204
FXUS65 KCYS 080414
AFDCYS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
914 PM MST FRI MAR 7 2025
KEY MESSAGES
- SNOWFALL WILL TAPER OFF FRIDAY EVENING AS THE SYSTEM
CONTINUES TO EXIT EASTWARD.
- MILD AND DRY CONDITIONS EXPECTED TO START THIS WEEKEND WITH
THE RETURN OF WINDY CONDITIONS FOR SOUTHEAST WYOMING ON
MONDAY.
- THE NEXT PACIFIC STORM SYSTEM IS FORECAST TO MOVE ACROSS
WYOMING AT THE END OF NEXT WEEK.
SHORT TERM /THROUGH SUNDAY/
ISSUED AT 204 PM MST FRI MAR 7 2025
OBSERVATIONS AND RADAR STILL SHOW SOME LIGHT SNOW FALLING ACROSS THE
AREA THIS AFTERNOON. MOST WINTER STORM WARNINGS AND WINTER WEATHER
ADVISORIES HAVE EXPIRED AS THE HEAVIEST SNOW HAS SUBSIDED. DESPITE
THE SURFACE LOW BEING WELL OFF TO THE EAST, A LINGERING VORT MAX
OVER THE CWA WILL ALLOW THESE LIGHT SNOW SHOWERS TO CONTINUE
THROUGHOUT THE AFTERNOON. AS THE VORT MAX WEAKENS, SNOW SHOULD TAPER
OFF THIS EVENING, WITH SOME LINGERING SNOW SHOWERS STILL POSSIBLE IN
THE MOUNTAINS OVERNIGHT. ADDITIONAL SNOW ACCUMULATIONS THROUGHOUT
THE DAY WILL BE MINIMAL. HEADING INTO THE OVERNIGHT HOURS, SOME HI-
RES GUIDANCE IS HINTING AT THE POSSIBILITY OF FOG, MAINLY ALONG AND
WEST OF THE LARAMIE RANGE. WIND DIRECTION, ALTHOUGH WEAK, LOOKS
FAVORABLE FOR UPSLOPE FOG IN THE LARAMIE VALLEY AND SHIRLEY BASIN.
CANNOT RULE OUT FOG POTENTIAL IN OTHER SNOW COVERED AREAS, HOWEVER,
WIND DIRECTION DOES NOT LOOK FAVORABLE.
HEADING INTO THE WEEKEND, UPPER-LEVEL RIDGING WILL BUILD OVER THE
GREAT BASIN. THIS WILL ALLOW FOR WARMER AND DRIER WEATHER TO SETTLE
INTO THE REGION. WHILE TEMPERATURES ARE EXPECTED TO WARM RAPIDLY
OVER THE NEXT FEW DAYS DUE TO MUCH MILDER 700 MB TEMPERATURES, AREAS
WITH SNOWPACK MAY BE A LITTLE COOLER. DID DECIDED TO KEEP HIGHS
BELOW GUIDANCE IN AREAS WITH SNOWPACK, ESPECIALLY ALONG THE US-20
CORRIDOR WHERE THE HIGHEST SNOWFALL AMOUNTS HAVE BEEN REPORTED.
REGARDLESS, BY SUNDAY, MANY LOCATIONS WILL SEE THE RETURN OF ABOVE
AVERAGE TEMPERATURES WITH PLENTY OF MELTING SNOW. SUBSIDENCE UNDER
THE RIDGE WILL KEEP SKIES MOSTLY SUNNY WITH NO CHANCE OF
PRECIPITATION.
LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/
ISSUED AT 204 PM MST FRI MAR 7 2025
A VERY MILD PATTERN IS EXPECTED TO TAKE SHAPE NEXT WEEK. THE
MODELS AND ENSEMBLES ARE DEPICTING US GETTING SANDWICHED
BETWEEN THE POLAR LOW IN THE NORTHERN CANADA AND AN UPPER LEVEL
RIDGE IN THE DEEP SOUTH. THIS WILL SET THE STAGE FOR BREEZY AND
MILD CONDITIONS THROUGH MUCH OF THE WEEK. THE MODELS ARE ALSO
SHOWING A SUBTLE SHORTWAVE TRANSVERSING THROUGH THE NORTHERN
ROCKIES INTO THE NORTHERN PLAINS ON MONDAY INTO TUESDAY. AS A
RESULT, THIS WILL CAUSE THE HEIGHT/SURFACE GRADIENTS TO INCREASE
ACROSS THE WIND PRONE AREAS FROM SUNDAY NIGHT THROUGH MONDAY
BEFORE DIMINISHING ON MONDAY NIGHT. THERE IS ALSO A CHANCE THAT
SOME OF THESE STRONGER WINDS ALOFT MAY MIX DOWN ACROSS THE
WYOMING AND NEBRASKA PANHANDLE ON MONDAY, RESULTING IN SOME
GUSTY WINDS OF 40 TO 50 MPH. IN ADDITION, SEVERAL OF THE
DETERMINISTIC SOLUTIONS ARE SHOWING SOME MOUNTAIN WAVE ACTIVITY
ON SUNDAY NIGHT INTO MONDAY WHICH COULD ALLOW FOR SOME WAVE
BREAKS ESPECIALLY ON MONDAY MORNING. WE DID BUMP UP TEMPERATURES
A BIT ON MONDAY ESPECIALLY WITH THE MODELS SHOWING WELL ABOVE
NORMAL ANOMALIES WITH STANDARD DEVIATIONS AROUND +1 EAST OF THE
LARAMIE RANGE ACCORDING TO THE NAEFS WHERE DOWNSLOPE FLOW WILL
BE IN PLACE. WE COULD ALSO END UP HAVING SOME MILDER OVERNIGHT
LOWS AS WELL.
ON TUESDAY, A SLIGHT COOL DOWN IS EXPECTED WITH THE PASSAGE OF
A WEAK FRONTAL BOUNDARY. THIS BOUNDARY MAY COOL US OFF A TAD,
BUT TEMPERATURES WILL CONTINUE TO BE ON THE MILD SIDE AND NOT
QUITE AS WINDY AS MONDAY.
THE MILD REGIME IS EXPECTED TO CONTINUE ON WEDNESDAY AND
THURSDAY, BUT PERHAPS NOT QUITE AS WINDY AS MONDAY. HOWEVER,
WITH THE APPROACH OF THE UPPER LEVEL TROF MOVING IN FROM THE
PACIFIC WE COULD SEE SOME GUSTY SOUTHWEST WINDS DEVELOP ON THE
WESTERN FRINGES OF OUR FORECAST AREA AROUND RAWLINS AND MUDDY
GAP. SPEAKING OF THE UPPER LEVEL TROF, THIS TROF COULD END UP
BRINGING MUCH OF THE FORECAST AREA WITH A GOOD SHOT OF SNOWFALL
ON FRIDAY. AT THIS POINT, THE DETERMINISTIC MODELS/ENSEMBLES AND
CLUSTERS ARE IN PRETTY GOOD AGREEMENT OF THIS UPPER LEVEL TROF
TURNING INTO A CLOSED LOW BY SATURDAY SOMEWHERE OVER EASTERN
COLORADO, WESTERN KANSAS OR NEBRASKA PANHANDLE. STILL PLENTY OF
TIME TO EVALUATE THE EVOLUTION OF THIS SYSTEM, BUT CERTAINLY A
SYSTEM WORTH KEEPING OUR EYES ON.
AVIATION /06Z TAFS THROUGH 06Z SUNDAY/
ISSUED AT 912 PM MST FRI MAR 7 2025
NORTH FLOW ALOFT WILL CONTINUE. SKIES WILL BE MOSTLY CLEAR.
WINDS WILL REMAIN 14 KNOTS OR LESS.
CYS WATCHES/WARNINGS/ADVISORIES
WY...NONE.
NE...NONE.
SHORT TERM...SF
LONG TERM...TJT/REC
AVIATION...RUBIN
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