY WEATHER IS EXPECTED FOR THE REST OF THE WEEK AS
A STRONG UPPER RIDGE BUILDS TO THE WEST OF THE FORECAST AREA.

&&

.AVIATION...FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING
ISSUED AT 306 AM MST FRI FEB 27 2015

VFR CONDITIONS WILL OCCUR OVER THE AREA TODAY. AREAS OF MVFR CIGS
WILL DEVELOP EARLY THIS EVENING WITH COVERAGE OF MVFR CIGS
BECOMING GREATER DURING THE REST OF THE NIGHT.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...15
LONG TERM...10
AVIATION...10






000
FXUS65 KCYS 271032
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
332 AM MST FRI FEB 27 2015

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 330 AM MST FRI FEB 27 2015

RADAR IMAGERY SHOWS LIGHT SNOW HAS REALLY LET UP ACROSS LARAMIE
COUNTY WITH ONLY VERY LIGHT SNOW OR FLURRIES. CANCELLED THE WINTER
WEATHER ADVISORY A BIT EARLY WITH MINIMAL ADDITIONAL ACCUMULATION
EXPECTED. COLD WIND CHILLS HAVE BEEN OCCURRING OVER THE SOUTHERN
LARAMIE RANGE WITH VALUES IN THE -20 TO -25 RANGE. WITH NOT MUCH
CHANGE IN THE TEMPS OR WINDS THROUGH SUNRISE...SEE NO REASON THAT
WIND CHILLS WILL REACH WARNING CRITERIA(-30)...HOWEVER WILL CONTINUE
TO MONITOR. SOUTHERLY WINDS WILL PERSIST THROUGH THE AFTN ACROSS
THE PLAINS WITH LOW LEVEL UPSLOPE ALONG THE CHEYENNE RIDGE. ALL
MODELS SHOW LOW CLOUDS BEING QUITE PERSISTENT ALONG THE CHEYENNE
RIDGE AND INTO THE SOUTHERN PANHANDLE THROUGH THE EARLY AFTN WHICH
WILL KEEP TEMPS FROM WARMING TOO MUCH COMPARED TO YESTERDAY. OTHER
AREAS WHERE CLEARING OCCURS WILL WARM 5-10 DEGREES...BUT THAT
STILL PUTS US AROUND 20 DEGREES BELOW NORMAL FOR LATE FEB. PRETTY
QUIET WEATHER FROM THIS EVENING THROUGH MIDDAY SATURDAY. WINDS
WILL BE WEAK AND RADIATIONAL COOLING WILL BE BETTER TONIGHT WITH
LESS LOW CLOUDS PRESENT...SO LOWS WILL ONCE AGAIN FALL INTO THE
SINGLE DIGITS.

ANOTHER LIGHT SNOW EVENT APPEARS POSSIBLE FROM MAINLY SAT AFTN
THROUGH SAT NIGHT. THE 00Z EURO HOWEVER CONTINUES TO BE THE OUTLIER
IN SHOWING ALMOST ALL THE QPF TO THE SOUTH OF THE COLORADO BORDER.
THE NAM HAS COME MORE IN LINE WITH THE CONSISTENTLY WETTER GFS...
SHOWING WIDESPREAD 0.1-0.2 INCHES OVER MUCH OF THE CWA. WITH LOW
LEVEL UPSLOPE AND ISENTROPIC LIFT BEING THE PRIMARY FORCING
MECHANISMS... STILL BELIEVE THAT MOST LOCATIONS WILL ONLY PICK UP
A FEW INCHES AND BEING LARGELY SUB-ADVISORY. WITH WINDS LARGELY
REMAINING BELOW 15 KTS...AREAS OF BLOWING SNOW WILL NOT BE A
CONCERN. PRECIP COMES TO AN END BY LATE SUN MORNING WITH ANOTHER
CHILLY DAY IN STORE.

.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 AM MST FRI FEB 27 2015

00Z MEDIUM RANGE MODELS ARE IN GOOD AGREEMENT PORTRAYING A SPLIT
FLOW ALOFT WITH A MORE PROGRESSIVE NORTHERN STREAM AND SLOWER
SOUTHERN STREAM. WEST-SOUTHWEST FLOW ALOFT AHEAD OF CA/NV TROUGH
WILL ADVECT ABUNDANT PACIFIC MOISTURE ACROSS THE FOUR CORNERS AND
CENTRAL ROCKIES EARLY NEXT WEEK. POTENT NORTHERN STREAM SHORTWAVE
MOVING ACROSS THE NORTHERN ROCKIES WILL PROPEL A ARCTIC COLD FRONT
SOUTHEAST ACROSS THE CWA BY TUESDAY MORNING. PRIOR TO THE FROPA...
A SURFACE LOW OVER THE FOUR CORNERS TRACKS NORTHEAST TO EAST
THROUGH SOUTHERN COLORADO AND KANSAS. POST-FRONTAL UPSLOPE NORTHEAST
LOW LEVEL FLOW...Q-G LIFT FROM RIGHT REAR QUAD OF UPPER JET AND
OVERRUNNING MOISTURE ACROSS A SHALLOW COLD AIR MASS WILL SET THE
STAGE FOR WIDESPREAD ACCUMULATING SNOW TUESDAY. GUSTY NORTH-NORTHEAST
WINDS WILL CREATE AREAS OF BLOWING/DRIFTING SNOW. IT`S EARLY TO
FORECAST SNOW AMOUNTS...BUT THIS SYSTEM WILL BE PROGRESSIVE WITH
SNOW TAPERING OFF FROM NORTHWEST TO SOUTHEAST TUESDAY NIGHT AS
COLD HIGH PRESSURE BUILDS ACROSS THE REGION. TEMPERATURES WILL BE
MILDER AHEAD OF THE FRONT MONDAY BUT AT LEAST 1O DEGREES BELOW
NORMAL. MUCH COLDER TEMPERATURES RETURN TUESDAY AND LAST THROUGH
MIDWEEK WITH HIGHS IN THE TEENS AND LOWS FROM 10 BELOW TO 10 ABOVE
ZERO. IN THE WAKE OF THE MIDWEEK SYSTEM...FLOW ALOFT BACKS FROM
NORTH- NORTHWEST TO MORE ZONAL THURSDAY. WESTERLY 700MB WINDS
PICK UP TO 40 KT THURSDAY RESULTING IN GUSTY DOWNSLOPE WINDS LEE
OF THE FRONT RANGE PUSHING THE MERCURY INTO THE 30S.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 230 AM MST FRI FEB 27 2015

LIGHT-MODERATE UPSLOPE SOUTHEASTERLY WINDS WILL RESULT IN
PREVAILING IFR-LIFR CIGS/VSBYS OVER FAR SOUTHEAST WY INCLUDING
KCYS THROUGH MUCH OF THE DAY. MVFR-IFR CIGS/VSBYS WILL AFFECT
PORTIONS OF THE LARAMIE VALLEY AND MUCH OF WESTERN NE PANHANDLE
THIS MORNING BEFORE SLOW IMPROVEMENT TO VFR THIS AFTERNOON.
CONDITIONS WILL DETERIORATE TO MVFR-IFR THIS EVENING AT KCYS...
KAIA...KSNY AND KBFF WITH LIGHT SOUTHERLY WINDS.

&&

.FIRE WEATHER...
ISSUED AT 245 AM MST FRI FEB 27 2015

NO FIRE WEATHER CONCERNS OVER THE NEXT WEEK. TEMPERATURES WILL
CONTINUE TO REMAIN BELOW NORMAL. WIDESPREAD LIGHT SNOW COULD FALL
SATURDAY AFTERNOON THROUGH THE NIGHT...ESPECIALLY FOR AREAS ALONG
THE COLORADO BORDER.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

SHORT TERM...FINCH
LONG TERM...JAMSKI
AVIATION...JAMSKI
FIRE WEATHER...FINCH



000
FXUS65 KCYS 271032
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
332 AM MST FRI FEB 27 2015

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 330 AM MST FRI FEB 27 2015

RADAR IMAGERY SHOWS LIGHT SNOW HAS REALLY LET UP ACROSS LARAMIE
COUNTY WITH ONLY VERY LIGHT SNOW OR FLURRIES. CANCELLED THE WINTER
WEATHER ADVISORY A BIT EARLY WITH MINIMAL ADDITIONAL ACCUMULATION
EXPECTED. COLD WIND CHILLS HAVE BEEN OCCURRING OVER THE SOUTHERN
LARAMIE RANGE WITH VALUES IN THE -20 TO -25 RANGE. WITH NOT MUCH
CHANGE IN THE TEMPS OR WINDS THROUGH SUNRISE...SEE NO REASON THAT
WIND CHILLS WILL REACH WARNING CRITERIA(-30)...HOWEVER WILL CONTINUE
TO MONITOR. SOUTHERLY WINDS WILL PERSIST THROUGH THE AFTN ACROSS
THE PLAINS WITH LOW LEVEL UPSLOPE ALONG THE CHEYENNE RIDGE. ALL
MODELS SHOW LOW CLOUDS BEING QUITE PERSISTENT ALONG THE CHEYENNE
RIDGE AND INTO THE SOUTHERN PANHANDLE THROUGH THE EARLY AFTN WHICH
WILL KEEP TEMPS FROM WARMING TOO MUCH COMPARED TO YESTERDAY. OTHER
AREAS WHERE CLEARING OCCURS WILL WARM 5-10 DEGREES...BUT THAT
STILL PUTS US AROUND 20 DEGREES BELOW NORMAL FOR LATE FEB. PRETTY
QUIET WEATHER FROM THIS EVENING THROUGH MIDDAY SATURDAY. WINDS
WILL BE WEAK AND RADIATIONAL COOLING WILL BE BETTER TONIGHT WITH
LESS LOW CLOUDS PRESENT...SO LOWS WILL ONCE AGAIN FALL INTO THE
SINGLE DIGITS.

ANOTHER LIGHT SNOW EVENT APPEARS POSSIBLE FROM MAINLY SAT AFTN
THROUGH SAT NIGHT. THE 00Z EURO HOWEVER CONTINUES TO BE THE OUTLIER
IN SHOWING ALMOST ALL THE QPF TO THE SOUTH OF THE COLORADO BORDER.
THE NAM HAS COME MORE IN LINE WITH THE CONSISTENTLY WETTER GFS...
SHOWING WIDESPREAD 0.1-0.2 INCHES OVER MUCH OF THE CWA. WITH LOW
LEVEL UPSLOPE AND ISENTROPIC LIFT BEING THE PRIMARY FORCING
MECHANISMS... STILL BELIEVE THAT MOST LOCATIONS WILL ONLY PICK UP
A FEW INCHES AND BEING LARGELY SUB-ADVISORY. WITH WINDS LARGELY
REMAINING BELOW 15 KTS...AREAS OF BLOWING SNOW WILL NOT BE A
CONCERN. PRECIP COMES TO AN END BY LATE SUN MORNING WITH ANOTHER
CHILLY DAY IN STORE.

.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 AM MST FRI FEB 27 2015

00Z MEDIUM RANGE MODELS ARE IN GOOD AGREEMENT PORTRAYING A SPLIT
FLOW ALOFT WITH A MORE PROGRESSIVE NORTHERN STREAM AND SLOWER
SOUTHERN STREAM. WEST-SOUTHWEST FLOW ALOFT AHEAD OF CA/NV TROUGH
WILL ADVECT ABUNDANT PACIFIC MOISTURE ACROSS THE FOUR CORNERS AND
CENTRAL ROCKIES EARLY NEXT WEEK. POTENT NORTHERN STREAM SHORTWAVE
MOVING ACROSS THE NORTHERN ROCKIES WILL PROPEL A ARCTIC COLD FRONT
SOUTHEAST ACROSS THE CWA BY TUESDAY MORNING. PRIOR TO THE FROPA...
A SURFACE LOW OVER THE FOUR CORNERS TRACKS NORTHEAST TO EAST
THROUGH SOUTHERN COLORADO AND KANSAS. POST-FRONTAL UPSLOPE NORTHEAST
LOW LEVEL FLOW...Q-G LIFT FROM RIGHT REAR QUAD OF UPPER JET AND
OVERRUNNING MOISTURE ACROSS A SHALLOW COLD AIR MASS WILL SET THE
STAGE FOR WIDESPREAD ACCUMULATING SNOW TUESDAY. GUSTY NORTH-NORTHEAST
WINDS WILL CREATE AREAS OF BLOWING/DRIFTING SNOW. IT`S EARLY TO
FORECAST SNOW AMOUNTS...BUT THIS SYSTEM WILL BE PROGRESSIVE WITH
SNOW TAPERING OFF FROM NORTHWEST TO SOUTHEAST TUESDAY NIGHT AS
COLD HIGH PRESSURE BUILDS ACROSS THE REGION. TEMPERATURES WILL BE
MILDER AHEAD OF THE FRONT MONDAY BUT AT LEAST 1O DEGREES BELOW
NORMAL. MUCH COLDER TEMPERATURES RETURN TUESDAY AND LAST THROUGH
MIDWEEK WITH HIGHS IN THE TEENS AND LOWS FROM 10 BELOW TO 10 ABOVE
ZERO. IN THE WAKE OF THE MIDWEEK SYSTEM...FLOW ALOFT BACKS FROM
NORTH- NORTHWEST TO MORE ZONAL THURSDAY. WESTERLY 700MB WINDS
PICK UP TO 40 KT THURSDAY RESULTING IN GUSTY DOWNSLOPE WINDS LEE
OF THE FRONT RANGE PUSHING THE MERCURY INTO THE 30S.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 230 AM MST FRI FEB 27 2015

LIGHT-MODERATE UPSLOPE SOUTHEASTERLY WINDS WILL RESULT IN
PREVAILING IFR-LIFR CIGS/VSBYS OVER FAR SOUTHEAST WY INCLUDING
KCYS THROUGH MUCH OF THE DAY. MVFR-IFR CIGS/VSBYS WILL AFFECT
PORTIONS OF THE LARAMIE VALLEY AND MUCH OF WESTERN NE PANHANDLE
THIS MORNING BEFORE SLOW IMPROVEMENT TO VFR THIS AFTERNOON.
CONDITIONS WILL DETERIORATE TO MVFR-IFR THIS EVENING AT KCYS...
KAIA...KSNY AND KBFF WITH LIGHT SOUTHERLY WINDS.

&&

.FIRE WEATHER...
ISSUED AT 245 AM MST FRI FEB 27 2015

NO FIRE WEATHER CONCERNS OVER THE NEXT WEEK. TEMPERATURES WILL
CONTINUE TO REMAIN BELOW NORMAL. WIDESPREAD LIGHT SNOW COULD FALL
SATURDAY AFTERNOON THROUGH THE NIGHT...ESPECIALLY FOR AREAS ALONG
THE COLORADO BORDER.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

SHORT TERM...FINCH
LONG TERM...JAMSKI
AVIATION...JAMSKI
FIRE WEATHER...FINCH



000
FXUS65 KRIW 270932
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
232 AM MST FRI FEB 27 2015

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT

A PUSH OF MOISTURE MOVING IN THE NORTHWEST FLOW WILL KEEP SOME LIGHT
SHOWER ACTIVITY ACROSS NORTHWESTERN WYOMING TODAY. THE VERY WEAK
DISTURBANCE USHERING THIS MOISTURE PUSH WILL CONTINUE TO MOVE EAST
THROUGH THE FORECAST AREA OVERNIGHT. THE MOISTURE IS EXPECTED TO
INCREASE AND SPREAD ACROSS THE NORTHERN THIRD OF THE FORECAST AREA
BY SATURDAY MORNING. TEMPERATURES WILL BE ABLE TO WARM
SLIGHTLY...THOUGH WILL STILL REMAIN COOL.

AN AREA OF LOW PRESSURE OVER THE PACIFIC NORTHWEST WILL DIVE SOUTH
ON SATURDAY...ARRIVING OVER CALIFORNIA SATURDAY. AS THIS SYSTEM
MOVES SOUTH IT WILL BRING COOLING TEMPERATURES...AND SEND ADDITIONAL
PULSES OF MOISTURE OVER THE FORECAST AREA. THE BEST OF THESE PULSES
IS NOT EXPECTED TO ARRIVE UNTIL LATE SATURDAY AFTERNOON...AND WILL
PRIMARILY IMPACT SOUTHWESTERN WYOMING. THIS SYSTEM WILL CONTINUE TO
MOVE SOUTH THROUGH SUNDAY WITH PRECIPITATION LINGERING OVER SOUTHERN
WYOMING THROUGH SUNDAY AFTERNOON. A BRIEF PERIOD OF DRY CONDITIONS
POSSIBLE SUNDAY NIGHT...THOUGH MODELS DO INDICATE THE POTENTIAL FOR
ADDITIONAL MOISTURE ACROSS SOUTHERN WYOMING DURING THE LATE EVENING
HOURS OF SUNDAY.

.LONG TERM...MONDAY THROUGH FRIDAY

MAIN CHANGE FOR TONIGHT ARE THE MODELS NOT SHOWING AS MUCH ENERGY
DIGGING INTO THE GREAT BASIN/INTER-MOUNTAIN WEST MONDAY NIGHT AND
TUESDAY AS LAST NIGHT. MORE SHEARING OR JUST OVERALL LESS ENERGY.
THE SYSTEM THE MODELS TRACK FROM KAMCHATKA YESTERDAY IS STILL THE
SAME BUT THE END SOLUTION IS JUST DIFFERENT. STILL LOOKS LIKE SNOW
SPREADING S AND SE ACROSS THE AREA MONDAY NIGHT INTO EARLY TUESDAY
AND TURNING SHARPLY COLDER. SOME FAIRLY DECENT QG FORCING MAY
COMBINE WITH SOME INITIAL RRQ JET DYNAMICS MONDAY NIGHT AND THEN
LEFT EXIT REGION ON TUE WITH THE NEXT JET APPROACHING. WITH LESS
ENERGY TO THE WEST...MOVEMENT IS FASTER AND NOW WE MAY ACTUALLY
CLEAR BY WEDNESDAY MORNING LEADING TO SOME BITTER COLD LOWS. A
COLD COUPLE DAYS THOUGH FOR TUE AND WED. ON THE PLUS SIDE...THE
RIDGE FLATTENS MORE QUICKLY WITH A RATHER FAST MODERATION THURSDAY
INTO FRIDAY ON THE GFS. BACK TRACKING A LITTLE...THE WEEKEND
SYSTEM ENERGY LINGERS JUST TO THE SOUTH TO START THIS PERIOD
MONDAY WITH CONTINUED POTENTIAL FOR CLOUDS AND MAYBE EVEN SOME
VERY LIGHT PCPN IN OUR FAR SRN ZONES. OTHERWISE... DETERIORATING
CONDS BEGINNING LATER MONDAY ONWARD WITH OUR AFOREMENTIONED MONDAY
NIGHT/TUE SYSTEM FAST APPROACHING. RIGHT AT THE END OF THE MEDIUM
RANGE PERIOD...THE MODELS DIVERGE AS TO THE HANDLING OF A PIECE OF
ENERGY CURRENTLY COMING OFF THE ASIA COAST. THE GFS BRINGS IT
FURTHER OVER THE RIDGE AND INTO THE NRN PLAINS WHILE THE EURO
BRINGS THIS SHORTWAVE AT A LITTLE LOWER LATITUDE ALLOWING IT TO
DIG SE INTO OUR AREA NEXT FRIDAY NIGHT. KEEPING IT DRY FOR NOW.
THE GFS WOULD HAVE A MUCH NICER DAY ON FRIDAY WHILE THE ECMWF IS
ALREADY DIGGING THE LOW TOWARDS US WITH FALLING TEMPS BEHIND A
COLD FRONT.

&&

.AVIATION.../12Z ISSUANCE/

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

VFR TO MVFR CONDITIONS WILL OCCUR WITH LINGERING LIGHT SNOW OR
FLURRIES UNTIL 13Z. AFTER 13Z VFR CONDITIONS ARE EXPECTED THROUGH
00Z. CLOUDS WILL LOWER OVER NORTHERN WY AFTER 00Z WITH AREAS OF MVFR
CONDITIONS OCCURRING THROUGH 12Z SATURDAY DUE TO LOW CLOUDS AND
AREAS OF LIGHT SNOW. AFTER 06Z SATURDAY...FROM KLND TO KCPR...AREAS
OF MVFR CONDITIONS WILL OCCUR DUE TO LOW CLOUDS AND AREAS OF LIGHT
SNOW.

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

VFR TO MVFR CONDITIONS IN SOUTHWEST WY WHERE LOWER CLOUDS AND
LINGERING LIGHT SNOW OR FLURRIES WILL OCCUR THROUGH 14Z. LOCAL IFR
CONDITIONS ARE POSSIBLE. CONDITIONS IN SOUTHWEST WY WILL IMPROVE TO
VFR BY 17Z AND VFR CONDITIONS WILL PREVAIL UNTIL 06Z SATURDAY. AFTER
06Z SATURDAY AREAS OF MVFR CONDITIONS WILL DEVELOP ALONG WITH SOME
LIGHT SNOW.

FOR THE KJAC TERMINAL SITE VFR CONDITIONS ARE FORECAST THROUGH 16Z.
THEN MVFR CONDITIONS WILL PREVAIL AROUND 18Z THROUGH 08Z SATURDAY AS
LIGHT SNOW DEVELOPS OVER NORTHWEST WY BY 18Z AND CONTINUES THROUGH
09Z SATURDAY. EXPECT MOUNTAIN OBSCURATION AT TIMES IN NW WY THIS
AFTERNOON AND TONIGHT.

&&

.FIRE WEATHER...

A SOMEWHAT BUSY FORECAST PERIOD ACROSS THE AREA. SHOWER ACTIVITY
WILL REMAIN POSSIBLE OVER THE NORTHERN THIRD OF THE AREA AS A
DISTURBANCES MOVES ACROSS THE AREA IN THE CONTINUED NORTHWEST FLOW.
AFTER A VERY SLIGHT WARMING TODAY...TEMPERATURES WILL AGAIN COOL
SATURDAY AS AN AREA OF LOW PRESSURE MOVES SOUTH ALONG THE PACIFIC
COASTLINE. AS THIS SYSTEM PROGRESSES...IT WILL SPREAD ADDITIONAL
SHOWERS ACROSS SOUTHWESTERN WYOMING...WITH SOUTHERN WYOMING
EXPERIENCING THE BRUNT OF THE SHOWER ACTIVITY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...PS
AVIATION...AR
FIRE WEATHER...BRANHAM











000
FXUS65 KRIW 270932
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
232 AM MST FRI FEB 27 2015

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT

A PUSH OF MOISTURE MOVING IN THE NORTHWEST FLOW WILL KEEP SOME LIGHT
SHOWER ACTIVITY ACROSS NORTHWESTERN WYOMING TODAY. THE VERY WEAK
DISTURBANCE USHERING THIS MOISTURE PUSH WILL CONTINUE TO MOVE EAST
THROUGH THE FORECAST AREA OVERNIGHT. THE MOISTURE IS EXPECTED TO
INCREASE AND SPREAD ACROSS THE NORTHERN THIRD OF THE FORECAST AREA
BY SATURDAY MORNING. TEMPERATURES WILL BE ABLE TO WARM
SLIGHTLY...THOUGH WILL STILL REMAIN COOL.

AN AREA OF LOW PRESSURE OVER THE PACIFIC NORTHWEST WILL DIVE SOUTH
ON SATURDAY...ARRIVING OVER CALIFORNIA SATURDAY. AS THIS SYSTEM
MOVES SOUTH IT WILL BRING COOLING TEMPERATURES...AND SEND ADDITIONAL
PULSES OF MOISTURE OVER THE FORECAST AREA. THE BEST OF THESE PULSES
IS NOT EXPECTED TO ARRIVE UNTIL LATE SATURDAY AFTERNOON...AND WILL
PRIMARILY IMPACT SOUTHWESTERN WYOMING. THIS SYSTEM WILL CONTINUE TO
MOVE SOUTH THROUGH SUNDAY WITH PRECIPITATION LINGERING OVER SOUTHERN
WYOMING THROUGH SUNDAY AFTERNOON. A BRIEF PERIOD OF DRY CONDITIONS
POSSIBLE SUNDAY NIGHT...THOUGH MODELS DO INDICATE THE POTENTIAL FOR
ADDITIONAL MOISTURE ACROSS SOUTHERN WYOMING DURING THE LATE EVENING
HOURS OF SUNDAY.

.LONG TERM...MONDAY THROUGH FRIDAY

MAIN CHANGE FOR TONIGHT ARE THE MODELS NOT SHOWING AS MUCH ENERGY
DIGGING INTO THE GREAT BASIN/INTER-MOUNTAIN WEST MONDAY NIGHT AND
TUESDAY AS LAST NIGHT. MORE SHEARING OR JUST OVERALL LESS ENERGY.
THE SYSTEM THE MODELS TRACK FROM KAMCHATKA YESTERDAY IS STILL THE
SAME BUT THE END SOLUTION IS JUST DIFFERENT. STILL LOOKS LIKE SNOW
SPREADING S AND SE ACROSS THE AREA MONDAY NIGHT INTO EARLY TUESDAY
AND TURNING SHARPLY COLDER. SOME FAIRLY DECENT QG FORCING MAY
COMBINE WITH SOME INITIAL RRQ JET DYNAMICS MONDAY NIGHT AND THEN
LEFT EXIT REGION ON TUE WITH THE NEXT JET APPROACHING. WITH LESS
ENERGY TO THE WEST...MOVEMENT IS FASTER AND NOW WE MAY ACTUALLY
CLEAR BY WEDNESDAY MORNING LEADING TO SOME BITTER COLD LOWS. A
COLD COUPLE DAYS THOUGH FOR TUE AND WED. ON THE PLUS SIDE...THE
RIDGE FLATTENS MORE QUICKLY WITH A RATHER FAST MODERATION THURSDAY
INTO FRIDAY ON THE GFS. BACK TRACKING A LITTLE...THE WEEKEND
SYSTEM ENERGY LINGERS JUST TO THE SOUTH TO START THIS PERIOD
MONDAY WITH CONTINUED POTENTIAL FOR CLOUDS AND MAYBE EVEN SOME
VERY LIGHT PCPN IN OUR FAR SRN ZONES. OTHERWISE... DETERIORATING
CONDS BEGINNING LATER MONDAY ONWARD WITH OUR AFOREMENTIONED MONDAY
NIGHT/TUE SYSTEM FAST APPROACHING. RIGHT AT THE END OF THE MEDIUM
RANGE PERIOD...THE MODELS DIVERGE AS TO THE HANDLING OF A PIECE OF
ENERGY CURRENTLY COMING OFF THE ASIA COAST. THE GFS BRINGS IT
FURTHER OVER THE RIDGE AND INTO THE NRN PLAINS WHILE THE EURO
BRINGS THIS SHORTWAVE AT A LITTLE LOWER LATITUDE ALLOWING IT TO
DIG SE INTO OUR AREA NEXT FRIDAY NIGHT. KEEPING IT DRY FOR NOW.
THE GFS WOULD HAVE A MUCH NICER DAY ON FRIDAY WHILE THE ECMWF IS
ALREADY DIGGING THE LOW TOWARDS US WITH FALLING TEMPS BEHIND A
COLD FRONT.

&&

.AVIATION.../12Z ISSUANCE/

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

VFR TO MVFR CONDITIONS WILL OCCUR WITH LINGERING LIGHT SNOW OR
FLURRIES UNTIL 13Z. AFTER 13Z VFR CONDITIONS ARE EXPECTED THROUGH
00Z. CLOUDS WILL LOWER OVER NORTHERN WY AFTER 00Z WITH AREAS OF MVFR
CONDITIONS OCCURRING THROUGH 12Z SATURDAY DUE TO LOW CLOUDS AND
AREAS OF LIGHT SNOW. AFTER 06Z SATURDAY...FROM KLND TO KCPR...AREAS
OF MVFR CONDITIONS WILL OCCUR DUE TO LOW CLOUDS AND AREAS OF LIGHT
SNOW.

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

VFR TO MVFR CONDITIONS IN SOUTHWEST WY WHERE LOWER CLOUDS AND
LINGERING LIGHT SNOW OR FLURRIES WILL OCCUR THROUGH 14Z. LOCAL IFR
CONDITIONS ARE POSSIBLE. CONDITIONS IN SOUTHWEST WY WILL IMPROVE TO
VFR BY 17Z AND VFR CONDITIONS WILL PREVAIL UNTIL 06Z SATURDAY. AFTER
06Z SATURDAY AREAS OF MVFR CONDITIONS WILL DEVELOP ALONG WITH SOME
LIGHT SNOW.

FOR THE KJAC TERMINAL SITE VFR CONDITIONS ARE FORECAST THROUGH 16Z.
THEN MVFR CONDITIONS WILL PREVAIL AROUND 18Z THROUGH 08Z SATURDAY AS
LIGHT SNOW DEVELOPS OVER NORTHWEST WY BY 18Z AND CONTINUES THROUGH
09Z SATURDAY. EXPECT MOUNTAIN OBSCURATION AT TIMES IN NW WY THIS
AFTERNOON AND TONIGHT.

&&

.FIRE WEATHER...

A SOMEWHAT BUSY FORECAST PERIOD ACROSS THE AREA. SHOWER ACTIVITY
WILL REMAIN POSSIBLE OVER THE NORTHERN THIRD OF THE AREA AS A
DISTURBANCES MOVES ACROSS THE AREA IN THE CONTINUED NORTHWEST FLOW.
AFTER A VERY SLIGHT WARMING TODAY...TEMPERATURES WILL AGAIN COOL
SATURDAY AS AN AREA OF LOW PRESSURE MOVES SOUTH ALONG THE PACIFIC
COASTLINE. AS THIS SYSTEM PROGRESSES...IT WILL SPREAD ADDITIONAL
SHOWERS ACROSS SOUTHWESTERN WYOMING...WITH SOUTHERN WYOMING
EXPERIENCING THE BRUNT OF THE SHOWER ACTIVITY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...BRANHAM
LONG TERM...PS
AVIATION...AR
FIRE WEATHER...BRANHAM










000
FXUS65 KCYS 270504
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1004 PM MST THU FEB 26 2015

.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 318 PM MST THU FEB 26 2015

ONGOING UPSLOPE SNOW EVENT IS THE MAIN CONCERN INITIALLY.
VISIBILITIES HAVE BEEN THE LOWEST AND SNOWFALL RATES THE HIGHEST
AT CHEYENNE REALLY ALL DAY LONG. THIS AS LLVL EASTERLY UPSLOPE
FLOW INTERACTS WITH THE FAVORABLE LEADING EDGE OF SHORTWAVE ENERGY
DIVING SOUTHEAST INTO THE HIGH PLAINS/FRONT RANGE. 12/18Z MODELS
SHOW LLVL LIFT INCREASING ACROSS LARAMIE COUNTY THRU THE REST OF
THE EVENING HOURS. MODELS HAVE CONTINUED TO TREND SNOWFALL AMOUNTS
UP ACROSS CENTRAL/SOUTHERN LARAMIE COUNTY ESPECIALLY FOR THIS
EVENING. SO IN AN EARLIER UPDATE...OPTED TO ISSUE A WINTER WEATHER
ADVISORY FOR CENTRAL LARAMIE COUNTY INCLUDING WRN FOOTHILLS
LOCATIONS EFFECTIVE THRU 10Z FRIDAY. EXPECT GENERALLY 2 TO 4
INCHES TO FALL...WITH THE HIGHEST AMOUNTS IN AREAS NEAREST THE
CHEYENNE RIDGE. LIFT/SNOW WILL DIMINISH SIGNIFICANTLY WITH THE
PASSAGE OF THE MID-LEVEL/H5 TROUGH FRIDAY 09-12Z. AMOUNTS WILL BE
SIGNIFICANTLY LIGHTER OUTSIDE OF LARAMIE COUNTY WITH THIS
SYSTEM...WITH PERHAPS AN INCH OR SO AT LARAMIE... WHEATLAND AND
KIMBALL. RAWLINS AND LOCATIONS TO THE NORTH OF THE NORTH PLATTE
RIVER VALLEY WILL SEE NOTHING AT ALL OR JUST SOME FLURRIES.
FORTUNATELY WINDS ARE ONLY PROGD TO BE AROUND 10 KNOTS...SO DONT
EXPECT BLOWING SNOW TO BE A CONCERN. ANOTHER COLD NIGHT AHEAD WITH
LOWS FALLING INTO THE SINGLE DIGITS OR SINGLE DIGITS BELOW ZERO.

QUICK SHORTWAVE RIDGE AXIS WILL USHER IN A MOSTLY DRY DAY FOR
FRIDAY WITH PERHAPS A FEW DEGREES OF WARMING BENEATH A VERY BRIEF
LLVL THERMAL RIDGING. EVEN SO HIGHS ON FRIDAY WILL ONLY REACH THE
TEENS AND 20S.

THE NEXT COLD FRONT WILL SLIDE FROM NORTH TO SOUTH DURING THE DAY
ON SATURDAY AS THE PATTERN FLATTENS AHEAD OF THE FORMING CUT-OFF
OVR THE GREAT BASIN. MOISTURE WILL BE LIMITED INITIALLY ON
SATURDAY AWAITING THE ARRIVAL OF AN EJECTING SHORTWAVE ENERGY AND
RESULTANT FAVORABLE ISENTROPIC LIFT/OVERRUNNING SET-UP. SNOW WILL
OVERSPREAD MUCH OF THE SOUTHERN TIER OF COUNTIES LATE SATURDAY AND
ESPECIALLY SATURDAY NIGHT. ALTHOUGH EXPECT THE BULK OF THE BEST
LIFT TO REMAIN SOUTH OVER COLORADO...SHOULD SEE SOME AT LEAST
LIGHT ACCUMULATIONS ESPECIALLY ALONG THE I80 CORRIDOR.

.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 318 PM MST THU FEB 26 2015

A RATHER COLD PATTERN EXPECTED TO PERSIST OVER THE REGION FOR MOST
OF THIS PERIOD WITH MONDAY LIKELY BEING THE MILDEST DAY THIS
PERIOD. INITIALLY THE CWA WILL BE UNDER CONFLUENT UPPER FLOW
BETWEEN ONE STREAM EMANATING FROM WESTERN CANADA INTO THE
NORTHERN PLAINS AND THE OTHER FROM THE SOUTHWEST CONUS AHEAD OF AN
UPPER LOW OFF THE CAL COAST. STILL CHILLY ACROSS THE AREA SUNDAY
AS A COLD SFC HIGH OVER THE HIGH PLAINS SHIFTS EAST DURING THE
DAY. A SHORTWAVE WILL MOVE INTO THE PACIFIC NW ON MONDAY AND PHASE
WITH THE CALIFORNIA UPPER LOW CREATING A LARGER SCALE UPPER TROF
OVER THE WESTERN CONUS MONDAY NIGHT. AT THE SAME TIME LEE TROFFING
WILL DEVELOP OVER THE HIGH PLAINS WHICH WILL SCOUR OUT THE COLDER
AIR AND BRING A SHORT PERIOD OF WARMING TO THE CWA FOR MONDAY.
MOISTURE FROM THE SOUTHWEST SHOULD GET CAUGHT UP IN THE SWLY FLOW
AHEAD OF THE UPPER TROF AND ADVECT OVER THE CWA MONDAY NIGHT AND
TUESDAY. THE NEXT SURGE OF COLD AIR WILL THEN DROP SOUTH OVER THE
HIGH PLAINS EARLY TUESDAY AND WILL AID IN THE DEVELOPMENT OF SNOW
OVER THE REGION TUESDAY INTO TUESDAY NIGHT. QUITE COLD AGAIN WEDS
WITH SNOW ENDING EARLY AS THE SURFACE HIGH SETTLES ACROSS WY AND
THE MAIN UPPER TROF AXIS PASSES ACROSS LEAVING A NW FLOW ALOFT
OVER THE REGION. MAINLY DRY THURSDAY WITH WARMER TEMPS AGAIN AS
DOWNSLOPE FLOW RETURNS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1001 PM MST THU FEB 26 2015

PROBLEM AREAS LOOK TO BE KCYS AND OUR SOUTHERN NEBRASKA AIRPORTS
OVER THE NEXT 12 HOURS OR SO WITH SOUTHEAST UPSLOPING WIND. WORST
AREA WILL BE KCYS WHICH IS CURRENTLY IFR IN SNOW. SNOW EXPECTED TO
CONTINUE ANOTHER COUPLE HOURS...THEN AFTER IT STOPS...DO BELIEVE
LOWERING CEILINGS WILL MOVE IN. COULD PERSIST MOST OF THE DAY
FRIDAY WITH SOUTH TO SOUTHEAST UPSLOPE WINDS CONTINUING. PRETTY
FAVORABLE WINDS FOR UPSLOPE AT KBFF...KAIA AND POSSIBLY KSNY AS
WELL.

&&

.FIRE WEATHER...
ISSUED AT 318 PM MST THU FEB 26 2015

COLD TEMPERATURES AND UNSETTLED CONDITIONS WILL SUPPRESS ANY FIRE
WEATHER CONCERNS FOR THE FORESEEABLE FUTURE.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 3 AM MST FRIDAY FOR WYZ117-118.

NE...NONE.
&&

$$

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




000
FXUS65 KCYS 270504
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1004 PM MST THU FEB 26 2015

.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 318 PM MST THU FEB 26 2015

ONGOING UPSLOPE SNOW EVENT IS THE MAIN CONCERN INITIALLY.
VISIBILITIES HAVE BEEN THE LOWEST AND SNOWFALL RATES THE HIGHEST
AT CHEYENNE REALLY ALL DAY LONG. THIS AS LLVL EASTERLY UPSLOPE
FLOW INTERACTS WITH THE FAVORABLE LEADING EDGE OF SHORTWAVE ENERGY
DIVING SOUTHEAST INTO THE HIGH PLAINS/FRONT RANGE. 12/18Z MODELS
SHOW LLVL LIFT INCREASING ACROSS LARAMIE COUNTY THRU THE REST OF
THE EVENING HOURS. MODELS HAVE CONTINUED TO TREND SNOWFALL AMOUNTS
UP ACROSS CENTRAL/SOUTHERN LARAMIE COUNTY ESPECIALLY FOR THIS
EVENING. SO IN AN EARLIER UPDATE...OPTED TO ISSUE A WINTER WEATHER
ADVISORY FOR CENTRAL LARAMIE COUNTY INCLUDING WRN FOOTHILLS
LOCATIONS EFFECTIVE THRU 10Z FRIDAY. EXPECT GENERALLY 2 TO 4
INCHES TO FALL...WITH THE HIGHEST AMOUNTS IN AREAS NEAREST THE
CHEYENNE RIDGE. LIFT/SNOW WILL DIMINISH SIGNIFICANTLY WITH THE
PASSAGE OF THE MID-LEVEL/H5 TROUGH FRIDAY 09-12Z. AMOUNTS WILL BE
SIGNIFICANTLY LIGHTER OUTSIDE OF LARAMIE COUNTY WITH THIS
SYSTEM...WITH PERHAPS AN INCH OR SO AT LARAMIE... WHEATLAND AND
KIMBALL. RAWLINS AND LOCATIONS TO THE NORTH OF THE NORTH PLATTE
RIVER VALLEY WILL SEE NOTHING AT ALL OR JUST SOME FLURRIES.
FORTUNATELY WINDS ARE ONLY PROGD TO BE AROUND 10 KNOTS...SO DONT
EXPECT BLOWING SNOW TO BE A CONCERN. ANOTHER COLD NIGHT AHEAD WITH
LOWS FALLING INTO THE SINGLE DIGITS OR SINGLE DIGITS BELOW ZERO.

QUICK SHORTWAVE RIDGE AXIS WILL USHER IN A MOSTLY DRY DAY FOR
FRIDAY WITH PERHAPS A FEW DEGREES OF WARMING BENEATH A VERY BRIEF
LLVL THERMAL RIDGING. EVEN SO HIGHS ON FRIDAY WILL ONLY REACH THE
TEENS AND 20S.

THE NEXT COLD FRONT WILL SLIDE FROM NORTH TO SOUTH DURING THE DAY
ON SATURDAY AS THE PATTERN FLATTENS AHEAD OF THE FORMING CUT-OFF
OVR THE GREAT BASIN. MOISTURE WILL BE LIMITED INITIALLY ON
SATURDAY AWAITING THE ARRIVAL OF AN EJECTING SHORTWAVE ENERGY AND
RESULTANT FAVORABLE ISENTROPIC LIFT/OVERRUNNING SET-UP. SNOW WILL
OVERSPREAD MUCH OF THE SOUTHERN TIER OF COUNTIES LATE SATURDAY AND
ESPECIALLY SATURDAY NIGHT. ALTHOUGH EXPECT THE BULK OF THE BEST
LIFT TO REMAIN SOUTH OVER COLORADO...SHOULD SEE SOME AT LEAST
LIGHT ACCUMULATIONS ESPECIALLY ALONG THE I80 CORRIDOR.

.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 318 PM MST THU FEB 26 2015

A RATHER COLD PATTERN EXPECTED TO PERSIST OVER THE REGION FOR MOST
OF THIS PERIOD WITH MONDAY LIKELY BEING THE MILDEST DAY THIS
PERIOD. INITIALLY THE CWA WILL BE UNDER CONFLUENT UPPER FLOW
BETWEEN ONE STREAM EMANATING FROM WESTERN CANADA INTO THE
NORTHERN PLAINS AND THE OTHER FROM THE SOUTHWEST CONUS AHEAD OF AN
UPPER LOW OFF THE CAL COAST. STILL CHILLY ACROSS THE AREA SUNDAY
AS A COLD SFC HIGH OVER THE HIGH PLAINS SHIFTS EAST DURING THE
DAY. A SHORTWAVE WILL MOVE INTO THE PACIFIC NW ON MONDAY AND PHASE
WITH THE CALIFORNIA UPPER LOW CREATING A LARGER SCALE UPPER TROF
OVER THE WESTERN CONUS MONDAY NIGHT. AT THE SAME TIME LEE TROFFING
WILL DEVELOP OVER THE HIGH PLAINS WHICH WILL SCOUR OUT THE COLDER
AIR AND BRING A SHORT PERIOD OF WARMING TO THE CWA FOR MONDAY.
MOISTURE FROM THE SOUTHWEST SHOULD GET CAUGHT UP IN THE SWLY FLOW
AHEAD OF THE UPPER TROF AND ADVECT OVER THE CWA MONDAY NIGHT AND
TUESDAY. THE NEXT SURGE OF COLD AIR WILL THEN DROP SOUTH OVER THE
HIGH PLAINS EARLY TUESDAY AND WILL AID IN THE DEVELOPMENT OF SNOW
OVER THE REGION TUESDAY INTO TUESDAY NIGHT. QUITE COLD AGAIN WEDS
WITH SNOW ENDING EARLY AS THE SURFACE HIGH SETTLES ACROSS WY AND
THE MAIN UPPER TROF AXIS PASSES ACROSS LEAVING A NW FLOW ALOFT
OVER THE REGION. MAINLY DRY THURSDAY WITH WARMER TEMPS AGAIN AS
DOWNSLOPE FLOW RETURNS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1001 PM MST THU FEB 26 2015

PROBLEM AREAS LOOK TO BE KCYS AND OUR SOUTHERN NEBRASKA AIRPORTS
OVER THE NEXT 12 HOURS OR SO WITH SOUTHEAST UPSLOPING WIND. WORST
AREA WILL BE KCYS WHICH IS CURRENTLY IFR IN SNOW. SNOW EXPECTED TO
CONTINUE ANOTHER COUPLE HOURS...THEN AFTER IT STOPS...DO BELIEVE
LOWERING CEILINGS WILL MOVE IN. COULD PERSIST MOST OF THE DAY
FRIDAY WITH SOUTH TO SOUTHEAST UPSLOPE WINDS CONTINUING. PRETTY
FAVORABLE WINDS FOR UPSLOPE AT KBFF...KAIA AND POSSIBLY KSNY AS
WELL.

&&

.FIRE WEATHER...
ISSUED AT 318 PM MST THU FEB 26 2015

COLD TEMPERATURES AND UNSETTLED CONDITIONS WILL SUPPRESS ANY FIRE
WEATHER CONCERNS FOR THE FORESEEABLE FUTURE.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 3 AM MST FRIDAY FOR WYZ117-118.

NE...NONE.
&&

$$

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



000
FXUS65 KRIW 270501
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1001 PM MST THU FEB 26 2015

.SHORT TERM...TONIGHT THROUGH FRIDAY (ISSUED AT 225 PM MDT)

SURFACE HIGH BUILDS INTO CENTRAL HIGH PLAINS TONIGHT. CHALLENGE
FOR CENTRAL WYOMING WILL BE TIMING OF DECREASING CLOUD COVER. WEAK
LOW LEVEL UPSLOPE FLOW PERSISTS...BUT SURFACE FLOW TO TURN MORE
SOUTHERLY TONIGHT. BEST CONFIDENCE FOR CLEARING WILL BE OVER
NATRONA AND JOHNSON COUNTIES...TO NORTHERN SECTIONS OF FORECAST
AREA. REGARDLESS...IT WILL BE QUITE COLD TONIGHT INTO EARLY FRIDAY.

WEAK FLOW ALOFT SETS UP ON FRIDAY WITH UPPER LEVEL LOW DROPPING INTO
CALIFORNIA. AS A RESULT...LITTLE OR NO ENERGY OVER WYOMING WELL AHEAD
OF THIS TROUGH. COULD STILL SEE A FEW MOUNTAIN SNOW SHOWERS WITH
HEATING OF THE DAY. OTHERWISE...ANOTHER COLD DAY ACROSS WEST
CENTRAL WYOMING WITH MORE SUNSHINE EXPECTED. WITH A VERY LIGHT
SURFACE WIND...IT SHOULD FEEL DECENT OUTDOORS ON FRIDAY.

.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY

AT THIS TIME...FRIDAY NIGHT LOOKS LIKE A MAINLY QUIET PERIOD WITH
JUST A FEW OROGRAPHIC SNOW SHOWERS ACROSS THE WESTERN MOUNTAINS. THE
REST OF THE REGION LOOKS MAINLY DRY WITH BELOW NORMAL TEMPERATURES
FOR THE START OF THE WEEKEND.

THE FIRST OF TWO SYSTEMS OF CONCERN IN THE LONG RANGE WILL START TO
EFFECT THE WEATHER FOR SATURDAY. A PIECE OF ENERGY WILL MOVE OFF A
CUT OFF LOW OVER CALIFORNIA AND MOVE INTO THE ROCKIES. HOWEVER...IT
APPEARS THAT THE BEST UPPER LEVEL SUPPORT WILL REMAIN OVER UTAH AND
COLORADO. AT AS RESULT...RIGHT NOW THIS LOOKS TO MAINLY A NUISANCE
EVENT AND ONLY EFFECT SOUTHERN PORTIONS OF THE COUNTY WARNING AREA
AND MAINLY WEST OF THE DIVIDE. BOTH THE GFS...EUROPEAN AND NAM ARE
IN GOOD AGREEMENT OF THIS. AS A RESULT...WE TRIMMED POPS ACROSS
AREAS NORTH AND EAST OF THE WIND RIVER RANGE FOR SATURDAY AND
SATURDAY NIGHT. EVEN IN AREAS THAT GET SNOW...THIS DOES NOT LOOK
WORTHY OF ANY SORT OF WARNINGS OR ADVISORIES RIGHT NOW. ON
SUNDAY...THERE IS SOME SLIGHT DISAGREEMENT WITH THE GFS KEEPING A
FEW SHOWERS ALONG THE SOUTHERN BORDER AND THE EUROPEAN MAINLY DRY.
WITH THE DIFFERENCES WE MADE FEW CHANGES TO CONTINUITY. MAINLY DRY
BUT CONTINUED CHILLY WEATHER WILL BE THE RULE FOR MONDAY WITH WEAK
SURFACE HIGH PRESSURE IN CONTROL.

THE NEXT AND PROBABLY MORE IMPACTFUL SYSTEM THEN APPROACHES FOR
MONDAY NIGHT AND ESPECIALLY FOR TUESDAY. THIS ONE HAS CHILLY ORIGINS
COMING IN FROM ALASKA.  THE MODELS AGAIN ARE IN FAIRLY GOOD
AGREEMENT WITH SNOW BEGINNING IN THE WEST ON MONDAY NIGHT AND THEN
SPREADING ACROSS ALL AREAS FOR TUESDAY. THE PREVIOUS FORECAST HAD
CHANCE POPS ACROSS MOST AREAS AND THESE LOOK PRETTY GOOD AT THIS
POINT SO FEW CHANGES WERE MADE. SNOWFALL AMOUNTS ARE STILL UNCERTAIN
RIGHT NOW...AS A LOT WILL DEPEND ON THE JET DYNAMICS AND OF COURSE
THE MODELS ARE PERFECT WITH THIS FIVE DAYS OUT...NOTE SARCASM. THERE
IS ALSO MORE AGREEMENT WITH THE END TIME. THE EUROPEAN HAS COME
AROUND TO THE MORE PROGRESSIVE GFS SOLUTION IN KICKING THE SYSTEM TO
THE SOUTH AND EAST DURING WEDNESDAY WITH ALL AREAS DRY AT THAT
POINT. TUESDAY NIGHT AND WEDNESDAY HAVE THE POTENTIAL TO QUITE COLD.
LOWS TUESDAY NIGHT MAY DEPEND ON HOW QUICKLY THE SKY CLEARS THOUGH.
MAINLY DRY BUT COOL WEATHER WILL BE THE RULE FOR WEDNESDAY INTO
THURSDAY WITH DRY NORTHWEST FLOW PREDOMINATING.

&&

.AVIATION.../06Z ISSUANCE/

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

VFR TO MVFR CONDITIONS WILL OCCUR OVERNIGHT WITH LINGERING LIGHT
SNOW OR FLURRIES UNTIL 12Z. AFTER 12Z VFR CONDITIONS ARE EXPECTED
THROUGH 00Z SATURDAY. CLOUDS WILL LOWER OVER NORTHERN WY AFTER 00Z
SATURDAY WITH AREAS OF MVFR CONDITIONS OCCURRING THROUGH 06Z
SATURDAY.

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

VFR TO MVFR CONDITIONS WILL OCCUR OVERNIGHT IN SOUTHWEST WY WHERE
LOWER CLOUDS AND LINGERING LIGHT SNOW OR FLURRIES WILL OCCUR THROUGH
12Z. LOCAL IFR CONDITIONS ARE POSSIBLE. CONDITIONS IN SOUTHWEST WY
WILL IMPROVE TO VFR BY 16Z AND VFR CONDITIONS WILL PREVAIL UNTIL 06Z
SATURDAY.

FOR THE KJAC TERMINAL SITE VFR CONDITIONS ARE FORECAST THROUGH 16Z.
THEN MVFR CONDITIONS WILL PREVAIL AROUND 18Z THROUGH 06Z SATURDAY AS
LIGHT SNOW DEVELOPS OVER NORTHWEST WY BY 18Z AND CONTINUES THROUGH
06Z SATURDAY. EXPECT MOUNTAIN OBSCURATION AT TIMES IN NW WY.

&&

.FIRE WEATHER...

NO FIRE WEATHER CONCERNS IN THE SHORT TERM...AS A COLD WEATHER
PATTERN CONTINUES FOR THE ENTIRE DISTRICT. LITTLE OR NO
PRECIPITATION THROUGH THE UPCOMING WEEKEND EAST OF THE DIVIDE...
BUT RELATIVE HUMIDITIES TO REMAIN HIGH.

WEST OF THE DIVIDE...INCREASING CLOUDS CAN BE EXPECTED ON FRIDAY.
A WEAK UPPER LEVEL TROUGH WILL MOVE OVER THE WESTERN MOUNTAINS LATE
FRIDAY TO HELP INITIATE SNOW SHOWERS. AREAS OF LIGHT SNOW WILL
PERSIST FRIDAY NIGHT...POSSIBLY REACHING THE WESTERN VALLEYS OF
WYOMING.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...KPL
LONG TERM...HATTINGS
AVIATION...AR
FIRE WEATHER...KPL







000
FXUS65 KRIW 270501
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1001 PM MST THU FEB 26 2015

.SHORT TERM...TONIGHT THROUGH FRIDAY (ISSUED AT 225 PM MDT)

SURFACE HIGH BUILDS INTO CENTRAL HIGH PLAINS TONIGHT. CHALLENGE
FOR CENTRAL WYOMING WILL BE TIMING OF DECREASING CLOUD COVER. WEAK
LOW LEVEL UPSLOPE FLOW PERSISTS...BUT SURFACE FLOW TO TURN MORE
SOUTHERLY TONIGHT. BEST CONFIDENCE FOR CLEARING WILL BE OVER
NATRONA AND JOHNSON COUNTIES...TO NORTHERN SECTIONS OF FORECAST
AREA. REGARDLESS...IT WILL BE QUITE COLD TONIGHT INTO EARLY FRIDAY.

WEAK FLOW ALOFT SETS UP ON FRIDAY WITH UPPER LEVEL LOW DROPPING INTO
CALIFORNIA. AS A RESULT...LITTLE OR NO ENERGY OVER WYOMING WELL AHEAD
OF THIS TROUGH. COULD STILL SEE A FEW MOUNTAIN SNOW SHOWERS WITH
HEATING OF THE DAY. OTHERWISE...ANOTHER COLD DAY ACROSS WEST
CENTRAL WYOMING WITH MORE SUNSHINE EXPECTED. WITH A VERY LIGHT
SURFACE WIND...IT SHOULD FEEL DECENT OUTDOORS ON FRIDAY.

.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY

AT THIS TIME...FRIDAY NIGHT LOOKS LIKE A MAINLY QUIET PERIOD WITH
JUST A FEW OROGRAPHIC SNOW SHOWERS ACROSS THE WESTERN MOUNTAINS. THE
REST OF THE REGION LOOKS MAINLY DRY WITH BELOW NORMAL TEMPERATURES
FOR THE START OF THE WEEKEND.

THE FIRST OF TWO SYSTEMS OF CONCERN IN THE LONG RANGE WILL START TO
EFFECT THE WEATHER FOR SATURDAY. A PIECE OF ENERGY WILL MOVE OFF A
CUT OFF LOW OVER CALIFORNIA AND MOVE INTO THE ROCKIES. HOWEVER...IT
APPEARS THAT THE BEST UPPER LEVEL SUPPORT WILL REMAIN OVER UTAH AND
COLORADO. AT AS RESULT...RIGHT NOW THIS LOOKS TO MAINLY A NUISANCE
EVENT AND ONLY EFFECT SOUTHERN PORTIONS OF THE COUNTY WARNING AREA
AND MAINLY WEST OF THE DIVIDE. BOTH THE GFS...EUROPEAN AND NAM ARE
IN GOOD AGREEMENT OF THIS. AS A RESULT...WE TRIMMED POPS ACROSS
AREAS NORTH AND EAST OF THE WIND RIVER RANGE FOR SATURDAY AND
SATURDAY NIGHT. EVEN IN AREAS THAT GET SNOW...THIS DOES NOT LOOK
WORTHY OF ANY SORT OF WARNINGS OR ADVISORIES RIGHT NOW. ON
SUNDAY...THERE IS SOME SLIGHT DISAGREEMENT WITH THE GFS KEEPING A
FEW SHOWERS ALONG THE SOUTHERN BORDER AND THE EUROPEAN MAINLY DRY.
WITH THE DIFFERENCES WE MADE FEW CHANGES TO CONTINUITY. MAINLY DRY
BUT CONTINUED CHILLY WEATHER WILL BE THE RULE FOR MONDAY WITH WEAK
SURFACE HIGH PRESSURE IN CONTROL.

THE NEXT AND PROBABLY MORE IMPACTFUL SYSTEM THEN APPROACHES FOR
MONDAY NIGHT AND ESPECIALLY FOR TUESDAY. THIS ONE HAS CHILLY ORIGINS
COMING IN FROM ALASKA.  THE MODELS AGAIN ARE IN FAIRLY GOOD
AGREEMENT WITH SNOW BEGINNING IN THE WEST ON MONDAY NIGHT AND THEN
SPREADING ACROSS ALL AREAS FOR TUESDAY. THE PREVIOUS FORECAST HAD
CHANCE POPS ACROSS MOST AREAS AND THESE LOOK PRETTY GOOD AT THIS
POINT SO FEW CHANGES WERE MADE. SNOWFALL AMOUNTS ARE STILL UNCERTAIN
RIGHT NOW...AS A LOT WILL DEPEND ON THE JET DYNAMICS AND OF COURSE
THE MODELS ARE PERFECT WITH THIS FIVE DAYS OUT...NOTE SARCASM. THERE
IS ALSO MORE AGREEMENT WITH THE END TIME. THE EUROPEAN HAS COME
AROUND TO THE MORE PROGRESSIVE GFS SOLUTION IN KICKING THE SYSTEM TO
THE SOUTH AND EAST DURING WEDNESDAY WITH ALL AREAS DRY AT THAT
POINT. TUESDAY NIGHT AND WEDNESDAY HAVE THE POTENTIAL TO QUITE COLD.
LOWS TUESDAY NIGHT MAY DEPEND ON HOW QUICKLY THE SKY CLEARS THOUGH.
MAINLY DRY BUT COOL WEATHER WILL BE THE RULE FOR WEDNESDAY INTO
THURSDAY WITH DRY NORTHWEST FLOW PREDOMINATING.

&&

.AVIATION.../06Z ISSUANCE/

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

VFR TO MVFR CONDITIONS WILL OCCUR OVERNIGHT WITH LINGERING LIGHT
SNOW OR FLURRIES UNTIL 12Z. AFTER 12Z VFR CONDITIONS ARE EXPECTED
THROUGH 00Z SATURDAY. CLOUDS WILL LOWER OVER NORTHERN WY AFTER 00Z
SATURDAY WITH AREAS OF MVFR CONDITIONS OCCURRING THROUGH 06Z
SATURDAY.

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

VFR TO MVFR CONDITIONS WILL OCCUR OVERNIGHT IN SOUTHWEST WY WHERE
LOWER CLOUDS AND LINGERING LIGHT SNOW OR FLURRIES WILL OCCUR THROUGH
12Z. LOCAL IFR CONDITIONS ARE POSSIBLE. CONDITIONS IN SOUTHWEST WY
WILL IMPROVE TO VFR BY 16Z AND VFR CONDITIONS WILL PREVAIL UNTIL 06Z
SATURDAY.

FOR THE KJAC TERMINAL SITE VFR CONDITIONS ARE FORECAST THROUGH 16Z.
THEN MVFR CONDITIONS WILL PREVAIL AROUND 18Z THROUGH 06Z SATURDAY AS
LIGHT SNOW DEVELOPS OVER NORTHWEST WY BY 18Z AND CONTINUES THROUGH
06Z SATURDAY. EXPECT MOUNTAIN OBSCURATION AT TIMES IN NW WY.

&&

.FIRE WEATHER...

NO FIRE WEATHER CONCERNS IN THE SHORT TERM...AS A COLD WEATHER
PATTERN CONTINUES FOR THE ENTIRE DISTRICT. LITTLE OR NO
PRECIPITATION THROUGH THE UPCOMING WEEKEND EAST OF THE DIVIDE...
BUT RELATIVE HUMIDITIES TO REMAIN HIGH.

WEST OF THE DIVIDE...INCREASING CLOUDS CAN BE EXPECTED ON FRIDAY.
A WEAK UPPER LEVEL TROUGH WILL MOVE OVER THE WESTERN MOUNTAINS LATE
FRIDAY TO HELP INITIATE SNOW SHOWERS. AREAS OF LIGHT SNOW WILL
PERSIST FRIDAY NIGHT...POSSIBLY REACHING THE WESTERN VALLEYS OF
WYOMING.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...KPL
LONG TERM...HATTINGS
AVIATION...AR
FIRE WEATHER...KPL








000
FXUS65 KRIW 270501
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1001 PM MST THU FEB 26 2015

.SHORT TERM...TONIGHT THROUGH FRIDAY (ISSUED AT 225 PM MDT)

SURFACE HIGH BUILDS INTO CENTRAL HIGH PLAINS TONIGHT. CHALLENGE
FOR CENTRAL WYOMING WILL BE TIMING OF DECREASING CLOUD COVER. WEAK
LOW LEVEL UPSLOPE FLOW PERSISTS...BUT SURFACE FLOW TO TURN MORE
SOUTHERLY TONIGHT. BEST CONFIDENCE FOR CLEARING WILL BE OVER
NATRONA AND JOHNSON COUNTIES...TO NORTHERN SECTIONS OF FORECAST
AREA. REGARDLESS...IT WILL BE QUITE COLD TONIGHT INTO EARLY FRIDAY.

WEAK FLOW ALOFT SETS UP ON FRIDAY WITH UPPER LEVEL LOW DROPPING INTO
CALIFORNIA. AS A RESULT...LITTLE OR NO ENERGY OVER WYOMING WELL AHEAD
OF THIS TROUGH. COULD STILL SEE A FEW MOUNTAIN SNOW SHOWERS WITH
HEATING OF THE DAY. OTHERWISE...ANOTHER COLD DAY ACROSS WEST
CENTRAL WYOMING WITH MORE SUNSHINE EXPECTED. WITH A VERY LIGHT
SURFACE WIND...IT SHOULD FEEL DECENT OUTDOORS ON FRIDAY.

.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY

AT THIS TIME...FRIDAY NIGHT LOOKS LIKE A MAINLY QUIET PERIOD WITH
JUST A FEW OROGRAPHIC SNOW SHOWERS ACROSS THE WESTERN MOUNTAINS. THE
REST OF THE REGION LOOKS MAINLY DRY WITH BELOW NORMAL TEMPERATURES
FOR THE START OF THE WEEKEND.

THE FIRST OF TWO SYSTEMS OF CONCERN IN THE LONG RANGE WILL START TO
EFFECT THE WEATHER FOR SATURDAY. A PIECE OF ENERGY WILL MOVE OFF A
CUT OFF LOW OVER CALIFORNIA AND MOVE INTO THE ROCKIES. HOWEVER...IT
APPEARS THAT THE BEST UPPER LEVEL SUPPORT WILL REMAIN OVER UTAH AND
COLORADO. AT AS RESULT...RIGHT NOW THIS LOOKS TO MAINLY A NUISANCE
EVENT AND ONLY EFFECT SOUTHERN PORTIONS OF THE COUNTY WARNING AREA
AND MAINLY WEST OF THE DIVIDE. BOTH THE GFS...EUROPEAN AND NAM ARE
IN GOOD AGREEMENT OF THIS. AS A RESULT...WE TRIMMED POPS ACROSS
AREAS NORTH AND EAST OF THE WIND RIVER RANGE FOR SATURDAY AND
SATURDAY NIGHT. EVEN IN AREAS THAT GET SNOW...THIS DOES NOT LOOK
WORTHY OF ANY SORT OF WARNINGS OR ADVISORIES RIGHT NOW. ON
SUNDAY...THERE IS SOME SLIGHT DISAGREEMENT WITH THE GFS KEEPING A
FEW SHOWERS ALONG THE SOUTHERN BORDER AND THE EUROPEAN MAINLY DRY.
WITH THE DIFFERENCES WE MADE FEW CHANGES TO CONTINUITY. MAINLY DRY
BUT CONTINUED CHILLY WEATHER WILL BE THE RULE FOR MONDAY WITH WEAK
SURFACE HIGH PRESSURE IN CONTROL.

THE NEXT AND PROBABLY MORE IMPACTFUL SYSTEM THEN APPROACHES FOR
MONDAY NIGHT AND ESPECIALLY FOR TUESDAY. THIS ONE HAS CHILLY ORIGINS
COMING IN FROM ALASKA.  THE MODELS AGAIN ARE IN FAIRLY GOOD
AGREEMENT WITH SNOW BEGINNING IN THE WEST ON MONDAY NIGHT AND THEN
SPREADING ACROSS ALL AREAS FOR TUESDAY. THE PREVIOUS FORECAST HAD
CHANCE POPS ACROSS MOST AREAS AND THESE LOOK PRETTY GOOD AT THIS
POINT SO FEW CHANGES WERE MADE. SNOWFALL AMOUNTS ARE STILL UNCERTAIN
RIGHT NOW...AS A LOT WILL DEPEND ON THE JET DYNAMICS AND OF COURSE
THE MODELS ARE PERFECT WITH THIS FIVE DAYS OUT...NOTE SARCASM. THERE
IS ALSO MORE AGREEMENT WITH THE END TIME. THE EUROPEAN HAS COME
AROUND TO THE MORE PROGRESSIVE GFS SOLUTION IN KICKING THE SYSTEM TO
THE SOUTH AND EAST DURING WEDNESDAY WITH ALL AREAS DRY AT THAT
POINT. TUESDAY NIGHT AND WEDNESDAY HAVE THE POTENTIAL TO QUITE COLD.
LOWS TUESDAY NIGHT MAY DEPEND ON HOW QUICKLY THE SKY CLEARS THOUGH.
MAINLY DRY BUT COOL WEATHER WILL BE THE RULE FOR WEDNESDAY INTO
THURSDAY WITH DRY NORTHWEST FLOW PREDOMINATING.

&&

.AVIATION.../06Z ISSUANCE/

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

VFR TO MVFR CONDITIONS WILL OCCUR OVERNIGHT WITH LINGERING LIGHT
SNOW OR FLURRIES UNTIL 12Z. AFTER 12Z VFR CONDITIONS ARE EXPECTED
THROUGH 00Z SATURDAY. CLOUDS WILL LOWER OVER NORTHERN WY AFTER 00Z
SATURDAY WITH AREAS OF MVFR CONDITIONS OCCURRING THROUGH 06Z
SATURDAY.

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

VFR TO MVFR CONDITIONS WILL OCCUR OVERNIGHT IN SOUTHWEST WY WHERE
LOWER CLOUDS AND LINGERING LIGHT SNOW OR FLURRIES WILL OCCUR THROUGH
12Z. LOCAL IFR CONDITIONS ARE POSSIBLE. CONDITIONS IN SOUTHWEST WY
WILL IMPROVE TO VFR BY 16Z AND VFR CONDITIONS WILL PREVAIL UNTIL 06Z
SATURDAY.

FOR THE KJAC TERMINAL SITE VFR CONDITIONS ARE FORECAST THROUGH 16Z.
THEN MVFR CONDITIONS WILL PREVAIL AROUND 18Z THROUGH 06Z SATURDAY AS
LIGHT SNOW DEVELOPS OVER NORTHWEST WY BY 18Z AND CONTINUES THROUGH
06Z SATURDAY. EXPECT MOUNTAIN OBSCURATION AT TIMES IN NW WY.

&&

.FIRE WEATHER...

NO FIRE WEATHER CONCERNS IN THE SHORT TERM...AS A COLD WEATHER
PATTERN CONTINUES FOR THE ENTIRE DISTRICT. LITTLE OR NO
PRECIPITATION THROUGH THE UPCOMING WEEKEND EAST OF THE DIVIDE...
BUT RELATIVE HUMIDITIES TO REMAIN HIGH.

WEST OF THE DIVIDE...INCREASING CLOUDS CAN BE EXPECTED ON FRIDAY.
A WEAK UPPER LEVEL TROUGH WILL MOVE OVER THE WESTERN MOUNTAINS LATE
FRIDAY TO HELP INITIATE SNOW SHOWERS. AREAS OF LIGHT SNOW WILL
PERSIST FRIDAY NIGHT...POSSIBLY REACHING THE WESTERN VALLEYS OF
WYOMING.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...KPL
LONG TERM...HATTINGS
AVIATION...AR
FIRE WEATHER...KPL








000
FXUS63 KUNR 270449
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
949 PM MST THU FEB 26 2015

.UPDATE...
ISSUED AT 741 PM MST THU FEB 26 2015

TEMPS HAVE FALLEN TO OR SLIGHTLY BELOW FCST MINS IN PARTS OF NERN
WY AND THE BLKHLS SO HAVE UPDATED FCST ACCORDINGLY. WARM ADVECTION
OVERNIGHT IN OUR FAR WRN ZONES SHOULD LIMIT HOW MUCH FURTHER TEMPS
WILL FALL.

&&

.SHORT TERM...THIS EVENING THROUGH FRIDAY NIGHT
ISSUED AT 207 PM MST THU FEB 26 2015

BROAD UPPER TROUGH REMAINS ACROSS MUCH OF THE CONUS...WITH NW FLOW
CONTINUING ACROSS THE REGION. ARCTIC HIGH PRESSURE SITS ACROSS THE
NRN PLAINS WITH MUCH COLDER TEMPS ACROSS THE DAKOTAS. HIGHS ACROSS
THE CWA SO FAR TODAY HAVE REACHED THE SINGLE DIGITS TO LOWER TEENS.
NW WINDS ACROSS THE WRN SD PLAINS ARE GENERALLY BLOWING AT 10 TO 15
MPH...WHILE LIGHTER OVER NE WY. RADAR SHOWING LIGHT SHSN ACROSS THE
BLACK HILLS PORTIONS OF CUSTER COUNTY.

SHSN WILL END TONIGHT AS SKIES CONTINUE TO CLEAR AREAWIDE. LOWS WILL
DROP TO ZERO TO 10 BELOW. SURFACE HIGH PRESSURE WILL SLIDE JUST EAST
OF THE AREA SETTING UP RETURN FLOW OVER THE CWA TONIGHT INTO FRIDAY.
SE WINDS WILL INCREASE THROUGH THE NIGHT PARTICULARLY OVER THE NE WY
PLAINS MAINLY AFTER 06Z. THESE WINDS WILL ALSO HELP RAISE TEMPS
SLIGHTLY. WIND CHILLS OF 10 BELOW TO 20 BELOW ZERO ARE EXPECTED
EARLY FRI MORNING.

OTHER THAN SOME PASSING CLOUDS ACROSS SW/SCNTRL SD...MOSTLY SUNNY
SKIES ARE EXPECTED FRIDAY. RETURN FLOW PRESSURE GRADIENT WILL
INCREASE THROUGH THE DAY WITH SE WINDS INCREASING TO 10 TO 20 MPH
OVER THE WRN SD PLAINS...AND CONTINUING OVER THE NE WY PLAINS. HIGHS
WILL BE WARMER...BUT STILL BELOW SEASONAL AVERAGES...REACHING THE
20S TO LOWER 30S OVER MOST LOCATIONS.

.LONG TERM...SATURDAY THROUGH THURSDAY
ISSUED AT 207 PM MST THU FEB 26 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND AS AN UPPER TROUGH AND SURFACE HIGH REMAINS ACROSS THE
REGION. THE SURFACE HIGH WILL MOVE EAST MONDAY AS THE UPPER FLOW
BECOMES MORE WESTERLY AND WARMER PACIFIC SOURCED AIR PUSHES INTO
THE NORTHERN PLAINS. THE MODELS STILL AGREE ON A BRIEF WARMUP
MONDAY. A LARGE STORM SYSTEM WILL DEVELOPS ACROSS THE CNTRL
PORTIONS OF THE CONUS TUESDAY. ARCTIC AIR WILL BE DRAWN IN BEHIND
THE STORM OVER THE REGION. HAVE LOWERED TUESDAY HIGHS SOME MORE
OVER NE WY AND NW SD. THE TROUGH AXIS CROSSING THE REGION WILL
ALSO BRING A CHANCE OF SNOW TO MUCH OF THE AREA TUE/TUE NIGHT.
WARMER AND DRIER WEATHER IS EXPECTED FOR THE SECOND HALF OF THE
WEEK AS A STRONG UPPER RIDGE BEGINS BUILDING IN FROM THE WEST.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 947 PM MST THU FEB 26 2015

A FEW LINGERING MVFR CIGS EXPECTED AROUND THE BLKHLS OVERNIGHT.
OTHERWISE...VFR CONDITIONS EXPECTED.


&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

UPDATE...JOHNSON
SHORT TERM...13
LONG TERM...13
AVIATION...JOHNSON







000
FXUS63 KUNR 270449
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
949 PM MST THU FEB 26 2015

.UPDATE...
ISSUED AT 741 PM MST THU FEB 26 2015

TEMPS HAVE FALLEN TO OR SLIGHTLY BELOW FCST MINS IN PARTS OF NERN
WY AND THE BLKHLS SO HAVE UPDATED FCST ACCORDINGLY. WARM ADVECTION
OVERNIGHT IN OUR FAR WRN ZONES SHOULD LIMIT HOW MUCH FURTHER TEMPS
WILL FALL.

&&

.SHORT TERM...THIS EVENING THROUGH FRIDAY NIGHT
ISSUED AT 207 PM MST THU FEB 26 2015

BROAD UPPER TROUGH REMAINS ACROSS MUCH OF THE CONUS...WITH NW FLOW
CONTINUING ACROSS THE REGION. ARCTIC HIGH PRESSURE SITS ACROSS THE
NRN PLAINS WITH MUCH COLDER TEMPS ACROSS THE DAKOTAS. HIGHS ACROSS
THE CWA SO FAR TODAY HAVE REACHED THE SINGLE DIGITS TO LOWER TEENS.
NW WINDS ACROSS THE WRN SD PLAINS ARE GENERALLY BLOWING AT 10 TO 15
MPH...WHILE LIGHTER OVER NE WY. RADAR SHOWING LIGHT SHSN ACROSS THE
BLACK HILLS PORTIONS OF CUSTER COUNTY.

SHSN WILL END TONIGHT AS SKIES CONTINUE TO CLEAR AREAWIDE. LOWS WILL
DROP TO ZERO TO 10 BELOW. SURFACE HIGH PRESSURE WILL SLIDE JUST EAST
OF THE AREA SETTING UP RETURN FLOW OVER THE CWA TONIGHT INTO FRIDAY.
SE WINDS WILL INCREASE THROUGH THE NIGHT PARTICULARLY OVER THE NE WY
PLAINS MAINLY AFTER 06Z. THESE WINDS WILL ALSO HELP RAISE TEMPS
SLIGHTLY. WIND CHILLS OF 10 BELOW TO 20 BELOW ZERO ARE EXPECTED
EARLY FRI MORNING.

OTHER THAN SOME PASSING CLOUDS ACROSS SW/SCNTRL SD...MOSTLY SUNNY
SKIES ARE EXPECTED FRIDAY. RETURN FLOW PRESSURE GRADIENT WILL
INCREASE THROUGH THE DAY WITH SE WINDS INCREASING TO 10 TO 20 MPH
OVER THE WRN SD PLAINS...AND CONTINUING OVER THE NE WY PLAINS. HIGHS
WILL BE WARMER...BUT STILL BELOW SEASONAL AVERAGES...REACHING THE
20S TO LOWER 30S OVER MOST LOCATIONS.

.LONG TERM...SATURDAY THROUGH THURSDAY
ISSUED AT 207 PM MST THU FEB 26 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND AS AN UPPER TROUGH AND SURFACE HIGH REMAINS ACROSS THE
REGION. THE SURFACE HIGH WILL MOVE EAST MONDAY AS THE UPPER FLOW
BECOMES MORE WESTERLY AND WARMER PACIFIC SOURCED AIR PUSHES INTO
THE NORTHERN PLAINS. THE MODELS STILL AGREE ON A BRIEF WARMUP
MONDAY. A LARGE STORM SYSTEM WILL DEVELOPS ACROSS THE CNTRL
PORTIONS OF THE CONUS TUESDAY. ARCTIC AIR WILL BE DRAWN IN BEHIND
THE STORM OVER THE REGION. HAVE LOWERED TUESDAY HIGHS SOME MORE
OVER NE WY AND NW SD. THE TROUGH AXIS CROSSING THE REGION WILL
ALSO BRING A CHANCE OF SNOW TO MUCH OF THE AREA TUE/TUE NIGHT.
WARMER AND DRIER WEATHER IS EXPECTED FOR THE SECOND HALF OF THE
WEEK AS A STRONG UPPER RIDGE BEGINS BUILDING IN FROM THE WEST.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 947 PM MST THU FEB 26 2015

A FEW LINGERING MVFR CIGS EXPECTED AROUND THE BLKHLS OVERNIGHT.
OTHERWISE...VFR CONDITIONS EXPECTED.


&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

UPDATE...JOHNSON
SHORT TERM...13
LONG TERM...13
AVIATION...JOHNSON






000
FXUS63 KUNR 270244
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
744 PM MST THU FEB 26 2015

.UPDATE...
ISSUED AT 741 PM MST THU FEB 26 2015

TEMPS HAVE FALLEN TO OR SLIGHTLY BELOW FCST MINS IN PARTS OF NERN
WY AND THE BLKHLS SO HAVE UPDATED FCST ACCORDINGLY. WARM ADVECTION
OVERNIGHT IN OUR FAR WRN ZONES SHOULD LIMIT HOW MUCH FURTHER TEMPS
WILL FALL.

&&

.SHORT TERM...THIS EVENING THROUGH FRIDAY NIGHT
ISSUED AT 207 PM MST THU FEB 26 2015

BROAD UPPER TROUGH REMAINS ACROSS MUCH OF THE CONUS...WITH NW FLOW
CONTINUING ACROSS THE REGION. ARCTIC HIGH PRESSURE SITS ACROSS THE
NRN PLAINS WITH MUCH COLDER TEMPS ACROSS THE DAKOTAS. HIGHS ACROSS
THE CWA SO FAR TODAY HAVE REACHED THE SINGLE DIGITS TO LOWER TEENS.
NW WINDS ACROSS THE WRN SD PLAINS ARE GENERALLY BLOWING AT 10 TO 15
MPH...WHILE LIGHTER OVER NE WY. RADAR SHOWING LIGHT SHSN ACROSS THE
BLACK HILLS PORTIONS OF CUSTER COUNTY.

SHSN WILL END TONIGHT AS SKIES CONTINUE TO CLEAR AREAWIDE. LOWS WILL
DROP TO ZERO TO 10 BELOW. SURFACE HIGH PRESSURE WILL SLIDE JUST EAST
OF THE AREA SETTING UP RETURN FLOW OVER THE CWA TONIGHT INTO FRIDAY.
SE WINDS WILL INCREASE THROUGH THE NIGHT PARTICULARLY OVER THE NE WY
PLAINS MAINLY AFTER 06Z. THESE WINDS WILL ALSO HELP RAISE TEMPS
SLIGHTLY. WIND CHILLS OF 10 BELOW TO 20 BELOW ZERO ARE EXPECTED
EARLY FRI MORNING.

OTHER THAN SOME PASSING CLOUDS ACROSS SW/SCNTRL SD...MOSTLY SUNNY
SKIES ARE EXPECTED FRIDAY. RETURN FLOW PRESSURE GRADIENT WILL
INCREASE THROUGH THE DAY WITH SE WINDS INCREASING TO 10 TO 20 MPH
OVER THE WRN SD PLAINS...AND CONTINUING OVER THE NE WY PLAINS. HIGHS
WILL BE WARMER...BUT STILL BELOW SEASONAL AVERAGES...REACHING THE
20S TO LOWER 30S OVER MOST LOCATIONS.

.LONG TERM...SATURDAY THROUGH THURSDAY
ISSUED AT 207 PM MST THU FEB 26 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND AS AN UPPER TROUGH AND SURFACE HIGH REMAINS ACROSS THE
REGION. THE SURFACE HIGH WILL MOVE EAST MONDAY AS THE UPPER FLOW
BECOMES MORE WESTERLY AND WARMER PACIFIC SOURCED AIR PUSHES INTO
THE NORTHERN PLAINS. THE MODELS STILL AGREE ON A BRIEF WARMUP
MONDAY. A LARGE STORM SYSTEM WILL DEVELOPS ACROSS THE CNTRL
PORTIONS OF THE CONUS TUESDAY. ARCTIC AIR WILL BE DRAWN IN BEHIND
THE STORM OVER THE REGION. HAVE LOWERED TUESDAY HIGHS SOME MORE
OVER NE WY AND NW SD. THE TROUGH AXIS CROSSING THE REGION WILL
ALSO BRING A CHANCE OF SNOW TO MUCH OF THE AREA TUE/TUE NIGHT.
WARMER AND DRIER WEATHER IS EXPECTED FOR THE SECOND HALF OF THE
WEEK AS A STRONG UPPER RIDGE BEGINS BUILDING IN FROM THE WEST.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING
ISSUED AT 207 PM MST THU FEB 26 2015

MVFR CIGS ACROSS THE SRN BLKHLS ASSOCIATED WITH -SHSN WILL
DISSIPATE EARLY THIS EVENING...WITH CONDITIONS BECOMING VFR. VFR
EXPECTED ELSEWHERE.


&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

UPDATE...JOHNSON
SHORT TERM...13
LONG TERM...13
AVIATION...7







000
FXUS63 KUNR 270244
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
744 PM MST THU FEB 26 2015

.UPDATE...
ISSUED AT 741 PM MST THU FEB 26 2015

TEMPS HAVE FALLEN TO OR SLIGHTLY BELOW FCST MINS IN PARTS OF NERN
WY AND THE BLKHLS SO HAVE UPDATED FCST ACCORDINGLY. WARM ADVECTION
OVERNIGHT IN OUR FAR WRN ZONES SHOULD LIMIT HOW MUCH FURTHER TEMPS
WILL FALL.

&&

.SHORT TERM...THIS EVENING THROUGH FRIDAY NIGHT
ISSUED AT 207 PM MST THU FEB 26 2015

BROAD UPPER TROUGH REMAINS ACROSS MUCH OF THE CONUS...WITH NW FLOW
CONTINUING ACROSS THE REGION. ARCTIC HIGH PRESSURE SITS ACROSS THE
NRN PLAINS WITH MUCH COLDER TEMPS ACROSS THE DAKOTAS. HIGHS ACROSS
THE CWA SO FAR TODAY HAVE REACHED THE SINGLE DIGITS TO LOWER TEENS.
NW WINDS ACROSS THE WRN SD PLAINS ARE GENERALLY BLOWING AT 10 TO 15
MPH...WHILE LIGHTER OVER NE WY. RADAR SHOWING LIGHT SHSN ACROSS THE
BLACK HILLS PORTIONS OF CUSTER COUNTY.

SHSN WILL END TONIGHT AS SKIES CONTINUE TO CLEAR AREAWIDE. LOWS WILL
DROP TO ZERO TO 10 BELOW. SURFACE HIGH PRESSURE WILL SLIDE JUST EAST
OF THE AREA SETTING UP RETURN FLOW OVER THE CWA TONIGHT INTO FRIDAY.
SE WINDS WILL INCREASE THROUGH THE NIGHT PARTICULARLY OVER THE NE WY
PLAINS MAINLY AFTER 06Z. THESE WINDS WILL ALSO HELP RAISE TEMPS
SLIGHTLY. WIND CHILLS OF 10 BELOW TO 20 BELOW ZERO ARE EXPECTED
EARLY FRI MORNING.

OTHER THAN SOME PASSING CLOUDS ACROSS SW/SCNTRL SD...MOSTLY SUNNY
SKIES ARE EXPECTED FRIDAY. RETURN FLOW PRESSURE GRADIENT WILL
INCREASE THROUGH THE DAY WITH SE WINDS INCREASING TO 10 TO 20 MPH
OVER THE WRN SD PLAINS...AND CONTINUING OVER THE NE WY PLAINS. HIGHS
WILL BE WARMER...BUT STILL BELOW SEASONAL AVERAGES...REACHING THE
20S TO LOWER 30S OVER MOST LOCATIONS.

.LONG TERM...SATURDAY THROUGH THURSDAY
ISSUED AT 207 PM MST THU FEB 26 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND AS AN UPPER TROUGH AND SURFACE HIGH REMAINS ACROSS THE
REGION. THE SURFACE HIGH WILL MOVE EAST MONDAY AS THE UPPER FLOW
BECOMES MORE WESTERLY AND WARMER PACIFIC SOURCED AIR PUSHES INTO
THE NORTHERN PLAINS. THE MODELS STILL AGREE ON A BRIEF WARMUP
MONDAY. A LARGE STORM SYSTEM WILL DEVELOPS ACROSS THE CNTRL
PORTIONS OF THE CONUS TUESDAY. ARCTIC AIR WILL BE DRAWN IN BEHIND
THE STORM OVER THE REGION. HAVE LOWERED TUESDAY HIGHS SOME MORE
OVER NE WY AND NW SD. THE TROUGH AXIS CROSSING THE REGION WILL
ALSO BRING A CHANCE OF SNOW TO MUCH OF THE AREA TUE/TUE NIGHT.
WARMER AND DRIER WEATHER IS EXPECTED FOR THE SECOND HALF OF THE
WEEK AS A STRONG UPPER RIDGE BEGINS BUILDING IN FROM THE WEST.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING
ISSUED AT 207 PM MST THU FEB 26 2015

MVFR CIGS ACROSS THE SRN BLKHLS ASSOCIATED WITH -SHSN WILL
DISSIPATE EARLY THIS EVENING...WITH CONDITIONS BECOMING VFR. VFR
EXPECTED ELSEWHERE.


&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

UPDATE...JOHNSON
SHORT TERM...13
LONG TERM...13
AVIATION...7






000
FXUS63 KUNR 270244
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
744 PM MST THU FEB 26 2015

.UPDATE...
ISSUED AT 741 PM MST THU FEB 26 2015

TEMPS HAVE FALLEN TO OR SLIGHTLY BELOW FCST MINS IN PARTS OF NERN
WY AND THE BLKHLS SO HAVE UPDATED FCST ACCORDINGLY. WARM ADVECTION
OVERNIGHT IN OUR FAR WRN ZONES SHOULD LIMIT HOW MUCH FURTHER TEMPS
WILL FALL.

&&

.SHORT TERM...THIS EVENING THROUGH FRIDAY NIGHT
ISSUED AT 207 PM MST THU FEB 26 2015

BROAD UPPER TROUGH REMAINS ACROSS MUCH OF THE CONUS...WITH NW FLOW
CONTINUING ACROSS THE REGION. ARCTIC HIGH PRESSURE SITS ACROSS THE
NRN PLAINS WITH MUCH COLDER TEMPS ACROSS THE DAKOTAS. HIGHS ACROSS
THE CWA SO FAR TODAY HAVE REACHED THE SINGLE DIGITS TO LOWER TEENS.
NW WINDS ACROSS THE WRN SD PLAINS ARE GENERALLY BLOWING AT 10 TO 15
MPH...WHILE LIGHTER OVER NE WY. RADAR SHOWING LIGHT SHSN ACROSS THE
BLACK HILLS PORTIONS OF CUSTER COUNTY.

SHSN WILL END TONIGHT AS SKIES CONTINUE TO CLEAR AREAWIDE. LOWS WILL
DROP TO ZERO TO 10 BELOW. SURFACE HIGH PRESSURE WILL SLIDE JUST EAST
OF THE AREA SETTING UP RETURN FLOW OVER THE CWA TONIGHT INTO FRIDAY.
SE WINDS WILL INCREASE THROUGH THE NIGHT PARTICULARLY OVER THE NE WY
PLAINS MAINLY AFTER 06Z. THESE WINDS WILL ALSO HELP RAISE TEMPS
SLIGHTLY. WIND CHILLS OF 10 BELOW TO 20 BELOW ZERO ARE EXPECTED
EARLY FRI MORNING.

OTHER THAN SOME PASSING CLOUDS ACROSS SW/SCNTRL SD...MOSTLY SUNNY
SKIES ARE EXPECTED FRIDAY. RETURN FLOW PRESSURE GRADIENT WILL
INCREASE THROUGH THE DAY WITH SE WINDS INCREASING TO 10 TO 20 MPH
OVER THE WRN SD PLAINS...AND CONTINUING OVER THE NE WY PLAINS. HIGHS
WILL BE WARMER...BUT STILL BELOW SEASONAL AVERAGES...REACHING THE
20S TO LOWER 30S OVER MOST LOCATIONS.

.LONG TERM...SATURDAY THROUGH THURSDAY
ISSUED AT 207 PM MST THU FEB 26 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND AS AN UPPER TROUGH AND SURFACE HIGH REMAINS ACROSS THE
REGION. THE SURFACE HIGH WILL MOVE EAST MONDAY AS THE UPPER FLOW
BECOMES MORE WESTERLY AND WARMER PACIFIC SOURCED AIR PUSHES INTO
THE NORTHERN PLAINS. THE MODELS STILL AGREE ON A BRIEF WARMUP
MONDAY. A LARGE STORM SYSTEM WILL DEVELOPS ACROSS THE CNTRL
PORTIONS OF THE CONUS TUESDAY. ARCTIC AIR WILL BE DRAWN IN BEHIND
THE STORM OVER THE REGION. HAVE LOWERED TUESDAY HIGHS SOME MORE
OVER NE WY AND NW SD. THE TROUGH AXIS CROSSING THE REGION WILL
ALSO BRING A CHANCE OF SNOW TO MUCH OF THE AREA TUE/TUE NIGHT.
WARMER AND DRIER WEATHER IS EXPECTED FOR THE SECOND HALF OF THE
WEEK AS A STRONG UPPER RIDGE BEGINS BUILDING IN FROM THE WEST.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING
ISSUED AT 207 PM MST THU FEB 26 2015

MVFR CIGS ACROSS THE SRN BLKHLS ASSOCIATED WITH -SHSN WILL
DISSIPATE EARLY THIS EVENING...WITH CONDITIONS BECOMING VFR. VFR
EXPECTED ELSEWHERE.


&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

UPDATE...JOHNSON
SHORT TERM...13
LONG TERM...13
AVIATION...7






000
FXUS63 KUNR 270244
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
744 PM MST THU FEB 26 2015

.UPDATE...
ISSUED AT 741 PM MST THU FEB 26 2015

TEMPS HAVE FALLEN TO OR SLIGHTLY BELOW FCST MINS IN PARTS OF NERN
WY AND THE BLKHLS SO HAVE UPDATED FCST ACCORDINGLY. WARM ADVECTION
OVERNIGHT IN OUR FAR WRN ZONES SHOULD LIMIT HOW MUCH FURTHER TEMPS
WILL FALL.

&&

.SHORT TERM...THIS EVENING THROUGH FRIDAY NIGHT
ISSUED AT 207 PM MST THU FEB 26 2015

BROAD UPPER TROUGH REMAINS ACROSS MUCH OF THE CONUS...WITH NW FLOW
CONTINUING ACROSS THE REGION. ARCTIC HIGH PRESSURE SITS ACROSS THE
NRN PLAINS WITH MUCH COLDER TEMPS ACROSS THE DAKOTAS. HIGHS ACROSS
THE CWA SO FAR TODAY HAVE REACHED THE SINGLE DIGITS TO LOWER TEENS.
NW WINDS ACROSS THE WRN SD PLAINS ARE GENERALLY BLOWING AT 10 TO 15
MPH...WHILE LIGHTER OVER NE WY. RADAR SHOWING LIGHT SHSN ACROSS THE
BLACK HILLS PORTIONS OF CUSTER COUNTY.

SHSN WILL END TONIGHT AS SKIES CONTINUE TO CLEAR AREAWIDE. LOWS WILL
DROP TO ZERO TO 10 BELOW. SURFACE HIGH PRESSURE WILL SLIDE JUST EAST
OF THE AREA SETTING UP RETURN FLOW OVER THE CWA TONIGHT INTO FRIDAY.
SE WINDS WILL INCREASE THROUGH THE NIGHT PARTICULARLY OVER THE NE WY
PLAINS MAINLY AFTER 06Z. THESE WINDS WILL ALSO HELP RAISE TEMPS
SLIGHTLY. WIND CHILLS OF 10 BELOW TO 20 BELOW ZERO ARE EXPECTED
EARLY FRI MORNING.

OTHER THAN SOME PASSING CLOUDS ACROSS SW/SCNTRL SD...MOSTLY SUNNY
SKIES ARE EXPECTED FRIDAY. RETURN FLOW PRESSURE GRADIENT WILL
INCREASE THROUGH THE DAY WITH SE WINDS INCREASING TO 10 TO 20 MPH
OVER THE WRN SD PLAINS...AND CONTINUING OVER THE NE WY PLAINS. HIGHS
WILL BE WARMER...BUT STILL BELOW SEASONAL AVERAGES...REACHING THE
20S TO LOWER 30S OVER MOST LOCATIONS.

.LONG TERM...SATURDAY THROUGH THURSDAY
ISSUED AT 207 PM MST THU FEB 26 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND AS AN UPPER TROUGH AND SURFACE HIGH REMAINS ACROSS THE
REGION. THE SURFACE HIGH WILL MOVE EAST MONDAY AS THE UPPER FLOW
BECOMES MORE WESTERLY AND WARMER PACIFIC SOURCED AIR PUSHES INTO
THE NORTHERN PLAINS. THE MODELS STILL AGREE ON A BRIEF WARMUP
MONDAY. A LARGE STORM SYSTEM WILL DEVELOPS ACROSS THE CNTRL
PORTIONS OF THE CONUS TUESDAY. ARCTIC AIR WILL BE DRAWN IN BEHIND
THE STORM OVER THE REGION. HAVE LOWERED TUESDAY HIGHS SOME MORE
OVER NE WY AND NW SD. THE TROUGH AXIS CROSSING THE REGION WILL
ALSO BRING A CHANCE OF SNOW TO MUCH OF THE AREA TUE/TUE NIGHT.
WARMER AND DRIER WEATHER IS EXPECTED FOR THE SECOND HALF OF THE
WEEK AS A STRONG UPPER RIDGE BEGINS BUILDING IN FROM THE WEST.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING
ISSUED AT 207 PM MST THU FEB 26 2015

MVFR CIGS ACROSS THE SRN BLKHLS ASSOCIATED WITH -SHSN WILL
DISSIPATE EARLY THIS EVENING...WITH CONDITIONS BECOMING VFR. VFR
EXPECTED ELSEWHERE.


&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

UPDATE...JOHNSON
SHORT TERM...13
LONG TERM...13
AVIATION...7







000
FXUS65 KCYS 270009
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
509 PM MST THU FEB 26 2015

.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 318 PM MST THU FEB 26 2015

ONGOING UPSLOPE SNOW EVENT IS THE MAIN CONCERN INITIALLY.
VISIBILITIES HAVE BEEN THE LOWEST AND SNOWFALL RATES THE HIGHEST
AT CHEYENNE REALLY ALL DAY LONG. THIS AS LLVL EASTERLY UPSLOPE
FLOW INTERACTS WITH THE FAVORABLE LEADING EDGE OF SHORTWAVE ENERGY
DIVING SOUTHEAST INTO THE HIGH PLAINS/FRONT RANGE. 12/18Z MODELS
SHOW LLVL LIFT INCREASING ACROSS LARAMIE COUNTY THRU THE REST OF
THE EVENING HOURS. MODELS HAVE CONTINUED TO TREND SNOWFALL AMOUNTS
UP ACROSS CENTRAL/SOUTHERN LARAMIE COUNTY ESPECIALLY FOR THIS
EVENING. SO IN AN EARLIER UPDATE...OPTED TO ISSUE A WINTER WEATHER
ADVISORY FOR CENTRAL LARAMIE COUNTY INCLUDING WRN FOOTHILLS
LOCATIONS EFFECTIVE THRU 10Z FRIDAY. EXPECT GENERALLY 2 TO 4
INCHES TO FALL...WITH THE HIGHEST AMOUNTS IN AREAS NEAREST THE
CHEYENNE RIDGE. LIFT/SNOW WILL DIMINISH SIGNIFICANTLY WITH THE
PASSAGE OF THE MID-LEVEL/H5 TROUGH FRIDAY 09-12Z. AMOUNTS WILL BE
SIGNIFICANTLY LIGHTER OUTSIDE OF LARAMIE COUNTY WITH THIS
SYSTEM...WITH PERHAPS AN INCH OR SO AT LARAMIE... WHEATLAND AND
KIMBALL. RAWLINS AND LOCATIONS TO THE NORTH OF THE NORTH PLATTE
RIVER VALLEY WILL SEE NOTHING AT ALL OR JUST SOME FLURRIES.
FORTUNATELY WINDS ARE ONLY PROGD TO BE AROUND 10 KNOTS...SO DONT
EXPECT BLOWING SNOW TO BE A CONCERN. ANOTHER COLD NIGHT AHEAD WITH
LOWS FALLING INTO THE SINGLE DIGITS OR SINGLE DIGITS BELOW ZERO.

QUICK SHORTWAVE RIDGE AXIS WILL USHER IN A MOSTLY DRY DAY FOR
FRIDAY WITH PERHAPS A FEW DEGREES OF WARMING BENEATH A VERY BRIEF
LLVL THERMAL RIDGING. EVEN SO HIGHS ON FRIDAY WILL ONLY REACH THE
TEENS AND 20S.

THE NEXT COLD FRONT WILL SLIDE FROM NORTH TO SOUTH DURING THE DAY
ON SATURDAY AS THE PATTERN FLATTENS AHEAD OF THE FORMING CUT-OFF
OVR THE GREAT BASIN. MOISTURE WILL BE LIMITED INITIALLY ON
SATURDAY AWAITING THE ARRIVAL OF AN EJECTING SHORTWAVE ENERGY AND
RESULTANT FAVORABLE ISENTROPIC LIFT/OVERRUNNING SET-UP. SNOW WILL
OVERSPREAD MUCH OF THE SOUTHERN TIER OF COUNTIES LATE SATURDAY AND
ESPECIALLY SATURDAY NIGHT. ALTHOUGH EXPECT THE BULK OF THE BEST
LIFT TO REMAIN SOUTH OVER COLORADO...SHOULD SEE SOME AT LEAST
LIGHT ACCUMULATIONS ESPECIALLY ALONG THE I80 CORRIDOR.

.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 318 PM MST THU FEB 26 2015

A RATHER COLD PATTERN EXPECTED TO PERSIST OVER THE REGION FOR MOST
OF THIS PERIOD WITH MONDAY LIKELY BEING THE MILDEST DAY THIS
PERIOD. INITIALLY THE CWA WILL BE UNDER CONFLUENT UPPER FLOW
BETWEEN ONE STREAM EMANATING FROM WESTERN CANADA INTO THE
NORTHERN PLAINS AND THE OTHER FROM THE SOUTHWEST CONUS AHEAD OF AN
UPPER LOW OFF THE CAL COAST. STILL CHILLY ACROSS THE AREA SUNDAY
AS A COLD SFC HIGH OVER THE HIGH PLAINS SHIFTS EAST DURING THE
DAY. A SHORTWAVE WILL MOVE INTO THE PACIFIC NW ON MONDAY AND PHASE
WITH THE CALIFORNIA UPPER LOW CREATING A LARGER SCALE UPPER TROF
OVER THE WESTERN CONUS MONDAY NIGHT. AT THE SAME TIME LEE TROFFING
WILL DEVELOP OVER THE HIGH PLAINS WHICH WILL SCOUR OUT THE COLDER
AIR AND BRING A SHORT PERIOD OF WARMING TO THE CWA FOR MONDAY.
MOISTURE FROM THE SOUTHWEST SHOULD GET CAUGHT UP IN THE SWLY FLOW
AHEAD OF THE UPPER TROF AND ADVECT OVER THE CWA MONDAY NIGHT AND
TUESDAY. THE NEXT SURGE OF COLD AIR WILL THEN DROP SOUTH OVER THE
HIGH PLAINS EARLY TUESDAY AND WILL AID IN THE DEVELOPMENT OF SNOW
OVER THE REGION TUESDAY INTO TUESDAY NIGHT. QUITE COLD AGAIN WEDS
WITH SNOW ENDING EARLY AS THE SURFACE HIGH SETTLES ACROSS WY AND
THE MAIN UPPER TROF AXIS PASSES ACROSS LEAVING A NW FLOW ALOFT
OVER THE REGION. MAINLY DRY THURSDAY WITH WARMER TEMPS AGAIN AS
DOWNSLOPE FLOW RETURNS.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 506 PM MST THU FEB 26 2015

ATTENTION MAINLY ON KCYS AND KLAR TONIGHT AS A WEAK FRONT MOVES
INTO NORTHWESTERN COLORADO. EASTERLY UPSLOPING WINDS EAST OF THE
LARAMIE RANGE SHOULD KEEP KCYS IN IFR/LIFR CONDITIONS...WHILE THE
NORTHEASTERN EDGE OF SNOW WITH THE FRONT COULD IMPACT KLAR. WILL
CONTINUE TO MONITOR...BUT DO BELIEVE KCYS COULD STAY DOWN ALL DAY
FRIDAY WITH SOUTHEAST UPSLOPE WINDS.

&&

.FIRE WEATHER...
ISSUED AT 318 PM MST THU FEB 26 2015

COLD TEMPERATURES AND UNSETTLED CONDITIONS WILL SUPPRESS ANY FIRE
WEATHER CONCERNS FOR THE FORESEEABLE FUTURE.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 3 AM MST FRIDAY FOR WYZ117-118.

NE...NONE.
&&

$$

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




000
FXUS65 KCYS 270009
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
509 PM MST THU FEB 26 2015

.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 318 PM MST THU FEB 26 2015

ONGOING UPSLOPE SNOW EVENT IS THE MAIN CONCERN INITIALLY.
VISIBILITIES HAVE BEEN THE LOWEST AND SNOWFALL RATES THE HIGHEST
AT CHEYENNE REALLY ALL DAY LONG. THIS AS LLVL EASTERLY UPSLOPE
FLOW INTERACTS WITH THE FAVORABLE LEADING EDGE OF SHORTWAVE ENERGY
DIVING SOUTHEAST INTO THE HIGH PLAINS/FRONT RANGE. 12/18Z MODELS
SHOW LLVL LIFT INCREASING ACROSS LARAMIE COUNTY THRU THE REST OF
THE EVENING HOURS. MODELS HAVE CONTINUED TO TREND SNOWFALL AMOUNTS
UP ACROSS CENTRAL/SOUTHERN LARAMIE COUNTY ESPECIALLY FOR THIS
EVENING. SO IN AN EARLIER UPDATE...OPTED TO ISSUE A WINTER WEATHER
ADVISORY FOR CENTRAL LARAMIE COUNTY INCLUDING WRN FOOTHILLS
LOCATIONS EFFECTIVE THRU 10Z FRIDAY. EXPECT GENERALLY 2 TO 4
INCHES TO FALL...WITH THE HIGHEST AMOUNTS IN AREAS NEAREST THE
CHEYENNE RIDGE. LIFT/SNOW WILL DIMINISH SIGNIFICANTLY WITH THE
PASSAGE OF THE MID-LEVEL/H5 TROUGH FRIDAY 09-12Z. AMOUNTS WILL BE
SIGNIFICANTLY LIGHTER OUTSIDE OF LARAMIE COUNTY WITH THIS
SYSTEM...WITH PERHAPS AN INCH OR SO AT LARAMIE... WHEATLAND AND
KIMBALL. RAWLINS AND LOCATIONS TO THE NORTH OF THE NORTH PLATTE
RIVER VALLEY WILL SEE NOTHING AT ALL OR JUST SOME FLURRIES.
FORTUNATELY WINDS ARE ONLY PROGD TO BE AROUND 10 KNOTS...SO DONT
EXPECT BLOWING SNOW TO BE A CONCERN. ANOTHER COLD NIGHT AHEAD WITH
LOWS FALLING INTO THE SINGLE DIGITS OR SINGLE DIGITS BELOW ZERO.

QUICK SHORTWAVE RIDGE AXIS WILL USHER IN A MOSTLY DRY DAY FOR
FRIDAY WITH PERHAPS A FEW DEGREES OF WARMING BENEATH A VERY BRIEF
LLVL THERMAL RIDGING. EVEN SO HIGHS ON FRIDAY WILL ONLY REACH THE
TEENS AND 20S.

THE NEXT COLD FRONT WILL SLIDE FROM NORTH TO SOUTH DURING THE DAY
ON SATURDAY AS THE PATTERN FLATTENS AHEAD OF THE FORMING CUT-OFF
OVR THE GREAT BASIN. MOISTURE WILL BE LIMITED INITIALLY ON
SATURDAY AWAITING THE ARRIVAL OF AN EJECTING SHORTWAVE ENERGY AND
RESULTANT FAVORABLE ISENTROPIC LIFT/OVERRUNNING SET-UP. SNOW WILL
OVERSPREAD MUCH OF THE SOUTHERN TIER OF COUNTIES LATE SATURDAY AND
ESPECIALLY SATURDAY NIGHT. ALTHOUGH EXPECT THE BULK OF THE BEST
LIFT TO REMAIN SOUTH OVER COLORADO...SHOULD SEE SOME AT LEAST
LIGHT ACCUMULATIONS ESPECIALLY ALONG THE I80 CORRIDOR.

.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 318 PM MST THU FEB 26 2015

A RATHER COLD PATTERN EXPECTED TO PERSIST OVER THE REGION FOR MOST
OF THIS PERIOD WITH MONDAY LIKELY BEING THE MILDEST DAY THIS
PERIOD. INITIALLY THE CWA WILL BE UNDER CONFLUENT UPPER FLOW
BETWEEN ONE STREAM EMANATING FROM WESTERN CANADA INTO THE
NORTHERN PLAINS AND THE OTHER FROM THE SOUTHWEST CONUS AHEAD OF AN
UPPER LOW OFF THE CAL COAST. STILL CHILLY ACROSS THE AREA SUNDAY
AS A COLD SFC HIGH OVER THE HIGH PLAINS SHIFTS EAST DURING THE
DAY. A SHORTWAVE WILL MOVE INTO THE PACIFIC NW ON MONDAY AND PHASE
WITH THE CALIFORNIA UPPER LOW CREATING A LARGER SCALE UPPER TROF
OVER THE WESTERN CONUS MONDAY NIGHT. AT THE SAME TIME LEE TROFFING
WILL DEVELOP OVER THE HIGH PLAINS WHICH WILL SCOUR OUT THE COLDER
AIR AND BRING A SHORT PERIOD OF WARMING TO THE CWA FOR MONDAY.
MOISTURE FROM THE SOUTHWEST SHOULD GET CAUGHT UP IN THE SWLY FLOW
AHEAD OF THE UPPER TROF AND ADVECT OVER THE CWA MONDAY NIGHT AND
TUESDAY. THE NEXT SURGE OF COLD AIR WILL THEN DROP SOUTH OVER THE
HIGH PLAINS EARLY TUESDAY AND WILL AID IN THE DEVELOPMENT OF SNOW
OVER THE REGION TUESDAY INTO TUESDAY NIGHT. QUITE COLD AGAIN WEDS
WITH SNOW ENDING EARLY AS THE SURFACE HIGH SETTLES ACROSS WY AND
THE MAIN UPPER TROF AXIS PASSES ACROSS LEAVING A NW FLOW ALOFT
OVER THE REGION. MAINLY DRY THURSDAY WITH WARMER TEMPS AGAIN AS
DOWNSLOPE FLOW RETURNS.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 506 PM MST THU FEB 26 2015

ATTENTION MAINLY ON KCYS AND KLAR TONIGHT AS A WEAK FRONT MOVES
INTO NORTHWESTERN COLORADO. EASTERLY UPSLOPING WINDS EAST OF THE
LARAMIE RANGE SHOULD KEEP KCYS IN IFR/LIFR CONDITIONS...WHILE THE
NORTHEASTERN EDGE OF SNOW WITH THE FRONT COULD IMPACT KLAR. WILL
CONTINUE TO MONITOR...BUT DO BELIEVE KCYS COULD STAY DOWN ALL DAY
FRIDAY WITH SOUTHEAST UPSLOPE WINDS.

&&

.FIRE WEATHER...
ISSUED AT 318 PM MST THU FEB 26 2015

COLD TEMPERATURES AND UNSETTLED CONDITIONS WILL SUPPRESS ANY FIRE
WEATHER CONCERNS FOR THE FORESEEABLE FUTURE.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 3 AM MST FRIDAY FOR WYZ117-118.

NE...NONE.
&&

$$

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



000
FXUS65 KCYS 262218
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
318 PM MST THU FEB 26 2015

.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 318 PM MST THU FEB 26 2015

ONGOING UPSLOPE SNOW EVENT IS THE MAIN CONCERN INITIALLY.
VISIBILITIES HAVE BEEN THE LOWEST AND SNOWFALL RATES THE HIGHEST
AT CHEYENNE REALLY ALL DAY LONG. THIS AS LLVL EASTERLY UPSLOPE
FLOW INTERACTS WITH THE FAVORABLE LEADING EDGE OF SHORTWAVE ENERGY
DIVING SOUTHEAST INTO THE HIGH PLAINS/FRONT RANGE. 12/18Z MODELS
SHOW LLVL LIFT INCREASING ACROSS LARAMIE COUNTY THRU THE REST OF
THE EVENING HOURS. MODELS HAVE CONTINUED TO TREND SNOWFALL AMOUNTS
UP ACROSS CENTRAL/SOUTHERN LARAMIE COUNTY ESPECIALLY FOR THIS
EVENING. SO IN AN EARLIER UPDATE...OPTED TO ISSUE A WINTER WEATHER
ADVISORY FOR CENTRAL LARAMIE COUNTY INCLUDING WRN FOOTHILLS
LOCATIONS EFFECTIVE THRU 10Z FRIDAY. EXPECT GENERALLY 2 TO 4
INCHES TO FALL...WITH THE HIGHEST AMOUNTS IN AREAS NEAREST THE
CHEYENNE RIDGE. LIFT/SNOW WILL DIMINISH SIGNIFICANTLY WITH THE
PASSAGE OF THE MID-LEVEL/H5 TROUGH FRIDAY 09-12Z. AMOUNTS WILL BE
SIGNIFICANTLY LIGHTER OUTSIDE OF LARAMIE COUNTY WITH THIS
SYSTEM...WITH PERHAPS AN INCH OR SO AT LARAMIE... WHEATLAND AND
KIMBALL. RAWLINS AND LOCATIONS TO THE NORTH OF THE NORTH PLATTE
RIVER VALLEY WILL SEE NOTHING AT ALL OR JUST SOME FLURRIES.
FORTUNATELY WINDS ARE ONLY PROGD TO BE AROUND 10 KNOTS...SO DONT
EXPECT BLOWING SNOW TO BE A CONCERN. ANOTHER COLD NIGHT AHEAD WITH
LOWS FALLING INTO THE SINGLE DIGITS OR SINGLE DIGITS BELOW ZERO.

QUICK SHORTWAVE RIDGE AXIS WILL USHER IN A MOSTLY DRY DAY FOR
FRIDAY WITH PERHAPS A FEW DEGREES OF WARMING BENEATH A VERY BRIEF
LLVL THERMAL RIDGING. EVEN SO HIGHS ON FRIDAY WILL ONLY REACH THE
TEENS AND 20S.

THE NEXT COLD FRONT WILL SLIDE FROM NORTH TO SOUTH DURING THE DAY
ON SATURDAY AS THE PATTERN FLATTENS AHEAD OF THE FORMING CUT-OFF
OVR THE GREAT BASIN. MOISTURE WILL BE LIMITED INITIALLY ON
SATURDAY AWAITING THE ARRIVAL OF AN EJECTING SHORTWAVE ENERGY AND
RESULTANT FAVORABLE ISENTROPIC LIFT/OVERRUNNING SET-UP. SNOW WILL
OVERSPREAD MUCH OF THE SOUTHERN TIER OF COUNTIES LATE SATURDAY AND
ESPECIALLY SATURDAY NIGHT. ALTHOUGH EXPECT THE BULK OF THE BEST
LIFT TO REMAIN SOUTH OVER COLORADO...SHOULD SEE SOME AT LEAST
LIGHT ACCUMULATIONS ESPECIALLY ALONG THE I80 CORRIDOR.

.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 318 PM MST THU FEB 26 2015

A RATHER COLD PATTERN EXPECTED TO PERSIST OVER THE REGION FOR MOST
OF THIS PERIOD WITH MONDAY LIKELY BEING THE MILDEST DAY THIS
PERIOD. INITIALLY THE CWA WILL BE UNDER CONFLUENT UPPER FLOW
BETWEEN ONE STREAM EMANATING FROM WESTERN CANADA INTO THE
NORTHERN PLAINS AND THE OTHER FROM THE SOUTHWEST CONUS AHEAD OF AN
UPPER LOW OFF THE CAL COAST. STILL CHILLY ACROSS THE AREA SUNDAY
AS A COLD SFC HIGH OVER THE HIGH PLAINS SHIFTS EAST DURING THE
DAY. A SHORTWAVE WILL MOVE INTO THE PACIFIC NW ON MONDAY AND PHASE
WITH THE CALIFORNIA UPPER LOW CREATING A LARGER SCALE UPPER TROF
OVER THE WESTERN CONUS MONDAY NIGHT. AT THE SAME TIME LEE TROFFING
WILL DEVELOP OVER THE HIGH PLAINS WHICH WILL SCOUR OUT THE COLDER
AIR AND BRING A SHORT PERIOD OF WARMING TO THE CWA FOR MONDAY.
MOISTURE FROM THE SOUTHWEST SHOULD GET CAUGHT UP IN THE SWLY FLOW
AHEAD OF THE UPPER TROF AND ADVECT OVER THE CWA MONDAY NIGHT AND
TUESDAY. THE NEXT SURGE OF COLD AIR WILL THEN DROP SOUTH OVER THE
HIGH PLAINS EARLY TUESDAY AND WILL AID IN THE DEVELOPMENT OF SNOW
OVER THE REGION TUESDAY INTO TUESDAY NIGHT. QUITE COLD AGAIN WEDS
WITH SNOW ENDING EARLY AS THE SURFACE HIGH SETTLES ACROSS WY AND
THE MAIN UPPER TROF AXIS PASSES ACROSS LEAVING A NW FLOW ALOFT
OVER THE REGION. MAINLY DRY THURSDAY WITH WARMER TEMPS AGAIN AS
DOWNSLOPE FLOW RETURNS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY MORNING)
ISSUED AT 1025 AM MST THU FEB 26 2015

MVFR/IFR CIGS AND VSBYS WILL AFFECT PARTS OF THE AREA...PRIMARILY
FAR SE WY AND SOUTHERN NEBRASKA TERMINALS...THROUGH THIS EVENING
BEFORE IMPROVING SLOWLY OVERNIGHT INTO FRIDAY MORNING.  AREAS OF
LIGHT SNOW WILL PERSIST OVER SE WY THROUGH THIS EVENING MAINLY
AFFECTING KCYS AND KLAR.

&&

.FIRE WEATHER...
ISSUED AT 318 PM MST THU FEB 26 2015

COLD TEMPERATURES AND UNSETTLED CONDITIONS WILL SUPPRESS ANY FIRE
WEATHER CONCERNS FOR THE FORESEEABLE FUTURE.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 3 AM MST FRIDAY FOR WYZ117-118.

NE...NONE.

&&

$$

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



000
FXUS65 KRIW 262125
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
225 PM MST THU FEB 26 2015

.SHORT TERM...TONIGHT THROUGH FRIDAY

SURFACE HIGH BUILDS INTO CENTRAL HIGH PLAINS TONIGHT. CHALLENGE
FOR CENTRAL WYOMING WILL BE TIMING OF DECREASING CLOUD COVER. WEAK
LOW LEVEL UPSLOPE FLOW PERSISTS...BUT SURFACE FLOW TO TURN MORE
SOUTHERLY TONIGHT. BEST CONFIDENCE FOR CLEARING WILL BE OVER
NATRONA AND JOHNSON COUNTIES...TO NORTHERN SECTIONS OF FORECAST
AREA. REGARDLESS...IT WILL BE QUITE COLD TONIGHT INTO EARLY FRIDAY.

WEAK FLOW ALOFT SETS UP ON FRIDAY WITH UPPER LEVEL LOW DROPPING INTO
CALIFORNIA. AS A RESULT...LITTLE OR NO ENERGY OVER WYOMING WELL AHEAD
OF THIS TROUGH. COULD STILL SEE A FEW MOUNTAIN SNOW SHOWERS WITH
HEATING OF THE DAY. OTHERWISE...ANOTHER COLD DAY ACROSS WEST
CENTRAL WYOMING WITH MORE SUNSHINE EXPECTED. WITH A VERY LIGHT
SURFACE WIND...IT SHOULD FEEL DECENT OUTDOORS ON FRIDAY.

.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY

AT THIS TIME...FRIDAY NIGHT LOOKS LIKE A MAINLY QUIET PERIOD WITH
JUST A FEW OROGRAPHIC SNOW SHOWERS ACROSS THE WESTERN MOUNTAINS. THE
REST OF THE REGION LOOKS MAINLY DRY WITH BELOW NORMAL TEMPERATURES
FOR THE START OF THE WEEKEND.

THE FIRST OF TWO SYSTEMS OF CONCERN IN THE LONG RANGE WILL START TO
EFFECT THE WEATHER FOR SATURDAY. A PIECE OF ENERGY WILL MOVE OFF A
CUT OFF LOW OVER CALIFORNIA AND MOVE INTO THE ROCKIES. HOWEVER...IT
APPEARS THAT THE BEST UPPER LEVEL SUPPORT WILL REMAIN OVER UTAH AND
COLORADO. AT AS RESULT...RIGHT NOW THIS LOOKS TO MAINLY A NUISANCE
EVENT AND ONLY EFFECT SOUTHERN PORTIONS OF THE COUNTY WARNING AREA
AND MAINLY WEST OF THE DIVIDE. BOTH THE GFS...EUROPEAN AND NAM ARE
IN GOOD AGREEMENT OF THIS. AS A RESULT...WE TRIMMED POPS ACROSS
AREAS NORTH AND EAST OF THE WIND RIVER RANGE FOR SATURDAY AND
SATURDAY NIGHT. EVEN IN AREAS THAT GET SNOW...THIS DOES NOT LOOK
WORTHY OF ANY SORT OF WARNINGS OR ADVISORIES RIGHT NOW. ON
SUNDAY...THERE IS SOME SLIGHT DISAGREEMENT WITH THE GFS KEEPING A
FEW SHOWERS ALONG THE SOUTHERN BORDER AND THE EUROPEAN MAINLY DRY.
WITH THE DIFFERENCES WE MADE FEW CHANGES TO CONTINUITY. MAINLY DRY
BUT CONTINUED CHILLY WEATHER WILL BE THE RULE FOR MONDAY WITH WEAK
SURFACE HIGH PRESSURE IN CONTROL.

THE NEXT AND PROBABLY MORE IMPACTFUL SYSTEM THEN APPROACHES FOR
MONDAY NIGHT AND ESPECIALLY FOR TUESDAY. THIS ONE HAS CHILLY ORIGINS
COMING IN FROM ALASKA.  THE MODELS AGAIN ARE IN FAIRLY GOOD
AGREEMENT WITH SNOW BEGINNING IN THE WEST ON MONDAY NIGHT AND THEN
SPREADING ACROSS ALL AREAS FOR TUESDAY. THE PREVIOUS FORECAST HAD
CHANCE POPS ACROSS MOST AREAS AND THESE LOOK PRETTY GOOD AT THIS
POINT SO FEW CHANGES WERE MADE. SNOWFALL AMOUNTS ARE STILL UNCERTAIN
RIGHT NOW...AS A LOT WILL DEPEND ON THE JET DYNAMICS AND OF COURSE
THE MODELS ARE PERFECT WITH THIS FIVE DAYS OUT...NOTE SARCASM. THERE
IS ALSO MORE AGREEMENT WITH THE END TIME. THE EUROPEAN HAS COME
AROUND TO THE MORE PROGRESSIVE GFS SOLUTION IN KICKING THE SYSTEM TO
THE SOUTH AND EAST DURING WEDNESDAY WITH ALL AREAS DRY AT THAT
POINT. TUESDAY NIGHT AND WEDNESDAY HAVE THE POTENTIAL TO QUITE COLD.
LOWS TUESDAY NIGHT MAY DEPEND ON HOW QUICKLY THE SKY CLEARS THOUGH.
MAINLY DRY BUT COOL WEATHER WILL BE THE RULE FOR WEDNESDAY INTO
THURSDAY WITH DRY NORTHWEST FLOW PREDOMINATING.

&&

.AVIATION.../00Z ISSUANCE/

CONDITIONS TO BECOME VFR TONIGHT AT ALL AIRPORT LOCATIONS. THIS IS
DUE TO DECREASING CLOUDS EAST OF THE CONTINENTAL DIVIDE. KBYG TO KCPR
EXPECTED TO CLEAR OUT BY LATE EVENING...THEN CENTRAL AND SOUTHWEST
WYOMING TO FOLLOW. HIGH PRESSURE IN CONTROL MOST AREAS ON FRIDAY.

SOME MOUNTAIN FLURRIES OR SNOW SHOWERS ARE STILL POSSIBLE FRIDAY
AFTERNOON AND EVENING. WESTERN MOUNTAIN PEAKS COULD BE OBSCURED
FRIDAY NIGHT INTO EARLY SATURDAY. OTHERWISE...LIGHT SURFACE WIND
AND VFR CONDITIONS CAN BE EXPECTED TO BEGIN THE WEEKEND ON BOTH
SIDES OF THE DIVIDE.

&&

.FIRE WEATHER...

NO FIRE WEATHER CONCERNS IN THE SHORT TERM...AS A COLD WEATHER
PATTERN CONTINUES FOR THE ENTIRE DISTRICT. LITTLE OR NO
PRECIPITATON THROUGH THE UPCOMING WEEKEND EAST OF THE DIVIDE...
BUT RELATIVE HUMIDITIES TO REMAIN HIGH.

WEST OF THE DIVIDE...INCREASING CLOUDS CAN BE EXPECTED ON FRIDAY.
A WEAK UPPER LEVEL TROUGH WILL MOVE OVER THE WESTERN MOUNTAINS LATE
FRIDAY TO HELP INITIATE SNOW SHOWERS. AREAS OF LIGHT SNOW WILL
PERSIST FRIDAY NIGHT...POSSIBLY REACHING THE WESTERN VALLEYS OF
WYOMING.

&&


.RIW WATCHES/WARNINGS/ADVISORIES...NONE.
&&

$$

SHORT TERM...KPL
LONG TERM...HATTINGS
AVIATION...KPL
FIRE WEATHER...KPL




000
FXUS65 KRIW 262125
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
225 PM MST THU FEB 26 2015

.SHORT TERM...TONIGHT THROUGH FRIDAY

SURFACE HIGH BUILDS INTO CENTRAL HIGH PLAINS TONIGHT. CHALLENGE
FOR CENTRAL WYOMING WILL BE TIMING OF DECREASING CLOUD COVER. WEAK
LOW LEVEL UPSLOPE FLOW PERSISTS...BUT SURFACE FLOW TO TURN MORE
SOUTHERLY TONIGHT. BEST CONFIDENCE FOR CLEARING WILL BE OVER
NATRONA AND JOHNSON COUNTIES...TO NORTHERN SECTIONS OF FORECAST
AREA. REGARDLESS...IT WILL BE QUITE COLD TONIGHT INTO EARLY FRIDAY.

WEAK FLOW ALOFT SETS UP ON FRIDAY WITH UPPER LEVEL LOW DROPPING INTO
CALIFORNIA. AS A RESULT...LITTLE OR NO ENERGY OVER WYOMING WELL AHEAD
OF THIS TROUGH. COULD STILL SEE A FEW MOUNTAIN SNOW SHOWERS WITH
HEATING OF THE DAY. OTHERWISE...ANOTHER COLD DAY ACROSS WEST
CENTRAL WYOMING WITH MORE SUNSHINE EXPECTED. WITH A VERY LIGHT
SURFACE WIND...IT SHOULD FEEL DECENT OUTDOORS ON FRIDAY.

.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY

AT THIS TIME...FRIDAY NIGHT LOOKS LIKE A MAINLY QUIET PERIOD WITH
JUST A FEW OROGRAPHIC SNOW SHOWERS ACROSS THE WESTERN MOUNTAINS. THE
REST OF THE REGION LOOKS MAINLY DRY WITH BELOW NORMAL TEMPERATURES
FOR THE START OF THE WEEKEND.

THE FIRST OF TWO SYSTEMS OF CONCERN IN THE LONG RANGE WILL START TO
EFFECT THE WEATHER FOR SATURDAY. A PIECE OF ENERGY WILL MOVE OFF A
CUT OFF LOW OVER CALIFORNIA AND MOVE INTO THE ROCKIES. HOWEVER...IT
APPEARS THAT THE BEST UPPER LEVEL SUPPORT WILL REMAIN OVER UTAH AND
COLORADO. AT AS RESULT...RIGHT NOW THIS LOOKS TO MAINLY A NUISANCE
EVENT AND ONLY EFFECT SOUTHERN PORTIONS OF THE COUNTY WARNING AREA
AND MAINLY WEST OF THE DIVIDE. BOTH THE GFS...EUROPEAN AND NAM ARE
IN GOOD AGREEMENT OF THIS. AS A RESULT...WE TRIMMED POPS ACROSS
AREAS NORTH AND EAST OF THE WIND RIVER RANGE FOR SATURDAY AND
SATURDAY NIGHT. EVEN IN AREAS THAT GET SNOW...THIS DOES NOT LOOK
WORTHY OF ANY SORT OF WARNINGS OR ADVISORIES RIGHT NOW. ON
SUNDAY...THERE IS SOME SLIGHT DISAGREEMENT WITH THE GFS KEEPING A
FEW SHOWERS ALONG THE SOUTHERN BORDER AND THE EUROPEAN MAINLY DRY.
WITH THE DIFFERENCES WE MADE FEW CHANGES TO CONTINUITY. MAINLY DRY
BUT CONTINUED CHILLY WEATHER WILL BE THE RULE FOR MONDAY WITH WEAK
SURFACE HIGH PRESSURE IN CONTROL.

THE NEXT AND PROBABLY MORE IMPACTFUL SYSTEM THEN APPROACHES FOR
MONDAY NIGHT AND ESPECIALLY FOR TUESDAY. THIS ONE HAS CHILLY ORIGINS
COMING IN FROM ALASKA.  THE MODELS AGAIN ARE IN FAIRLY GOOD
AGREEMENT WITH SNOW BEGINNING IN THE WEST ON MONDAY NIGHT AND THEN
SPREADING ACROSS ALL AREAS FOR TUESDAY. THE PREVIOUS FORECAST HAD
CHANCE POPS ACROSS MOST AREAS AND THESE LOOK PRETTY GOOD AT THIS
POINT SO FEW CHANGES WERE MADE. SNOWFALL AMOUNTS ARE STILL UNCERTAIN
RIGHT NOW...AS A LOT WILL DEPEND ON THE JET DYNAMICS AND OF COURSE
THE MODELS ARE PERFECT WITH THIS FIVE DAYS OUT...NOTE SARCASM. THERE
IS ALSO MORE AGREEMENT WITH THE END TIME. THE EUROPEAN HAS COME
AROUND TO THE MORE PROGRESSIVE GFS SOLUTION IN KICKING THE SYSTEM TO
THE SOUTH AND EAST DURING WEDNESDAY WITH ALL AREAS DRY AT THAT
POINT. TUESDAY NIGHT AND WEDNESDAY HAVE THE POTENTIAL TO QUITE COLD.
LOWS TUESDAY NIGHT MAY DEPEND ON HOW QUICKLY THE SKY CLEARS THOUGH.
MAINLY DRY BUT COOL WEATHER WILL BE THE RULE FOR WEDNESDAY INTO
THURSDAY WITH DRY NORTHWEST FLOW PREDOMINATING.

&&

.AVIATION.../00Z ISSUANCE/

CONDITIONS TO BECOME VFR TONIGHT AT ALL AIRPORT LOCATIONS. THIS IS
DUE TO DECREASING CLOUDS EAST OF THE CONTINENTAL DIVIDE. KBYG TO KCPR
EXPECTED TO CLEAR OUT BY LATE EVENING...THEN CENTRAL AND SOUTHWEST
WYOMING TO FOLLOW. HIGH PRESSURE IN CONTROL MOST AREAS ON FRIDAY.

SOME MOUNTAIN FLURRIES OR SNOW SHOWERS ARE STILL POSSIBLE FRIDAY
AFTERNOON AND EVENING. WESTERN MOUNTAIN PEAKS COULD BE OBSCURED
FRIDAY NIGHT INTO EARLY SATURDAY. OTHERWISE...LIGHT SURFACE WIND
AND VFR CONDITIONS CAN BE EXPECTED TO BEGIN THE WEEKEND ON BOTH
SIDES OF THE DIVIDE.

&&

.FIRE WEATHER...

NO FIRE WEATHER CONCERNS IN THE SHORT TERM...AS A COLD WEATHER
PATTERN CONTINUES FOR THE ENTIRE DISTRICT. LITTLE OR NO
PRECIPITATON THROUGH THE UPCOMING WEEKEND EAST OF THE DIVIDE...
BUT RELATIVE HUMIDITIES TO REMAIN HIGH.

WEST OF THE DIVIDE...INCREASING CLOUDS CAN BE EXPECTED ON FRIDAY.
A WEAK UPPER LEVEL TROUGH WILL MOVE OVER THE WESTERN MOUNTAINS LATE
FRIDAY TO HELP INITIATE SNOW SHOWERS. AREAS OF LIGHT SNOW WILL
PERSIST FRIDAY NIGHT...POSSIBLY REACHING THE WESTERN VALLEYS OF
WYOMING.

&&


.RIW WATCHES/WARNINGS/ADVISORIES...NONE.
&&

$$

SHORT TERM...KPL
LONG TERM...HATTINGS
AVIATION...KPL
FIRE WEATHER...KPL





000
FXUS63 KUNR 262108
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
208 PM MST THU FEB 26 2015

.SHORT TERM...THIS EVENING THROUGH FRIDAY NIGHT
ISSUED AT 207 PM MST THU FEB 26 2015

BROAD UPPER TROUGH REMAINS ACROSS MUCH OF THE CONUS...WITH NW FLOW
CONTINUING ACROSS THE REGION. ARCTIC HIGH PRESSURE SITS ACROSS THE
NRN PLAINS WITH MUCH COLDER TEMPS ACROSS THE DAKOTAS. HIGHS ACROSS
THE CWA SO FAR TODAY HAVE REACHED THE SINGLE DIGITS TO LOWER TEENS.
NW WINDS ACROSS THE WRN SD PLAINS ARE GENERALLY BLOWING AT 10 TO 15
MPH...WHILE LIGHTER OVER NE WY. RADAR SHOWING LIGHT SHSN ACROSS THE
BLACK HILLS PORTIONS OF CUSTER COUNTY.

SHSN WILL END TONIGHT AS SKIES CONTINUE TO CLEAR AREAWIDE. LOWS WILL
DROP TO ZERO TO 10 BELOW. SURFACE HIGH PRESSURE WILL SLIDE JUST EAST
OF THE AREA SETTING UP RETURN FLOW OVER THE CWA TONIGHT INTO FRIDAY.
SE WINDS WILL INCREASE THROUGH THE NIGHT PARTICULARLY OVER THE NE WY
PLAINS MAINLY AFTER 06Z. THESE WINDS WILL ALSO HELP RAISE TEMPS
SLIGHTLY. WIND CHILLS OF 10 BELOW TO 20 BELOW ZERO ARE EXPECTED
EARLY FRI MORNING.

OTHER THAN SOME PASSING CLOUDS ACROSS SW/SCNTRL SD...MOSTLY SUNNY
SKIES ARE EXPECTED FRIDAY. RETURN FLOW PRESSURE GRADIENT WILL
INCREASE THROUGH THE DAY WITH SE WINDS INCREASING TO 10 TO 20 MPH
OVER THE WRN SD PLAINS...AND CONTINUING OVER THE NE WY PLAINS. HIGHS
WILL BE WARMER...BUT STILL BELOW SEASONAL AVERAGES...REACHING THE
20S TO LOWER 30S OVER MOST LOCATIONS.

.LONG TERM...SATURDAY THROUGH THURSDAY
ISSUED AT 207 PM MST THU FEB 26 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND AS AN UPPER TROUGH AND SURFACE HIGH REMAINS ACROSS THE
REGION. THE SURFACE HIGH WILL MOVE EAST MONDAY AS THE UPPER FLOW
BECOMES MORE WESTERLY AND WARMER PACIFIC SOURCED AIR PUSHES INTO
THE NORTHERN PLAINS. THE MODELS STILL AGREE ON A BRIEF WARMUP
MONDAY. A LARGE STORM SYSTEM WILL DEVELOPS ACROSS THE CNTRL
PORTIONS OF THE CONUS TUESDAY. ARCTIC AIR WILL BE DRAWN IN BEHIND
THE STORM OVER THE REGION. HAVE LOWERED TUESDAY HIGHS SOME MORE
OVER NE WY AND NW SD. THE TROUGH AXIS CROSSING THE REGION WILL
ALSO BRING A CHANCE OF SNOW TO MUCH OF THE AREA TUE/TUE NIGHT.
WARMER AND DRIER WEATHER IS EXPECTED FOR THE SECOND HALF OF THE
WEEK AS A STRONG UPPER RIDGE BEGINS BUILDING IN FROM THE WEST.

&&

.AVIATION...FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING
ISSUED AT 207 PM MST THU FEB 26 2015

MVFR CIGS ACROSS THE SRN BLKHLS ASSOCIATED WITH -SHSN WILL
DISSIPATE EARLY THIS EVENING...WITH CONDITIONS BECOMING VFR. VFR
EXPECTED ELSEWHERE.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...13
LONG TERM...13
AVIATION...7






000
FXUS63 KUNR 261755
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1055 AM MST THU FEB 26 2015

.UPDATE...
ISSUED AT 1050 AM MST THU FEB 26 2015

ONLY A COUPLE OF SMALL UPDATES TO THE FORECAST THIS MORNING. HAVE
ADJUSTED FORECAST HIGHS DOWN A FEW DEGREES FOR MOST LOCATIONS AS
THE MODELS ARE STRUGGLING TO CAPTURE THE ARCTIC AIRMASS OVER THE
AREA. ALSO UPPED POPS AND SKY COVER OVER NORTHEASTERN WY AS LOW
CLOUDS AND LIGHT SNOW SHOWERS ARE LINGERING OVER THAT AREA A BIT
LONGER THAN EXPECTED. MOST OF THAT ACTIVITY SHOULD DIE DOWN OVER THE
NEXT SEVERAL HOURS.

&&

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
ISSUED AT 305 AM MST THU FEB 26 2015

CURRENT SURFACE ANALYSIS SHOWS ARCTIC HIGH PRESSURE CENTERED OVER
SOUTHERN SK...MOVING SOUTHEASTWARD TOWARD THE DAKOTAS. UPPER LEVEL
ANALYSIS SHOWS LOW NEAR HUDSON BAY...WITH LARGE SCALE TROF
COVERING MUCH OF NORTH AMERICA AT THE MOMENT. PERSISTENT NORTHWEST
FLOW IS IN PLACE OVER THE NORTHERN PLAINS. SKIES ARE STILL MOSTLY
CLOUDY ACROSS MUCH OF THE CWA...WITH SOME CLEARING OVER NORTHWEST
SD. THIS CLEARING WILL SLOWLY MOVE SOUTH AND WEST ACROSS THE CWA
THIS MORNING. KUDX RADAR STILL SHOWS SOME FLURRIES ACROSS THE
BLACK HILLS AND SOUTHWEST SD...BUT THE DRYING TREND WILL CONTINUE
TO MOVE SOUTHWESTWARD EARLY THIS MORNING. TEMPS RANGE FROM AROUND
5 BELOW OVER FAR NORTHWESTERN SD...WHERE SKIES HAVE CLEARED
OUT...TO NEAR 10 ABOVE ACROSS FAR SOUTHWEST SD. WINDS ARE MOSTLY
FROM THE NORTH AT 5 TO 10 MPH...HELPING TO PRODUCE WIND CHILLS TO
AROUND 20 BELOW ZERO ACROSS NORTHWEST SD.

COLD...BUT MAINLY DRY WEATHER...CAN BE EXPECTED FOR THE REST OF THE
WEEK AS THE ARCTIC HIGH TO THE NORTH SLIDES SOUTHEAST ACROSS THE
DAKOTAS TODAY AND TONIGHT. SHORT RANGE MODELS ARE IN GOOD AGREEMENT
FOR THE NEXT COUPLE OF DAYS. HIGHS TODAY WILL BE IN THE TEENS...WITH
WIND CHILLS STAYING BELOW ZERO THROUGH MUCH OF THE MORNING. SKIES
WILL CONTINUE TO GRADUALLY CLEAR FROM NORTHEAST TO SOUTHWEST
TODAY...WITH MAINLY SUNNY SKIES IN MOST AREAS BY THE AFTERNOON. WILL
KEEP A SLIGHT CHANCE FOR LIGHT SNOW/FLURRIES ACROSS SOUTHWESTERN
PORTIONS OF NORTHEAST WY...AS WELL AS FAR SOUTHWEST SD...EARLY THIS
MORNING. WILL ALSO KEEP LOW POPS FOR SNOW SHOWERS THIS AFTERNOON
ACROSS THE CENTRAL AND SOUTHERN BLACK HILLS...WHERE STEEP LAPSE
RATES AND SUFFICIENT MOISTURE COULD ALLOW A FEW SHOWERS TO DEVELOP.

BITTER COLD TONIGHT AS HIGH SLIDES SOUTHEAST OF THE REGION AND SKIES
REMAIN MOSTLY CLEAR. LOWS WILL GENERALLY RANGE FROM NEAR 10 BELOW IN
NORTHWEST SD AND THE USUAL COLD SPOTS ELSEWHERE...TO NEAR OR SLIGHT
ABOVE ZERO ACROSS PORTIONS OF NORTHEAST WY WHERE SOUTHERLY WINDS
WILL INCREASE OVERNIGHT.

SOUTH TO SOUTHEAST WINDS WILL INCREASE EVERYWHERE ON FRIDAY AND
BECOME BREEZY ACROSS MUCH OF THE PLAINS BY THE AFTERNOON. MILDER AIR
PUSHING INTO THE AREA WILL ALLOW MOST LOCATIONS TO SEE HIGHS IN THE
20S...WITH SOME SPOTS TO THE SOUTH AND EAST OF THE HILLS NEAR 30.
SKIES WILL BE MOSTLY SUNNY...WITH SOME INCREASE IN CLOUDS FRIDAY
NIGHT OVER SOUTHERN AND WESTERN AREAS AS A STRONG SHORTWAVE DIGS
SOUTHEASTWARD ACROSS THE PACIFIC NW AND GREAT BASIN REGIONS.

.LONG TERM...SATURDAY THROUGH WEDNESDAY
ISSUED AT 305 AM MST THU FEB 26 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND AS A COLD SFC HIGH SETTLES OVER THE AREA. THERE IS A
SLIGHT CHANCE OF VERY LIGHT SNOW OR FLURRIES IN THE BAROCLINIC
ZONE ALONG THE WESTERN EDGE OF THE HIGH OVER NORTHEASTERN
WYOMING...THE BLACK HILLS AND FAR SOUTHWESTERN SOUTH DAKOTA ON
SATURDAY AND SATURDAY NIGHT. DRY WEATHER IS EXPECTED ON SUNDAY.
THE SURFACE HIGH WILL MOVE OFF TO THE EAST ON MONDAY AS THE UPPER
FLOW BECOMES MORE WESTERLY AND WARMER PACIFIC SOURCED AIR PUSHES
INTO THE NORTHERN PLAINS. THE MODELS STILL AGREE ON A BRIEF WARMUP
MONDAY. THE LATEST RUN OF THE ECMWF IS NOW COMING MORE IN LINE
WITH THE GFS IN SWINGING THE NEXT COLD FRONT ACROSS THE AREA ON
TUESDAY...ALTHOUGH THE ECMWF TIMING OF THE FRONT STILL LAGS BEHIND
THE GFS BY AROUND 6 HOURS. HAVE LOWERED TUESDAY HIGHS OVER NERN
WYOMING TO COME MORE IN LINE WITH THE EARLIER FRONTAL PASSAGE.
LOOKS LIKE A CHANCE OF SNOW OVER NERN WY AND FAR WRN SD ON
TUES/TUES NIGHT AS COLDER AIR FLOWS IN BEHIND THE FRONT. THERE IS
A SLIGHT CHANCE OF SNOW OVER SOUTHWESTERN AND SOUTH CENTRAL SOUTH
DAKOTA ON WEDNESDAY AS THOSE AREAS WILL BE ON THE NORTHERN EDGE OF
A BAND OF SNOW ASSOCIATED WITH ISENTROPIC LIFT AHEAD OF AN UPPER
TROUGH MOVING INTO THE CENTRAL PLAINS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY)
ISSUED AT 1034 AM MST THU FEB 26 2015

MVFR CIGS WILL PERSIST ACROSS NORTHEAST WYOMING INTO SOUTHWEST
SOUTH DAKOTA THIS AFTERNOON...WITH CONDITIONS BECOMING VFR THIS
EVENING. VFR ELSEWHERE.


&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

UPDATE...MCKEMY
SHORT TERM...26
LONG TERM...10
AVIATION...7







000
FXUS63 KUNR 261755
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1055 AM MST THU FEB 26 2015

.UPDATE...
ISSUED AT 1050 AM MST THU FEB 26 2015

ONLY A COUPLE OF SMALL UPDATES TO THE FORECAST THIS MORNING. HAVE
ADJUSTED FORECAST HIGHS DOWN A FEW DEGREES FOR MOST LOCATIONS AS
THE MODELS ARE STRUGGLING TO CAPTURE THE ARCTIC AIRMASS OVER THE
AREA. ALSO UPPED POPS AND SKY COVER OVER NORTHEASTERN WY AS LOW
CLOUDS AND LIGHT SNOW SHOWERS ARE LINGERING OVER THAT AREA A BIT
LONGER THAN EXPECTED. MOST OF THAT ACTIVITY SHOULD DIE DOWN OVER THE
NEXT SEVERAL HOURS.

&&

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
ISSUED AT 305 AM MST THU FEB 26 2015

CURRENT SURFACE ANALYSIS SHOWS ARCTIC HIGH PRESSURE CENTERED OVER
SOUTHERN SK...MOVING SOUTHEASTWARD TOWARD THE DAKOTAS. UPPER LEVEL
ANALYSIS SHOWS LOW NEAR HUDSON BAY...WITH LARGE SCALE TROF
COVERING MUCH OF NORTH AMERICA AT THE MOMENT. PERSISTENT NORTHWEST
FLOW IS IN PLACE OVER THE NORTHERN PLAINS. SKIES ARE STILL MOSTLY
CLOUDY ACROSS MUCH OF THE CWA...WITH SOME CLEARING OVER NORTHWEST
SD. THIS CLEARING WILL SLOWLY MOVE SOUTH AND WEST ACROSS THE CWA
THIS MORNING. KUDX RADAR STILL SHOWS SOME FLURRIES ACROSS THE
BLACK HILLS AND SOUTHWEST SD...BUT THE DRYING TREND WILL CONTINUE
TO MOVE SOUTHWESTWARD EARLY THIS MORNING. TEMPS RANGE FROM AROUND
5 BELOW OVER FAR NORTHWESTERN SD...WHERE SKIES HAVE CLEARED
OUT...TO NEAR 10 ABOVE ACROSS FAR SOUTHWEST SD. WINDS ARE MOSTLY
FROM THE NORTH AT 5 TO 10 MPH...HELPING TO PRODUCE WIND CHILLS TO
AROUND 20 BELOW ZERO ACROSS NORTHWEST SD.

COLD...BUT MAINLY DRY WEATHER...CAN BE EXPECTED FOR THE REST OF THE
WEEK AS THE ARCTIC HIGH TO THE NORTH SLIDES SOUTHEAST ACROSS THE
DAKOTAS TODAY AND TONIGHT. SHORT RANGE MODELS ARE IN GOOD AGREEMENT
FOR THE NEXT COUPLE OF DAYS. HIGHS TODAY WILL BE IN THE TEENS...WITH
WIND CHILLS STAYING BELOW ZERO THROUGH MUCH OF THE MORNING. SKIES
WILL CONTINUE TO GRADUALLY CLEAR FROM NORTHEAST TO SOUTHWEST
TODAY...WITH MAINLY SUNNY SKIES IN MOST AREAS BY THE AFTERNOON. WILL
KEEP A SLIGHT CHANCE FOR LIGHT SNOW/FLURRIES ACROSS SOUTHWESTERN
PORTIONS OF NORTHEAST WY...AS WELL AS FAR SOUTHWEST SD...EARLY THIS
MORNING. WILL ALSO KEEP LOW POPS FOR SNOW SHOWERS THIS AFTERNOON
ACROSS THE CENTRAL AND SOUTHERN BLACK HILLS...WHERE STEEP LAPSE
RATES AND SUFFICIENT MOISTURE COULD ALLOW A FEW SHOWERS TO DEVELOP.

BITTER COLD TONIGHT AS HIGH SLIDES SOUTHEAST OF THE REGION AND SKIES
REMAIN MOSTLY CLEAR. LOWS WILL GENERALLY RANGE FROM NEAR 10 BELOW IN
NORTHWEST SD AND THE USUAL COLD SPOTS ELSEWHERE...TO NEAR OR SLIGHT
ABOVE ZERO ACROSS PORTIONS OF NORTHEAST WY WHERE SOUTHERLY WINDS
WILL INCREASE OVERNIGHT.

SOUTH TO SOUTHEAST WINDS WILL INCREASE EVERYWHERE ON FRIDAY AND
BECOME BREEZY ACROSS MUCH OF THE PLAINS BY THE AFTERNOON. MILDER AIR
PUSHING INTO THE AREA WILL ALLOW MOST LOCATIONS TO SEE HIGHS IN THE
20S...WITH SOME SPOTS TO THE SOUTH AND EAST OF THE HILLS NEAR 30.
SKIES WILL BE MOSTLY SUNNY...WITH SOME INCREASE IN CLOUDS FRIDAY
NIGHT OVER SOUTHERN AND WESTERN AREAS AS A STRONG SHORTWAVE DIGS
SOUTHEASTWARD ACROSS THE PACIFIC NW AND GREAT BASIN REGIONS.

.LONG TERM...SATURDAY THROUGH WEDNESDAY
ISSUED AT 305 AM MST THU FEB 26 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND AS A COLD SFC HIGH SETTLES OVER THE AREA. THERE IS A
SLIGHT CHANCE OF VERY LIGHT SNOW OR FLURRIES IN THE BAROCLINIC
ZONE ALONG THE WESTERN EDGE OF THE HIGH OVER NORTHEASTERN
WYOMING...THE BLACK HILLS AND FAR SOUTHWESTERN SOUTH DAKOTA ON
SATURDAY AND SATURDAY NIGHT. DRY WEATHER IS EXPECTED ON SUNDAY.
THE SURFACE HIGH WILL MOVE OFF TO THE EAST ON MONDAY AS THE UPPER
FLOW BECOMES MORE WESTERLY AND WARMER PACIFIC SOURCED AIR PUSHES
INTO THE NORTHERN PLAINS. THE MODELS STILL AGREE ON A BRIEF WARMUP
MONDAY. THE LATEST RUN OF THE ECMWF IS NOW COMING MORE IN LINE
WITH THE GFS IN SWINGING THE NEXT COLD FRONT ACROSS THE AREA ON
TUESDAY...ALTHOUGH THE ECMWF TIMING OF THE FRONT STILL LAGS BEHIND
THE GFS BY AROUND 6 HOURS. HAVE LOWERED TUESDAY HIGHS OVER NERN
WYOMING TO COME MORE IN LINE WITH THE EARLIER FRONTAL PASSAGE.
LOOKS LIKE A CHANCE OF SNOW OVER NERN WY AND FAR WRN SD ON
TUES/TUES NIGHT AS COLDER AIR FLOWS IN BEHIND THE FRONT. THERE IS
A SLIGHT CHANCE OF SNOW OVER SOUTHWESTERN AND SOUTH CENTRAL SOUTH
DAKOTA ON WEDNESDAY AS THOSE AREAS WILL BE ON THE NORTHERN EDGE OF
A BAND OF SNOW ASSOCIATED WITH ISENTROPIC LIFT AHEAD OF AN UPPER
TROUGH MOVING INTO THE CENTRAL PLAINS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY)
ISSUED AT 1034 AM MST THU FEB 26 2015

MVFR CIGS WILL PERSIST ACROSS NORTHEAST WYOMING INTO SOUTHWEST
SOUTH DAKOTA THIS AFTERNOON...WITH CONDITIONS BECOMING VFR THIS
EVENING. VFR ELSEWHERE.


&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

UPDATE...MCKEMY
SHORT TERM...26
LONG TERM...10
AVIATION...7






000
FXUS63 KUNR 261755
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1055 AM MST THU FEB 26 2015

.UPDATE...
ISSUED AT 1050 AM MST THU FEB 26 2015

ONLY A COUPLE OF SMALL UPDATES TO THE FORECAST THIS MORNING. HAVE
ADJUSTED FORECAST HIGHS DOWN A FEW DEGREES FOR MOST LOCATIONS AS
THE MODELS ARE STRUGGLING TO CAPTURE THE ARCTIC AIRMASS OVER THE
AREA. ALSO UPPED POPS AND SKY COVER OVER NORTHEASTERN WY AS LOW
CLOUDS AND LIGHT SNOW SHOWERS ARE LINGERING OVER THAT AREA A BIT
LONGER THAN EXPECTED. MOST OF THAT ACTIVITY SHOULD DIE DOWN OVER THE
NEXT SEVERAL HOURS.

&&

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
ISSUED AT 305 AM MST THU FEB 26 2015

CURRENT SURFACE ANALYSIS SHOWS ARCTIC HIGH PRESSURE CENTERED OVER
SOUTHERN SK...MOVING SOUTHEASTWARD TOWARD THE DAKOTAS. UPPER LEVEL
ANALYSIS SHOWS LOW NEAR HUDSON BAY...WITH LARGE SCALE TROF
COVERING MUCH OF NORTH AMERICA AT THE MOMENT. PERSISTENT NORTHWEST
FLOW IS IN PLACE OVER THE NORTHERN PLAINS. SKIES ARE STILL MOSTLY
CLOUDY ACROSS MUCH OF THE CWA...WITH SOME CLEARING OVER NORTHWEST
SD. THIS CLEARING WILL SLOWLY MOVE SOUTH AND WEST ACROSS THE CWA
THIS MORNING. KUDX RADAR STILL SHOWS SOME FLURRIES ACROSS THE
BLACK HILLS AND SOUTHWEST SD...BUT THE DRYING TREND WILL CONTINUE
TO MOVE SOUTHWESTWARD EARLY THIS MORNING. TEMPS RANGE FROM AROUND
5 BELOW OVER FAR NORTHWESTERN SD...WHERE SKIES HAVE CLEARED
OUT...TO NEAR 10 ABOVE ACROSS FAR SOUTHWEST SD. WINDS ARE MOSTLY
FROM THE NORTH AT 5 TO 10 MPH...HELPING TO PRODUCE WIND CHILLS TO
AROUND 20 BELOW ZERO ACROSS NORTHWEST SD.

COLD...BUT MAINLY DRY WEATHER...CAN BE EXPECTED FOR THE REST OF THE
WEEK AS THE ARCTIC HIGH TO THE NORTH SLIDES SOUTHEAST ACROSS THE
DAKOTAS TODAY AND TONIGHT. SHORT RANGE MODELS ARE IN GOOD AGREEMENT
FOR THE NEXT COUPLE OF DAYS. HIGHS TODAY WILL BE IN THE TEENS...WITH
WIND CHILLS STAYING BELOW ZERO THROUGH MUCH OF THE MORNING. SKIES
WILL CONTINUE TO GRADUALLY CLEAR FROM NORTHEAST TO SOUTHWEST
TODAY...WITH MAINLY SUNNY SKIES IN MOST AREAS BY THE AFTERNOON. WILL
KEEP A SLIGHT CHANCE FOR LIGHT SNOW/FLURRIES ACROSS SOUTHWESTERN
PORTIONS OF NORTHEAST WY...AS WELL AS FAR SOUTHWEST SD...EARLY THIS
MORNING. WILL ALSO KEEP LOW POPS FOR SNOW SHOWERS THIS AFTERNOON
ACROSS THE CENTRAL AND SOUTHERN BLACK HILLS...WHERE STEEP LAPSE
RATES AND SUFFICIENT MOISTURE COULD ALLOW A FEW SHOWERS TO DEVELOP.

BITTER COLD TONIGHT AS HIGH SLIDES SOUTHEAST OF THE REGION AND SKIES
REMAIN MOSTLY CLEAR. LOWS WILL GENERALLY RANGE FROM NEAR 10 BELOW IN
NORTHWEST SD AND THE USUAL COLD SPOTS ELSEWHERE...TO NEAR OR SLIGHT
ABOVE ZERO ACROSS PORTIONS OF NORTHEAST WY WHERE SOUTHERLY WINDS
WILL INCREASE OVERNIGHT.

SOUTH TO SOUTHEAST WINDS WILL INCREASE EVERYWHERE ON FRIDAY AND
BECOME BREEZY ACROSS MUCH OF THE PLAINS BY THE AFTERNOON. MILDER AIR
PUSHING INTO THE AREA WILL ALLOW MOST LOCATIONS TO SEE HIGHS IN THE
20S...WITH SOME SPOTS TO THE SOUTH AND EAST OF THE HILLS NEAR 30.
SKIES WILL BE MOSTLY SUNNY...WITH SOME INCREASE IN CLOUDS FRIDAY
NIGHT OVER SOUTHERN AND WESTERN AREAS AS A STRONG SHORTWAVE DIGS
SOUTHEASTWARD ACROSS THE PACIFIC NW AND GREAT BASIN REGIONS.

.LONG TERM...SATURDAY THROUGH WEDNESDAY
ISSUED AT 305 AM MST THU FEB 26 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND AS A COLD SFC HIGH SETTLES OVER THE AREA. THERE IS A
SLIGHT CHANCE OF VERY LIGHT SNOW OR FLURRIES IN THE BAROCLINIC
ZONE ALONG THE WESTERN EDGE OF THE HIGH OVER NORTHEASTERN
WYOMING...THE BLACK HILLS AND FAR SOUTHWESTERN SOUTH DAKOTA ON
SATURDAY AND SATURDAY NIGHT. DRY WEATHER IS EXPECTED ON SUNDAY.
THE SURFACE HIGH WILL MOVE OFF TO THE EAST ON MONDAY AS THE UPPER
FLOW BECOMES MORE WESTERLY AND WARMER PACIFIC SOURCED AIR PUSHES
INTO THE NORTHERN PLAINS. THE MODELS STILL AGREE ON A BRIEF WARMUP
MONDAY. THE LATEST RUN OF THE ECMWF IS NOW COMING MORE IN LINE
WITH THE GFS IN SWINGING THE NEXT COLD FRONT ACROSS THE AREA ON
TUESDAY...ALTHOUGH THE ECMWF TIMING OF THE FRONT STILL LAGS BEHIND
THE GFS BY AROUND 6 HOURS. HAVE LOWERED TUESDAY HIGHS OVER NERN
WYOMING TO COME MORE IN LINE WITH THE EARLIER FRONTAL PASSAGE.
LOOKS LIKE A CHANCE OF SNOW OVER NERN WY AND FAR WRN SD ON
TUES/TUES NIGHT AS COLDER AIR FLOWS IN BEHIND THE FRONT. THERE IS
A SLIGHT CHANCE OF SNOW OVER SOUTHWESTERN AND SOUTH CENTRAL SOUTH
DAKOTA ON WEDNESDAY AS THOSE AREAS WILL BE ON THE NORTHERN EDGE OF
A BAND OF SNOW ASSOCIATED WITH ISENTROPIC LIFT AHEAD OF AN UPPER
TROUGH MOVING INTO THE CENTRAL PLAINS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY)
ISSUED AT 1034 AM MST THU FEB 26 2015

MVFR CIGS WILL PERSIST ACROSS NORTHEAST WYOMING INTO SOUTHWEST
SOUTH DAKOTA THIS AFTERNOON...WITH CONDITIONS BECOMING VFR THIS
EVENING. VFR ELSEWHERE.


&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

UPDATE...MCKEMY
SHORT TERM...26
LONG TERM...10
AVIATION...7







000
FXUS63 KUNR 261735
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1035 AM MST THU FEB 26 2015

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
ISSUED AT 305 AM MST THU FEB 26 2015

CURRENT SURFACE ANALYSIS SHOWS ARCTIC HIGH PRESSURE CENTERED OVER
SOUTHERN SK...MOVING SOUTHEASTWARD TOWARD THE DAKOTAS. UPPER LEVEL
ANALYSIS SHOWS LOW NEAR HUDSON BAY...WITH LARGE SCALE TROF
COVERING MUCH OF NORTH AMERICA AT THE MOMENT. PERSISTENT NORTHWEST
FLOW IS IN PLACE OVER THE NORTHERN PLAINS. SKIES ARE STILL MOSTLY
CLOUDY ACROSS MUCH OF THE CWA...WITH SOME CLEARING OVER NORTHWEST
SD. THIS CLEARING WILL SLOWLY MOVE SOUTH AND WEST ACROSS THE CWA
THIS MORNING. KUDX RADAR STILL SHOWS SOME FLURRIES ACROSS THE
BLACK HILLS AND SOUTHWEST SD...BUT THE DRYING TREND WILL CONTINUE
TO MOVE SOUTHWESTWARD EARLY THIS MORNING. TEMPS RANGE FROM AROUND
5 BELOW OVER FAR NORTHWESTERN SD...WHERE SKIES HAVE CLEARED
OUT...TO NEAR 10 ABOVE ACROSS FAR SOUTHWEST SD. WINDS ARE MOSTLY
FROM THE NORTH AT 5 TO 10 MPH...HELPING TO PRODUCE WIND CHILLS TO
AROUND 20 BELOW ZERO ACROSS NORTHWEST SD.

COLD...BUT MAINLY DRY WEATHER...CAN BE EXPECTED FOR THE REST OF THE
WEEK AS THE ARCTIC HIGH TO THE NORTH SLIDES SOUTHEAST ACROSS THE
DAKOTAS TODAY AND TONIGHT. SHORT RANGE MODELS ARE IN GOOD AGREEMENT
FOR THE NEXT COUPLE OF DAYS. HIGHS TODAY WILL BE IN THE TEENS...WITH
WIND CHILLS STAYING BELOW ZERO THROUGH MUCH OF THE MORNING. SKIES
WILL CONTINUE TO GRADUALLY CLEAR FROM NORTHEAST TO SOUTHWEST
TODAY...WITH MAINLY SUNNY SKIES IN MOST AREAS BY THE AFTERNOON. WILL
KEEP A SLIGHT CHANCE FOR LIGHT SNOW/FLURRIES ACROSS SOUTHWESTERN
PORTIONS OF NORTHEAST WY...AS WELL AS FAR SOUTHWEST SD...EARLY THIS
MORNING. WILL ALSO KEEP LOW POPS FOR SNOW SHOWERS THIS AFTERNOON
ACROSS THE CENTRAL AND SOUTHERN BLACK HILLS...WHERE STEEP LAPSE
RATES AND SUFFICIENT MOISTURE COULD ALLOW A FEW SHOWERS TO DEVELOP.

BITTER COLD TONIGHT AS HIGH SLIDES SOUTHEAST OF THE REGION AND SKIES
REMAIN MOSTLY CLEAR. LOWS WILL GENERALLY RANGE FROM NEAR 10 BELOW IN
NORTHWEST SD AND THE USUAL COLD SPOTS ELSEWHERE...TO NEAR OR SLIGHT
ABOVE ZERO ACROSS PORTIONS OF NORTHEAST WY WHERE SOUTHERLY WINDS
WILL INCREASE OVERNIGHT.

SOUTH TO SOUTHEAST WINDS WILL INCREASE EVERYWHERE ON FRIDAY AND
BECOME BREEZY ACROSS MUCH OF THE PLAINS BY THE AFTERNOON. MILDER AIR
PUSHING INTO THE AREA WILL ALLOW MOST LOCATIONS TO SEE HIGHS IN THE
20S...WITH SOME SPOTS TO THE SOUTH AND EAST OF THE HILLS NEAR 30.
SKIES WILL BE MOSTLY SUNNY...WITH SOME INCREASE IN CLOUDS FRIDAY
NIGHT OVER SOUTHERN AND WESTERN AREAS AS A STRONG SHORTWAVE DIGS
SOUTHEASTWARD ACROSS THE PACIFIC NW AND GREAT BASIN REGIONS.

.LONG TERM...SATURDAY THROUGH WEDNESDAY
ISSUED AT 305 AM MST THU FEB 26 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND AS A COLD SFC HIGH SETTLES OVER THE AREA. THERE IS A
SLIGHT CHANCE OF VERY LIGHT SNOW OR FLURRIES IN THE BAROCLINIC
ZONE ALONG THE WESTERN EDGE OF THE HIGH OVER NORTHEASTERN
WYOMING...THE BLACK HILLS AND FAR SOUTHWESTERN SOUTH DAKOTA ON
SATURDAY AND SATURDAY NIGHT. DRY WEATHER IS EXPECTED ON SUNDAY.
THE SURFACE HIGH WILL MOVE OFF TO THE EAST ON MONDAY AS THE UPPER
FLOW BECOMES MORE WESTERLY AND WARMER PACIFIC SOURCED AIR PUSHES
INTO THE NORTHERN PLAINS. THE MODELS STILL AGREE ON A BRIEF WARMUP
MONDAY. THE LATEST RUN OF THE ECMWF IS NOW COMING MORE IN LINE
WITH THE GFS IN SWINGING THE NEXT COLD FRONT ACROSS THE AREA ON
TUESDAY...ALTHOUGH THE ECMWF TIMING OF THE FRONT STILL LAGS BEHIND
THE GFS BY AROUND 6 HOURS. HAVE LOWERED TUESDAY HIGHS OVER NERN
WYOMING TO COME MORE IN LINE WITH THE EARLIER FRONTAL PASSAGE.
LOOKS LIKE A CHANCE OF SNOW OVER NERN WY AND FAR WRN SD ON
TUES/TUES NIGHT AS COLDER AIR FLOWS IN BEHIND THE FRONT. THERE IS
A SLIGHT CHANCE OF SNOW OVER SOUTHWESTERN AND SOUTH CENTRAL SOUTH
DAKOTA ON WEDNESDAY AS THOSE AREAS WILL BE ON THE NORTHERN EDGE OF
A BAND OF SNOW ASSOCIATED WITH ISENTROPIC LIFT AHEAD OF AN UPPER
TROUGH MOVING INTO THE CENTRAL PLAINS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY)
ISSUED AT 1034 AM MST THU FEB 26 2015

MVFR CIGS WILL PERSIST ACROSS NORTHEAST WYOMING INTO SOUTHWEST
SOUTH DAKOTA THIS AFTERNOON...WITH CONDITIONS BECOMING VFR THIS
EVENING. VFR ELSEWHERE.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...26
LONG TERM...10
AVIATION...7







000
FXUS63 KUNR 261735
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1035 AM MST THU FEB 26 2015

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
ISSUED AT 305 AM MST THU FEB 26 2015

CURRENT SURFACE ANALYSIS SHOWS ARCTIC HIGH PRESSURE CENTERED OVER
SOUTHERN SK...MOVING SOUTHEASTWARD TOWARD THE DAKOTAS. UPPER LEVEL
ANALYSIS SHOWS LOW NEAR HUDSON BAY...WITH LARGE SCALE TROF
COVERING MUCH OF NORTH AMERICA AT THE MOMENT. PERSISTENT NORTHWEST
FLOW IS IN PLACE OVER THE NORTHERN PLAINS. SKIES ARE STILL MOSTLY
CLOUDY ACROSS MUCH OF THE CWA...WITH SOME CLEARING OVER NORTHWEST
SD. THIS CLEARING WILL SLOWLY MOVE SOUTH AND WEST ACROSS THE CWA
THIS MORNING. KUDX RADAR STILL SHOWS SOME FLURRIES ACROSS THE
BLACK HILLS AND SOUTHWEST SD...BUT THE DRYING TREND WILL CONTINUE
TO MOVE SOUTHWESTWARD EARLY THIS MORNING. TEMPS RANGE FROM AROUND
5 BELOW OVER FAR NORTHWESTERN SD...WHERE SKIES HAVE CLEARED
OUT...TO NEAR 10 ABOVE ACROSS FAR SOUTHWEST SD. WINDS ARE MOSTLY
FROM THE NORTH AT 5 TO 10 MPH...HELPING TO PRODUCE WIND CHILLS TO
AROUND 20 BELOW ZERO ACROSS NORTHWEST SD.

COLD...BUT MAINLY DRY WEATHER...CAN BE EXPECTED FOR THE REST OF THE
WEEK AS THE ARCTIC HIGH TO THE NORTH SLIDES SOUTHEAST ACROSS THE
DAKOTAS TODAY AND TONIGHT. SHORT RANGE MODELS ARE IN GOOD AGREEMENT
FOR THE NEXT COUPLE OF DAYS. HIGHS TODAY WILL BE IN THE TEENS...WITH
WIND CHILLS STAYING BELOW ZERO THROUGH MUCH OF THE MORNING. SKIES
WILL CONTINUE TO GRADUALLY CLEAR FROM NORTHEAST TO SOUTHWEST
TODAY...WITH MAINLY SUNNY SKIES IN MOST AREAS BY THE AFTERNOON. WILL
KEEP A SLIGHT CHANCE FOR LIGHT SNOW/FLURRIES ACROSS SOUTHWESTERN
PORTIONS OF NORTHEAST WY...AS WELL AS FAR SOUTHWEST SD...EARLY THIS
MORNING. WILL ALSO KEEP LOW POPS FOR SNOW SHOWERS THIS AFTERNOON
ACROSS THE CENTRAL AND SOUTHERN BLACK HILLS...WHERE STEEP LAPSE
RATES AND SUFFICIENT MOISTURE COULD ALLOW A FEW SHOWERS TO DEVELOP.

BITTER COLD TONIGHT AS HIGH SLIDES SOUTHEAST OF THE REGION AND SKIES
REMAIN MOSTLY CLEAR. LOWS WILL GENERALLY RANGE FROM NEAR 10 BELOW IN
NORTHWEST SD AND THE USUAL COLD SPOTS ELSEWHERE...TO NEAR OR SLIGHT
ABOVE ZERO ACROSS PORTIONS OF NORTHEAST WY WHERE SOUTHERLY WINDS
WILL INCREASE OVERNIGHT.

SOUTH TO SOUTHEAST WINDS WILL INCREASE EVERYWHERE ON FRIDAY AND
BECOME BREEZY ACROSS MUCH OF THE PLAINS BY THE AFTERNOON. MILDER AIR
PUSHING INTO THE AREA WILL ALLOW MOST LOCATIONS TO SEE HIGHS IN THE
20S...WITH SOME SPOTS TO THE SOUTH AND EAST OF THE HILLS NEAR 30.
SKIES WILL BE MOSTLY SUNNY...WITH SOME INCREASE IN CLOUDS FRIDAY
NIGHT OVER SOUTHERN AND WESTERN AREAS AS A STRONG SHORTWAVE DIGS
SOUTHEASTWARD ACROSS THE PACIFIC NW AND GREAT BASIN REGIONS.

.LONG TERM...SATURDAY THROUGH WEDNESDAY
ISSUED AT 305 AM MST THU FEB 26 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND AS A COLD SFC HIGH SETTLES OVER THE AREA. THERE IS A
SLIGHT CHANCE OF VERY LIGHT SNOW OR FLURRIES IN THE BAROCLINIC
ZONE ALONG THE WESTERN EDGE OF THE HIGH OVER NORTHEASTERN
WYOMING...THE BLACK HILLS AND FAR SOUTHWESTERN SOUTH DAKOTA ON
SATURDAY AND SATURDAY NIGHT. DRY WEATHER IS EXPECTED ON SUNDAY.
THE SURFACE HIGH WILL MOVE OFF TO THE EAST ON MONDAY AS THE UPPER
FLOW BECOMES MORE WESTERLY AND WARMER PACIFIC SOURCED AIR PUSHES
INTO THE NORTHERN PLAINS. THE MODELS STILL AGREE ON A BRIEF WARMUP
MONDAY. THE LATEST RUN OF THE ECMWF IS NOW COMING MORE IN LINE
WITH THE GFS IN SWINGING THE NEXT COLD FRONT ACROSS THE AREA ON
TUESDAY...ALTHOUGH THE ECMWF TIMING OF THE FRONT STILL LAGS BEHIND
THE GFS BY AROUND 6 HOURS. HAVE LOWERED TUESDAY HIGHS OVER NERN
WYOMING TO COME MORE IN LINE WITH THE EARLIER FRONTAL PASSAGE.
LOOKS LIKE A CHANCE OF SNOW OVER NERN WY AND FAR WRN SD ON
TUES/TUES NIGHT AS COLDER AIR FLOWS IN BEHIND THE FRONT. THERE IS
A SLIGHT CHANCE OF SNOW OVER SOUTHWESTERN AND SOUTH CENTRAL SOUTH
DAKOTA ON WEDNESDAY AS THOSE AREAS WILL BE ON THE NORTHERN EDGE OF
A BAND OF SNOW ASSOCIATED WITH ISENTROPIC LIFT AHEAD OF AN UPPER
TROUGH MOVING INTO THE CENTRAL PLAINS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY)
ISSUED AT 1034 AM MST THU FEB 26 2015

MVFR CIGS WILL PERSIST ACROSS NORTHEAST WYOMING INTO SOUTHWEST
SOUTH DAKOTA THIS AFTERNOON...WITH CONDITIONS BECOMING VFR THIS
EVENING. VFR ELSEWHERE.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...26
LONG TERM...10
AVIATION...7






000
FXUS63 KUNR 261735
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1035 AM MST THU FEB 26 2015

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
ISSUED AT 305 AM MST THU FEB 26 2015

CURRENT SURFACE ANALYSIS SHOWS ARCTIC HIGH PRESSURE CENTERED OVER
SOUTHERN SK...MOVING SOUTHEASTWARD TOWARD THE DAKOTAS. UPPER LEVEL
ANALYSIS SHOWS LOW NEAR HUDSON BAY...WITH LARGE SCALE TROF
COVERING MUCH OF NORTH AMERICA AT THE MOMENT. PERSISTENT NORTHWEST
FLOW IS IN PLACE OVER THE NORTHERN PLAINS. SKIES ARE STILL MOSTLY
CLOUDY ACROSS MUCH OF THE CWA...WITH SOME CLEARING OVER NORTHWEST
SD. THIS CLEARING WILL SLOWLY MOVE SOUTH AND WEST ACROSS THE CWA
THIS MORNING. KUDX RADAR STILL SHOWS SOME FLURRIES ACROSS THE
BLACK HILLS AND SOUTHWEST SD...BUT THE DRYING TREND WILL CONTINUE
TO MOVE SOUTHWESTWARD EARLY THIS MORNING. TEMPS RANGE FROM AROUND
5 BELOW OVER FAR NORTHWESTERN SD...WHERE SKIES HAVE CLEARED
OUT...TO NEAR 10 ABOVE ACROSS FAR SOUTHWEST SD. WINDS ARE MOSTLY
FROM THE NORTH AT 5 TO 10 MPH...HELPING TO PRODUCE WIND CHILLS TO
AROUND 20 BELOW ZERO ACROSS NORTHWEST SD.

COLD...BUT MAINLY DRY WEATHER...CAN BE EXPECTED FOR THE REST OF THE
WEEK AS THE ARCTIC HIGH TO THE NORTH SLIDES SOUTHEAST ACROSS THE
DAKOTAS TODAY AND TONIGHT. SHORT RANGE MODELS ARE IN GOOD AGREEMENT
FOR THE NEXT COUPLE OF DAYS. HIGHS TODAY WILL BE IN THE TEENS...WITH
WIND CHILLS STAYING BELOW ZERO THROUGH MUCH OF THE MORNING. SKIES
WILL CONTINUE TO GRADUALLY CLEAR FROM NORTHEAST TO SOUTHWEST
TODAY...WITH MAINLY SUNNY SKIES IN MOST AREAS BY THE AFTERNOON. WILL
KEEP A SLIGHT CHANCE FOR LIGHT SNOW/FLURRIES ACROSS SOUTHWESTERN
PORTIONS OF NORTHEAST WY...AS WELL AS FAR SOUTHWEST SD...EARLY THIS
MORNING. WILL ALSO KEEP LOW POPS FOR SNOW SHOWERS THIS AFTERNOON
ACROSS THE CENTRAL AND SOUTHERN BLACK HILLS...WHERE STEEP LAPSE
RATES AND SUFFICIENT MOISTURE COULD ALLOW A FEW SHOWERS TO DEVELOP.

BITTER COLD TONIGHT AS HIGH SLIDES SOUTHEAST OF THE REGION AND SKIES
REMAIN MOSTLY CLEAR. LOWS WILL GENERALLY RANGE FROM NEAR 10 BELOW IN
NORTHWEST SD AND THE USUAL COLD SPOTS ELSEWHERE...TO NEAR OR SLIGHT
ABOVE ZERO ACROSS PORTIONS OF NORTHEAST WY WHERE SOUTHERLY WINDS
WILL INCREASE OVERNIGHT.

SOUTH TO SOUTHEAST WINDS WILL INCREASE EVERYWHERE ON FRIDAY AND
BECOME BREEZY ACROSS MUCH OF THE PLAINS BY THE AFTERNOON. MILDER AIR
PUSHING INTO THE AREA WILL ALLOW MOST LOCATIONS TO SEE HIGHS IN THE
20S...WITH SOME SPOTS TO THE SOUTH AND EAST OF THE HILLS NEAR 30.
SKIES WILL BE MOSTLY SUNNY...WITH SOME INCREASE IN CLOUDS FRIDAY
NIGHT OVER SOUTHERN AND WESTERN AREAS AS A STRONG SHORTWAVE DIGS
SOUTHEASTWARD ACROSS THE PACIFIC NW AND GREAT BASIN REGIONS.

.LONG TERM...SATURDAY THROUGH WEDNESDAY
ISSUED AT 305 AM MST THU FEB 26 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND AS A COLD SFC HIGH SETTLES OVER THE AREA. THERE IS A
SLIGHT CHANCE OF VERY LIGHT SNOW OR FLURRIES IN THE BAROCLINIC
ZONE ALONG THE WESTERN EDGE OF THE HIGH OVER NORTHEASTERN
WYOMING...THE BLACK HILLS AND FAR SOUTHWESTERN SOUTH DAKOTA ON
SATURDAY AND SATURDAY NIGHT. DRY WEATHER IS EXPECTED ON SUNDAY.
THE SURFACE HIGH WILL MOVE OFF TO THE EAST ON MONDAY AS THE UPPER
FLOW BECOMES MORE WESTERLY AND WARMER PACIFIC SOURCED AIR PUSHES
INTO THE NORTHERN PLAINS. THE MODELS STILL AGREE ON A BRIEF WARMUP
MONDAY. THE LATEST RUN OF THE ECMWF IS NOW COMING MORE IN LINE
WITH THE GFS IN SWINGING THE NEXT COLD FRONT ACROSS THE AREA ON
TUESDAY...ALTHOUGH THE ECMWF TIMING OF THE FRONT STILL LAGS BEHIND
THE GFS BY AROUND 6 HOURS. HAVE LOWERED TUESDAY HIGHS OVER NERN
WYOMING TO COME MORE IN LINE WITH THE EARLIER FRONTAL PASSAGE.
LOOKS LIKE A CHANCE OF SNOW OVER NERN WY AND FAR WRN SD ON
TUES/TUES NIGHT AS COLDER AIR FLOWS IN BEHIND THE FRONT. THERE IS
A SLIGHT CHANCE OF SNOW OVER SOUTHWESTERN AND SOUTH CENTRAL SOUTH
DAKOTA ON WEDNESDAY AS THOSE AREAS WILL BE ON THE NORTHERN EDGE OF
A BAND OF SNOW ASSOCIATED WITH ISENTROPIC LIFT AHEAD OF AN UPPER
TROUGH MOVING INTO THE CENTRAL PLAINS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY)
ISSUED AT 1034 AM MST THU FEB 26 2015

MVFR CIGS WILL PERSIST ACROSS NORTHEAST WYOMING INTO SOUTHWEST
SOUTH DAKOTA THIS AFTERNOON...WITH CONDITIONS BECOMING VFR THIS
EVENING. VFR ELSEWHERE.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...26
LONG TERM...10
AVIATION...7






000
FXUS65 KCYS 261726
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1025 AM MST THU FEB 26 2015

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM MST THU FEB 26 2015

VERY COLD DAY IN STORE FOR THE REGION WITH 700MB TEMPS AROUND -20C
AND WIDESPREAD CLOUD COVER.  HIGHS WILL STRUGGLE TO GET ABOVE 20
WHICH IS AROUND 30 DEGREES BELOW NORMAL FOR LATE FEB.  NOT EXPECTING
MUCH SNOW THROUGH MIDDAY.  ALL MODELS INDICATE LIGHT SNOW DEVELOPING
ALONG INTERSTATE 80 FROM ARLINGTON TO CHEYENNE DURING THE AFTN.
THIS OCCURS AS SFC WINDS BECOMING MORE EASTERLY AND LOW LEVEL UPSLOPE
IMPROVES...ESPECIALLY EAST OF THE LARAMIE RANGE. MAIN CHANGE TO
THE FCST WAS TO INCREASE POPS TO 60-70 PERCENT AND INCREASE QPF
SLIGHTLY DURING THE EVENING ALONG THE CHEYENNE RIDGE. LOW LEVEL WINDS
GO SOUTHEASTERLY AND SOUNDINGS INDICATE DECENT UPWARD MOTION FROM
THE SFC TO AROUND 5000 FT AGL. IT IS INTERESTING TO NOTE THAT THIS
IS ACTUALLY IN THE DENDRITIC GROWTH ZONE SINCE LOW LEVEL TEMPS
ARE SO COLD. WHILE THE SNOWFALL RATES AND WINDS ARE LIKELY NOT
ENOUGH TO WARRANT A WINTER WEATHER ADVISORY...CURRENTLY HAVE
ACCUMULATIONS OF 1-3 INCHES FROM THIS AFTN THROUGH FRI MORNING
FROM THE INTERSTATE 80 SUMMIT TO CHEYENNE. PRECIP CHANCES REALLY
DROP OFF TO THE NORTH AND EAST OF CHEYENNE WITH LESS THAN AN INCH
EXPECTED. ALTHOUGH IFR/LIFR CIGS WILL OCCUR ALONG THE CHEYENNE
RIDGE TONIGHT...SOUNDINGS SUGGEST THE FOG THREAT WILL BE MINIMAL
SO DROPPED THE PATCHY FOG.

REMAINDER OF SHORT TERM WILL FEATURE COLD TEMPS WITH GENERALLY WEAK
WINDS.  SOUTHERLY SFC WINDS OVER THE PLAINS THROUGH THE EARLY AFTN
ON FRI WILL KEEP LOW CLOUDS PERSISTENT...ESPECIALLY ALONG THE
CHEYENNE RIDGE.  TEMPS WILL RISE AROUND 5 DEGREES MOSTLY IN AREAS
THAT CLEAR DURING THE MORNING.  PRECIP CHANCES WILL BE SLIM FROM FRI
MORNING THROUGH MIDDAY SAT.  IT IS AFTER 18Z SAT THAT SCATTERED SNOW
SHOWERS COULD RETURN TO AREAS ALONG THE COLORADO BORDER.  ISENTROPIC
LIFT DEVELOPS BY SAT AFTN BUT MORESO BY SAT EVENING.  THE GFS HAS
BEEN CONSISTENT AT SHOWING THE HIGHEST QPF AMOUNTS (0.05-0.1 INCHES)
FROM MIDDAY SAT INTO THE EVENING.  SO AT THIS POINT IT IS JUST LIGHT
SNOW AMOUNTS...WHICH IS REALLY THE THEME THROUGH THE WEEKEND.

.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM MST THU FEB 26 2015

A CONSENSUS OF THE 00Z MEDIUM RANGE MODEL GUIDANCE MAINTAINS A
POSITIVELY TILTED UPPER TROUGH BISECTING THE NATION FROM NORTHEAST
TO SOUTHWEST...REINFORCED BY PERIODIC SHORTWAVES INTO EARLY NEXT WEEK.
THE TROUGH BEGINS TO SHIFT EASTWARD IN RESPONSE TO FLATTENING OF THE
EASTERN PACIFIC UPSTREAM RIDGE BY MIDWEEK. LOOKING AT A COMPLICATED
SURFACE PATTERN THIS WEEKEND WITH A SERIES OF LOW PRESSURE SYSTEMS
IMPACTING THE FOUR CORNERS ACROSS THE CENTRAL/SOUTHERN ROCKIES AND
HIGH PLAINS. COLD HIGH PRESSURE RIDGE WILL TAKE RESIDENCE ACROSS
THE NORTHERN ROCKIES...PLAINS AND MIDWEST. ABUNDANT PACIFIC MOISTURE
AND FAVORABLE UPSLOPE FLOW WILL RESULT IN WIDESPREAD PRECIPITATION...
WITH FOCUS FOR HEAVIER QPF TO THE SOUTH OF THE CWA THROUGH MONDAY.
INCREASED POPS TO 60-70 PERCENT FOR THE SOUTHERN MOUNTAINS SATURDAY
NIGHT...DECREASING TO 30-50 PERCENT SUNDAY THROUGH MONDAY. BEST
CHANCE FOR MOISTURE FOR THE PLAINS WILL BE SATURDAY NIGHT. SUNDAY`S
TEMPERATURES WILL REMAIN IN THE 20S. A SLIGHT MODERATION IN TEMPERATURES
COMMENCES MONDAY WITH SOUTHERLY FLOW PUSHING THE MERCURY TO LOWER-MID
30S. ANOTHER ARCTIC COLD SURGE ARRIVES TUESDAY WITH CHANCES FOR
LIGHT SNOW INTO WEDNESDAY ALONG WITH MUCH BELOW NORMAL TEMPERATURES.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY MORNING)
ISSUED AT 1025 AM MST THU FEB 26 2015

MVFR/IFR CIGS AND VSBYS WILL AFFECT PARTS OF THE AREA...PRIMARILY
FAR SE WY AND SOUTHERN NEBRASKA TERMINALS...THROUGH THIS EVENING
BEFORE IMPROVING SLOWLY OVERNIGHT INTO FRIDAY MORNING.  AREAS OF
LIGHT SNOW WILL PERSIST OVER SE WY THROUGH THIS EVENING MAINLY
AFFECTING KCYS AND KLAR.

&&

.FIRE WEATHER...
ISSUED AT 249 AM MST THU FEB 26 2015

NO FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK. TEMPERATURES WILL
REMAIN WELL BELOW NORMAL WITH HIGH RELATIVE HUMIDITY VALUES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

SHORT TERM...FINCH
LONG TERM...JAMSKI
AVIATION...JAMSKI
FIRE WEATHER...FINCH



000
FXUS65 KCYS 261034
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
334 AM MST THU FEB 26 2015

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM MST THU FEB 26 2015

VERY COLD DAY IN STORE FOR THE REGION WITH 700MB TEMPS AROUND -20C
AND WIDESPREAD CLOUD COVER.  HIGHS WILL STRUGGLE TO GET ABOVE 20
WHICH IS AROUND 30 DEGREES BELOW NORMAL FOR LATE FEB.  NOT EXPECTING
MUCH SNOW THROUGH MIDDAY.  ALL MODELS INDICATE LIGHT SNOW DEVELOPING
ALONG INTERSTATE 80 FROM ARLINGTON TO CHEYENNE DURING THE AFTN.
THIS OCCURS AS SFC WINDS BECOMING MORE EASTERLY AND LOW LEVEL UPSLOPE
IMPROVES...ESPECIALLY EAST OF THE LARAMIE RANGE. MAIN CHANGE TO
THE FCST WAS TO INCREASE POPS TO 60-70 PERCENT AND INCREASE QPF
SLIGHTLY DURING THE EVENING ALONG THE CHEYENNE RIDGE. LOW LEVEL WINDS
GO SOUTHEASTERLY AND SOUNDINGS INDICATE DECENT UPWARD MOTION FROM
THE SFC TO AROUND 5000 FT AGL. IT IS INTERESTING TO NOTE THAT THIS
IS ACTUALLY IN THE DENDRITIC GROWTH ZONE SINCE LOW LEVEL TEMPS
ARE SO COLD. WHILE THE SNOWFALL RATES AND WINDS ARE LIKELY NOT
ENOUGH TO WARRANT A WINTER WEATHER ADVISORY...CURRENTLY HAVE
ACCUMULATIONS OF 1-3 INCHES FROM THIS AFTN THROUGH FRI MORNING
FROM THE INTERSTATE 80 SUMMIT TO CHEYENNE. PRECIP CHANCES REALLY
DROP OFF TO THE NORTH AND EAST OF CHEYENNE WITH LESS THAN AN INCH
EXPECTED. ALTHOUGH IFR/LIFR CIGS WILL OCCUR ALONG THE CHEYENNE
RIDGE TONIGHT...SOUNDINGS SUGGEST THE FOG THREAT WILL BE MINIMAL
SO DROPPED THE PATCHY FOG.

REMAINDER OF SHORT TERM WILL FEATURE COLD TEMPS WITH GENERALLY WEAK
WINDS.  SOUTHERLY SFC WINDS OVER THE PLAINS THROUGH THE EARLY AFTN
ON FRI WILL KEEP LOW CLOUDS PERSISTENT...ESPECIALLY ALONG THE
CHEYENNE RIDGE.  TEMPS WILL RISE AROUND 5 DEGREES MOSTLY IN AREAS
THAT CLEAR DURING THE MORNING.  PRECIP CHANCES WILL BE SLIM FROM FRI
MORNING THROUGH MIDDAY SAT.  IT IS AFTER 18Z SAT THAT SCATTERED SNOW
SHOWERS COULD RETURN TO AREAS ALONG THE COLORADO BORDER.  ISENTROPIC
LIFT DEVELOPS BY SAT AFTN BUT MORESO BY SAT EVENING.  THE GFS HAS
BEEN CONSISTENT AT SHOWING THE HIGHEST QPF AMOUNTS (0.05-0.1 INCHES)
FROM MIDDAY SAT INTO THE EVENING.  SO AT THIS POINT IT IS JUST LIGHT
SNOW AMOUNTS...WHICH IS REALLY THE THEME THROUGH THE WEEKEND.

.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM MST THU FEB 26 2015

A CONSENSUS OF THE 00Z MEDIUM RANGE MODEL GUIDANCE MAINTAINS A
POSITIVELY TILTED UPPER TROUGH BISECTING THE NATION FROM NORTHEAST
TO SOUTHWEST...REINFORCED BY PERIODIC SHORTWAVES INTO EARLY NEXT WEEK.
THE TROUGH BEGINS TO SHIFT EASTWARD IN RESPONSE TO FLATTENING OF THE
EASTERN PACIFIC UPSTREAM RIDGE BY MIDWEEK. LOOKING AT A COMPLICATED
SURFACE PATTERN THIS WEEKEND WITH A SERIES OF LOW PRESSURE SYSTEMS
IMPACTING THE FOUR CORNERS ACROSS THE CENTRAL/SOUTHERN ROCKIES AND
HIGH PLAINS. COLD HIGH PRESSURE RIDGE WILL TAKE RESIDENCE ACROSS
THE NORTHERN ROCKIES...PLAINS AND MIDWEST. ABUNDANT PACIFIC MOISTURE
AND FAVORABLE UPSLOPE FLOW WILL RESULT IN WIDESPREAD PRECIPITATION...
WITH FOCUS FOR HEAVIER QPF TO THE SOUTH OF THE CWA THROUGH MONDAY.
INCREASED POPS TO 60-70 PERCENT FOR THE SOUTHERN MOUNTAINS SATURDAY
NIGHT...DECREASING TO 30-50 PERCENT SUNDAY THROUGH MONDAY. BEST
CHANCE FOR MOISTURE FOR THE PLAINS WILL BE SATURDAY NIGHT. SUNDAY`S
TEMPERATURES WILL REMAIN IN THE 20S. A SLIGHT MODERATION IN TEMPERATURES
COMMENCES MONDAY WITH SOUTHERLY FLOW PUSHING THE MERCURY TO LOWER-MID
30S. ANOTHER ARCTIC COLD SURGE ARRIVES TUESDAY WITH CHANCES FOR
LIGHT SNOW INTO WEDNESDAY ALONG WITH MUCH BELOW NORMAL TEMPERATURES.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 249 AM MST THU FEB 26 2015

MVFR CIGS WILL PREVAIL AT MOST TERMINALS TODAY AND TONIGHT. PERIODIC
REDUCTIONS TO IFR/LIFR WILL OCCUR IN AREAS OF LIGHT TO MODERATE SNOW
ALONG AND SOUTH OF THE KLAR TO KSNY ROUTE THROUGH THIS EVENING. EAST
TO NORTHEAST SURFACE WINDS WILL AVERAGE 5-12 KT.

&&

.FIRE WEATHER...
ISSUED AT 249 AM MST THU FEB 26 2015

NO FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK. TEMPERATURES WILL
REMAIN WELL BELOW NORMAL WITH HIGH RELATIVE HUMIDITY VALUES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

SHORT TERM...FINCH
LONG TERM...JAMSKI
AVIATION...JAMSKI
FIRE WEATHER...FINCH




000
FXUS65 KCYS 261034
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
334 AM MST THU FEB 26 2015

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM MST THU FEB 26 2015

VERY COLD DAY IN STORE FOR THE REGION WITH 700MB TEMPS AROUND -20C
AND WIDESPREAD CLOUD COVER.  HIGHS WILL STRUGGLE TO GET ABOVE 20
WHICH IS AROUND 30 DEGREES BELOW NORMAL FOR LATE FEB.  NOT EXPECTING
MUCH SNOW THROUGH MIDDAY.  ALL MODELS INDICATE LIGHT SNOW DEVELOPING
ALONG INTERSTATE 80 FROM ARLINGTON TO CHEYENNE DURING THE AFTN.
THIS OCCURS AS SFC WINDS BECOMING MORE EASTERLY AND LOW LEVEL UPSLOPE
IMPROVES...ESPECIALLY EAST OF THE LARAMIE RANGE. MAIN CHANGE TO
THE FCST WAS TO INCREASE POPS TO 60-70 PERCENT AND INCREASE QPF
SLIGHTLY DURING THE EVENING ALONG THE CHEYENNE RIDGE. LOW LEVEL WINDS
GO SOUTHEASTERLY AND SOUNDINGS INDICATE DECENT UPWARD MOTION FROM
THE SFC TO AROUND 5000 FT AGL. IT IS INTERESTING TO NOTE THAT THIS
IS ACTUALLY IN THE DENDRITIC GROWTH ZONE SINCE LOW LEVEL TEMPS
ARE SO COLD. WHILE THE SNOWFALL RATES AND WINDS ARE LIKELY NOT
ENOUGH TO WARRANT A WINTER WEATHER ADVISORY...CURRENTLY HAVE
ACCUMULATIONS OF 1-3 INCHES FROM THIS AFTN THROUGH FRI MORNING
FROM THE INTERSTATE 80 SUMMIT TO CHEYENNE. PRECIP CHANCES REALLY
DROP OFF TO THE NORTH AND EAST OF CHEYENNE WITH LESS THAN AN INCH
EXPECTED. ALTHOUGH IFR/LIFR CIGS WILL OCCUR ALONG THE CHEYENNE
RIDGE TONIGHT...SOUNDINGS SUGGEST THE FOG THREAT WILL BE MINIMAL
SO DROPPED THE PATCHY FOG.

REMAINDER OF SHORT TERM WILL FEATURE COLD TEMPS WITH GENERALLY WEAK
WINDS.  SOUTHERLY SFC WINDS OVER THE PLAINS THROUGH THE EARLY AFTN
ON FRI WILL KEEP LOW CLOUDS PERSISTENT...ESPECIALLY ALONG THE
CHEYENNE RIDGE.  TEMPS WILL RISE AROUND 5 DEGREES MOSTLY IN AREAS
THAT CLEAR DURING THE MORNING.  PRECIP CHANCES WILL BE SLIM FROM FRI
MORNING THROUGH MIDDAY SAT.  IT IS AFTER 18Z SAT THAT SCATTERED SNOW
SHOWERS COULD RETURN TO AREAS ALONG THE COLORADO BORDER.  ISENTROPIC
LIFT DEVELOPS BY SAT AFTN BUT MORESO BY SAT EVENING.  THE GFS HAS
BEEN CONSISTENT AT SHOWING THE HIGHEST QPF AMOUNTS (0.05-0.1 INCHES)
FROM MIDDAY SAT INTO THE EVENING.  SO AT THIS POINT IT IS JUST LIGHT
SNOW AMOUNTS...WHICH IS REALLY THE THEME THROUGH THE WEEKEND.

.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM MST THU FEB 26 2015

A CONSENSUS OF THE 00Z MEDIUM RANGE MODEL GUIDANCE MAINTAINS A
POSITIVELY TILTED UPPER TROUGH BISECTING THE NATION FROM NORTHEAST
TO SOUTHWEST...REINFORCED BY PERIODIC SHORTWAVES INTO EARLY NEXT WEEK.
THE TROUGH BEGINS TO SHIFT EASTWARD IN RESPONSE TO FLATTENING OF THE
EASTERN PACIFIC UPSTREAM RIDGE BY MIDWEEK. LOOKING AT A COMPLICATED
SURFACE PATTERN THIS WEEKEND WITH A SERIES OF LOW PRESSURE SYSTEMS
IMPACTING THE FOUR CORNERS ACROSS THE CENTRAL/SOUTHERN ROCKIES AND
HIGH PLAINS. COLD HIGH PRESSURE RIDGE WILL TAKE RESIDENCE ACROSS
THE NORTHERN ROCKIES...PLAINS AND MIDWEST. ABUNDANT PACIFIC MOISTURE
AND FAVORABLE UPSLOPE FLOW WILL RESULT IN WIDESPREAD PRECIPITATION...
WITH FOCUS FOR HEAVIER QPF TO THE SOUTH OF THE CWA THROUGH MONDAY.
INCREASED POPS TO 60-70 PERCENT FOR THE SOUTHERN MOUNTAINS SATURDAY
NIGHT...DECREASING TO 30-50 PERCENT SUNDAY THROUGH MONDAY. BEST
CHANCE FOR MOISTURE FOR THE PLAINS WILL BE SATURDAY NIGHT. SUNDAY`S
TEMPERATURES WILL REMAIN IN THE 20S. A SLIGHT MODERATION IN TEMPERATURES
COMMENCES MONDAY WITH SOUTHERLY FLOW PUSHING THE MERCURY TO LOWER-MID
30S. ANOTHER ARCTIC COLD SURGE ARRIVES TUESDAY WITH CHANCES FOR
LIGHT SNOW INTO WEDNESDAY ALONG WITH MUCH BELOW NORMAL TEMPERATURES.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 249 AM MST THU FEB 26 2015

MVFR CIGS WILL PREVAIL AT MOST TERMINALS TODAY AND TONIGHT. PERIODIC
REDUCTIONS TO IFR/LIFR WILL OCCUR IN AREAS OF LIGHT TO MODERATE SNOW
ALONG AND SOUTH OF THE KLAR TO KSNY ROUTE THROUGH THIS EVENING. EAST
TO NORTHEAST SURFACE WINDS WILL AVERAGE 5-12 KT.

&&

.FIRE WEATHER...
ISSUED AT 249 AM MST THU FEB 26 2015

NO FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK. TEMPERATURES WILL
REMAIN WELL BELOW NORMAL WITH HIGH RELATIVE HUMIDITY VALUES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

SHORT TERM...FINCH
LONG TERM...JAMSKI
AVIATION...JAMSKI
FIRE WEATHER...FINCH




000
FXUS65 KCYS 261034
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
334 AM MST THU FEB 26 2015

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM MST THU FEB 26 2015

VERY COLD DAY IN STORE FOR THE REGION WITH 700MB TEMPS AROUND -20C
AND WIDESPREAD CLOUD COVER.  HIGHS WILL STRUGGLE TO GET ABOVE 20
WHICH IS AROUND 30 DEGREES BELOW NORMAL FOR LATE FEB.  NOT EXPECTING
MUCH SNOW THROUGH MIDDAY.  ALL MODELS INDICATE LIGHT SNOW DEVELOPING
ALONG INTERSTATE 80 FROM ARLINGTON TO CHEYENNE DURING THE AFTN.
THIS OCCURS AS SFC WINDS BECOMING MORE EASTERLY AND LOW LEVEL UPSLOPE
IMPROVES...ESPECIALLY EAST OF THE LARAMIE RANGE. MAIN CHANGE TO
THE FCST WAS TO INCREASE POPS TO 60-70 PERCENT AND INCREASE QPF
SLIGHTLY DURING THE EVENING ALONG THE CHEYENNE RIDGE. LOW LEVEL WINDS
GO SOUTHEASTERLY AND SOUNDINGS INDICATE DECENT UPWARD MOTION FROM
THE SFC TO AROUND 5000 FT AGL. IT IS INTERESTING TO NOTE THAT THIS
IS ACTUALLY IN THE DENDRITIC GROWTH ZONE SINCE LOW LEVEL TEMPS
ARE SO COLD. WHILE THE SNOWFALL RATES AND WINDS ARE LIKELY NOT
ENOUGH TO WARRANT A WINTER WEATHER ADVISORY...CURRENTLY HAVE
ACCUMULATIONS OF 1-3 INCHES FROM THIS AFTN THROUGH FRI MORNING
FROM THE INTERSTATE 80 SUMMIT TO CHEYENNE. PRECIP CHANCES REALLY
DROP OFF TO THE NORTH AND EAST OF CHEYENNE WITH LESS THAN AN INCH
EXPECTED. ALTHOUGH IFR/LIFR CIGS WILL OCCUR ALONG THE CHEYENNE
RIDGE TONIGHT...SOUNDINGS SUGGEST THE FOG THREAT WILL BE MINIMAL
SO DROPPED THE PATCHY FOG.

REMAINDER OF SHORT TERM WILL FEATURE COLD TEMPS WITH GENERALLY WEAK
WINDS.  SOUTHERLY SFC WINDS OVER THE PLAINS THROUGH THE EARLY AFTN
ON FRI WILL KEEP LOW CLOUDS PERSISTENT...ESPECIALLY ALONG THE
CHEYENNE RIDGE.  TEMPS WILL RISE AROUND 5 DEGREES MOSTLY IN AREAS
THAT CLEAR DURING THE MORNING.  PRECIP CHANCES WILL BE SLIM FROM FRI
MORNING THROUGH MIDDAY SAT.  IT IS AFTER 18Z SAT THAT SCATTERED SNOW
SHOWERS COULD RETURN TO AREAS ALONG THE COLORADO BORDER.  ISENTROPIC
LIFT DEVELOPS BY SAT AFTN BUT MORESO BY SAT EVENING.  THE GFS HAS
BEEN CONSISTENT AT SHOWING THE HIGHEST QPF AMOUNTS (0.05-0.1 INCHES)
FROM MIDDAY SAT INTO THE EVENING.  SO AT THIS POINT IT IS JUST LIGHT
SNOW AMOUNTS...WHICH IS REALLY THE THEME THROUGH THE WEEKEND.

.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM MST THU FEB 26 2015

A CONSENSUS OF THE 00Z MEDIUM RANGE MODEL GUIDANCE MAINTAINS A
POSITIVELY TILTED UPPER TROUGH BISECTING THE NATION FROM NORTHEAST
TO SOUTHWEST...REINFORCED BY PERIODIC SHORTWAVES INTO EARLY NEXT WEEK.
THE TROUGH BEGINS TO SHIFT EASTWARD IN RESPONSE TO FLATTENING OF THE
EASTERN PACIFIC UPSTREAM RIDGE BY MIDWEEK. LOOKING AT A COMPLICATED
SURFACE PATTERN THIS WEEKEND WITH A SERIES OF LOW PRESSURE SYSTEMS
IMPACTING THE FOUR CORNERS ACROSS THE CENTRAL/SOUTHERN ROCKIES AND
HIGH PLAINS. COLD HIGH PRESSURE RIDGE WILL TAKE RESIDENCE ACROSS
THE NORTHERN ROCKIES...PLAINS AND MIDWEST. ABUNDANT PACIFIC MOISTURE
AND FAVORABLE UPSLOPE FLOW WILL RESULT IN WIDESPREAD PRECIPITATION...
WITH FOCUS FOR HEAVIER QPF TO THE SOUTH OF THE CWA THROUGH MONDAY.
INCREASED POPS TO 60-70 PERCENT FOR THE SOUTHERN MOUNTAINS SATURDAY
NIGHT...DECREASING TO 30-50 PERCENT SUNDAY THROUGH MONDAY. BEST
CHANCE FOR MOISTURE FOR THE PLAINS WILL BE SATURDAY NIGHT. SUNDAY`S
TEMPERATURES WILL REMAIN IN THE 20S. A SLIGHT MODERATION IN TEMPERATURES
COMMENCES MONDAY WITH SOUTHERLY FLOW PUSHING THE MERCURY TO LOWER-MID
30S. ANOTHER ARCTIC COLD SURGE ARRIVES TUESDAY WITH CHANCES FOR
LIGHT SNOW INTO WEDNESDAY ALONG WITH MUCH BELOW NORMAL TEMPERATURES.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 249 AM MST THU FEB 26 2015

MVFR CIGS WILL PREVAIL AT MOST TERMINALS TODAY AND TONIGHT. PERIODIC
REDUCTIONS TO IFR/LIFR WILL OCCUR IN AREAS OF LIGHT TO MODERATE SNOW
ALONG AND SOUTH OF THE KLAR TO KSNY ROUTE THROUGH THIS EVENING. EAST
TO NORTHEAST SURFACE WINDS WILL AVERAGE 5-12 KT.

&&

.FIRE WEATHER...
ISSUED AT 249 AM MST THU FEB 26 2015

NO FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK. TEMPERATURES WILL
REMAIN WELL BELOW NORMAL WITH HIGH RELATIVE HUMIDITY VALUES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

SHORT TERM...FINCH
LONG TERM...JAMSKI
AVIATION...JAMSKI
FIRE WEATHER...FINCH




000
FXUS65 KCYS 261034
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
334 AM MST THU FEB 26 2015

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM MST THU FEB 26 2015

VERY COLD DAY IN STORE FOR THE REGION WITH 700MB TEMPS AROUND -20C
AND WIDESPREAD CLOUD COVER.  HIGHS WILL STRUGGLE TO GET ABOVE 20
WHICH IS AROUND 30 DEGREES BELOW NORMAL FOR LATE FEB.  NOT EXPECTING
MUCH SNOW THROUGH MIDDAY.  ALL MODELS INDICATE LIGHT SNOW DEVELOPING
ALONG INTERSTATE 80 FROM ARLINGTON TO CHEYENNE DURING THE AFTN.
THIS OCCURS AS SFC WINDS BECOMING MORE EASTERLY AND LOW LEVEL UPSLOPE
IMPROVES...ESPECIALLY EAST OF THE LARAMIE RANGE. MAIN CHANGE TO
THE FCST WAS TO INCREASE POPS TO 60-70 PERCENT AND INCREASE QPF
SLIGHTLY DURING THE EVENING ALONG THE CHEYENNE RIDGE. LOW LEVEL WINDS
GO SOUTHEASTERLY AND SOUNDINGS INDICATE DECENT UPWARD MOTION FROM
THE SFC TO AROUND 5000 FT AGL. IT IS INTERESTING TO NOTE THAT THIS
IS ACTUALLY IN THE DENDRITIC GROWTH ZONE SINCE LOW LEVEL TEMPS
ARE SO COLD. WHILE THE SNOWFALL RATES AND WINDS ARE LIKELY NOT
ENOUGH TO WARRANT A WINTER WEATHER ADVISORY...CURRENTLY HAVE
ACCUMULATIONS OF 1-3 INCHES FROM THIS AFTN THROUGH FRI MORNING
FROM THE INTERSTATE 80 SUMMIT TO CHEYENNE. PRECIP CHANCES REALLY
DROP OFF TO THE NORTH AND EAST OF CHEYENNE WITH LESS THAN AN INCH
EXPECTED. ALTHOUGH IFR/LIFR CIGS WILL OCCUR ALONG THE CHEYENNE
RIDGE TONIGHT...SOUNDINGS SUGGEST THE FOG THREAT WILL BE MINIMAL
SO DROPPED THE PATCHY FOG.

REMAINDER OF SHORT TERM WILL FEATURE COLD TEMPS WITH GENERALLY WEAK
WINDS.  SOUTHERLY SFC WINDS OVER THE PLAINS THROUGH THE EARLY AFTN
ON FRI WILL KEEP LOW CLOUDS PERSISTENT...ESPECIALLY ALONG THE
CHEYENNE RIDGE.  TEMPS WILL RISE AROUND 5 DEGREES MOSTLY IN AREAS
THAT CLEAR DURING THE MORNING.  PRECIP CHANCES WILL BE SLIM FROM FRI
MORNING THROUGH MIDDAY SAT.  IT IS AFTER 18Z SAT THAT SCATTERED SNOW
SHOWERS COULD RETURN TO AREAS ALONG THE COLORADO BORDER.  ISENTROPIC
LIFT DEVELOPS BY SAT AFTN BUT MORESO BY SAT EVENING.  THE GFS HAS
BEEN CONSISTENT AT SHOWING THE HIGHEST QPF AMOUNTS (0.05-0.1 INCHES)
FROM MIDDAY SAT INTO THE EVENING.  SO AT THIS POINT IT IS JUST LIGHT
SNOW AMOUNTS...WHICH IS REALLY THE THEME THROUGH THE WEEKEND.

.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM MST THU FEB 26 2015

A CONSENSUS OF THE 00Z MEDIUM RANGE MODEL GUIDANCE MAINTAINS A
POSITIVELY TILTED UPPER TROUGH BISECTING THE NATION FROM NORTHEAST
TO SOUTHWEST...REINFORCED BY PERIODIC SHORTWAVES INTO EARLY NEXT WEEK.
THE TROUGH BEGINS TO SHIFT EASTWARD IN RESPONSE TO FLATTENING OF THE
EASTERN PACIFIC UPSTREAM RIDGE BY MIDWEEK. LOOKING AT A COMPLICATED
SURFACE PATTERN THIS WEEKEND WITH A SERIES OF LOW PRESSURE SYSTEMS
IMPACTING THE FOUR CORNERS ACROSS THE CENTRAL/SOUTHERN ROCKIES AND
HIGH PLAINS. COLD HIGH PRESSURE RIDGE WILL TAKE RESIDENCE ACROSS
THE NORTHERN ROCKIES...PLAINS AND MIDWEST. ABUNDANT PACIFIC MOISTURE
AND FAVORABLE UPSLOPE FLOW WILL RESULT IN WIDESPREAD PRECIPITATION...
WITH FOCUS FOR HEAVIER QPF TO THE SOUTH OF THE CWA THROUGH MONDAY.
INCREASED POPS TO 60-70 PERCENT FOR THE SOUTHERN MOUNTAINS SATURDAY
NIGHT...DECREASING TO 30-50 PERCENT SUNDAY THROUGH MONDAY. BEST
CHANCE FOR MOISTURE FOR THE PLAINS WILL BE SATURDAY NIGHT. SUNDAY`S
TEMPERATURES WILL REMAIN IN THE 20S. A SLIGHT MODERATION IN TEMPERATURES
COMMENCES MONDAY WITH SOUTHERLY FLOW PUSHING THE MERCURY TO LOWER-MID
30S. ANOTHER ARCTIC COLD SURGE ARRIVES TUESDAY WITH CHANCES FOR
LIGHT SNOW INTO WEDNESDAY ALONG WITH MUCH BELOW NORMAL TEMPERATURES.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 249 AM MST THU FEB 26 2015

MVFR CIGS WILL PREVAIL AT MOST TERMINALS TODAY AND TONIGHT. PERIODIC
REDUCTIONS TO IFR/LIFR WILL OCCUR IN AREAS OF LIGHT TO MODERATE SNOW
ALONG AND SOUTH OF THE KLAR TO KSNY ROUTE THROUGH THIS EVENING. EAST
TO NORTHEAST SURFACE WINDS WILL AVERAGE 5-12 KT.

&&

.FIRE WEATHER...
ISSUED AT 249 AM MST THU FEB 26 2015

NO FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK. TEMPERATURES WILL
REMAIN WELL BELOW NORMAL WITH HIGH RELATIVE HUMIDITY VALUES.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

SHORT TERM...FINCH
LONG TERM...JAMSKI
AVIATION...JAMSKI
FIRE WEATHER...FINCH




000
FXUS63 KUNR 261006
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
306 AM MST THU FEB 26 2015

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
ISSUED AT 305 AM MST THU FEB 26 2015

CURRENT SURFACE ANALYSIS SHOWS ARCTIC HIGH PRESSURE CENTERED OVER
SOUTHERN SK...MOVING SOUTHEASTWARD TOWARD THE DAKOTAS. UPPER LEVEL
ANALYSIS SHOWS LOW NEAR HUDSON BAY...WITH LARGE SCALE TROF
COVERING MUCH OF NORTH AMERICA AT THE MOMENT. PERSISTENT NORTHWEST
FLOW IS IN PLACE OVER THE NORTHERN PLAINS. SKIES ARE STILL MOSTLY
CLOUDY ACROSS MUCH OF THE CWA...WITH SOME CLEARING OVER NORTHWEST
SD. THIS CLEARING WILL SLOWLY MOVE SOUTH AND WEST ACROSS THE CWA
THIS MORNING. KUDX RADAR STILL SHOWS SOME FLURRIES ACROSS THE
BLACK HILLS AND SOUTHWEST SD...BUT THE DRYING TREND WILL CONTINUE
TO MOVE SOUTHWESTWARD EARLY THIS MORNING. TEMPS RANGE FROM AROUND
5 BELOW OVER FAR NORTHWESTERN SD...WHERE SKIES HAVE CLEARED
OUT...TO NEAR 10 ABOVE ACROSS FAR SOUTHWEST SD. WINDS ARE MOSTLY
FROM THE NORTH AT 5 TO 10 MPH...HELPING TO PRODUCE WIND CHILLS TO
AROUND 20 BELOW ZERO ACROSS NORTHWEST SD.

COLD...BUT MAINLY DRY WEATHER...CAN BE EXPECTED FOR THE REST OF THE
WEEK AS THE ARCTIC HIGH TO THE NORTH SLIDES SOUTHEAST ACROSS THE
DAKOTAS TODAY AND TONIGHT. SHORT RANGE MODELS ARE IN GOOD AGREEMENT
FOR THE NEXT COUPLE OF DAYS. HIGHS TODAY WILL BE IN THE TEENS...WITH
WIND CHILLS STAYING BELOW ZERO THROUGH MUCH OF THE MORNING. SKIES
WILL CONTINUE TO GRADUALLY CLEAR FROM NORTHEAST TO SOUTHWEST
TODAY...WITH MAINLY SUNNY SKIES IN MOST AREAS BY THE AFTERNOON. WILL
KEEP A SLIGHT CHANCE FOR LIGHT SNOW/FLURRIES ACROSS SOUTHWESTERN
PORTIONS OF NORTHEAST WY...AS WELL AS FAR SOUTHWEST SD...EARLY THIS
MORNING. WILL ALSO KEEP LOW POPS FOR SNOW SHOWERS THIS AFTERNOON
ACROSS THE CENTRAL AND SOUTHERN BLACK HILLS...WHERE STEEP LAPSE
RATES AND SUFFICIENT MOISTURE COULD ALLOW A FEW SHOWERS TO DEVELOP.

BITTER COLD TONIGHT AS HIGH SLIDES SOUTHEAST OF THE REGION AND SKIES
REMAIN MOSTLY CLEAR. LOWS WILL GENERALLY RANGE FROM NEAR 10 BELOW IN
NORTHWEST SD AND THE USUAL COLD SPOTS ELSEWHERE...TO NEAR OR SLIGHT
ABOVE ZERO ACROSS PORTIONS OF NORTHEAST WY WHERE SOUTHERLY WINDS
WILL INCREASE OVERNIGHT.

SOUTH TO SOUTHEAST WINDS WILL INCREASE EVERYWHERE ON FRIDAY AND
BECOME BREEZY ACROSS MUCH OF THE PLAINS BY THE AFTERNOON. MILDER AIR
PUSHING INTO THE AREA WILL ALLOW MOST LOCATIONS TO SEE HIGHS IN THE
20S...WITH SOME SPOTS TO THE SOUTH AND EAST OF THE HILLS NEAR 30.
SKIES WILL BE MOSTLY SUNNY...WITH SOME INCREASE IN CLOUDS FRIDAY
NIGHT OVER SOUTHERN AND WESTERN AREAS AS A STRONG SHORTWAVE DIGS
SOUTHEASTWARD ACROSS THE PACIFIC NW AND GREAT BASIN REGIONS.

.LONG TERM...SATURDAY THROUGH WEDNESDAY
ISSUED AT 305 AM MST THU FEB 26 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND AS A COLD SFC HIGH SETTLES OVER THE AREA. THERE IS A
SLIGHT CHANCE OF VERY LIGHT SNOW OR FLURRIES IN THE BAROCLINIC
ZONE ALONG THE WESTERN EDGE OF THE HIGH OVER NORTHEASTERN
WYOMING...THE BLACK HILLS AND FAR SOUTHWESTERN SOUTH DAKOTA ON
SATURDAY AND SATURDAY NIGHT. DRY WEATHER IS EXPECTED ON SUNDAY.
THE SURFACE HIGH WILL MOVE OFF TO THE EAST ON MONDAY AS THE UPPER
FLOW BECOMES MORE WESTERLY AND WARMER PACIFIC SOURCED AIR PUSHES
INTO THE NORTHERN PLAINS. THE MODELS STILL AGREE ON A BRIEF WARMUP
MONDAY. THE LATEST RUN OF THE ECMWF IS NOW COMING MORE IN LINE
WITH THE GFS IN SWINGING THE NEXT COLD FRONT ACROSS THE AREA ON
TUESDAY...ALTHOUGH THE ECMWF TIMING OF THE FRONT STILL LAGS BEHIND
THE GFS BY AROUND 6 HOURS. HAVE LOWERED TUESDAY HIGHS OVER NERN
WYOMING TO COME MORE IN LINE WITH THE EARLIER FRONTAL PASSAGE.
LOOKS LIKE A CHANCE OF SNOW OVER NERN WY AND FAR WRN SD ON
TUES/TUES NIGHT AS COLDER AIR FLOWS IN BEHIND THE FRONT. THERE IS
A SLIGHT CHANCE OF SNOW OVER SOUTHWESTERN AND SOUTH CENTRAL SOUTH
DAKOTA ON WEDNESDAY AS THOSE AREAS WILL BE ON THE NORTHERN EDGE OF
A BAND OF SNOW ASSOCIATED WITH ISENTROPIC LIFT AHEAD OF AN UPPER
TROUGH MOVING INTO THE CENTRAL PLAINS.

&&

.AVIATION...FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING
ISSUED AT 305 AM MST THU FEB 26 2015

IFR/MVFR CIGS/VSBYS IN -SN OR FLURRIES CURRENTLY LOCATED
OVER THE BLACK HILLS...AND PARTS OF SWRN SD AND NERN WY WILL
CONTINUE TO MOVE OFF TO THE SOUTHWEST THIS MORNING...WITH VFR
CONDITIONS MOVING IN FROM THE NORTHEAST AS DRIER AIR FILTERS IN.
THERE IS A CHANCE OF -SHSN OVER THE BLACK HILLS THIS AFTERNOON WITH
LCL IFR CIGS POSSIBLE IN ANY -SHSN.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...26
LONG TERM...10
AVIATION...10







000
FXUS63 KUNR 261006
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
306 AM MST THU FEB 26 2015

.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
ISSUED AT 305 AM MST THU FEB 26 2015

CURRENT SURFACE ANALYSIS SHOWS ARCTIC HIGH PRESSURE CENTERED OVER
SOUTHERN SK...MOVING SOUTHEASTWARD TOWARD THE DAKOTAS. UPPER LEVEL
ANALYSIS SHOWS LOW NEAR HUDSON BAY...WITH LARGE SCALE TROF
COVERING MUCH OF NORTH AMERICA AT THE MOMENT. PERSISTENT NORTHWEST
FLOW IS IN PLACE OVER THE NORTHERN PLAINS. SKIES ARE STILL MOSTLY
CLOUDY ACROSS MUCH OF THE CWA...WITH SOME CLEARING OVER NORTHWEST
SD. THIS CLEARING WILL SLOWLY MOVE SOUTH AND WEST ACROSS THE CWA
THIS MORNING. KUDX RADAR STILL SHOWS SOME FLURRIES ACROSS THE
BLACK HILLS AND SOUTHWEST SD...BUT THE DRYING TREND WILL CONTINUE
TO MOVE SOUTHWESTWARD EARLY THIS MORNING. TEMPS RANGE FROM AROUND
5 BELOW OVER FAR NORTHWESTERN SD...WHERE SKIES HAVE CLEARED
OUT...TO NEAR 10 ABOVE ACROSS FAR SOUTHWEST SD. WINDS ARE MOSTLY
FROM THE NORTH AT 5 TO 10 MPH...HELPING TO PRODUCE WIND CHILLS TO
AROUND 20 BELOW ZERO ACROSS NORTHWEST SD.

COLD...BUT MAINLY DRY WEATHER...CAN BE EXPECTED FOR THE REST OF THE
WEEK AS THE ARCTIC HIGH TO THE NORTH SLIDES SOUTHEAST ACROSS THE
DAKOTAS TODAY AND TONIGHT. SHORT RANGE MODELS ARE IN GOOD AGREEMENT
FOR THE NEXT COUPLE OF DAYS. HIGHS TODAY WILL BE IN THE TEENS...WITH
WIND CHILLS STAYING BELOW ZERO THROUGH MUCH OF THE MORNING. SKIES
WILL CONTINUE TO GRADUALLY CLEAR FROM NORTHEAST TO SOUTHWEST
TODAY...WITH MAINLY SUNNY SKIES IN MOST AREAS BY THE AFTERNOON. WILL
KEEP A SLIGHT CHANCE FOR LIGHT SNOW/FLURRIES ACROSS SOUTHWESTERN
PORTIONS OF NORTHEAST WY...AS WELL AS FAR SOUTHWEST SD...EARLY THIS
MORNING. WILL ALSO KEEP LOW POPS FOR SNOW SHOWERS THIS AFTERNOON
ACROSS THE CENTRAL AND SOUTHERN BLACK HILLS...WHERE STEEP LAPSE
RATES AND SUFFICIENT MOISTURE COULD ALLOW A FEW SHOWERS TO DEVELOP.

BITTER COLD TONIGHT AS HIGH SLIDES SOUTHEAST OF THE REGION AND SKIES
REMAIN MOSTLY CLEAR. LOWS WILL GENERALLY RANGE FROM NEAR 10 BELOW IN
NORTHWEST SD AND THE USUAL COLD SPOTS ELSEWHERE...TO NEAR OR SLIGHT
ABOVE ZERO ACROSS PORTIONS OF NORTHEAST WY WHERE SOUTHERLY WINDS
WILL INCREASE OVERNIGHT.

SOUTH TO SOUTHEAST WINDS WILL INCREASE EVERYWHERE ON FRIDAY AND
BECOME BREEZY ACROSS MUCH OF THE PLAINS BY THE AFTERNOON. MILDER AIR
PUSHING INTO THE AREA WILL ALLOW MOST LOCATIONS TO SEE HIGHS IN THE
20S...WITH SOME SPOTS TO THE SOUTH AND EAST OF THE HILLS NEAR 30.
SKIES WILL BE MOSTLY SUNNY...WITH SOME INCREASE IN CLOUDS FRIDAY
NIGHT OVER SOUTHERN AND WESTERN AREAS AS A STRONG SHORTWAVE DIGS
SOUTHEASTWARD ACROSS THE PACIFIC NW AND GREAT BASIN REGIONS.

.LONG TERM...SATURDAY THROUGH WEDNESDAY
ISSUED AT 305 AM MST THU FEB 26 2015

COLDER THAN AVERAGE TEMPERATURES WILL CONTINUE THROUGH THE
WEEKEND AS A COLD SFC HIGH SETTLES OVER THE AREA. THERE IS A
SLIGHT CHANCE OF VERY LIGHT SNOW OR FLURRIES IN THE BAROCLINIC
ZONE ALONG THE WESTERN EDGE OF THE HIGH OVER NORTHEASTERN
WYOMING...THE BLACK HILLS AND FAR SOUTHWESTERN SOUTH DAKOTA ON
SATURDAY AND SATURDAY NIGHT. DRY WEATHER IS EXPECTED ON SUNDAY.
THE SURFACE HIGH WILL MOVE OFF TO THE EAST ON MONDAY AS THE UPPER
FLOW BECOMES MORE WESTERLY AND WARMER PACIFIC SOURCED AIR PUSHES
INTO THE NORTHERN PLAINS. THE MODELS STILL AGREE ON A BRIEF WARMUP
MONDAY. THE LATEST RUN OF THE ECMWF IS NOW COMING MORE IN LINE
WITH THE GFS IN SWINGING THE NEXT COLD FRONT ACROSS THE AREA ON
TUESDAY...ALTHOUGH THE ECMWF TIMING OF THE FRONT STILL LAGS BEHIND
THE GFS BY AROUND 6 HOURS. HAVE LOWERED TUESDAY HIGHS OVER NERN
WYOMING TO COME MORE IN LINE WITH THE EARLIER FRONTAL PASSAGE.
LOOKS LIKE A CHANCE OF SNOW OVER NERN WY AND FAR WRN SD ON
TUES/TUES NIGHT AS COLDER AIR FLOWS IN BEHIND THE FRONT. THERE IS
A SLIGHT CHANCE OF SNOW OVER SOUTHWESTERN AND SOUTH CENTRAL SOUTH
DAKOTA ON WEDNESDAY AS THOSE AREAS WILL BE ON THE NORTHERN EDGE OF
A BAND OF SNOW ASSOCIATED WITH ISENTROPIC LIFT AHEAD OF AN UPPER
TROUGH MOVING INTO THE CENTRAL PLAINS.

&&

.AVIATION...FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING
ISSUED AT 305 AM MST THU FEB 26 2015

IFR/MVFR CIGS/VSBYS IN -SN OR FLURRIES CURRENTLY LOCATED
OVER THE BLACK HILLS...AND PARTS OF SWRN SD AND NERN WY WILL
CONTINUE TO MOVE OFF TO THE SOUTHWEST THIS MORNING...WITH VFR
CONDITIONS MOVING IN FROM THE NORTHEAST AS DRIER AIR FILTERS IN.
THERE IS A CHANCE OF -SHSN OVER THE BLACK HILLS THIS AFTERNOON WITH
LCL IFR CIGS POSSIBLE IN ANY -SHSN.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...26
LONG TERM...10
AVIATION...10






000
FXUS65 KRIW 260936
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
236 AM MST THU FEB 26 2015

.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT

THE SNOW DISTRIBUTION PATTERN EAST OF THE DIVIDE EARLIER THIS
AFTERNOON WAS AN INTERESTING UPSLOPE/CONVECTIVE SNOW BANDING HYBRID
PATTERN WITH MOIST LOW LEVEL NORTHEAST SFC FLOW AND AN UNSTABLE NW
FLOW A FEW THOUSAND FEET ABOVE THAT AT 700MB. A REINFORCING PUSH OF
COLD AIR WHICH INCREASED THE NORTHEAST WINDS FOR A COUPLE OF HOURS
AROUND SUNSET EARLIER THIS EVENING HAS BLOWN THROUGH WHICH
TEMPORARILY ENHANCED THE SNOW BANDING ACTIVITY...ESPECIALLY IN THE
WIND RIVER BASIN WHERE WIND SPEED CONVERGENCE WAS TAKING PLACE
WHERE THE POST FRONTAL WINDS WERE SLOWING DOWN. CURRENTLY...AN
INTERESTING PHENOMENON IS TAKING PLACE OVER THE WIND RIVER BASIN.
THE SURFACE WINDS HAVE VEERED TO THE EAST BUT THE WINDS AT 700MB
ARE STILL OUT OF THE NORTHWEST. A PERSISTENT AREA OF CONVERGENCE
AT 700MB OR SO ORIGINATING FROM NEAR ANCHOR DAM HAS BEEN STREAMING
SNOW SHOWERS TOWARD THE SOUTHEAST TOWARD RIVERTON ALL EVENING AND
SINCE MIDNIGHT. HOWEVER...THE EAST WINDS ARE CAUSING THE SNOW
SHOWERS TO ENHANCE FROM SOUTHEAST TO NORTHWEST TOWARD CROWHEART
CAUSING THE SNOW SHOWERS TO PROPAGATE BACKWARDS TOWARD THE
NORTHWEST EVEN THOUGH THE INDIVIDUAL SNOW SHOWER ELEMENTS ARE
TRACKING SOUTHEAST. OVERALL...THE REMAINING SNOW BANDS ARE
DWINDLING NOW THAT THE H7 TEMPS ARE DECREASING AND ARE NOW TOO
COLD TO SUPPORT IDEAL DENDRITIC GROWTH.

THEN THE NEXT SHORTWAVE IN THE NORTHWEST FLOW WILL SCOOT ACROSS
NORTHEAST WY THIS EVENING WITH PVA OUT AHEAD OF IT TODAY. THIS WILL
EXPAND THE COVERAGE OF LIGHT SNOW ACROSS AREAS EAST OF THE DIVIDE
TODAY BUT LESS ACCUMULATION IS EXPECTED TODAY THAN ON WEDNESDAY
SINCE LESS MOISTURE WILL BE AVAILABLE ADVECTING IN FROM INTERIOR
CANADA AND JET DYNAMICS WILL BE LACKING. WEST OF THE DIVIDE...ENOUGH
WEAK INSTABILITY SHOULD BE AROUND FOR MORE SNOW SHOWERS THERE. THEN
TONIGHT THE FOCUS OF ANY SNOWFALL WILL PIVOT TO SOUTHWEST WY CLOSER
TO THE SOUTHWESTWARD MOVING SOUTHERN JET ENERGY. ON FRIDAY...SNOWFALL
WILL RETURN TO THE FAR WEST AS THE NEXT TROUGH IN THE PACIFIC
NORTHWEST MOVES SOUTHEAST TOWARD THE GREAT BASIN. THE MODELS HAVE
BEEN WAFFLING WITH THE DYNAMICS OUT AHEAD OF THIS LOW FOR SATURDAY
WITH THE GFS ADVERTISING A BROAD FIELD OF ISENTROPIC LIFT ACROSS
CENTRAL AND SOUTHERN WY SATURDAY BUT NOT THE ECMWF. THEN BOTH MODELS
TOOK ALL THE ENERGY TO THE SOUTH AND EAST OF OUR CWA. NOW THE GFS
WANTS TO PAINT A BROAD AREA OF ISENTROPIC LIFT OVER THE AREA ONCE
AGAIN AND THE ECMWF ONLY SOUTHWEST WY. THIS ISENTROPIC LIFT WOULD
SEED A LOWER DECK OF CLOUDS RESULTING FROM LOW LEVEL UPSLOPE EAST
OF THE DIVIDE. WILL KEEP THE IDEA OF A BROAD AREA OF CHC SNOW
OVER THE CWA EAST AND WEST OF THE DIVIDE FOR SATURDAY FOR NOW. ANY
SNOWFALL WILL END FROM NORTHWEST TO SOUTHEAST SATURDAY NIGHT.

THIS MORNING SHOULD BE THE COLDEST PERIOD FOR SOME LOCATIONS THAT
MANAGE TO CLEAR OUT 24 HOURS AFTER THE 700MB TEMPS BOTTOMED OUT AT
ROUGHLY -23C OVER JOHNSON COUNTY THURSDAY MORNING...THE TYPICAL
RADIATIONAL COOLING SURFACE COLD TEMPERATURE LAG. SEASONABLY COLD
WEATHER CAN BE EXPECTED FOR THE REST OF THE WEEK. THE COLD FRONT
ASCT WITH THIS SATURDAYS WEATHER FEATURE WILL LEAVE BEHIND -17C
700MB AIR OVER NORTH CENTRAL WY BY 12Z SUNDAY RESULTING IN A FEW
MORE BELOW ZERO READINGS BY LATE SATURDAY NIGHT.

.LONG TERM...SUNDAY THROUGH THURSDAY

MODELS IN EXCELLENT AGREEMENT TONIGHT ALTHOUGH THE EURO SLOWS OUR
TUE/WED SYSTEM DOWN AND TRIES TO CLOSE IT OFF NRN UT BRIEFLY EARLY
WED. SATURDAY`S SYSTEM DIGS FURTHER INTO FAR SRN CA WITH MOST OF
THE AREA CLEARING OUT BY THE START OF THE PERIOD. ONLY THE FAR
SOUTH COULD REMAIN ON THE NRN FRINGES OF THIS SYSTEM. CLOUDS IF
NOTHING ELSE WITH A LITTLE POTENTIAL FOR SOME LINGERING SNOW IN
THE FAR SRN SECTIONS. COLD START MONDAY IF THERE`S ENOUGH OF A
BREAK IN CLOUD COVER BEFORE OUR NEXT SYSTEM COMES QUICKLY IN LATER
MONDAY NIGHT THROUGH TUESDAY. THIS SYSTEM ORIGINATES OVER
KAMCHATKA AND COMES IN AT A COLD...HIGH LATITUDE. GFS/EURO IS
BRINGING A FAIRLY SHARP BUT NOT QUITE CLOSED OFF TROUGH INTO THE
GREAT BASIN TUESDAY...HEADING FOR COLORADO BY WEDNESDAY.
INCREASING FORCING AND DECENT LAPSE RATES AHEAD OF THE FRONT
SHOULD GET SOME SNOW GOING AS THIS SYSTEM DROPS SWD. COULD BE A
DECENT PERIOD OF FORCING ACROSS THE AREA WITH DECENT CENTRAL ZONE
UPSLOPE. STILL ALONG WAY AWAY BUT POTENTIAL FOR AT LEAST SOME
HIGHLIGHTS ARE CERTAINLY THERE...AT LEAST WINTER WX ADVISORIES. IF
IT SLOWS DOWN/TRIES TO CLOSE OFF MORE LIKE THE EURO HINTS AT...COULD
BE EVEN MORE INTERESTING. VERY COLD...CYCLONIC FLOW PEAKS ON
WEDNESDAY WITH GFS AND ECMWF SHOWING -24C TO -25C AT H7 IN CENTRAL
WYO. WARMING ALOFT WEDNESDAY NIGHT WHICH MAY RESULT IN SOME FOG IN
THE NORMAL AREAS. INCREASING NW FLOW POSSIBLE BY THURSDAY WITH
SOME INCREASE MOUNTAIN WIND AND POSSIBLY THE WIND CORRIDOR/CODY
FOOTHILLS BUT STILL RATHER CHILLY TEMPS ALOFT.

&&

.AVIATION.../12Z ISSUANCE/

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

VFR TO MVFR CONDITIONS WILL OCCUR TODAY THROUGH 02Z FRIDAY AS AREAS
OF LIGHT SNOW AND LOWER CLOUDS ARE EXPECTED. SOME MOUNTAIN
OBSCURATION AT TIMES THROUGH 02Z FRIDAY. AFTER 02Z VFR CONDITIONS
WILL PREVAIL OVER THE AREA.

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

VFR TO MVFR CONDITIONS WILL OCCUR OVER SOUTHWEST WY TODAY THROUGH
01Z FRIDAY AS AREAS OF LIGHT SNOW AND LOWER CLOUDS ARE EXPECTED.
SOME MOUNTAIN OBSCURATION AT TIMES THROUGH 01Z FRIDAY. AFTER 01Z VFR
CONDITIONS WILL PREVAIL OVER THE REGION.

&&

.FIRE WEATHER...

TODAY WILL FEATURE AREAS OF LIGHT SNOWFALL EAST OF THE DIVIDE
TODAY WITH SOME SNOW SHOWERS WEST WITH NORTHWESTERLY FLOW
CONTINUING. HOWEVER...PINPOINTING EXACTLY WHERE THE SNOW WILL FALL
WILL BE RATHER DIFFICULT. WITH FRESH SNOW COVER IN SOME OF THE
BASINS...TEMPERATURE INVERSIONS WILL BE IN PLACE THIS MORNING RESULTING
IN LOW MIXING HEIGHTS AND POOR SMOKE DISPERSAL. THERE IS A GOOD
CHANCE OF SNOW IN THE WEST FRIDAY...POTENTIALLY SPREADING TO
AREAS EAST OF THE DIVIDE SATURDAY. MORE COLD WEATHER IS EXPECTED
BEHIND SATURDAYS WEATHER FEATURE.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...LIPSON
LONG TERM...PS
AVIATION...AR
FIRE WEATHER...LIPSON











000
FXUS65 KRIW 260936
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
236 AM MST THU FEB 26 2015

.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT

THE SNOW DISTRIBUTION PATTERN EAST OF THE DIVIDE EARLIER THIS
AFTERNOON WAS AN INTERESTING UPSLOPE/CONVECTIVE SNOW BANDING HYBRID
PATTERN WITH MOIST LOW LEVEL NORTHEAST SFC FLOW AND AN UNSTABLE NW
FLOW A FEW THOUSAND FEET ABOVE THAT AT 700MB. A REINFORCING PUSH OF
COLD AIR WHICH INCREASED THE NORTHEAST WINDS FOR A COUPLE OF HOURS
AROUND SUNSET EARLIER THIS EVENING HAS BLOWN THROUGH WHICH
TEMPORARILY ENHANCED THE SNOW BANDING ACTIVITY...ESPECIALLY IN THE
WIND RIVER BASIN WHERE WIND SPEED CONVERGENCE WAS TAKING PLACE
WHERE THE POST FRONTAL WINDS WERE SLOWING DOWN. CURRENTLY...AN
INTERESTING PHENOMENON IS TAKING PLACE OVER THE WIND RIVER BASIN.
THE SURFACE WINDS HAVE VEERED TO THE EAST BUT THE WINDS AT 700MB
ARE STILL OUT OF THE NORTHWEST. A PERSISTENT AREA OF CONVERGENCE
AT 700MB OR SO ORIGINATING FROM NEAR ANCHOR DAM HAS BEEN STREAMING
SNOW SHOWERS TOWARD THE SOUTHEAST TOWARD RIVERTON ALL EVENING AND
SINCE MIDNIGHT. HOWEVER...THE EAST WINDS ARE CAUSING THE SNOW
SHOWERS TO ENHANCE FROM SOUTHEAST TO NORTHWEST TOWARD CROWHEART
CAUSING THE SNOW SHOWERS TO PROPAGATE BACKWARDS TOWARD THE
NORTHWEST EVEN THOUGH THE INDIVIDUAL SNOW SHOWER ELEMENTS ARE
TRACKING SOUTHEAST. OVERALL...THE REMAINING SNOW BANDS ARE
DWINDLING NOW THAT THE H7 TEMPS ARE DECREASING AND ARE NOW TOO
COLD TO SUPPORT IDEAL DENDRITIC GROWTH.

THEN THE NEXT SHORTWAVE IN THE NORTHWEST FLOW WILL SCOOT ACROSS
NORTHEAST WY THIS EVENING WITH PVA OUT AHEAD OF IT TODAY. THIS WILL
EXPAND THE COVERAGE OF LIGHT SNOW ACROSS AREAS EAST OF THE DIVIDE
TODAY BUT LESS ACCUMULATION IS EXPECTED TODAY THAN ON WEDNESDAY
SINCE LESS MOISTURE WILL BE AVAILABLE ADVECTING IN FROM INTERIOR
CANADA AND JET DYNAMICS WILL BE LACKING. WEST OF THE DIVIDE...ENOUGH
WEAK INSTABILITY SHOULD BE AROUND FOR MORE SNOW SHOWERS THERE. THEN
TONIGHT THE FOCUS OF ANY SNOWFALL WILL PIVOT TO SOUTHWEST WY CLOSER
TO THE SOUTHWESTWARD MOVING SOUTHERN JET ENERGY. ON FRIDAY...SNOWFALL
WILL RETURN TO THE FAR WEST AS THE NEXT TROUGH IN THE PACIFIC
NORTHWEST MOVES SOUTHEAST TOWARD THE GREAT BASIN. THE MODELS HAVE
BEEN WAFFLING WITH THE DYNAMICS OUT AHEAD OF THIS LOW FOR SATURDAY
WITH THE GFS ADVERTISING A BROAD FIELD OF ISENTROPIC LIFT ACROSS
CENTRAL AND SOUTHERN WY SATURDAY BUT NOT THE ECMWF. THEN BOTH MODELS
TOOK ALL THE ENERGY TO THE SOUTH AND EAST OF OUR CWA. NOW THE GFS
WANTS TO PAINT A BROAD AREA OF ISENTROPIC LIFT OVER THE AREA ONCE
AGAIN AND THE ECMWF ONLY SOUTHWEST WY. THIS ISENTROPIC LIFT WOULD
SEED A LOWER DECK OF CLOUDS RESULTING FROM LOW LEVEL UPSLOPE EAST
OF THE DIVIDE. WILL KEEP THE IDEA OF A BROAD AREA OF CHC SNOW
OVER THE CWA EAST AND WEST OF THE DIVIDE FOR SATURDAY FOR NOW. ANY
SNOWFALL WILL END FROM NORTHWEST TO SOUTHEAST SATURDAY NIGHT.

THIS MORNING SHOULD BE THE COLDEST PERIOD FOR SOME LOCATIONS THAT
MANAGE TO CLEAR OUT 24 HOURS AFTER THE 700MB TEMPS BOTTOMED OUT AT
ROUGHLY -23C OVER JOHNSON COUNTY THURSDAY MORNING...THE TYPICAL
RADIATIONAL COOLING SURFACE COLD TEMPERATURE LAG. SEASONABLY COLD
WEATHER CAN BE EXPECTED FOR THE REST OF THE WEEK. THE COLD FRONT
ASCT WITH THIS SATURDAYS WEATHER FEATURE WILL LEAVE BEHIND -17C
700MB AIR OVER NORTH CENTRAL WY BY 12Z SUNDAY RESULTING IN A FEW
MORE BELOW ZERO READINGS BY LATE SATURDAY NIGHT.

.LONG TERM...SUNDAY THROUGH THURSDAY

MODELS IN EXCELLENT AGREEMENT TONIGHT ALTHOUGH THE EURO SLOWS OUR
TUE/WED SYSTEM DOWN AND TRIES TO CLOSE IT OFF NRN UT BRIEFLY EARLY
WED. SATURDAY`S SYSTEM DIGS FURTHER INTO FAR SRN CA WITH MOST OF
THE AREA CLEARING OUT BY THE START OF THE PERIOD. ONLY THE FAR
SOUTH COULD REMAIN ON THE NRN FRINGES OF THIS SYSTEM. CLOUDS IF
NOTHING ELSE WITH A LITTLE POTENTIAL FOR SOME LINGERING SNOW IN
THE FAR SRN SECTIONS. COLD START MONDAY IF THERE`S ENOUGH OF A
BREAK IN CLOUD COVER BEFORE OUR NEXT SYSTEM COMES QUICKLY IN LATER
MONDAY NIGHT THROUGH TUESDAY. THIS SYSTEM ORIGINATES OVER
KAMCHATKA AND COMES IN AT A COLD...HIGH LATITUDE. GFS/EURO IS
BRINGING A FAIRLY SHARP BUT NOT QUITE CLOSED OFF TROUGH INTO THE
GREAT BASIN TUESDAY...HEADING FOR COLORADO BY WEDNESDAY.
INCREASING FORCING AND DECENT LAPSE RATES AHEAD OF THE FRONT
SHOULD GET SOME SNOW GOING AS THIS SYSTEM DROPS SWD. COULD BE A
DECENT PERIOD OF FORCING ACROSS THE AREA WITH DECENT CENTRAL ZONE
UPSLOPE. STILL ALONG WAY AWAY BUT POTENTIAL FOR AT LEAST SOME
HIGHLIGHTS ARE CERTAINLY THERE...AT LEAST WINTER WX ADVISORIES. IF
IT SLOWS DOWN/TRIES TO CLOSE OFF MORE LIKE THE EURO HINTS AT...COULD
BE EVEN MORE INTERESTING. VERY COLD...CYCLONIC FLOW PEAKS ON
WEDNESDAY WITH GFS AND ECMWF SHOWING -24C TO -25C AT H7 IN CENTRAL
WYO. WARMING ALOFT WEDNESDAY NIGHT WHICH MAY RESULT IN SOME FOG IN
THE NORMAL AREAS. INCREASING NW FLOW POSSIBLE BY THURSDAY WITH
SOME INCREASE MOUNTAIN WIND AND POSSIBLY THE WIND CORRIDOR/CODY
FOOTHILLS BUT STILL RATHER CHILLY TEMPS ALOFT.

&&

.AVIATION.../12Z ISSUANCE/

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

VFR TO MVFR CONDITIONS WILL OCCUR TODAY THROUGH 02Z FRIDAY AS AREAS
OF LIGHT SNOW AND LOWER CLOUDS ARE EXPECTED. SOME MOUNTAIN
OBSCURATION AT TIMES THROUGH 02Z FRIDAY. AFTER 02Z VFR CONDITIONS
WILL PREVAIL OVER THE AREA.

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

VFR TO MVFR CONDITIONS WILL OCCUR OVER SOUTHWEST WY TODAY THROUGH
01Z FRIDAY AS AREAS OF LIGHT SNOW AND LOWER CLOUDS ARE EXPECTED.
SOME MOUNTAIN OBSCURATION AT TIMES THROUGH 01Z FRIDAY. AFTER 01Z VFR
CONDITIONS WILL PREVAIL OVER THE REGION.

&&

.FIRE WEATHER...

TODAY WILL FEATURE AREAS OF LIGHT SNOWFALL EAST OF THE DIVIDE
TODAY WITH SOME SNOW SHOWERS WEST WITH NORTHWESTERLY FLOW
CONTINUING. HOWEVER...PINPOINTING EXACTLY WHERE THE SNOW WILL FALL
WILL BE RATHER DIFFICULT. WITH FRESH SNOW COVER IN SOME OF THE
BASINS...TEMPERATURE INVERSIONS WILL BE IN PLACE THIS MORNING RESULTING
IN LOW MIXING HEIGHTS AND POOR SMOKE DISPERSAL. THERE IS A GOOD
CHANCE OF SNOW IN THE WEST FRIDAY...POTENTIALLY SPREADING TO
AREAS EAST OF THE DIVIDE SATURDAY. MORE COLD WEATHER IS EXPECTED
BEHIND SATURDAYS WEATHER FEATURE.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...LIPSON
LONG TERM...PS
AVIATION...AR
FIRE WEATHER...LIPSON












000
FXUS65 KRIW 260936
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
236 AM MST THU FEB 26 2015

.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT

THE SNOW DISTRIBUTION PATTERN EAST OF THE DIVIDE EARLIER THIS
AFTERNOON WAS AN INTERESTING UPSLOPE/CONVECTIVE SNOW BANDING HYBRID
PATTERN WITH MOIST LOW LEVEL NORTHEAST SFC FLOW AND AN UNSTABLE NW
FLOW A FEW THOUSAND FEET ABOVE THAT AT 700MB. A REINFORCING PUSH OF
COLD AIR WHICH INCREASED THE NORTHEAST WINDS FOR A COUPLE OF HOURS
AROUND SUNSET EARLIER THIS EVENING HAS BLOWN THROUGH WHICH
TEMPORARILY ENHANCED THE SNOW BANDING ACTIVITY...ESPECIALLY IN THE
WIND RIVER BASIN WHERE WIND SPEED CONVERGENCE WAS TAKING PLACE
WHERE THE POST FRONTAL WINDS WERE SLOWING DOWN. CURRENTLY...AN
INTERESTING PHENOMENON IS TAKING PLACE OVER THE WIND RIVER BASIN.
THE SURFACE WINDS HAVE VEERED TO THE EAST BUT THE WINDS AT 700MB
ARE STILL OUT OF THE NORTHWEST. A PERSISTENT AREA OF CONVERGENCE
AT 700MB OR SO ORIGINATING FROM NEAR ANCHOR DAM HAS BEEN STREAMING
SNOW SHOWERS TOWARD THE SOUTHEAST TOWARD RIVERTON ALL EVENING AND
SINCE MIDNIGHT. HOWEVER...THE EAST WINDS ARE CAUSING THE SNOW
SHOWERS TO ENHANCE FROM SOUTHEAST TO NORTHWEST TOWARD CROWHEART
CAUSING THE SNOW SHOWERS TO PROPAGATE BACKWARDS TOWARD THE
NORTHWEST EVEN THOUGH THE INDIVIDUAL SNOW SHOWER ELEMENTS ARE
TRACKING SOUTHEAST. OVERALL...THE REMAINING SNOW BANDS ARE
DWINDLING NOW THAT THE H7 TEMPS ARE DECREASING AND ARE NOW TOO
COLD TO SUPPORT IDEAL DENDRITIC GROWTH.

THEN THE NEXT SHORTWAVE IN THE NORTHWEST FLOW WILL SCOOT ACROSS
NORTHEAST WY THIS EVENING WITH PVA OUT AHEAD OF IT TODAY. THIS WILL
EXPAND THE COVERAGE OF LIGHT SNOW ACROSS AREAS EAST OF THE DIVIDE
TODAY BUT LESS ACCUMULATION IS EXPECTED TODAY THAN ON WEDNESDAY
SINCE LESS MOISTURE WILL BE AVAILABLE ADVECTING IN FROM INTERIOR
CANADA AND JET DYNAMICS WILL BE LACKING. WEST OF THE DIVIDE...ENOUGH
WEAK INSTABILITY SHOULD BE AROUND FOR MORE SNOW SHOWERS THERE. THEN
TONIGHT THE FOCUS OF ANY SNOWFALL WILL PIVOT TO SOUTHWEST WY CLOSER
TO THE SOUTHWESTWARD MOVING SOUTHERN JET ENERGY. ON FRIDAY...SNOWFALL
WILL RETURN TO THE FAR WEST AS THE NEXT TROUGH IN THE PACIFIC
NORTHWEST MOVES SOUTHEAST TOWARD THE GREAT BASIN. THE MODELS HAVE
BEEN WAFFLING WITH THE DYNAMICS OUT AHEAD OF THIS LOW FOR SATURDAY
WITH THE GFS ADVERTISING A BROAD FIELD OF ISENTROPIC LIFT ACROSS
CENTRAL AND SOUTHERN WY SATURDAY BUT NOT THE ECMWF. THEN BOTH MODELS
TOOK ALL THE ENERGY TO THE SOUTH AND EAST OF OUR CWA. NOW THE GFS
WANTS TO PAINT A BROAD AREA OF ISENTROPIC LIFT OVER THE AREA ONCE
AGAIN AND THE ECMWF ONLY SOUTHWEST WY. THIS ISENTROPIC LIFT WOULD
SEED A LOWER DECK OF CLOUDS RESULTING FROM LOW LEVEL UPSLOPE EAST
OF THE DIVIDE. WILL KEEP THE IDEA OF A BROAD AREA OF CHC SNOW
OVER THE CWA EAST AND WEST OF THE DIVIDE FOR SATURDAY FOR NOW. ANY
SNOWFALL WILL END FROM NORTHWEST TO SOUTHEAST SATURDAY NIGHT.

THIS MORNING SHOULD BE THE COLDEST PERIOD FOR SOME LOCATIONS THAT
MANAGE TO CLEAR OUT 24 HOURS AFTER THE 700MB TEMPS BOTTOMED OUT AT
ROUGHLY -23C OVER JOHNSON COUNTY THURSDAY MORNING...THE TYPICAL
RADIATIONAL COOLING SURFACE COLD TEMPERATURE LAG. SEASONABLY COLD
WEATHER CAN BE EXPECTED FOR THE REST OF THE WEEK. THE COLD FRONT
ASCT WITH THIS SATURDAYS WEATHER FEATURE WILL LEAVE BEHIND -17C
700MB AIR OVER NORTH CENTRAL WY BY 12Z SUNDAY RESULTING IN A FEW
MORE BELOW ZERO READINGS BY LATE SATURDAY NIGHT.

.LONG TERM...SUNDAY THROUGH THURSDAY

MODELS IN EXCELLENT AGREEMENT TONIGHT ALTHOUGH THE EURO SLOWS OUR
TUE/WED SYSTEM DOWN AND TRIES TO CLOSE IT OFF NRN UT BRIEFLY EARLY
WED. SATURDAY`S SYSTEM DIGS FURTHER INTO FAR SRN CA WITH MOST OF
THE AREA CLEARING OUT BY THE START OF THE PERIOD. ONLY THE FAR
SOUTH COULD REMAIN ON THE NRN FRINGES OF THIS SYSTEM. CLOUDS IF
NOTHING ELSE WITH A LITTLE POTENTIAL FOR SOME LINGERING SNOW IN
THE FAR SRN SECTIONS. COLD START MONDAY IF THERE`S ENOUGH OF A
BREAK IN CLOUD COVER BEFORE OUR NEXT SYSTEM COMES QUICKLY IN LATER
MONDAY NIGHT THROUGH TUESDAY. THIS SYSTEM ORIGINATES OVER
KAMCHATKA AND COMES IN AT A COLD...HIGH LATITUDE. GFS/EURO IS
BRINGING A FAIRLY SHARP BUT NOT QUITE CLOSED OFF TROUGH INTO THE
GREAT BASIN TUESDAY...HEADING FOR COLORADO BY WEDNESDAY.
INCREASING FORCING AND DECENT LAPSE RATES AHEAD OF THE FRONT
SHOULD GET SOME SNOW GOING AS THIS SYSTEM DROPS SWD. COULD BE A
DECENT PERIOD OF FORCING ACROSS THE AREA WITH DECENT CENTRAL ZONE
UPSLOPE. STILL ALONG WAY AWAY BUT POTENTIAL FOR AT LEAST SOME
HIGHLIGHTS ARE CERTAINLY THERE...AT LEAST WINTER WX ADVISORIES. IF
IT SLOWS DOWN/TRIES TO CLOSE OFF MORE LIKE THE EURO HINTS AT...COULD
BE EVEN MORE INTERESTING. VERY COLD...CYCLONIC FLOW PEAKS ON
WEDNESDAY WITH GFS AND ECMWF SHOWING -24C TO -25C AT H7 IN CENTRAL
WYO. WARMING ALOFT WEDNESDAY NIGHT WHICH MAY RESULT IN SOME FOG IN
THE NORMAL AREAS. INCREASING NW FLOW POSSIBLE BY THURSDAY WITH
SOME INCREASE MOUNTAIN WIND AND POSSIBLY THE WIND CORRIDOR/CODY
FOOTHILLS BUT STILL RATHER CHILLY TEMPS ALOFT.

&&

.AVIATION.../12Z ISSUANCE/

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

VFR TO MVFR CONDITIONS WILL OCCUR TODAY THROUGH 02Z FRIDAY AS AREAS
OF LIGHT SNOW AND LOWER CLOUDS ARE EXPECTED. SOME MOUNTAIN
OBSCURATION AT TIMES THROUGH 02Z FRIDAY. AFTER 02Z VFR CONDITIONS
WILL PREVAIL OVER THE AREA.

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

VFR TO MVFR CONDITIONS WILL OCCUR OVER SOUTHWEST WY TODAY THROUGH
01Z FRIDAY AS AREAS OF LIGHT SNOW AND LOWER CLOUDS ARE EXPECTED.
SOME MOUNTAIN OBSCURATION AT TIMES THROUGH 01Z FRIDAY. AFTER 01Z VFR
CONDITIONS WILL PREVAIL OVER THE REGION.

&&

.FIRE WEATHER...

TODAY WILL FEATURE AREAS OF LIGHT SNOWFALL EAST OF THE DIVIDE
TODAY WITH SOME SNOW SHOWERS WEST WITH NORTHWESTERLY FLOW
CONTINUING. HOWEVER...PINPOINTING EXACTLY WHERE THE SNOW WILL FALL
WILL BE RATHER DIFFICULT. WITH FRESH SNOW COVER IN SOME OF THE
BASINS...TEMPERATURE INVERSIONS WILL BE IN PLACE THIS MORNING RESULTING
IN LOW MIXING HEIGHTS AND POOR SMOKE DISPERSAL. THERE IS A GOOD
CHANCE OF SNOW IN THE WEST FRIDAY...POTENTIALLY SPREADING TO
AREAS EAST OF THE DIVIDE SATURDAY. MORE COLD WEATHER IS EXPECTED
BEHIND SATURDAYS WEATHER FEATURE.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...LIPSON
LONG TERM...PS
AVIATION...AR
FIRE WEATHER...LIPSON












000
FXUS65 KRIW 260936
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
236 AM MST THU FEB 26 2015

.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT

THE SNOW DISTRIBUTION PATTERN EAST OF THE DIVIDE EARLIER THIS
AFTERNOON WAS AN INTERESTING UPSLOPE/CONVECTIVE SNOW BANDING HYBRID
PATTERN WITH MOIST LOW LEVEL NORTHEAST SFC FLOW AND AN UNSTABLE NW
FLOW A FEW THOUSAND FEET ABOVE THAT AT 700MB. A REINFORCING PUSH OF
COLD AIR WHICH INCREASED THE NORTHEAST WINDS FOR A COUPLE OF HOURS
AROUND SUNSET EARLIER THIS EVENING HAS BLOWN THROUGH WHICH
TEMPORARILY ENHANCED THE SNOW BANDING ACTIVITY...ESPECIALLY IN THE
WIND RIVER BASIN WHERE WIND SPEED CONVERGENCE WAS TAKING PLACE
WHERE THE POST FRONTAL WINDS WERE SLOWING DOWN. CURRENTLY...AN
INTERESTING PHENOMENON IS TAKING PLACE OVER THE WIND RIVER BASIN.
THE SURFACE WINDS HAVE VEERED TO THE EAST BUT THE WINDS AT 700MB
ARE STILL OUT OF THE NORTHWEST. A PERSISTENT AREA OF CONVERGENCE
AT 700MB OR SO ORIGINATING FROM NEAR ANCHOR DAM HAS BEEN STREAMING
SNOW SHOWERS TOWARD THE SOUTHEAST TOWARD RIVERTON ALL EVENING AND
SINCE MIDNIGHT. HOWEVER...THE EAST WINDS ARE CAUSING THE SNOW
SHOWERS TO ENHANCE FROM SOUTHEAST TO NORTHWEST TOWARD CROWHEART
CAUSING THE SNOW SHOWERS TO PROPAGATE BACKWARDS TOWARD THE
NORTHWEST EVEN THOUGH THE INDIVIDUAL SNOW SHOWER ELEMENTS ARE
TRACKING SOUTHEAST. OVERALL...THE REMAINING SNOW BANDS ARE
DWINDLING NOW THAT THE H7 TEMPS ARE DECREASING AND ARE NOW TOO
COLD TO SUPPORT IDEAL DENDRITIC GROWTH.

THEN THE NEXT SHORTWAVE IN THE NORTHWEST FLOW WILL SCOOT ACROSS
NORTHEAST WY THIS EVENING WITH PVA OUT AHEAD OF IT TODAY. THIS WILL
EXPAND THE COVERAGE OF LIGHT SNOW ACROSS AREAS EAST OF THE DIVIDE
TODAY BUT LESS ACCUMULATION IS EXPECTED TODAY THAN ON WEDNESDAY
SINCE LESS MOISTURE WILL BE AVAILABLE ADVECTING IN FROM INTERIOR
CANADA AND JET DYNAMICS WILL BE LACKING. WEST OF THE DIVIDE...ENOUGH
WEAK INSTABILITY SHOULD BE AROUND FOR MORE SNOW SHOWERS THERE. THEN
TONIGHT THE FOCUS OF ANY SNOWFALL WILL PIVOT TO SOUTHWEST WY CLOSER
TO THE SOUTHWESTWARD MOVING SOUTHERN JET ENERGY. ON FRIDAY...SNOWFALL
WILL RETURN TO THE FAR WEST AS THE NEXT TROUGH IN THE PACIFIC
NORTHWEST MOVES SOUTHEAST TOWARD THE GREAT BASIN. THE MODELS HAVE
BEEN WAFFLING WITH THE DYNAMICS OUT AHEAD OF THIS LOW FOR SATURDAY
WITH THE GFS ADVERTISING A BROAD FIELD OF ISENTROPIC LIFT ACROSS
CENTRAL AND SOUTHERN WY SATURDAY BUT NOT THE ECMWF. THEN BOTH MODELS
TOOK ALL THE ENERGY TO THE SOUTH AND EAST OF OUR CWA. NOW THE GFS
WANTS TO PAINT A BROAD AREA OF ISENTROPIC LIFT OVER THE AREA ONCE
AGAIN AND THE ECMWF ONLY SOUTHWEST WY. THIS ISENTROPIC LIFT WOULD
SEED A LOWER DECK OF CLOUDS RESULTING FROM LOW LEVEL UPSLOPE EAST
OF THE DIVIDE. WILL KEEP THE IDEA OF A BROAD AREA OF CHC SNOW
OVER THE CWA EAST AND WEST OF THE DIVIDE FOR SATURDAY FOR NOW. ANY
SNOWFALL WILL END FROM NORTHWEST TO SOUTHEAST SATURDAY NIGHT.

THIS MORNING SHOULD BE THE COLDEST PERIOD FOR SOME LOCATIONS THAT
MANAGE TO CLEAR OUT 24 HOURS AFTER THE 700MB TEMPS BOTTOMED OUT AT
ROUGHLY -23C OVER JOHNSON COUNTY THURSDAY MORNING...THE TYPICAL
RADIATIONAL COOLING SURFACE COLD TEMPERATURE LAG. SEASONABLY COLD
WEATHER CAN BE EXPECTED FOR THE REST OF THE WEEK. THE COLD FRONT
ASCT WITH THIS SATURDAYS WEATHER FEATURE WILL LEAVE BEHIND -17C
700MB AIR OVER NORTH CENTRAL WY BY 12Z SUNDAY RESULTING IN A FEW
MORE BELOW ZERO READINGS BY LATE SATURDAY NIGHT.

.LONG TERM...SUNDAY THROUGH THURSDAY

MODELS IN EXCELLENT AGREEMENT TONIGHT ALTHOUGH THE EURO SLOWS OUR
TUE/WED SYSTEM DOWN AND TRIES TO CLOSE IT OFF NRN UT BRIEFLY EARLY
WED. SATURDAY`S SYSTEM DIGS FURTHER INTO FAR SRN CA WITH MOST OF
THE AREA CLEARING OUT BY THE START OF THE PERIOD. ONLY THE FAR
SOUTH COULD REMAIN ON THE NRN FRINGES OF THIS SYSTEM. CLOUDS IF
NOTHING ELSE WITH A LITTLE POTENTIAL FOR SOME LINGERING SNOW IN
THE FAR SRN SECTIONS. COLD START MONDAY IF THERE`S ENOUGH OF A
BREAK IN CLOUD COVER BEFORE OUR NEXT SYSTEM COMES QUICKLY IN LATER
MONDAY NIGHT THROUGH TUESDAY. THIS SYSTEM ORIGINATES OVER
KAMCHATKA AND COMES IN AT A COLD...HIGH LATITUDE. GFS/EURO IS
BRINGING A FAIRLY SHARP BUT NOT QUITE CLOSED OFF TROUGH INTO THE
GREAT BASIN TUESDAY...HEADING FOR COLORADO BY WEDNESDAY.
INCREASING FORCING AND DECENT LAPSE RATES AHEAD OF THE FRONT
SHOULD GET SOME SNOW GOING AS THIS SYSTEM DROPS SWD. COULD BE A
DECENT PERIOD OF FORCING ACROSS THE AREA WITH DECENT CENTRAL ZONE
UPSLOPE. STILL ALONG WAY AWAY BUT POTENTIAL FOR AT LEAST SOME
HIGHLIGHTS ARE CERTAINLY THERE...AT LEAST WINTER WX ADVISORIES. IF
IT SLOWS DOWN/TRIES TO CLOSE OFF MORE LIKE THE EURO HINTS AT...COULD
BE EVEN MORE INTERESTING. VERY COLD...CYCLONIC FLOW PEAKS ON
WEDNESDAY WITH GFS AND ECMWF SHOWING -24C TO -25C AT H7 IN CENTRAL
WYO. WARMING ALOFT WEDNESDAY NIGHT WHICH MAY RESULT IN SOME FOG IN
THE NORMAL AREAS. INCREASING NW FLOW POSSIBLE BY THURSDAY WITH
SOME INCREASE MOUNTAIN WIND AND POSSIBLY THE WIND CORRIDOR/CODY
FOOTHILLS BUT STILL RATHER CHILLY TEMPS ALOFT.

&&

.AVIATION.../12Z ISSUANCE/

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

VFR TO MVFR CONDITIONS WILL OCCUR TODAY THROUGH 02Z FRIDAY AS AREAS
OF LIGHT SNOW AND LOWER CLOUDS ARE EXPECTED. SOME MOUNTAIN
OBSCURATION AT TIMES THROUGH 02Z FRIDAY. AFTER 02Z VFR CONDITIONS
WILL PREVAIL OVER THE AREA.

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

VFR TO MVFR CONDITIONS WILL OCCUR OVER SOUTHWEST WY TODAY THROUGH
01Z FRIDAY AS AREAS OF LIGHT SNOW AND LOWER CLOUDS ARE EXPECTED.
SOME MOUNTAIN OBSCURATION AT TIMES THROUGH 01Z FRIDAY. AFTER 01Z VFR
CONDITIONS WILL PREVAIL OVER THE REGION.

&&

.FIRE WEATHER...

TODAY WILL FEATURE AREAS OF LIGHT SNOWFALL EAST OF THE DIVIDE
TODAY WITH SOME SNOW SHOWERS WEST WITH NORTHWESTERLY FLOW
CONTINUING. HOWEVER...PINPOINTING EXACTLY WHERE THE SNOW WILL FALL
WILL BE RATHER DIFFICULT. WITH FRESH SNOW COVER IN SOME OF THE
BASINS...TEMPERATURE INVERSIONS WILL BE IN PLACE THIS MORNING RESULTING
IN LOW MIXING HEIGHTS AND POOR SMOKE DISPERSAL. THERE IS A GOOD
CHANCE OF SNOW IN THE WEST FRIDAY...POTENTIALLY SPREADING TO
AREAS EAST OF THE DIVIDE SATURDAY. MORE COLD WEATHER IS EXPECTED
BEHIND SATURDAYS WEATHER FEATURE.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...LIPSON
LONG TERM...PS
AVIATION...AR
FIRE WEATHER...LIPSON











000
FXUS65 KRIW 260547
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1047 PM MST WED FEB 25 2015

.SHORT TERM...TONIGHT THROUGH THURSDAY (ISSUED AT 228 PM MDT)

AN ACTIVE DAY TODAY AS A COLD FRONT HAS MOVED ACROSS THE STATE AND
SOME SNOW HAS BEEN ONGOING. OF COURSE...ONE OF THOSE ANNOYING...PAIN
IN THE BUTT...IMPOSSIBLE TO PREDICT SNOW BANDS HAS DEVELOPED ACROSS
THE WIND RIVER BASIN. THE NAM IS DOING A REASONABLE JOB WITH THIS
TODAY THROUGH. IT SHOWS A GENERAL SLOW SOUTHWESTWARD DRIFT OF THE
BAND THROUGH THE AFTERNOON AND INTO THE EVENING HOURS.
ELSEWHERE...OTHER THAN BUFFALO AND PORTIONS OF THE BIG HORN RANGE
THE SNOW HAS BEEN FAIRLY SPARSE. SOME PERIODS OF SNOW SHOULD
CONTINUE INTO THE EVENING WITH SOME UPPER LEVEL SUPPORT FROM THE
LEFT FRONT QUADRANT OF A JET STREAK MOVING ACROSS THE AREA. WE
THROUGH ABOUT AN ADVISORY FOR THE LANDER FOOTHILLS BUT THE RADAR
TRENDS HAVE BEEN DECREASING OVER THE PAST 30 MINUTES SO WE WILL
STICK TO AN SPS AT THIS TIME. WITH UNSTABLE NORTHWEST FLOW SOME SNOW
SHOWERS WILL CONTINUE THROUGH THE NIGHT ALTHOUGH THE COVERAGE
SHOULD DECREASE AS WE HEAD INTO THE EVENING. AS FOR THE
ADVISORIES...THERE WAS ACTUALLY A BREAK BUT ANOTHER BATCH IS ON
THE WAY. FOR NOW...WE WILL PROBABLY LET THEM RIDE INTO THE EVENING
UNLESS OUR NEIGHBORS HAVE ANY DISAGREEMENTS. WE STILL FEEL THERE
COULD BE A PROBLEM WITH INTERSTATE 80 AS THE BAND MOVES SOUTHWARD
ACROSS SWEETWATER COUNTY AS WELL.

AS FOR TOMORROW...IT LOOKS TO BE SOMEWHAT LESS ACTIVE ALTHOUGH STILL
COLD AND UNSETTLED. WITH UNSTABLE NORTHWEST FLOW CONTINUING OVER THE
AREA AS WELL AS CYCLONIC CURVATURE REMAINING...WE HAVE CONTINUED THE
CHANCE OF SNOW SHOWERS ACROSS PORTIONS OF THE AREA. ONCE
AGAIN...PINPOINTING THEM AT THIS POINT IS NEARLY IMPOSSIBLE...BUT
MANY AREAS WILL HAVE A CHANCE. WITH FRESH SNOW COVER MANY AREAS WILL
STRUGGLE TO GET ABOVE FREEZING.

.LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY

SOME SNOW WILL LINGER OVER THE MOUNTAINS AND SOUTH WITH
CLEARING IN THE NORTH SPREADING SOUTH THROUGH THE NIGHT.
TEMPERATURES WILL BECOME QUITE COLD AGAIN AS VERY COLD CANADIAN
AIR MOVES IN AND COMBINES WITH STRONG RADIATIONAL COOLING.
FRIDAY A PACIFIC TROUGH MOVING RAPIDLY INLAND WILL START BRINGING
AREAS OF SNOW TO THE WEST WITH BREEZY TO WINDY AREAS EAST OF THE
CONTINENTAL DIVIDE.  TEMPERATURES WILL BEGIN TO WARM WITH DOWNSLOPE
WINDS OVER AND NEAR THE EAST SLOPES OF THE MOUNTAINS.  A CANADIAN
COLD FRONT WILL MOVE SOUTH BEHIND THE PACIFIC TROUGH FRIDAY NIGHT
AND SATURDAY WITH MORE AREAS OF SNOW DEVELOPING EAST OF THE
CONTINENTAL DIVIDE WHILE REMAINING OVER THE WESTERN MOUNTAINS.
THIS COLD FRONT WILL SWEEP SOUTH SATURDAY NIGHT WITH DRYING MOVING
INTO THE NORTH ON SUNDAY.  AGAIN VERY COLD AIR WILL INTRUDE FROM THE
NORTH.  SUNDAY NIGHT WILL BE COLD WITH CLEARING. THEN YET ANOTHER
PACIFIC TROUGH WILL RACE EAST MONDAY WITH SNOW MOVING BACK INTO THE
WEST AND WINDS INCREASING EAST OF THE CONTINENTAL DIVIDE WITH
DOWNSLOPE WARMING RETURNING...ONLY TO BE FOLLOWED BY ANOTHER CANADIAN
COLD FRONT MONDAY NIGHT AND TUESDAY SPREADING AREAS OF SNOW ACROSS
THE AREA EAST OF THE CONTINENTAL DIVIDE.  SNOW WILL BE RATHER
WIDESPREAD TUESDAY NIGHT WITH CLEARING ON WEDNESDAY WITH MORE COLD
CANADIAN AIR MOVING IN.  A VERY PROGRESSIVE PATTERN IS IN STORE WITH
TIMING ISSUES LIKELY THROUGH THE PERIOD...INCREASING SIGNIFICANTLY
WITH TIME.

&&

.AVIATION.../06Z ISSUANCE/

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

MVFR TO IFR CONDITIONS WILL OCCUR AT SOME TERMINAL SITES OVERNIGHT
THROUGH THURSDAY AFTERNOON. AREAS OF LIGHT SNOW WILL OCCUR AS WELL
THROUGH 00Z FRIDAY. EXPECT MOUNTAIN OBSCURATION AT TIMES THROUGH 00Z
FRIDAY. AFTER 00Z FRIDAY VFR CONDITIONS WILL PREVAIL OVER THE AREA.
HOWEVER LOCAL MVFR CONDITIONS WILL BE POSSIBLE DUE TO LOW CLOUDS
THROUGH 06Z FRI.

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

VFR TO MVFR CONDITIONS WILL OCCUR OVER SOUTHWEST WY OVERNIGHT
THROUGH THURSDAY AFTERNOON. AREAS OF LIGHT SNOW WILL ALSO OCCUR
THROUGH 00Z FRIDAY. EXPECT MOUNTAIN OBSCURATION AT TIMES THROUGH 00Z
FRIDAY. AFTER 00Z FRIDAY VFR CONDITIONS WILL PREVAIL OVER THE REGION.

&&

.FIRE WEATHER...

OCCASIONAL SNOW WILL CONTINUE INTO TONIGHT ALTHOUGH COVERAGE WILL
SHRINK INTO THE NIGHT GUSTY NORTH TO NORTHEASTERLY WINDS WILL ALSO
GRADUALLY DECREASE INTO THE NIGHT. A CHANCE OF SNOW SHOWERS WILL
LINGER INTO TOMORROW AS WELL WITH UNSTABLE NORTHWESTERLY FLOW
CONTINUING. HOWEVER...PINPOINTING THEM IS VERY DIFFICULT. WITH FRESH
SNOW COVER IN SOME OF THE BASINS INVERSIONS MAY FORM TONIGHT AND
INTO TOMORROW RESULTING IN LOW MIXING HEIGHTS AND POOR SMOKE
DISPERSAL.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

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








000
FXUS65 KRIW 260547
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1047 PM MST WED FEB 25 2015

.SHORT TERM...TONIGHT THROUGH THURSDAY (ISSUED AT 228 PM MDT)

AN ACTIVE DAY TODAY AS A COLD FRONT HAS MOVED ACROSS THE STATE AND
SOME SNOW HAS BEEN ONGOING. OF COURSE...ONE OF THOSE ANNOYING...PAIN
IN THE BUTT...IMPOSSIBLE TO PREDICT SNOW BANDS HAS DEVELOPED ACROSS
THE WIND RIVER BASIN. THE NAM IS DOING A REASONABLE JOB WITH THIS
TODAY THROUGH. IT SHOWS A GENERAL SLOW SOUTHWESTWARD DRIFT OF THE
BAND THROUGH THE AFTERNOON AND INTO THE EVENING HOURS.
ELSEWHERE...OTHER THAN BUFFALO AND PORTIONS OF THE BIG HORN RANGE
THE SNOW HAS BEEN FAIRLY SPARSE. SOME PERIODS OF SNOW SHOULD
CONTINUE INTO THE EVENING WITH SOME UPPER LEVEL SUPPORT FROM THE
LEFT FRONT QUADRANT OF A JET STREAK MOVING ACROSS THE AREA. WE
THROUGH ABOUT AN ADVISORY FOR THE LANDER FOOTHILLS BUT THE RADAR
TRENDS HAVE BEEN DECREASING OVER THE PAST 30 MINUTES SO WE WILL
STICK TO AN SPS AT THIS TIME. WITH UNSTABLE NORTHWEST FLOW SOME SNOW
SHOWERS WILL CONTINUE THROUGH THE NIGHT ALTHOUGH THE COVERAGE
SHOULD DECREASE AS WE HEAD INTO THE EVENING. AS FOR THE
ADVISORIES...THERE WAS ACTUALLY A BREAK BUT ANOTHER BATCH IS ON
THE WAY. FOR NOW...WE WILL PROBABLY LET THEM RIDE INTO THE EVENING
UNLESS OUR NEIGHBORS HAVE ANY DISAGREEMENTS. WE STILL FEEL THERE
COULD BE A PROBLEM WITH INTERSTATE 80 AS THE BAND MOVES SOUTHWARD
ACROSS SWEETWATER COUNTY AS WELL.

AS FOR TOMORROW...IT LOOKS TO BE SOMEWHAT LESS ACTIVE ALTHOUGH STILL
COLD AND UNSETTLED. WITH UNSTABLE NORTHWEST FLOW CONTINUING OVER THE
AREA AS WELL AS CYCLONIC CURVATURE REMAINING...WE HAVE CONTINUED THE
CHANCE OF SNOW SHOWERS ACROSS PORTIONS OF THE AREA. ONCE
AGAIN...PINPOINTING THEM AT THIS POINT IS NEARLY IMPOSSIBLE...BUT
MANY AREAS WILL HAVE A CHANCE. WITH FRESH SNOW COVER MANY AREAS WILL
STRUGGLE TO GET ABOVE FREEZING.

.LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY

SOME SNOW WILL LINGER OVER THE MOUNTAINS AND SOUTH WITH
CLEARING IN THE NORTH SPREADING SOUTH THROUGH THE NIGHT.
TEMPERATURES WILL BECOME QUITE COLD AGAIN AS VERY COLD CANADIAN
AIR MOVES IN AND COMBINES WITH STRONG RADIATIONAL COOLING.
FRIDAY A PACIFIC TROUGH MOVING RAPIDLY INLAND WILL START BRINGING
AREAS OF SNOW TO THE WEST WITH BREEZY TO WINDY AREAS EAST OF THE
CONTINENTAL DIVIDE.  TEMPERATURES WILL BEGIN TO WARM WITH DOWNSLOPE
WINDS OVER AND NEAR THE EAST SLOPES OF THE MOUNTAINS.  A CANADIAN
COLD FRONT WILL MOVE SOUTH BEHIND THE PACIFIC TROUGH FRIDAY NIGHT
AND SATURDAY WITH MORE AREAS OF SNOW DEVELOPING EAST OF THE
CONTINENTAL DIVIDE WHILE REMAINING OVER THE WESTERN MOUNTAINS.
THIS COLD FRONT WILL SWEEP SOUTH SATURDAY NIGHT WITH DRYING MOVING
INTO THE NORTH ON SUNDAY.  AGAIN VERY COLD AIR WILL INTRUDE FROM THE
NORTH.  SUNDAY NIGHT WILL BE COLD WITH CLEARING. THEN YET ANOTHER
PACIFIC TROUGH WILL RACE EAST MONDAY WITH SNOW MOVING BACK INTO THE
WEST AND WINDS INCREASING EAST OF THE CONTINENTAL DIVIDE WITH
DOWNSLOPE WARMING RETURNING...ONLY TO BE FOLLOWED BY ANOTHER CANADIAN
COLD FRONT MONDAY NIGHT AND TUESDAY SPREADING AREAS OF SNOW ACROSS
THE AREA EAST OF THE CONTINENTAL DIVIDE.  SNOW WILL BE RATHER
WIDESPREAD TUESDAY NIGHT WITH CLEARING ON WEDNESDAY WITH MORE COLD
CANADIAN AIR MOVING IN.  A VERY PROGRESSIVE PATTERN IS IN STORE WITH
TIMING ISSUES LIKELY THROUGH THE PERIOD...INCREASING SIGNIFICANTLY
WITH TIME.

&&

.AVIATION.../06Z ISSUANCE/

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

MVFR TO IFR CONDITIONS WILL OCCUR AT SOME TERMINAL SITES OVERNIGHT
THROUGH THURSDAY AFTERNOON. AREAS OF LIGHT SNOW WILL OCCUR AS WELL
THROUGH 00Z FRIDAY. EXPECT MOUNTAIN OBSCURATION AT TIMES THROUGH 00Z
FRIDAY. AFTER 00Z FRIDAY VFR CONDITIONS WILL PREVAIL OVER THE AREA.
HOWEVER LOCAL MVFR CONDITIONS WILL BE POSSIBLE DUE TO LOW CLOUDS
THROUGH 06Z FRI.

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

VFR TO MVFR CONDITIONS WILL OCCUR OVER SOUTHWEST WY OVERNIGHT
THROUGH THURSDAY AFTERNOON. AREAS OF LIGHT SNOW WILL ALSO OCCUR
THROUGH 00Z FRIDAY. EXPECT MOUNTAIN OBSCURATION AT TIMES THROUGH 00Z
FRIDAY. AFTER 00Z FRIDAY VFR CONDITIONS WILL PREVAIL OVER THE REGION.

&&

.FIRE WEATHER...

OCCASIONAL SNOW WILL CONTINUE INTO TONIGHT ALTHOUGH COVERAGE WILL
SHRINK INTO THE NIGHT GUSTY NORTH TO NORTHEASTERLY WINDS WILL ALSO
GRADUALLY DECREASE INTO THE NIGHT. A CHANCE OF SNOW SHOWERS WILL
LINGER INTO TOMORROW AS WELL WITH UNSTABLE NORTHWESTERLY FLOW
CONTINUING. HOWEVER...PINPOINTING THEM IS VERY DIFFICULT. WITH FRESH
SNOW COVER IN SOME OF THE BASINS INVERSIONS MAY FORM TONIGHT AND
INTO TOMORROW RESULTING IN LOW MIXING HEIGHTS AND POOR SMOKE
DISPERSAL.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

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








000
FXUS65 KRIW 260547
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1047 PM MST WED FEB 25 2015

.SHORT TERM...TONIGHT THROUGH THURSDAY (ISSUED AT 228 PM MDT)

AN ACTIVE DAY TODAY AS A COLD FRONT HAS MOVED ACROSS THE STATE AND
SOME SNOW HAS BEEN ONGOING. OF COURSE...ONE OF THOSE ANNOYING...PAIN
IN THE BUTT...IMPOSSIBLE TO PREDICT SNOW BANDS HAS DEVELOPED ACROSS
THE WIND RIVER BASIN. THE NAM IS DOING A REASONABLE JOB WITH THIS
TODAY THROUGH. IT SHOWS A GENERAL SLOW SOUTHWESTWARD DRIFT OF THE
BAND THROUGH THE AFTERNOON AND INTO THE EVENING HOURS.
ELSEWHERE...OTHER THAN BUFFALO AND PORTIONS OF THE BIG HORN RANGE
THE SNOW HAS BEEN FAIRLY SPARSE. SOME PERIODS OF SNOW SHOULD
CONTINUE INTO THE EVENING WITH SOME UPPER LEVEL SUPPORT FROM THE
LEFT FRONT QUADRANT OF A JET STREAK MOVING ACROSS THE AREA. WE
THROUGH ABOUT AN ADVISORY FOR THE LANDER FOOTHILLS BUT THE RADAR
TRENDS HAVE BEEN DECREASING OVER THE PAST 30 MINUTES SO WE WILL
STICK TO AN SPS AT THIS TIME. WITH UNSTABLE NORTHWEST FLOW SOME SNOW
SHOWERS WILL CONTINUE THROUGH THE NIGHT ALTHOUGH THE COVERAGE
SHOULD DECREASE AS WE HEAD INTO THE EVENING. AS FOR THE
ADVISORIES...THERE WAS ACTUALLY A BREAK BUT ANOTHER BATCH IS ON
THE WAY. FOR NOW...WE WILL PROBABLY LET THEM RIDE INTO THE EVENING
UNLESS OUR NEIGHBORS HAVE ANY DISAGREEMENTS. WE STILL FEEL THERE
COULD BE A PROBLEM WITH INTERSTATE 80 AS THE BAND MOVES SOUTHWARD
ACROSS SWEETWATER COUNTY AS WELL.

AS FOR TOMORROW...IT LOOKS TO BE SOMEWHAT LESS ACTIVE ALTHOUGH STILL
COLD AND UNSETTLED. WITH UNSTABLE NORTHWEST FLOW CONTINUING OVER THE
AREA AS WELL AS CYCLONIC CURVATURE REMAINING...WE HAVE CONTINUED THE
CHANCE OF SNOW SHOWERS ACROSS PORTIONS OF THE AREA. ONCE
AGAIN...PINPOINTING THEM AT THIS POINT IS NEARLY IMPOSSIBLE...BUT
MANY AREAS WILL HAVE A CHANCE. WITH FRESH SNOW COVER MANY AREAS WILL
STRUGGLE TO GET ABOVE FREEZING.

.LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY

SOME SNOW WILL LINGER OVER THE MOUNTAINS AND SOUTH WITH
CLEARING IN THE NORTH SPREADING SOUTH THROUGH THE NIGHT.
TEMPERATURES WILL BECOME QUITE COLD AGAIN AS VERY COLD CANADIAN
AIR MOVES IN AND COMBINES WITH STRONG RADIATIONAL COOLING.
FRIDAY A PACIFIC TROUGH MOVING RAPIDLY INLAND WILL START BRINGING
AREAS OF SNOW TO THE WEST WITH BREEZY TO WINDY AREAS EAST OF THE
CONTINENTAL DIVIDE.  TEMPERATURES WILL BEGIN TO WARM WITH DOWNSLOPE
WINDS OVER AND NEAR THE EAST SLOPES OF THE MOUNTAINS.  A CANADIAN
COLD FRONT WILL MOVE SOUTH BEHIND THE PACIFIC TROUGH FRIDAY NIGHT
AND SATURDAY WITH MORE AREAS OF SNOW DEVELOPING EAST OF THE
CONTINENTAL DIVIDE WHILE REMAINING OVER THE WESTERN MOUNTAINS.
THIS COLD FRONT WILL SWEEP SOUTH SATURDAY NIGHT WITH DRYING MOVING
INTO THE NORTH ON SUNDAY.  AGAIN VERY COLD AIR WILL INTRUDE FROM THE
NORTH.  SUNDAY NIGHT WILL BE COLD WITH CLEARING. THEN YET ANOTHER
PACIFIC TROUGH WILL RACE EAST MONDAY WITH SNOW MOVING BACK INTO THE
WEST AND WINDS INCREASING EAST OF THE CONTINENTAL DIVIDE WITH
DOWNSLOPE WARMING RETURNING...ONLY TO BE FOLLOWED BY ANOTHER CANADIAN
COLD FRONT MONDAY NIGHT AND TUESDAY SPREADING AREAS OF SNOW ACROSS
THE AREA EAST OF THE CONTINENTAL DIVIDE.  SNOW WILL BE RATHER
WIDESPREAD TUESDAY NIGHT WITH CLEARING ON WEDNESDAY WITH MORE COLD
CANADIAN AIR MOVING IN.  A VERY PROGRESSIVE PATTERN IS IN STORE WITH
TIMING ISSUES LIKELY THROUGH THE PERIOD...INCREASING SIGNIFICANTLY
WITH TIME.

&&

.AVIATION.../06Z ISSUANCE/

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

MVFR TO IFR CONDITIONS WILL OCCUR AT SOME TERMINAL SITES OVERNIGHT
THROUGH THURSDAY AFTERNOON. AREAS OF LIGHT SNOW WILL OCCUR AS WELL
THROUGH 00Z FRIDAY. EXPECT MOUNTAIN OBSCURATION AT TIMES THROUGH 00Z
FRIDAY. AFTER 00Z FRIDAY VFR CONDITIONS WILL PREVAIL OVER THE AREA.
HOWEVER LOCAL MVFR CONDITIONS WILL BE POSSIBLE DUE TO LOW CLOUDS
THROUGH 06Z FRI.

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

VFR TO MVFR CONDITIONS WILL OCCUR OVER SOUTHWEST WY OVERNIGHT
THROUGH THURSDAY AFTERNOON. AREAS OF LIGHT SNOW WILL ALSO OCCUR
THROUGH 00Z FRIDAY. EXPECT MOUNTAIN OBSCURATION AT TIMES THROUGH 00Z
FRIDAY. AFTER 00Z FRIDAY VFR CONDITIONS WILL PREVAIL OVER THE REGION.

&&

.FIRE WEATHER...

OCCASIONAL SNOW WILL CONTINUE INTO TONIGHT ALTHOUGH COVERAGE WILL
SHRINK INTO THE NIGHT GUSTY NORTH TO NORTHEASTERLY WINDS WILL ALSO
GRADUALLY DECREASE INTO THE NIGHT. A CHANCE OF SNOW SHOWERS WILL
LINGER INTO TOMORROW AS WELL WITH UNSTABLE NORTHWESTERLY FLOW
CONTINUING. HOWEVER...PINPOINTING THEM IS VERY DIFFICULT. WITH FRESH
SNOW COVER IN SOME OF THE BASINS INVERSIONS MAY FORM TONIGHT AND
INTO TOMORROW RESULTING IN LOW MIXING HEIGHTS AND POOR SMOKE
DISPERSAL.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

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









000
FXUS65 KCYS 260420
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
920 PM MST WED FEB 25 2015

.UPDATE...
ISSUED AT 916 PM MST WED FEB 25 2015

LATEST RADAR IMAGERY...INFRARED SATELLITE IMAGERY AND AREA
OBSERVATIONS ARE ALL SHOWING SNOW EASING OVER THE AREA. WENT AHEAD
AND CANCELLED SNOW ADVISORY EARLY AS FURTHER ACCUMULATING SNOW NO
LONGER EXPECTED. UPDATES HAVE BEEN SENT.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 309 PM MST WED FEB 25 2015

SFC COLD FRONT HAS SLID SOUTH OF THE CWFA TODAY LEAVING NORTHERLY
LLVL WINDS IN ITS WAKE. MODERATE TO AT TIMES HEAVY BANDS OF SNOW
DEVELOPED INITIALLY OVR THE HIER TERRAIN AS WELL AS ACROSS
NORTHEASTERN LARAMIE COUNTY. THIS POCKET OF MODERATE SNOW EXPANDED
AS IT SHIFTED WEST THRU MUCH OF THE DAY WITH THE MOST INTENSE AXIS
AT 21Z SETTLING ON THE SRN LARAMIE RANGE. LATEST SATELLITE PIX
SHOW CONVECTIVE ELEMENTS ESPECIALLY OVR THE HIER TERRAIN OF SRN
CARBON COUNTY WHERE INSTABILITY WAS PROGD TO BE THE GREATEST.
AREAS OF BLOWING SNOW IS ALSO A CONCERN WITH RECENT WIND GUSTS
OBSERVED AT 25- 35 MPH ACROSS SE WYOMING. IN AN EARLIER UPDATE
EXPANDED THE WINTER WEATHER ADVISORY INTO ARLINGTON AS WELL AS OVR
THE SRN LARAMIE RANGE FOOTHILLS LARAMIE COUNTY...WHERE SNOWFALL
RATES FROM BOTH WEBCAMS AND KCYS RADAR RETURNS WERE THE GREATEST.
THESE SNOWFALL RATES WILL WANE SOMEWHAT WITH INSTABILITY LOSS THIS
EVENING...THOUGH LINGERING LIGHT SNOW WILL STILL BE A GOOD
POSSIBILITY. IF SNOWFALL RATES ALLOW...EVENING SHIFT MAY BE ABLE
TO CANX THE ADVISORY EARLY. A COLD NIGHT AHEAD...ESPECIALLY ACROSS
SOUTHEAST WYOMING WHERE THE COMBINATION OF FRESH SNOWPACK AND SOME
LLVL CAA PLUMMET LOW TEMPERATURES TO AROUND 0F IN THE LARAMIE
VALLEY AND SINGLE DIGITS ELSEWHERE.

ALTHOUGH BEST SHORTWAVE ENERGY SHIFTS SOUTH OVERNIGHT...LLVL
FRONT WILL BECOME STATIONARY ACROSS CARBON COUNTY AT LEAST THRU
THE DAY ON THURSDAY. MODELS SUGGEST A SECONDARY SHORTWAVE WILL
PUSH ATOP THE FRONT PRODUCING SOME PERIODS OF LIGHT SNOW OR
FLURRIES. HIER ELEVATIONS AND AREAS NR THE CO/WY STATELINE WILL
HAVE THE BEST OPPORTUNITY TO SEE LT SNOW ON THURSDAY. ANY
ACCUMULATIONS WILL BE VERY LIGHT WITH PERHAPS UP TO AN INCH
POSSIBLE. THURSDAY WILL BE COLDER HOWEVER WITH HIGHS THAT WILL
RISE GENERALLY JUST INTO THE TEENS.

THE PATTERN BEGINS TO FLATTEN ON FRIDAY AS THE NEXT UPSTREAM
TROUGH CARVES TOWARDS THE GREAT BASIN. LLVL FLOW TURNS SOUTHEAST
AHEAD OF IT WHICH IS TYPICALLY A FAVORABLE FOG PATTERN FOR THE
CHEYENNE RIDGE AND LARAMIE COUNTY. SO IT WILL LIKELY BE A
CLOUDY/FOGGY START TO THE DAY FOR FRIDAY. FLATTENING FLOW WILL
PUSH THE FRONT EAST TO AROUND THE LARAMIE RANGE BY LATE FRIDAY.
THIS WILL HELP TEMPERATURES UP A FEW DEGREES WITH TEENS AND 20S
EXPECTED MOST AREAS. OUTSIDE OF MOUNTAIN LOCATIONS...SNOW CHANCES
WILL BE MINIMAL ON FRIDAY.

.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 309 PM MST WED FEB 25 2015

SATURDAY...ARCTIC AIR REMAINS ENTRENCHED THUS STILL WELL BELOW
NORMAL TEMPERATURES. SUFFICIENTLY MOIST AIRMASS PROGGED AND WITH
SOUTHWEST FLOW ALOFT AND AN APPROACHING SHORTWAVE TROUGH ALOFT AND
OROGRAPHICS...WILL SEE WIDESPREAD SNOWS OVER THE SNOWY AND SIERRA
MADRE RANGES WITH SCATTERED SNOW SHOWERS NEARBY.

SUNDAY...MOIST SOUTHWEST FLOW ALOFT CONTINUES PRODUCING WIDESPREAD
OROGRAPHIC SNOWS OVER OUR NORTHERN LARAMIE...SNOWY AND SIERRA MADRE
RANGES WITH MOSTLY DRY CONDITIONS ELSEWHERE. CONTINUED COLD WITH
ARCTIC AIR ENTRENCHED.

MONDAY...ARCTIC AIR WILL RETREAT EASTWARD WITH TEMPERATURES WARMING.
GFS LOOKS OVERDONE WITH QPF WITH THE SHORTWAVE TROUGH ALOFT MOVING
ACROSS AND PREFER THE LESS AMPLIFIED AND DRIER ECMWF VERSION WHICH
MESHES WELL WITH OUR SURROUNDING NEIGHBORING OFFICES...THUS EXPECT
SCATTERED OROGRAPHIC SNOWS OVER THE SNOWY AND SIERRA MADRE RANGES
AND DRY ELSEWHERE.

TUESDAY...COLD TEMPERATURES CONTINUE IN THE WAKE OF ANOTHER PASSING
ARCTIC COLD FRONT. MOIST WEST FLOW ALOFT AND ADEQUATE LOW AND MID
LEVEL MOISTURE WILL KEEP SCATTERED SNOWS WEST OF INTERSTATE 25 AND
MOSTLY DRY ELSEWHERE DUE TO DOWNSLOPING MID LEVEL WINDS.

WEDNESDAY...FLOW ALOFT TURNS NORTHWEST. NOW THE ECMWF LOOKS OVERDONE
WITH RESPECT TO QPF AND PREFER THE DRIER GFS VERSION SHOWING DRY AND
COLD NORTHWEST FLOW ALOFT...THUS EXPECT A WINDY DAY WITH PERHAPS A
FEW MOUNTAIN SNOW SHOWERS...AND DRY ELSEWHERE...WHICH MESHES WELL
WITH OUR SURROUNDING NEIGHBORING OFFICES.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 916 PM MST WED FEB 25 2015

LATEST HRRR GUIDANCE USED FOR THE 06Z TAFS ACROSS SOUTHEAST
WYOMING AND NEBRASKA PANHANDLE. CEILINGS ARE COMING DOWN HERE AT
KCYS AND HRRR SHOWING A SMALL PERSISTENT IFR AREA OVER KCYS. LOOKS
LIKE WE COULD GET ANOTHER SHOT AT IFR CONDITIONS THURSDAY
AFTERNOON AS THE AREA SEES A WIDESPREAD LIGHT SNOW EVENT.

&&

.FIRE WEATHER...
ISSUED AT 309 PM MST WED FEB 25 2015

COLD TEMPERATURES AND UNSETTLED CONDITIONS WILL HOLD ANY FIRE
WEATHER CONCERNS AT BAY FOR THE FORESEEABLE FUTURE.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

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




000
FXUS65 KCYS 260420
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
920 PM MST WED FEB 25 2015

.UPDATE...
ISSUED AT 916 PM MST WED FEB 25 2015

LATEST RADAR IMAGERY...INFRARED SATELLITE IMAGERY AND AREA
OBSERVATIONS ARE ALL SHOWING SNOW EASING OVER THE AREA. WENT AHEAD
AND CANCELLED SNOW ADVISORY EARLY AS FURTHER ACCUMULATING SNOW NO
LONGER EXPECTED. UPDATES HAVE BEEN SENT.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 309 PM MST WED FEB 25 2015

SFC COLD FRONT HAS SLID SOUTH OF THE CWFA TODAY LEAVING NORTHERLY
LLVL WINDS IN ITS WAKE. MODERATE TO AT TIMES HEAVY BANDS OF SNOW
DEVELOPED INITIALLY OVR THE HIER TERRAIN AS WELL AS ACROSS
NORTHEASTERN LARAMIE COUNTY. THIS POCKET OF MODERATE SNOW EXPANDED
AS IT SHIFTED WEST THRU MUCH OF THE DAY WITH THE MOST INTENSE AXIS
AT 21Z SETTLING ON THE SRN LARAMIE RANGE. LATEST SATELLITE PIX
SHOW CONVECTIVE ELEMENTS ESPECIALLY OVR THE HIER TERRAIN OF SRN
CARBON COUNTY WHERE INSTABILITY WAS PROGD TO BE THE GREATEST.
AREAS OF BLOWING SNOW IS ALSO A CONCERN WITH RECENT WIND GUSTS
OBSERVED AT 25- 35 MPH ACROSS SE WYOMING. IN AN EARLIER UPDATE
EXPANDED THE WINTER WEATHER ADVISORY INTO ARLINGTON AS WELL AS OVR
THE SRN LARAMIE RANGE FOOTHILLS LARAMIE COUNTY...WHERE SNOWFALL
RATES FROM BOTH WEBCAMS AND KCYS RADAR RETURNS WERE THE GREATEST.
THESE SNOWFALL RATES WILL WANE SOMEWHAT WITH INSTABILITY LOSS THIS
EVENING...THOUGH LINGERING LIGHT SNOW WILL STILL BE A GOOD
POSSIBILITY. IF SNOWFALL RATES ALLOW...EVENING SHIFT MAY BE ABLE
TO CANX THE ADVISORY EARLY. A COLD NIGHT AHEAD...ESPECIALLY ACROSS
SOUTHEAST WYOMING WHERE THE COMBINATION OF FRESH SNOWPACK AND SOME
LLVL CAA PLUMMET LOW TEMPERATURES TO AROUND 0F IN THE LARAMIE
VALLEY AND SINGLE DIGITS ELSEWHERE.

ALTHOUGH BEST SHORTWAVE ENERGY SHIFTS SOUTH OVERNIGHT...LLVL
FRONT WILL BECOME STATIONARY ACROSS CARBON COUNTY AT LEAST THRU
THE DAY ON THURSDAY. MODELS SUGGEST A SECONDARY SHORTWAVE WILL
PUSH ATOP THE FRONT PRODUCING SOME PERIODS OF LIGHT SNOW OR
FLURRIES. HIER ELEVATIONS AND AREAS NR THE CO/WY STATELINE WILL
HAVE THE BEST OPPORTUNITY TO SEE LT SNOW ON THURSDAY. ANY
ACCUMULATIONS WILL BE VERY LIGHT WITH PERHAPS UP TO AN INCH
POSSIBLE. THURSDAY WILL BE COLDER HOWEVER WITH HIGHS THAT WILL
RISE GENERALLY JUST INTO THE TEENS.

THE PATTERN BEGINS TO FLATTEN ON FRIDAY AS THE NEXT UPSTREAM
TROUGH CARVES TOWARDS THE GREAT BASIN. LLVL FLOW TURNS SOUTHEAST
AHEAD OF IT WHICH IS TYPICALLY A FAVORABLE FOG PATTERN FOR THE
CHEYENNE RIDGE AND LARAMIE COUNTY. SO IT WILL LIKELY BE A
CLOUDY/FOGGY START TO THE DAY FOR FRIDAY. FLATTENING FLOW WILL
PUSH THE FRONT EAST TO AROUND THE LARAMIE RANGE BY LATE FRIDAY.
THIS WILL HELP TEMPERATURES UP A FEW DEGREES WITH TEENS AND 20S
EXPECTED MOST AREAS. OUTSIDE OF MOUNTAIN LOCATIONS...SNOW CHANCES
WILL BE MINIMAL ON FRIDAY.

.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 309 PM MST WED FEB 25 2015

SATURDAY...ARCTIC AIR REMAINS ENTRENCHED THUS STILL WELL BELOW
NORMAL TEMPERATURES. SUFFICIENTLY MOIST AIRMASS PROGGED AND WITH
SOUTHWEST FLOW ALOFT AND AN APPROACHING SHORTWAVE TROUGH ALOFT AND
OROGRAPHICS...WILL SEE WIDESPREAD SNOWS OVER THE SNOWY AND SIERRA
MADRE RANGES WITH SCATTERED SNOW SHOWERS NEARBY.

SUNDAY...MOIST SOUTHWEST FLOW ALOFT CONTINUES PRODUCING WIDESPREAD
OROGRAPHIC SNOWS OVER OUR NORTHERN LARAMIE...SNOWY AND SIERRA MADRE
RANGES WITH MOSTLY DRY CONDITIONS ELSEWHERE. CONTINUED COLD WITH
ARCTIC AIR ENTRENCHED.

MONDAY...ARCTIC AIR WILL RETREAT EASTWARD WITH TEMPERATURES WARMING.
GFS LOOKS OVERDONE WITH QPF WITH THE SHORTWAVE TROUGH ALOFT MOVING
ACROSS AND PREFER THE LESS AMPLIFIED AND DRIER ECMWF VERSION WHICH
MESHES WELL WITH OUR SURROUNDING NEIGHBORING OFFICES...THUS EXPECT
SCATTERED OROGRAPHIC SNOWS OVER THE SNOWY AND SIERRA MADRE RANGES
AND DRY ELSEWHERE.

TUESDAY...COLD TEMPERATURES CONTINUE IN THE WAKE OF ANOTHER PASSING
ARCTIC COLD FRONT. MOIST WEST FLOW ALOFT AND ADEQUATE LOW AND MID
LEVEL MOISTURE WILL KEEP SCATTERED SNOWS WEST OF INTERSTATE 25 AND
MOSTLY DRY ELSEWHERE DUE TO DOWNSLOPING MID LEVEL WINDS.

WEDNESDAY...FLOW ALOFT TURNS NORTHWEST. NOW THE ECMWF LOOKS OVERDONE
WITH RESPECT TO QPF AND PREFER THE DRIER GFS VERSION SHOWING DRY AND
COLD NORTHWEST FLOW ALOFT...THUS EXPECT A WINDY DAY WITH PERHAPS A
FEW MOUNTAIN SNOW SHOWERS...AND DRY ELSEWHERE...WHICH MESHES WELL
WITH OUR SURROUNDING NEIGHBORING OFFICES.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 916 PM MST WED FEB 25 2015

LATEST HRRR GUIDANCE USED FOR THE 06Z TAFS ACROSS SOUTHEAST
WYOMING AND NEBRASKA PANHANDLE. CEILINGS ARE COMING DOWN HERE AT
KCYS AND HRRR SHOWING A SMALL PERSISTENT IFR AREA OVER KCYS. LOOKS
LIKE WE COULD GET ANOTHER SHOT AT IFR CONDITIONS THURSDAY
AFTERNOON AS THE AREA SEES A WIDESPREAD LIGHT SNOW EVENT.

&&

.FIRE WEATHER...
ISSUED AT 309 PM MST WED FEB 25 2015

COLD TEMPERATURES AND UNSETTLED CONDITIONS WILL HOLD ANY FIRE
WEATHER CONCERNS AT BAY FOR THE FORESEEABLE FUTURE.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

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




000
FXUS65 KCYS 260420
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
920 PM MST WED FEB 25 2015

.UPDATE...
ISSUED AT 916 PM MST WED FEB 25 2015

LATEST RADAR IMAGERY...INFRARED SATELLITE IMAGERY AND AREA
OBSERVATIONS ARE ALL SHOWING SNOW EASING OVER THE AREA. WENT AHEAD
AND CANCELLED SNOW ADVISORY EARLY AS FURTHER ACCUMULATING SNOW NO
LONGER EXPECTED. UPDATES HAVE BEEN SENT.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 309 PM MST WED FEB 25 2015

SFC COLD FRONT HAS SLID SOUTH OF THE CWFA TODAY LEAVING NORTHERLY
LLVL WINDS IN ITS WAKE. MODERATE TO AT TIMES HEAVY BANDS OF SNOW
DEVELOPED INITIALLY OVR THE HIER TERRAIN AS WELL AS ACROSS
NORTHEASTERN LARAMIE COUNTY. THIS POCKET OF MODERATE SNOW EXPANDED
AS IT SHIFTED WEST THRU MUCH OF THE DAY WITH THE MOST INTENSE AXIS
AT 21Z SETTLING ON THE SRN LARAMIE RANGE. LATEST SATELLITE PIX
SHOW CONVECTIVE ELEMENTS ESPECIALLY OVR THE HIER TERRAIN OF SRN
CARBON COUNTY WHERE INSTABILITY WAS PROGD TO BE THE GREATEST.
AREAS OF BLOWING SNOW IS ALSO A CONCERN WITH RECENT WIND GUSTS
OBSERVED AT 25- 35 MPH ACROSS SE WYOMING. IN AN EARLIER UPDATE
EXPANDED THE WINTER WEATHER ADVISORY INTO ARLINGTON AS WELL AS OVR
THE SRN LARAMIE RANGE FOOTHILLS LARAMIE COUNTY...WHERE SNOWFALL
RATES FROM BOTH WEBCAMS AND KCYS RADAR RETURNS WERE THE GREATEST.
THESE SNOWFALL RATES WILL WANE SOMEWHAT WITH INSTABILITY LOSS THIS
EVENING...THOUGH LINGERING LIGHT SNOW WILL STILL BE A GOOD
POSSIBILITY. IF SNOWFALL RATES ALLOW...EVENING SHIFT MAY BE ABLE
TO CANX THE ADVISORY EARLY. A COLD NIGHT AHEAD...ESPECIALLY ACROSS
SOUTHEAST WYOMING WHERE THE COMBINATION OF FRESH SNOWPACK AND SOME
LLVL CAA PLUMMET LOW TEMPERATURES TO AROUND 0F IN THE LARAMIE
VALLEY AND SINGLE DIGITS ELSEWHERE.

ALTHOUGH BEST SHORTWAVE ENERGY SHIFTS SOUTH OVERNIGHT...LLVL
FRONT WILL BECOME STATIONARY ACROSS CARBON COUNTY AT LEAST THRU
THE DAY ON THURSDAY. MODELS SUGGEST A SECONDARY SHORTWAVE WILL
PUSH ATOP THE FRONT PRODUCING SOME PERIODS OF LIGHT SNOW OR
FLURRIES. HIER ELEVATIONS AND AREAS NR THE CO/WY STATELINE WILL
HAVE THE BEST OPPORTUNITY TO SEE LT SNOW ON THURSDAY. ANY
ACCUMULATIONS WILL BE VERY LIGHT WITH PERHAPS UP TO AN INCH
POSSIBLE. THURSDAY WILL BE COLDER HOWEVER WITH HIGHS THAT WILL
RISE GENERALLY JUST INTO THE TEENS.

THE PATTERN BEGINS TO FLATTEN ON FRIDAY AS THE NEXT UPSTREAM
TROUGH CARVES TOWARDS THE GREAT BASIN. LLVL FLOW TURNS SOUTHEAST
AHEAD OF IT WHICH IS TYPICALLY A FAVORABLE FOG PATTERN FOR THE
CHEYENNE RIDGE AND LARAMIE COUNTY. SO IT WILL LIKELY BE A
CLOUDY/FOGGY START TO THE DAY FOR FRIDAY. FLATTENING FLOW WILL
PUSH THE FRONT EAST TO AROUND THE LARAMIE RANGE BY LATE FRIDAY.
THIS WILL HELP TEMPERATURES UP A FEW DEGREES WITH TEENS AND 20S
EXPECTED MOST AREAS. OUTSIDE OF MOUNTAIN LOCATIONS...SNOW CHANCES
WILL BE MINIMAL ON FRIDAY.

.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 309 PM MST WED FEB 25 2015

SATURDAY...ARCTIC AIR REMAINS ENTRENCHED THUS STILL WELL BELOW
NORMAL TEMPERATURES. SUFFICIENTLY MOIST AIRMASS PROGGED AND WITH
SOUTHWEST FLOW ALOFT AND AN APPROACHING SHORTWAVE TROUGH ALOFT AND
OROGRAPHICS...WILL SEE WIDESPREAD SNOWS OVER THE SNOWY AND SIERRA
MADRE RANGES WITH SCATTERED SNOW SHOWERS NEARBY.

SUNDAY...MOIST SOUTHWEST FLOW ALOFT CONTINUES PRODUCING WIDESPREAD
OROGRAPHIC SNOWS OVER OUR NORTHERN LARAMIE...SNOWY AND SIERRA MADRE
RANGES WITH MOSTLY DRY CONDITIONS ELSEWHERE. CONTINUED COLD WITH
ARCTIC AIR ENTRENCHED.

MONDAY...ARCTIC AIR WILL RETREAT EASTWARD WITH TEMPERATURES WARMING.
GFS LOOKS OVERDONE WITH QPF WITH THE SHORTWAVE TROUGH ALOFT MOVING
ACROSS AND PREFER THE LESS AMPLIFIED AND DRIER ECMWF VERSION WHICH
MESHES WELL WITH OUR SURROUNDING NEIGHBORING OFFICES...THUS EXPECT
SCATTERED OROGRAPHIC SNOWS OVER THE SNOWY AND SIERRA MADRE RANGES
AND DRY ELSEWHERE.

TUESDAY...COLD TEMPERATURES CONTINUE IN THE WAKE OF ANOTHER PASSING
ARCTIC COLD FRONT. MOIST WEST FLOW ALOFT AND ADEQUATE LOW AND MID
LEVEL MOISTURE WILL KEEP SCATTERED SNOWS WEST OF INTERSTATE 25 AND
MOSTLY DRY ELSEWHERE DUE TO DOWNSLOPING MID LEVEL WINDS.

WEDNESDAY...FLOW ALOFT TURNS NORTHWEST. NOW THE ECMWF LOOKS OVERDONE
WITH RESPECT TO QPF AND PREFER THE DRIER GFS VERSION SHOWING DRY AND
COLD NORTHWEST FLOW ALOFT...THUS EXPECT A WINDY DAY WITH PERHAPS A
FEW MOUNTAIN SNOW SHOWERS...AND DRY ELSEWHERE...WHICH MESHES WELL
WITH OUR SURROUNDING NEIGHBORING OFFICES.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 916 PM MST WED FEB 25 2015

LATEST HRRR GUIDANCE USED FOR THE 06Z TAFS ACROSS SOUTHEAST
WYOMING AND NEBRASKA PANHANDLE. CEILINGS ARE COMING DOWN HERE AT
KCYS AND HRRR SHOWING A SMALL PERSISTENT IFR AREA OVER KCYS. LOOKS
LIKE WE COULD GET ANOTHER SHOT AT IFR CONDITIONS THURSDAY
AFTERNOON AS THE AREA SEES A WIDESPREAD LIGHT SNOW EVENT.

&&

.FIRE WEATHER...
ISSUED AT 309 PM MST WED FEB 25 2015

COLD TEMPERATURES AND UNSETTLED CONDITIONS WILL HOLD ANY FIRE
WEATHER CONCERNS AT BAY FOR THE FORESEEABLE FUTURE.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

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




000
FXUS65 KCYS 260420
AFDCYS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
920 PM MST WED FEB 25 2015

.UPDATE...
ISSUED AT 916 PM MST WED FEB 25 2015

LATEST RADAR IMAGERY...INFRARED SATELLITE IMAGERY AND AREA
OBSERVATIONS ARE ALL SHOWING SNOW EASING OVER THE AREA. WENT AHEAD
AND CANCELLED SNOW ADVISORY EARLY AS FURTHER ACCUMULATING SNOW NO
LONGER EXPECTED. UPDATES HAVE BEEN SENT.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 309 PM MST WED FEB 25 2015

SFC COLD FRONT HAS SLID SOUTH OF THE CWFA TODAY LEAVING NORTHERLY
LLVL WINDS IN ITS WAKE. MODERATE TO AT TIMES HEAVY BANDS OF SNOW
DEVELOPED INITIALLY OVR THE HIER TERRAIN AS WELL AS ACROSS
NORTHEASTERN LARAMIE COUNTY. THIS POCKET OF MODERATE SNOW EXPANDED
AS IT SHIFTED WEST THRU MUCH OF THE DAY WITH THE MOST INTENSE AXIS
AT 21Z SETTLING ON THE SRN LARAMIE RANGE. LATEST SATELLITE PIX
SHOW CONVECTIVE ELEMENTS ESPECIALLY OVR THE HIER TERRAIN OF SRN
CARBON COUNTY WHERE INSTABILITY WAS PROGD TO BE THE GREATEST.
AREAS OF BLOWING SNOW IS ALSO A CONCERN WITH RECENT WIND GUSTS
OBSERVED AT 25- 35 MPH ACROSS SE WYOMING. IN AN EARLIER UPDATE
EXPANDED THE WINTER WEATHER ADVISORY INTO ARLINGTON AS WELL AS OVR
THE SRN LARAMIE RANGE FOOTHILLS LARAMIE COUNTY...WHERE SNOWFALL
RATES FROM BOTH WEBCAMS AND KCYS RADAR RETURNS WERE THE GREATEST.
THESE SNOWFALL RATES WILL WANE SOMEWHAT WITH INSTABILITY LOSS THIS
EVENING...THOUGH LINGERING LIGHT SNOW WILL STILL BE A GOOD
POSSIBILITY. IF SNOWFALL RATES ALLOW...EVENING SHIFT MAY BE ABLE
TO CANX THE ADVISORY EARLY. A COLD NIGHT AHEAD...ESPECIALLY ACROSS
SOUTHEAST WYOMING WHERE THE COMBINATION OF FRESH SNOWPACK AND SOME
LLVL CAA PLUMMET LOW TEMPERATURES TO AROUND 0F IN THE LARAMIE
VALLEY AND SINGLE DIGITS ELSEWHERE.

ALTHOUGH BEST SHORTWAVE ENERGY SHIFTS SOUTH OVERNIGHT...LLVL
FRONT WILL BECOME STATIONARY ACROSS CARBON COUNTY AT LEAST THRU
THE DAY ON THURSDAY. MODELS SUGGEST A SECONDARY SHORTWAVE WILL
PUSH ATOP THE FRONT PRODUCING SOME PERIODS OF LIGHT SNOW OR
FLURRIES. HIER ELEVATIONS AND AREAS NR THE CO/WY STATELINE WILL
HAVE THE BEST OPPORTUNITY TO SEE LT SNOW ON THURSDAY. ANY
ACCUMULATIONS WILL BE VERY LIGHT WITH PERHAPS UP TO AN INCH
POSSIBLE. THURSDAY WILL BE COLDER HOWEVER WITH HIGHS THAT WILL
RISE GENERALLY JUST INTO THE TEENS.

THE PATTERN BEGINS TO FLATTEN ON FRIDAY AS THE NEXT UPSTREAM
TROUGH CARVES TOWARDS THE GREAT BASIN. LLVL FLOW TURNS SOUTHEAST
AHEAD OF IT WHICH IS TYPICALLY A FAVORABLE FOG PATTERN FOR THE
CHEYENNE RIDGE AND LARAMIE COUNTY. SO IT WILL LIKELY BE A
CLOUDY/FOGGY START TO THE DAY FOR FRIDAY. FLATTENING FLOW WILL
PUSH THE FRONT EAST TO AROUND THE LARAMIE RANGE BY LATE FRIDAY.
THIS WILL HELP TEMPERATURES UP A FEW DEGREES WITH TEENS AND 20S
EXPECTED MOST AREAS. OUTSIDE OF MOUNTAIN LOCATIONS...SNOW CHANCES
WILL BE MINIMAL ON FRIDAY.

.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 309 PM MST WED FEB 25 2015

SATURDAY...ARCTIC AIR REMAINS ENTRENCHED THUS STILL WELL BELOW
NORMAL TEMPERATURES. SUFFICIENTLY MOIST AIRMASS PROGGED AND WITH
SOUTHWEST FLOW ALOFT AND AN APPROACHING SHORTWAVE TROUGH ALOFT AND
OROGRAPHICS...WILL SEE WIDESPREAD SNOWS OVER THE SNOWY AND SIERRA
MADRE RANGES WITH SCATTERED SNOW SHOWERS NEARBY.

SUNDAY...MOIST SOUTHWEST FLOW ALOFT CONTINUES PRODUCING WIDESPREAD
OROGRAPHIC SNOWS OVER OUR NORTHERN LARAMIE...SNOWY AND SIERRA MADRE
RANGES WITH MOSTLY DRY CONDITIONS ELSEWHERE. CONTINUED COLD WITH
ARCTIC AIR ENTRENCHED.

MONDAY...ARCTIC AIR WILL RETREAT EASTWARD WITH TEMPERATURES WARMING.
GFS LOOKS OVERDONE WITH QPF WITH THE SHORTWAVE TROUGH ALOFT MOVING
ACROSS AND PREFER THE LESS AMPLIFIED AND DRIER ECMWF VERSION WHICH
MESHES WELL WITH OUR SURROUNDING NEIGHBORING OFFICES...THUS EXPECT
SCATTERED OROGRAPHIC SNOWS OVER THE SNOWY AND SIERRA MADRE RANGES
AND DRY ELSEWHERE.

TUESDAY...COLD TEMPERATURES CONTINUE IN THE WAKE OF ANOTHER PASSING
ARCTIC COLD FRONT. MOIST WEST FLOW ALOFT AND ADEQUATE LOW AND MID
LEVEL MOISTURE WILL KEEP SCATTERED SNOWS WEST OF INTERSTATE 25 AND
MOSTLY DRY ELSEWHERE DUE TO DOWNSLOPING MID LEVEL WINDS.

WEDNESDAY...FLOW ALOFT TURNS NORTHWEST. NOW THE ECMWF LOOKS OVERDONE
WITH RESPECT TO QPF AND PREFER THE DRIER GFS VERSION SHOWING DRY AND
COLD NORTHWEST FLOW ALOFT...THUS EXPECT A WINDY DAY WITH PERHAPS A
FEW MOUNTAIN SNOW SHOWERS...AND DRY ELSEWHERE...WHICH MESHES WELL
WITH OUR SURROUNDING NEIGHBORING OFFICES.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 916 PM MST WED FEB 25 2015

LATEST HRRR GUIDANCE USED FOR THE 06Z TAFS ACROSS SOUTHEAST
WYOMING AND NEBRASKA PANHANDLE. CEILINGS ARE COMING DOWN HERE AT
KCYS AND HRRR SHOWING A SMALL PERSISTENT IFR AREA OVER KCYS. LOOKS
LIKE WE COULD GET ANOTHER SHOT AT IFR CONDITIONS THURSDAY
AFTERNOON AS THE AREA SEES A WIDESPREAD LIGHT SNOW EVENT.

&&

.FIRE WEATHER...
ISSUED AT 309 PM MST WED FEB 25 2015

COLD TEMPERATURES AND UNSETTLED CONDITIONS WILL HOLD ANY FIRE
WEATHER CONCERNS AT BAY FOR THE FORESEEABLE FUTURE.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&

$$

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




000
FXUS63 KUNR 260411
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
911 PM MST WED FEB 25 2015

.UPDATE...
ISSUED AT 907 PM MST WED FEB 25 2015

LATEST RADAR TRENDS AND 00Z GUIDANCE SHOW -SN WINDING DOWN AS
FORCING SHIFTS SOUTH...BOUNDARY LAYER STARTS TO DRY OUT...AND
SUBSIDENCE STARTS TO KICK IN COURTESY OF 1042MB ARCTIC HIGH NOSING
INTO THE DAKOTAS.

WILL ALLOW HEADLINES TO EXPIRE ON SCHEDULE AT MIDNIGHT GIVEN -SN
STILL OCCURRING AND ROADS MESSY IN PLACES.

UPDATE ISSUED AT 405 PM MST WED FEB 25 2015

RECENT STORM REPORTS SHOWED AROUND AN INCH OF SNOW OVER PORTIONS
OF NORTHWEST SD. LATEST RADAR LOOP SHOWED -SN CONTINUING OVER
THESE AREAS AT LEAST INTO THE EARLY EVENING HOURS...SO HAVE
UPDATED TO RAISE POPS CONSIDERABLY...BUT THINGS STILL LOOK LIKE
THEY WILL TAPER OFF LATER THIS EVENING.

&&

.SHORT TERM...THIS EVENING THROUGH THURSDAY NIGHT
ISSUED AT 246 PM MST WED FEB 25 2015

UPPER AIR ANALYSIS SHOWS A BROAD UPPER TROUGH ACROSS THE ERN TWO
THIRDS OF THE CWA WITH NW FLOW CONTINUING ACROSS THE NRN PLAINS.
SEVERAL EMBEDDED SHORTWAVES ARE PUSHING THROUGH THE CANADIAN HIGH
PLAINS INTO THE REGION. SURFACE ANALYSIS SHOWS THE ARCTIC FRONT
ACROSS THE BLKHLS/WRN SD AREA WITH TEMPERATURES FALLING INTO THE
TEENS AND 20S THROUGH THE DAY. KUDX RADAR SHOWS SNOW FALLING ACROSS
THE NRN BLKHLS AND SURROUNDING AREAS.

SHORT RANGE MODELS SUGGEST UPSLOPE ENHANCEMENT OF SNOWFALL ACROSS
THE NRN BLKHLS WILL CONTINUE INTO THIS EVENING AS COLDER AIR
CONTINUES TO FILTER IN. QPF WILL BE LESS THAN WHAT WAS SEEN THIS
MORNING...BUT SNOW RATIOS WILL ALSO INCREASE...SO STILL THINK THE
NRN HILLS COULD SEE AN ADDITIONAL 1 TO 4 INCHES. WITH THE LULL IN
THE PRECIP EARLY THIS AFTERNOON...NOT MORE THAN A COUPLE INCHES OF
ADDITIONAL ACCUMULATION HAS OCCURRED SINCE THE LATE MORNING
REPORTS OF 4 TO 6 INCHES. WILL CONTINUE WITH 6 TO 12 INCH WORDING
FOR THE NRN HILLS...AND 3 TO 6 INCHES IN THE ADVISORY LOCATIONS.
ELSEWHERE ACROSS NE WY..GENERALLY 1 TO 4 INCHES IS EXPECTED. SNOW
WILL GRADUALLY END THROUGH THE LATE NIGHT HOURS. WIND HAS NOT BEEN
AN ISSUE TODAY...SO WILL CANCEL THE WIND ADVISORY WITH THE
FORECAST PACKAGE. TEMPS TONIGHT WILL DROP TO 5 BELOW TO 10 ABOVE
ZERO...WITH THE COLDEST TEMPS ACROSS NW TO CNTRL SD. WITH 5-10KT
WINDS EXPECTED OVERNIGHT...WIND CHILLS ARE EXPECTED TO DROP TO 10
BELOW TO 20 BELOW ZERO.

STRONG 1044MB ARCTIC HIGH WILL MOVE SOUTH INTO THE NRN PLAINS
THURSDAY. PRECIP WILL END BY TOMORROW MORNING...BUT SOME LINGERING
SHSN MAY OCCUR ACROSS THE SRN BLKHLS AND ADJACENT PLAINS. OTHERWISE
CLOUDS WILL DECREASE THROUGH THE DAY WITH HIGHS GENERALLY IN THE
TEENS. SKIES WILL CLEAR OUT THU NIGHT WITH LOWS 5 BELOW TO 5 ABOVE
ZERO.

.LONG TERM...FRIDAY THROUGH WEDNESDAY
ISSUED AT 246 PM MST WED FEB 25 2015

NORTHERLY FLOW WILL LEAD TO MUCH COLDER THAN AVERAGE TEMPERATURES
FROM FRIDAY THROUGH THE WEEKEND AS COLD AND DRY SURFACE HIGH
PRESSURE SETTLES OVER THE AREA. THE SURFACE HIGH WILL MOVE OFF TO
THE EAST ON MONDAY AS THE UPPER FLOW BECOMES MORE WESTERLY AND
WARMER PACIFIC SOURCED AIR PUSHES INTO THE NORTHERN PLAINS.
ALTHOUGH MODELS AGREE ON A BRIEF WARMUP MONDAY...THE GFS BRINGS IN
THE NEXT TROUGH/COLD FRONT FASTER AND KEEPS THE AREA COOLER THAN
THE ECMWF. THE GFS ALSO HAS AN EARLIER BATCH OF SNOW SPREADING
ACROSS SD MONDAY/MONDAY NIGHT WITH THE INITIAL FAST-MOVING
SHORTWAVE. THE ECMWF IS TRENDING SLOWER...KEEPING WARM AIR AROUND
INTO TUESDAY AND NOW WAITING UNTIL WEDNESDAY TO BRING IN PRECIP.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 907 PM MST WED FEB 25 2015

IFR/MVFR CIGS/VSBYS WILL SINK SOUTH THROUGH THURSDAY MORNING WITH
VFR CONDITIONS DEVELOPING BEHIND AS DRIER AIR FILTERS IN. LIFR
CONDITIONS WILL LINGER OVER THE HIGHER TERRAIN THROUGH ABOUT 09Z.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MST TONIGHT FOR SDZ025-
     072.

     WINTER STORM WARNING UNTIL MIDNIGHT MST TONIGHT FOR SDZ024.

WY...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MST TONIGHT FOR WYZ057.

&&

$$

UPDATE...HELGESON
SHORT TERM...13
LONG TERM...POJORLIE
AVIATION...HELGESON





000
FXUS63 KUNR 260411
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
911 PM MST WED FEB 25 2015

.UPDATE...
ISSUED AT 907 PM MST WED FEB 25 2015

LATEST RADAR TRENDS AND 00Z GUIDANCE SHOW -SN WINDING DOWN AS
FORCING SHIFTS SOUTH...BOUNDARY LAYER STARTS TO DRY OUT...AND
SUBSIDENCE STARTS TO KICK IN COURTESY OF 1042MB ARCTIC HIGH NOSING
INTO THE DAKOTAS.

WILL ALLOW HEADLINES TO EXPIRE ON SCHEDULE AT MIDNIGHT GIVEN -SN
STILL OCCURRING AND ROADS MESSY IN PLACES.

UPDATE ISSUED AT 405 PM MST WED FEB 25 2015

RECENT STORM REPORTS SHOWED AROUND AN INCH OF SNOW OVER PORTIONS
OF NORTHWEST SD. LATEST RADAR LOOP SHOWED -SN CONTINUING OVER
THESE AREAS AT LEAST INTO THE EARLY EVENING HOURS...SO HAVE
UPDATED TO RAISE POPS CONSIDERABLY...BUT THINGS STILL LOOK LIKE
THEY WILL TAPER OFF LATER THIS EVENING.

&&

.SHORT TERM...THIS EVENING THROUGH THURSDAY NIGHT
ISSUED AT 246 PM MST WED FEB 25 2015

UPPER AIR ANALYSIS SHOWS A BROAD UPPER TROUGH ACROSS THE ERN TWO
THIRDS OF THE CWA WITH NW FLOW CONTINUING ACROSS THE NRN PLAINS.
SEVERAL EMBEDDED SHORTWAVES ARE PUSHING THROUGH THE CANADIAN HIGH
PLAINS INTO THE REGION. SURFACE ANALYSIS SHOWS THE ARCTIC FRONT
ACROSS THE BLKHLS/WRN SD AREA WITH TEMPERATURES FALLING INTO THE
TEENS AND 20S THROUGH THE DAY. KUDX RADAR SHOWS SNOW FALLING ACROSS
THE NRN BLKHLS AND SURROUNDING AREAS.

SHORT RANGE MODELS SUGGEST UPSLOPE ENHANCEMENT OF SNOWFALL ACROSS
THE NRN BLKHLS WILL CONTINUE INTO THIS EVENING AS COLDER AIR
CONTINUES TO FILTER IN. QPF WILL BE LESS THAN WHAT WAS SEEN THIS
MORNING...BUT SNOW RATIOS WILL ALSO INCREASE...SO STILL THINK THE
NRN HILLS COULD SEE AN ADDITIONAL 1 TO 4 INCHES. WITH THE LULL IN
THE PRECIP EARLY THIS AFTERNOON...NOT MORE THAN A COUPLE INCHES OF
ADDITIONAL ACCUMULATION HAS OCCURRED SINCE THE LATE MORNING
REPORTS OF 4 TO 6 INCHES. WILL CONTINUE WITH 6 TO 12 INCH WORDING
FOR THE NRN HILLS...AND 3 TO 6 INCHES IN THE ADVISORY LOCATIONS.
ELSEWHERE ACROSS NE WY..GENERALLY 1 TO 4 INCHES IS EXPECTED. SNOW
WILL GRADUALLY END THROUGH THE LATE NIGHT HOURS. WIND HAS NOT BEEN
AN ISSUE TODAY...SO WILL CANCEL THE WIND ADVISORY WITH THE
FORECAST PACKAGE. TEMPS TONIGHT WILL DROP TO 5 BELOW TO 10 ABOVE
ZERO...WITH THE COLDEST TEMPS ACROSS NW TO CNTRL SD. WITH 5-10KT
WINDS EXPECTED OVERNIGHT...WIND CHILLS ARE EXPECTED TO DROP TO 10
BELOW TO 20 BELOW ZERO.

STRONG 1044MB ARCTIC HIGH WILL MOVE SOUTH INTO THE NRN PLAINS
THURSDAY. PRECIP WILL END BY TOMORROW MORNING...BUT SOME LINGERING
SHSN MAY OCCUR ACROSS THE SRN BLKHLS AND ADJACENT PLAINS. OTHERWISE
CLOUDS WILL DECREASE THROUGH THE DAY WITH HIGHS GENERALLY IN THE
TEENS. SKIES WILL CLEAR OUT THU NIGHT WITH LOWS 5 BELOW TO 5 ABOVE
ZERO.

.LONG TERM...FRIDAY THROUGH WEDNESDAY
ISSUED AT 246 PM MST WED FEB 25 2015

NORTHERLY FLOW WILL LEAD TO MUCH COLDER THAN AVERAGE TEMPERATURES
FROM FRIDAY THROUGH THE WEEKEND AS COLD AND DRY SURFACE HIGH
PRESSURE SETTLES OVER THE AREA. THE SURFACE HIGH WILL MOVE OFF TO
THE EAST ON MONDAY AS THE UPPER FLOW BECOMES MORE WESTERLY AND
WARMER PACIFIC SOURCED AIR PUSHES INTO THE NORTHERN PLAINS.
ALTHOUGH MODELS AGREE ON A BRIEF WARMUP MONDAY...THE GFS BRINGS IN
THE NEXT TROUGH/COLD FRONT FASTER AND KEEPS THE AREA COOLER THAN
THE ECMWF. THE GFS ALSO HAS AN EARLIER BATCH OF SNOW SPREADING
ACROSS SD MONDAY/MONDAY NIGHT WITH THE INITIAL FAST-MOVING
SHORTWAVE. THE ECMWF IS TRENDING SLOWER...KEEPING WARM AIR AROUND
INTO TUESDAY AND NOW WAITING UNTIL WEDNESDAY TO BRING IN PRECIP.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 907 PM MST WED FEB 25 2015

IFR/MVFR CIGS/VSBYS WILL SINK SOUTH THROUGH THURSDAY MORNING WITH
VFR CONDITIONS DEVELOPING BEHIND AS DRIER AIR FILTERS IN. LIFR
CONDITIONS WILL LINGER OVER THE HIGHER TERRAIN THROUGH ABOUT 09Z.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MST TONIGHT FOR SDZ025-
     072.

     WINTER STORM WARNING UNTIL MIDNIGHT MST TONIGHT FOR SDZ024.

WY...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MST TONIGHT FOR WYZ057.

&&

$$

UPDATE...HELGESON
SHORT TERM...13
LONG TERM...POJORLIE
AVIATION...HELGESON





000
FXUS63 KUNR 260411
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
911 PM MST WED FEB 25 2015

.UPDATE...
ISSUED AT 907 PM MST WED FEB 25 2015

LATEST RADAR TRENDS AND 00Z GUIDANCE SHOW -SN WINDING DOWN AS
FORCING SHIFTS SOUTH...BOUNDARY LAYER STARTS TO DRY OUT...AND
SUBSIDENCE STARTS TO KICK IN COURTESY OF 1042MB ARCTIC HIGH NOSING
INTO THE DAKOTAS.

WILL ALLOW HEADLINES TO EXPIRE ON SCHEDULE AT MIDNIGHT GIVEN -SN
STILL OCCURRING AND ROADS MESSY IN PLACES.

UPDATE ISSUED AT 405 PM MST WED FEB 25 2015

RECENT STORM REPORTS SHOWED AROUND AN INCH OF SNOW OVER PORTIONS
OF NORTHWEST SD. LATEST RADAR LOOP SHOWED -SN CONTINUING OVER
THESE AREAS AT LEAST INTO THE EARLY EVENING HOURS...SO HAVE
UPDATED TO RAISE POPS CONSIDERABLY...BUT THINGS STILL LOOK LIKE
THEY WILL TAPER OFF LATER THIS EVENING.

&&

.SHORT TERM...THIS EVENING THROUGH THURSDAY NIGHT
ISSUED AT 246 PM MST WED FEB 25 2015

UPPER AIR ANALYSIS SHOWS A BROAD UPPER TROUGH ACROSS THE ERN TWO
THIRDS OF THE CWA WITH NW FLOW CONTINUING ACROSS THE NRN PLAINS.
SEVERAL EMBEDDED SHORTWAVES ARE PUSHING THROUGH THE CANADIAN HIGH
PLAINS INTO THE REGION. SURFACE ANALYSIS SHOWS THE ARCTIC FRONT
ACROSS THE BLKHLS/WRN SD AREA WITH TEMPERATURES FALLING INTO THE
TEENS AND 20S THROUGH THE DAY. KUDX RADAR SHOWS SNOW FALLING ACROSS
THE NRN BLKHLS AND SURROUNDING AREAS.

SHORT RANGE MODELS SUGGEST UPSLOPE ENHANCEMENT OF SNOWFALL ACROSS
THE NRN BLKHLS WILL CONTINUE INTO THIS EVENING AS COLDER AIR
CONTINUES TO FILTER IN. QPF WILL BE LESS THAN WHAT WAS SEEN THIS
MORNING...BUT SNOW RATIOS WILL ALSO INCREASE...SO STILL THINK THE
NRN HILLS COULD SEE AN ADDITIONAL 1 TO 4 INCHES. WITH THE LULL IN
THE PRECIP EARLY THIS AFTERNOON...NOT MORE THAN A COUPLE INCHES OF
ADDITIONAL ACCUMULATION HAS OCCURRED SINCE THE LATE MORNING
REPORTS OF 4 TO 6 INCHES. WILL CONTINUE WITH 6 TO 12 INCH WORDING
FOR THE NRN HILLS...AND 3 TO 6 INCHES IN THE ADVISORY LOCATIONS.
ELSEWHERE ACROSS NE WY..GENERALLY 1 TO 4 INCHES IS EXPECTED. SNOW
WILL GRADUALLY END THROUGH THE LATE NIGHT HOURS. WIND HAS NOT BEEN
AN ISSUE TODAY...SO WILL CANCEL THE WIND ADVISORY WITH THE
FORECAST PACKAGE. TEMPS TONIGHT WILL DROP TO 5 BELOW TO 10 ABOVE
ZERO...WITH THE COLDEST TEMPS ACROSS NW TO CNTRL SD. WITH 5-10KT
WINDS EXPECTED OVERNIGHT...WIND CHILLS ARE EXPECTED TO DROP TO 10
BELOW TO 20 BELOW ZERO.

STRONG 1044MB ARCTIC HIGH WILL MOVE SOUTH INTO THE NRN PLAINS
THURSDAY. PRECIP WILL END BY TOMORROW MORNING...BUT SOME LINGERING
SHSN MAY OCCUR ACROSS THE SRN BLKHLS AND ADJACENT PLAINS. OTHERWISE
CLOUDS WILL DECREASE THROUGH THE DAY WITH HIGHS GENERALLY IN THE
TEENS. SKIES WILL CLEAR OUT THU NIGHT WITH LOWS 5 BELOW TO 5 ABOVE
ZERO.

.LONG TERM...FRIDAY THROUGH WEDNESDAY
ISSUED AT 246 PM MST WED FEB 25 2015

NORTHERLY FLOW WILL LEAD TO MUCH COLDER THAN AVERAGE TEMPERATURES
FROM FRIDAY THROUGH THE WEEKEND AS COLD AND DRY SURFACE HIGH
PRESSURE SETTLES OVER THE AREA. THE SURFACE HIGH WILL MOVE OFF TO
THE EAST ON MONDAY AS THE UPPER FLOW BECOMES MORE WESTERLY AND
WARMER PACIFIC SOURCED AIR PUSHES INTO THE NORTHERN PLAINS.
ALTHOUGH MODELS AGREE ON A BRIEF WARMUP MONDAY...THE GFS BRINGS IN
THE NEXT TROUGH/COLD FRONT FASTER AND KEEPS THE AREA COOLER THAN
THE ECMWF. THE GFS ALSO HAS AN EARLIER BATCH OF SNOW SPREADING
ACROSS SD MONDAY/MONDAY NIGHT WITH THE INITIAL FAST-MOVING
SHORTWAVE. THE ECMWF IS TRENDING SLOWER...KEEPING WARM AIR AROUND
INTO TUESDAY AND NOW WAITING UNTIL WEDNESDAY TO BRING IN PRECIP.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 907 PM MST WED FEB 25 2015

IFR/MVFR CIGS/VSBYS WILL SINK SOUTH THROUGH THURSDAY MORNING WITH
VFR CONDITIONS DEVELOPING BEHIND AS DRIER AIR FILTERS IN. LIFR
CONDITIONS WILL LINGER OVER THE HIGHER TERRAIN THROUGH ABOUT 09Z.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MST TONIGHT FOR SDZ025-
     072.

     WINTER STORM WARNING UNTIL MIDNIGHT MST TONIGHT FOR SDZ024.

WY...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MST TONIGHT FOR WYZ057.

&&

$$

UPDATE...HELGESON
SHORT TERM...13
LONG TERM...POJORLIE
AVIATION...HELGESON




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