599
FXUS65 KCYS 111026
AFDCYS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
426 AM MDT TUE MAR 11 2025
KEY MESSAGES
- WARM, DRY, AND BREEZY WEATHER WILL CONTINUE THROUGH THURSDAY
WITH ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS EACH
AFTERNOON.
- THE NEXT STORM SYSTEM WILL ARRIVE LATE THURSDAY INTO EARLY
SATURDAY, BRINGING STRONG WINDS AND A CHANCE FOR
PRECIPITATION. SOME SNOW ACCUMULATIONS ARE STILL POSSIBLE FOR
PARTS OF THE AREA.
SHORT TERM /THROUGH WEDNESDAY NIGHT/
ISSUED AT 426 AM MDT TUE MAR 11 2025
ZONAL FLOW ALOFT AS WE SLOWLY REBOUND FROM THE COLD
FRONT THAT PUSHED THROUGH EARLIER TONIGHT. THERE IS A SMALL JET OF
40-50KNOTS AT THE 700MB LEVEL SO TODAY LOOKS TO BE A LITTLE BREEZY
WITH WIND GUSTS UP 30-35 MPH IN THE AFTERNOON. IT WILL ALSO BE
FAIRLY DRY AS RH VALUES ARE EXPECTED TO DROP INTO THE LOW TO MID
TEENS EAST OF I-25. THIS AFTERNOON WE WILL BE ELEVATED FIRE WEATHER
CONDITIONS WITH THOSE LOW RH VALUES. THERE IS A LOT OF RISING MOTION
OVER WHERE WE ARE EXPECTING THESE LOW RH VALUES SO CONFIDENCE IS
LOWERED AS BE ABLE TO MIX DOWN THOSE STRONGER WIND GUST TO PUSH US
INTO THE CRITICAL FIRE WEATHER CRITERIA. WEDNESDAY, THE DRY AIR WILL
CONTINUE AS RH VALUES TO CONTINUE TO BE AT OR NEAR 15 PERCENT BUT
THE WINDS ALSO LOOK TO BE FAIRLY WEAK OVER THE PANHANDLE AHEAD OF
THE SYSTEM.
LONG TERM /THURSDAY THROUGH MONDAY/
ISSUED AT 426 AM MDT TUE MAR 11 2025
THE LONG TERM BEGINS RELATIVELY QUIET, BUT WE'LL SEE THIS
QUICKLY CHANGE AS A DEEP AND STACKED SYSTEM MOVES ACROSS THE
REGION BRINGING STRONG WINDS AND AREAS OF PRECIPITATION.
THANKFULLY, WITH THE SPEED OF THIS LOW WE SHOULDN'T EXPERIENCE A
LONG ENOUGH DURATION OF STRONG IMPACTS TO DO ANYTHING OUTSIDE OF
BRING US OUR USUAL WINDY CONDITIONS ALONGSIDE AREAS OF RAIN
MIXING INTO SNOW WITH COOLER TEMPERATURES, DEPARTING QUICKLY
INTO THE EARLY WEEKEND TIMEFRAME.
BEGINNING WEDNESDAY NIGHT, WE'LL SEE A QUICK TRANSIENT RIDGE
MOVING ACROSS THE CWA, BRINGING ANOTHER ROUND OF MOSTLY BENIGN
CONDITIONS WITH MILD TEMPERATURES SIMILAR TO TUESDAY AND
WEDNESDAY. BUT A BROAD TROUGH BEGINS TO MOVE INLAND ACROSS THE
WEST COAST AS WELL, AND BY FRIDAY MORNING WE'LL SEE A DEEPENING
SURFACE LOW ACROSS COLORADO THAT WILL THEN CONTINUE EASTWARDS
ACROSS THE CENTRAL PLAINS AND UP INTO THE GREAT LAKES OVER THE
WEEKEND. THE QUICK MOVING NATURE OF THIS SYSTEM WILL BE OUR
SAVING GRACE AND SHOULD HELP TO ABATE MORE SIGNIFICANT IMPACTS.
FOR PRECIPITATION: LOOK FOR PRECIP TO FIRST MOVE INTO THE
WESTERN MOUNTAINS OF THE CWA THURSDAY EVENING, WITH WIDESPREAD
RAIN AND SNOW MIXING IN THEN FRIDAY MORNING THROUGH THE
AFTERNOON. MOISTURE RETURN WILL BE FAIR, WITH PWAT ANOMALIES
SHOWING AROUND 150% OF NORMAL WITH VALUES AROUND 0.3-0.5 INCH;
THAT BEING SAID, FORCING SWEEPS VERY QUICKLY THROUGH, AND BY
FRIDAY EVENING MOST OF THE PRECIP WILL HAVE PUSHED THROUGH ASIDE
FROM LINGERING MOUNTAIN QPF. ALSO, HIGHS ARE STILL EXPECTED TO
REACH INTO THE 30'S AND 40'S WITH THE PANHANDLE WELL INTO THE
40'S, AND SNOW RATIOS WILL BE QUITE LOW, WELL BELOW 10-1, NOT TO
MENTION WARM GROUND TEMPERATURES THANKS TO THIS WEEK'S EARLY
MILD TEMPERATURES. AT BEST WE'RE LIKELY LOOKING AT A DUSTING TO
AN INCH FOR MOST LOCATIONS OUTSIDE OF CARBON AND ALBANY
COUNTIES, AND EVEN HERE THE BULK OF THE ACTIVITY WILL BE
RELEGATED TO THE MOUNTAINS, WITH THE NBM PRESENTING A 25%
PROBABILITY FOR AN INCH OR MORE OUTSIDE OF THE MOUNTAINS. THIS
LEADS TO THE SYSTEM BEING UNLIKELY TO PRODUCE WINTER WEATHER
HEADLINES OUTSIDE OF THE MOUNTAINS, AND EVEN HERE WE'RE
CURRENTLY ONLY SEEING ADVISORY LEVEL SNOWFALL AT BEST. FOR
WINDS: UNSURPRISINGLY A SYSTEM THIS DEEP WILL HAVE A STOUT
PRESSURE GRADIENT WITH A STRONG LOW-LEVEL JET ACCOMPANYING. AT
700 MB THE NORTHERLY JET IS MAXING AROUND 50-65 KNOTS ON FRIDAY
ON THE BACKSIDE OF THIS LOW, AND WITH MOSTLY FAVORABLE DOWNWARD
OMEGA VALUES, LOOK FOR THESE WINDS TO LIKELY MIX DOWN, LEADING
TO WIDESPREAD HIGH WIND CONCERNS. OF COURSE IF WE DO RECEIVE ANY
SNOW, LIMITED TO VERY LOW VISIBILITY CONCERNS WILL BE POSSIBLE
WITH THESE WINDS, BUT WITH SNOW NOT EXPECTED TO BE VERY HEAVY,
NOT LOOKING AT BLIZZARD LEVEL CONDITIONS AT THIS TIME.
CONDITIONS WILL EASE SATURDAY, AND BY THE EVENING TIMEFRAME
GUSTY CONDITIONS WILL BE TEMPERED AND PRECIPITATION OUT OF THE
REGION. ANOTHER TRANSIENT RIDGE TAKES THE PLACE OF THIS SYSTEM,
WHICH WILL BRING WARMING AND CLEARING CONDITIONS THAT WILL LEAD
BACK TO MORE WARMTH IN THE 50'S AND 60'S BY MONDAY, BUT ANOTHER
INCOMING TROUGH WILL QUICKLY COOL US BACK OFF AS RAIN, SNOW, AND
GUSTY CONDITIONS RETURN TO END THE LONG-TERM PERIOD.
AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/
ISSUED AT 426 AM MDT TUE MAR 11 2025
BREEZY CONDITIONS EXPECTED ONCE AGAIN TODAY WITH GUSTS AROUND 25
KNOTS MOST TERMINALS ACCOMPANIED BY HIGH CLOUDS TO CLEAR SKIES
LEADING TO WIDESPREAD VFR CONDITIONS.
CYS WATCHES/WARNINGS/ADVISORIES
WY...NONE.
NE...NONE.
SHORT TERM...MM
LONG TERM...CG
AVIATION...CG
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