937
FXUS65 KCYS 142119
AFDCYS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
319 PM MDT SAT MAR 14 2026
KEY MESSAGES
- STRONG WESTERLY WINDS AND CRITICAL FIRE DANGER WILL CONTINUE
THROUGH EARLY SATURDAY EVENING.
- A STRONG COLD FRONT SATURDAY EVENING WILL BRING MUCH COLDER
TEMPERATURES AND A QUICK ROUND OF LOCALLY HEAVY SNOW SHOWERS,
WITH POTENTIAL FOR WIDESPREAD LIGHT ACCUMULATIONS.
- STRONG NORTHWEST TO NORTH WINDS WILL CONTINUE OVER THE HIGH
PLAINS INTO SUNDAY, PRODUCING SUB-ZERO WIND CHILL
TEMPERATURES.
- RECORD BREAKING WARM TEMPERATURES ARE EXPECTED TO RETURN TO
THE FORECAST FOR THE SECOND HALF OF THE WEEK AHEAD.
SHORT TERM /THROUGH SUNDAY NIGHT/
ISSUED AT 300 PM MDT SAT MAR 14 2026
WIDESPREAD STRONG WINDS CONTINUE ACROSS THE AREA TODAY, BUT BIG
CHANGES ARE JUST AROUND THE CORNER. UNFORTUNATELY, THESE CHANGES
WILL NOT MEAN LESS WIND, JUST A FLIP TO A MUCH COLDER NORTHERLY WIND
INSTEAD OF THE WARM WESTERLY WIND. TODAY'S WIND IS MOSTLY PROCEEDING
AS EXPECTED, ALTHOUGH THE WESTERLIES WERE A LITTLE SLOWER THAN
EXPECTED TO PUSH THE SHALLOW, COOL AIRMASS OUT OF THE HIGH PLAINS
THIS MORNING. WIDESPREAD GUSTS OF 50 TO 70 MPH ARE BEING OBSERVED
OVER SOUTHEAST WYOMING THIS AFTERNOON. WIND GUSTS UP TO AROUND 80
MPH ARE SHOWING UP IN THE TYPICAL AREAS AS WELL. CLOUD COVER HAS
BEEN ON THE INCREASE AS A POWERFUL PACIFIC TROUGH APPROACHES THE
AREA. THIS SYSTEM WILL BE CARRYING A VERY STRONG COLD FRONT ALONG
WITH IT. CURRENT OBSERVATIONS PUT THE FRONT AROUND A BUFFALO TO
GILLETTE TO RAPID CITY LINE NOW. THIS WILL RACE SOUTHWARD OVER THE
AFTERNOON AND EVENING, REACHING DOUGLAS AND GLENROCK AROUND 7-8PM,
AND THEN THE I-80 CORRIDOR BETWEEN 10PM AND MIDNIGHT. THIS FRONT
WILL HAVE SEVERAL IMPACTS, INCLUDING MORE WIND, SNOW, AND COLD
TEMPERATURES. WE'LL BREAK DOWN EACH BELOW.
WIND: A NARROW, MORE POWERFUL 700-MB JET WILL PUSH SOUTHWARD JUST
AHEAD OF THE FRONTAL BOUNDARY, SO WE MAY SEE WINDS PEAK LATER THIS
AFTERNOON OR EARLY EVENING, JUST BEFORE THE WIND DIRECTION CHANGES.
A FEW GUSTS IN THE 80 TO 90 MPH RANGE CANNOT BE RULED OUT DURING
THIS PERIOD IN THE WIND PRONE AREAS. TEMPERATURES WILL PLUMMET
QUICKLY BEHIND THE FRONT, BY PERHAPS 15-20F IN A HALF HOUR OR SO.
WINDS WILL ALSO SUDDENLY SHIFT TO THE NORTH OR NORTHWEST. THE
FRONTAL BOUNDARY ITSELF COULD PUSH SOME GUSTS IN THE 60 TO 70 MPH
RANGE, BUT THIS SHOULD DROP BACK TO AROUND A MORE CONSISTENT 45 TO
60 MPH LATER TONIGHT OVER THE HIGH PLAINS. A FEW HOURS AFTER THE
FRONTAL PASSAGE, THE THREAT FOR HIGH WINDS WILL DECREASE IN CARBON
AND ALBANY COUNTIES. THESE HIGH WIND WARNINGS SHOULD BE ABLE TO
EXPIRE ON TIME. ALONG AND EAST OF THE LARAMIE RANGE, A VERY STRONG
PRESSURE GRADIENT WILL KEEP ELEVATED TO HIGH WINDS IN PLACE THROUGH
SUNDAY MORNING. CONFIDENCE ISN'T ALL THAT HIGH IN REACHING 60+MPH
CONSISTENTLY, BUT THE PROBABILITY OF AT LEAST A FEW GUSTS EXCEEDING
THIS CRITERIA IS HIGH ENOUGH TO WARRANT UPGRADING ALL REMAINING HIGH
WIND WATCHES. THE PRESSURE GRADIENT WILL BEGIN TO WEAKEN LATE SUNDAY
MORNING THROUGH THE AFTERNOON, AND WE SHOULD BE ABLE TO ENJOY
PERHAPS 12-18 HOURS WITHOUT ANY HIGH WIND HEADLINES IN AFFECT FOR
THE AREA.
SNOW: A NARROW PLUME OF ELEVATED MOISTURE WILL PUSH THROUGH THE AREA
WITH TONIGHT'S COLD FRONT. EXTRACTING THIS MOISTURE WILL BE SOMEWHAT
DIFFICULT, AS MODELS SHOW CLEAR, STRONG NEGATIVE THETA-E ADVECTION
BEHIND THE FRONT. HOWEVER, STRONG FRONTOGENESIS AND MECHANICAL
FORCING CAUSED BY RAPID SURFACE PRESSURE RISES, WITH A LITTLE BOOST
FROM FAVORABLE JET STREAK DYNAMICS AND QG ASCENT. THIS WILL ALLOW
FOR A SHORT WINDOW FOR FAIRLY GOOD FORCING. INSTABILITY AND STEEP
LAPSE RATES WILL ALSO BE PRESENT ALONG THE FRONT, SO SOME SNOW
SHOWERS COULD TAKE ON CONVECTIVE CHARACTERISTICS. PRECIPITATION
RATES WILL BE HEAVY AT TIMES, AND WHEN COMBINED WITH THE PLUMMETING
TEMPERATURES AND STRONG WINDS, WE COULD SEE SOME AREAS REACHING THE
CRITERIA FOR SNOW SQUALLS. WHILE SCATTERED SNOW SHOWERS WILL
CONTINUE THROUGH THE NIGHT AND INTO SUNDAY MORNING, THE SNOW SQUALL
POTENTIAL SHOULD BE CONCLUDED BY AROUND MIDNIGHT AS THE BEST
FRONTOGENESIS AND MECHANICAL FORCING PUSHES SOUTH AND EAST. OVERALL
ACCUMULATIONS ARE FAIRLY MODEST DUE TO THE BRIEF NATURE OF THIS
EVENT. HOWEVER, IMPACTS COULD BE HIGHER THAN YOUR TYPICAL LIGHT SNOW
EVENT DUE TO THE SNOWFALL RATES, WIND SPEEDS, AND TEMPERATURE DROP.
THEREFORE, THE WINTER WEATHER ADVISORY WAS EXPANDED TO INCLUDE
CONVERSE AND NIOBRARA COUNTIES, AND THE I-80 CORRIDOR NEAR
ARLINGTON/ELK MOUNTAIN. THESE AREAS HAVE THE HIGHEST CONFIDENCE IN
SEEING MORE THAN 1" OF SNOW, WHICH WILL PROBABLY CAUSE TRAVEL
IMPACTS AS IT BLOWS AROUND. WE WILL ALSO NEED TO WATCH THE LARAMIE
VALLEY, I-80 SUMMIT, AND THE REMAINING PINE RIDGE/US-20 CORRIDOR
TOWARDS CHADRON FOR POSSIBLE EXPANSIONS OF THE ADVISORY. ELSEWHERE,
LOOK FOR BETWEEN 0.5 AND 1.5" OF SNOW (THAT WILL BE VERY DIFFICULT
TO MEASURE WITH THE WIND).
SNOW SHOWERS MAY PICK UP IN COVERAGE AND INTENSITY AGAIN SUNDAY
AFTERNOON. BEHIND THIS SHORTWAVE TROUGH, MODELS SHOW A STRATOSPHERIC
INTRUSION PUSHING THE TROPOPAUSE DOWN TO AROUND 500 TO EVEN 600-MB.
IN FACT, 500-MB TEMPERATURES ARE PUSHING CLIMATOLOGICAL MINIMUMS PER
THE NAEFS MEAN, INDICATING UNUSUALLY COLD TEMPERATURES ALOFT. THAT
WILL LEAD TO STEEP LAPSE RATES, AND SHALLOW CONVECTIVE SNOW SHOWERS
SHOULD DEVELOP WITH WEAK DAYTIME SURFACE HEATING. THIS ACTIVITY
COULD BE LOCALLY INTENSE ONCE AGAIN. THE MAIN AREAS TO WATCH WILL BE
THE TYPICAL NORTHWEST FLOW LOW LEVEL LEE CONVERGENCE ZONES,
INCLUDING NORTHERN LARAMIE COUNTY/SOUTHERN PLATTE COUNTY (CONVERGING
IN THE LEE OF THE NORTHERN LARAMIE RANGE), AND DAWES COUNTY
(CONVERGING IN THE LEE OF THE BLACK HILLS). MODELS OFTEN UNDER-DO
THIS TYPE OF POST-STORM SYSTEM CONVECTIVE SNOW SHOWER ACTIVITY, SO
LATER SHIFTS MAY NEED TO NUDGE POPS UP AS CONFIDENCE IMPROVES LATER.
COLD: LASTLY, WE HAVE THE COLD TEMPERATURES. THIS WILL BE AN
UNUSUALLY COLD AIRMASS FOR MID-MARCH, ESPECIALLY SO CONSIDERING IT
WILL BE BOOKENDED BY NEAR RECORD WARMTH BOTH BEFORE AND AFTER. 700-
MB TEMPERATURES BOTTOM OUT AROUND -16 TO -20C ACROSS THE AREA, WHICH
WILL ACTUALLY BE CLOSE TO THE CLIMATOLOGICAL FIRST PERCENTILE. A VERY
COLD AIRMASS COMBINED WITH STRONG WINDS WILL PUSH WIND CHILLS WELL
BELOW ZERO FOR MUCH OF THE AREA BY SUNDAY MORNING. ACTUAL HIGH
TEMPERATURES WILL BE STUCK IN THE 20S FOR MOST OF THE AREA DURING
THE AFTERNOON. WHILE CLOUD COVER WILL START INCREASING FROM THE WEST
AGAIN SUNDAY NIGHT, WE SHOULD HAVE SEVERAL HOURS OF CLEAR SKIES THAT
WILL ALLOW FOR TEMPERATURES TO TAKE ANOTHER DIVE AS WINDS LIGHTEN
UP, ESPECIALLY FOR LARAMIE AND EASTWARD. MONDAY MAY START OFF IN THE
SINGLE DIGITS FOR MUCH OF THE AREA.
WARM AIR ADVECTION WILL RETURN TO THE AREA MONDAY AS THE SYNOPTIC
WEATHER PATTERN CONCLUDED ZONAL FLOW AND RETURNS TO THE WESTERN
RIDGE/EASTERN TROUGH CONFIGURATION. THE EXCEPTIONALLY STRONG WESTERN
RIDGE WILL BEGIN TO ENCROACH EASTWARD ON MONDAY, PUSHING HIGHS BACK
TO NEAR SEASONAL AVERAGES FOR MONDAY. AS WITH MOST WARM AIR
ADVECTION SETUPS, WE WILL NEED TO WATCH FOR GAP WINDS INCREASING
AGAIN TOO. THE ARLINGTON AREA HAS A 50 TO 60% OF HIGH WINDS
BEGINNING AROUND DAYBREAK MONDAY, BUT THE PROBABILITY FOR HIGH WINDS
IS LOWER ACROSS THE REST OF THE AREA.
LONG TERM /MONDAY THROUGH FRIDAY/
ISSUED AT 300 PM MDT SAT MAR 14 2026
ON TUESDAY, AN UPPER LEVEL RIDGE WILL BE PUSHING INTO
THE WESTERN COAST CENTERED NEAR THE CALIFORNIA\NEVADA BORDER. THE
INTERMOUNTAIN WEST WILL BE IN NORTHWEST FLOW WITH THE STRONGEST PART
OF THE JETSTREAM CENTERED OVER SOUTHEAST MONTANA AND THE DAKOTAS.
WITH A WEAK SHORTWAVE DIVING INTO THE NORTHERN RED RIVER VALLEY OUR
HEIGHT GRADIENT BECOMES COMPRESSED INTENSIFYING THE 700MB JET TO
GENERALLY AROUND 55-60 KNOTS WITH THE GFS HAVING A COUPLE BRIEF
INSTANCES OF ACCELERATIONS GREATER THAN 60. THE CRAIG TO CASPER
HEIGHT GRADIENT DIFFERENCE INCREASES FROM 50METERS TO 85METERS BY
THE AFTERNOON INCREASING OUR CONFIDENCE IN POTENTIAL HIGH WINDS FOR
TUESDAY. OUR IN-HOUSE HIGH WIND ALGORITHM PLACES HIGH CONFIDENCE IN
THE WIND PRONES HITTING HIGH WIND CRITERIA FROM 40 PERCENT TO 80/90
PERCENT BY NOON ON TUESDAY. AS THIS RIDGE SLOWLY APPROACHES THE FOUR
CORNERS REGION, THE JETSTREAM SHOULD BE SLOWLY PUSHING NORTH AS WELL
TAPERING OFF OUR WINDS THROUGHOUT THE DAY WEDNESDAY. LOOKING AT
CLUSTER ANALYSIS THERE IS SOME UNCERTAINTY IN THE TIMING OF THE
ARRIVAL OF THE RIDGE AS SOME MEMBERS OF THE GRAND ENSEMBLE HAVE IT
ARRIVING LATER AND LESS AMPLIFIED THAN OTHERS. A LATER AND LESS
AMPLIFIED RIDGE EQUATES TO THE EXTENSION OF THE HIGH WINDS THROUGH
THE END OF THE WEEK AS THE JETSTREAM WON'T BE PUSHED NORTH WITHOUT
THE AMPLIFIED RIDGE. IN WARMER NEWS, THIS RIDGE ALSO HAS THE MAKINGS
OF A FUN DEATH RIDGE BY THE MIDDLE TO END OF THE WEEK. MEANING 700MB
TEMPERATURES RISE BETWEEN 10 TO 14C AND SURFACE TEMPERATURES RISE
INTO THE 90 TO 99TH PERCENTILE LATER THIS WEEK DEPICTED BY NAEFS. TO
GIVE EVERYONE AN IDEA OF THE POTENTIAL MAGNITUDE OF THIS RIDGE. THE
HIGH WINDS LOOK TO POTENTIALLY STOP BY WEDNESDAY AFTERNOON/EVENING
AND THE HIGH TEMPERATURES START IN THE 30/40'S AT THE BEGINNING OF
THE WEEK AND END IN THE 70'S TO 80'S UPON THE ARRIVAL OF THIS RIDGE
WITH NO PRECIPITATION CHANCES AS WELL AFTER TUESDAY. SO THIS RIDGE
WILL BE SOMETHING TO KEEP AN EYE ON AS FIRE WEATHER CONCERNS LOOK TO
AMPLIFY AS WELL WITH THIS RIDGE.
AVIATION /18Z TAFS THROUGH 18Z SUNDAY/
ISSUED AT 1140 AM MDT SAT MAR 14 2026
WINDS ARE GOING TO BE RATHER GUSTY TODAY AS THE 700MB JET VERY
SLOWLY TAPERS OFF OVER THE NEXT 24HOURS AND THE MOUNTAIN WAVE
SLOWLY DISSIPATES. RIGHT NOW WE HAVE A MIX OF HIGH CLOUDS AND
ALMOST MID BASED CLOUDS FROM 12000 FT AND ABOVE. OVER THE DAY
CLOUDS ARE EXPECTED TO LOWER AS THE FRONT APPROACHES. ONCE
PRECIPITATION IS DROPPING THE CLOUDS ARE EXPECTED TO BE AROUND
1,000 TO 2,000FT BASED OFF SATELLITE WITH THE POSSIBILITY OF
CLOUDS LOWERING TO 500FT. JUDGING OFF SATELLITE CLOUDS MAY NOT
CLEAR OVER THE NEXT 36 HOURS BUT WE MAY BE ABLE TO SQUEEZE OUT
VFR CEILINGS AROUND 5,000 TO 8,000FT WITH SOME CLOUD HOLES TO
GIVE US FALSE HOPE. NO LOW LEVEL WIND SHEAR CONCERNS TONIGHT IF
THE 700MB JET TAPERS OFF LIKE ITS SUPPOSED TO.
CYS WATCHES/WARNINGS/ADVISORIES
WY...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR WYZ418-
430>433.
HIGH WIND WARNING UNTIL NOON MDT SUNDAY FOR WYZ101-102-106>108-
116>119.
WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 9 AM MDT
SUNDAY FOR WYZ101>103.
HIGH WIND WARNING UNTIL MIDNIGHT MDT TONIGHT FOR WYZ103>105-
109-113.
HIGH WIND WARNING UNTIL 3 AM MDT SUNDAY FOR WYZ110-115.
WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO 9 AM MDT
SUNDAY FOR WYZ110.
WINTER WEATHER ADVISORY UNTIL NOON MDT SUNDAY FOR WYZ114.
NE...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR NEZ435>437.
HIGH WIND WARNING FROM 8 PM THIS EVENING TO 3 PM MDT SUNDAY
FOR NEZ002-003-021-055.
HIGH WIND WARNING UNTIL 3 PM MDT SUNDAY FOR NEZ019-020-054-095-
096.
SHORT TERM...MN
LONG TERM...MM
AVIATION...MM
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