960
FXUS65 KCYS 051745
AFDCYS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1145 AM MDT SUN APR 5 2026
KEY MESSAGES
- A GORGEOUS WEEKEND IS IN STORE AS TEMPERATURES REBOUND INTO
THE UPPER 50S AND 60S WITH CLEARING SKIES AND MINIMAL
PRECIPITATION CHANCES.
- WARMER, DRIER WEATHER RETURNS FOR THE EARLY PART OF THE WEEK
AHEAD, WITH FIRE CONCERNS INCREASING AFTER MONDAY.
- MORE UNSETTLED WEATHER PATTERN MAY RETURN AS EARLY AS
WEDNESDAY AND CONTINUE INTO NEXT WEEKEND.
SHORT TERM /THROUGH TUESDAY/
ISSUED AT 230 AM MDT SUN APR 5 2026
QUIET WEATHER EXPECTED OVER THE NEXT 48 HOURS WITH MINIMAL
CHANCES FOR PRECIPITATION AND RELATIVELY LIGHT WINDS HEADING
INTO THE EARLY PART OF THE WORK-WEEK. CURRENT IR SATELLITE LOOP
SHOWS CLEAR SKIES OVER SOUTHEAST WYOMING AND WESTERN NEBRASKA
EARLY THIS MORNING WITH SURFACE OBSERVATIONS SHOWING
TEMPERATURES IN THE 20S TO LOW 30S. EXPECT LOW TEMPERATURES TO
BOTTOM-OUT CLOSE TO AVERAGE OR SLIGHTLY BELOW AVERAGE FOR THIS
TIME OF THE YEAR. OTHERWISE, SUNDAY WILL BE SIMILAR TO SATURDAY
WITH LITTLE TO NO CHANCE OF PRECIPITATION AND MOSTLY SUNNY
SKIES. IT WILL BE WARMER TODAY WITH HIGHS IN THE UPPER 50S TO
MIDDLE 60S, WARMEST OVER THE EASTERN HIGH PLAINS. OVERALL, A
PLEASANT EASTER SUNDAY IS EXPECTED.
MODELS SHOW THE UPPER LEVEL RIDGE AXIS ACROSS THE WESTERN US
DRIFTING EASTWARD INTO THE INTERMOUNTAIN WEST FOR EARLY NEXT
WEEK. THIS RIDGE AXIS IS EXPECTED TO WEAKEN AS IT NEARS THE
FRONT RANGE, MAINLY DUE TO THE STRENGTH OF THE LONG WAVE UPPER
LEVEL TROUGH ANCHORED OVER THE EASTERN UNITED STATES. THIS LONG
WAVE TROUGH IS EXPECTED TO BE CLOSE ENOUGH TO SENT A SHALLOW
BACK DOOR COLD FRONT SOUTHWARD ACROSS THE HIGH PLAINS LATER ON
MONDAY. EXPECT HIGH TEMPERATURES ON MONDAY TO BE A FEW DEGREES
COOLER THAN SUNDAY ALONG AND EAST OF THE INTERSTATE 25 CORRIDOR,
BUT REMAIN ABOVE AVERAGE FOR SARATOGA, LARAMIE, AND RAWLINS
SINCE THE COOLER AIR WILL BE SHALLOW ENOUGH NOT TO MAKE IT PAST
THE LARAMIE RANGE. ALL MODELS INDICATE A RELATIVELY STRONG POLAR
SURFACE HIGH PRESSURE CENTERED OVER THE DAKOTAS AND MOVING
SOUTHEAST THROUGH MONDAY EVENING. THIS WILL RESULT IN SURFACE
WINDS SHIFTING INTO THE EAST AND SOUTHEAST MONDAY AND MONDAY
NIGHT. AN AREA OF SURFACE CONVERGENCE IS EXPECTED TO DEVELOP
ALONG OR NEAR THE LARAMIE RANGE WITH A CONTINUATION OF WEST TO
SOUTHWEST WINDS OVER ALBANY AND CARBON COUNTIES. CAN'T RULE OUT
SOME AFTERNOON CONVECTION TRYING TO FORM OFF THE MOUNTAINS,
INCLUDING THE SNOWY RANGE, MONDAY AFTERNOON. HOWEVER, BOUNDARY
LAYER MOISTURE APPEARS LIMITED WITH MINIMAL CAPE BELOW 200 J/KG.
IN ADDITION, ANY VERTICAL DEVELOPMENT WILL BE LIMITED TO BELOW
18000 FEET DUE TO WARMER AIR ALOFT BASED ON AREA SOUNDINGS. KEPT
POP BELOW 15 PERCENT FOR NOW WITH LIMITED CONFIDENCE, AND EVEN
IF CONVECTION INITIATION BEGINS...LIGHT SHOWER ACTIVITY LOOKS
LIKE THE MOST LIKELY OUTCOME AT BEST.
FOR MONDAY NIGHT AND TUESDAY, MODELS SHOW A WEAK UPPER LEVEL
TROUGH DIVING THROUGH THE AREA. THIS LOOKS LIKE THE BEST CHANCE
FOR PRECIPITATION IN THE SHORT TERM BUT ENSEMBLES ARE SHOWING
MINIMAL COVERAGE AND QPF WITH THIS FEATURE, SO KEPT POP BELOW 25
PERCENT ACROSS WESTERN NEBRASKA FOR NOW. THIS TROUGH WILL ALSO
SHIFT WINDS INTO THE WEST WITH WINDY CONDITIONS RETURNING TO
SOUTHEAST WYOMING. TEMPERATURES SHOULD REBOUND DUE TO DOWNSLOPE
WESTERLY FLOW...WITH HIGHS IN THE 60S TO LOW 70S.
LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/
ISSUED AT 118 AM MDT SUN APR 5 2026
THE LONG TERM PERIOD WILL BEGIN UNDER ZONAL FLOW ALOFT AS A
VIGOROUS SHORTWAVE TROUGH LOCATED OVER MONTANA PASSES BY WELL TO
OUR NORTH. WEDNESDAY WILL BE THE WINDIEST DAY OF THE WEEK, AHEAD OF
A COLD FRONT THAT WILL SLIDE THROUGH SOUTHERN WYOMING AND WESTERN
NEBRASKA. WITH 35-40 KNOT CROSS-BARRIER 700 MB FLOW AND AN OMEGA
FIELD REFLECTIVE OF A MOUNTAIN WAVE PATTERN, BOTH NBM AND LREF
ENSEMBLE GUIDANCE ARE SUGGESTING WIND GUSTS OF 30-35 MPH ACROSS
SOUTHERN WYOMING, WITH SLIGHTLY CALMER CONDITIONS OVER OUR NEBRASKA
COUNTIES. FOR THE USUAL HIGH WIND HOT SPOTS, IN-HOUSE RANDOM FOREST
GUIDANCE HAS 40% PROBABILITIES OF EXCEEDING HIGH WIND CRITERIA AT
ARLINGTON, WITH PROBABILITIES BEING AROUND 20% FOR BORDEAUX. THE
LOCALLY HIGHER GUSTS IN BOTH OF THESE LOCATIONS ARE ALSO BEING
PICKED UP ON ENSEMBLE GUIDANCE WITH A DISTINCT MAXIMUM IN 90TH
PERCENTILE WIND GUSTS EXCEEDING 60 MPH WEST OF LARAMIE ALONG THE
SNOWY RANGE. THESE WINDY CONDITIONS WILL ALSO BE ACCOMPANIED BY HIGH
TEMPERATURES 5-10 DEGREES ABOVE CLIMATOLOGY IN THE AHEAD OF THE
FRONT, HOWEVER THE TIMING OF THE FROPA WILL ULTIMATELY DETERMINE HOW
WARM WE GET ON WEDNESDAY.
HEADING INTO THURSDAY, SOUTHERN WYOMING AND WESTERN NEBRASKA WILL BE
SITUATED IN THE RIGHT-ENTRANCE REGION OF A 70-80 KNOT 250 MB JET,
PROVIDING A SOURCE FOR LARGE-SCALE FORCING FOR ASCENT. MODEL
SOUNDINGS AND CROSS-SECTIONS SHOW STEEP, NEARLY DRY ADIABATIC 700-
500 MB LAPSE RATES, COMBINED WITH WEAK INSTABILITY (<100 J/KG
SBCAPE). AS PWAT IS PROGGED TO INCREASE TO 80-90TH PERCENTILE VALUES
RELATIVE TO CLIMATOLOGY ON THURSDAY, WE SHOULD SEE AN INCREASE IN
COVERAGE OF SHOWERS AND THUNDERSTORMS IN THE AFTERNOON AND EARLY
EVENING GIVEN THE COMBINATION OF MOISTURE, LIFT, AND INSTABILITY.
MOVING INTO FRIDAY AND THE WEEKEND, WE WILL REMAIN DOWNSTREAM OF A
RATHER AMPLIFIED SHORTWAVE TROUGH LOCATED OVER THE CENTRAL
CALIFORNIA COAST, PLACING US IN A SOUTHWESTERLY FLOW REGIME
RESULTING IN A BROAD FETCH OF MOISTURE AND PWAT > 90TH PERCENTILE
ACROSS OUR AREA. WITH NUMEROUS SUBTLE DISTURBANCES EMBEDDED IN THE
SOUTHWESTERLY FLOW COMBINED WITH ANOMALOUS MOISTURE, WE CAN EXPECT
DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS INTO THE WEEKEND AND
HIGH TEMPERATURES NEAR CLIMATOLOGY.
AVIATION /18Z TAFS THROUGH 18Z MONDAY/
ISSUED AT 1138 AM MDT SUN APR 5 2026
VFR CONDITIONS ARE EXPECTED FOR THE FORECAST PERIOD. WINDS TODAY
WILL GENERALLY BE LIGHT, BUT THE DIRECTION MAY BE VARIABLE AT
TIMES. THIS EVENING, A FRONTAL BOUNDARY WILL SLIP INTO THE AREA
FROM THE NORTHEAST, AND LEAD TO NORTHEAST WINDS IN NEBRASKA
WHICH WILL ROTATE TO EAST OR SOUTHEAST BY MONDAY MORNING. WINDS
SPEEDS WILL PICK UP MONDAY MORNING, OUT OF THE SW AT RWL, AND
OUT OF THE E OR ESE IN THE NEBRASKA PANHANDLE. EXPECT PERIODIC
MID TO HIGH LEVEL CLOUDS FILTERING THROUGH THE AREA THROUGH THE
ENTIRE TAF PERIOD.
CYS WATCHES/WARNINGS/ADVISORIES
WY...NONE.
NE...NONE.
SHORT TERM...TJT
LONG TERM...NB
AVIATION...MN
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