978
FXUS65 KCYS 130501
AFDCYS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1101 PM MDT FRI JUN 12 2026
KEY MESSAGES
- A COLD FRONT WILL SHIFT WINDS OVER THE HIGH PLAINS TO THE
NORTHEAST THIS EVENING. BREEZY NORTH TO NORTHEAST WINDS WILL
CONTINUE THROUGH SATURDAY.
- TEMPORARY RELIEF FROM THE CRITICAL FIRE WEATHER CONDITIONS
WILL COME THIS WEEKEND WITH COOLER TEMPERATURES AND SLIGHT
CHANCES FOR A FEW SHOWERS BOTH SATURDAY AND SUNDAY.
- FIRE WEATHER CONCERNS WILL ESCALATE ONCE AGAIN MONDAY THROUGH
WEDNESDAY.
SHORT TERM /THROUGH SUNDAY NIGHT/
ISSUED AT 300 PM MDT FRI JUN 12 2026
WE HAVE HARDLY A CLOUD IN THE SKY THIS AFTERNOON AS A VERY DRY
AIRMASS MOVES OVERHEAD. MOST OF THE AREA IS IN THE UPPER 70S TO 80S,
PUSHING RELATIVE HUMIDITY DOWN TO THE LOWER TEENS TO SINGLE DIGITS!
WINDS ARE NOT AS STRONG AS YESTERDAY, BUT BREEZY WEST TO NORTHWEST
WINDS ARE CONTINUING TO PRODUCE WIDESPREAD CRITICAL FIRE WEATHER
CONDITIONS. WE DO EXPECT TO FIND SOME RELIEF THIS EVENING, AS A COLD
FRONT APPROACHES THE AREA. WHILE THE COOLER AIR WILL LAG SOMEWHAT
BEHIND THE WIND SHIFT, EXPECT THE BOUNDARY TO PUSH INTO THE CHADRON
AREA FIRST AROUND 6PM THIS EVENING, THEN SLOWLY MOVE SOUTHWESTWARD
OVERNIGHT INTO SATURDAY MORNING. NORTHEAST WINDS MAY BE GUSTY AT
TIMES OVERNIGHT OVER THE HIGH PLAINS. THIS FRONT WILL BE LARGELY
DRY, AS THE UPPER LEVEL SHORTWAVE LOOKS TO REMAIN JUST TO OUR NORTH.
HOWEVER, FORCING MAY CREEP AS FAR SOUTH AS THE US-20 CORRIDOR LATE
TONIGHT THROUGH EARLY SATURDAY AFTERNOON. POPS ARE ONLY AROUND 10 TO
25% OR SO AT THIS TIME, AND WIDESPREAD RAINFALL IS UNLIKELY, BUT
WORTH A MENTION IN THE FORECAST. TEMPERATURES WILL BE CONSIDERABLY
COOLER ON SATURDAY. WITH MORE CLOUD COVER FURTHER NORTH, THE US-20
CORRIDOR WILL STRUGGLE TO GET MUCH ABOVE 60 DEGREES, WHEREAS MORE
SUNSHINE FURTHER SOUTH WILL PUSH TEMPERATURES IN THE THE UPPER
60S TO LOW 70S.
THE SURFACE COLD FRONT WILL STALL SOMEWHERE ACROSS CARBON AND ALBANY
COUNTIES SATURDAY. THIS WILL MAKE FOR A HIGHLY UNCERTAIN WIND
FORECAST (PARTICULARLY IN THE WIND DIRECTION) ALONG THE I-80
CORRIDOR WITH GUSTY WESTERLY WINDS ANTICIPATED SOUTH OF THE
BOUNDARY, AND NORTH TO NORTHEAST WINDS TO THE NORTH. REGARDLESS OF
WHERE IT STALLS, EXPECT THE BOUNDARY TO SHIFT SOUTH SATURDAY EVENING
AS THE CORE OF THE SURFACE HIGH PUSHES UP AGAINST THE HIGHER
TERRAIN. A FAIRLY STRONG REVERSE PRESSURE GRADIENT WILL SETUP,
LEADING TO STRONG, GUSTY NORTHEAST WINDS IN CARBON COUNTY, AND GUSTY
SOUTHEAST WINDS AROUND THE LARAMIE AREA. IN ADDITION, HIGHER
HUMIDITY AND COOLER TEMPERATURES WILL PUSH A DECK OF LOW CLOUDS IN
AGAINST THE HIGHER TERRAIN. EAST SLOPES CAN EXPECT TO SEE SOME FOG,
INCLUDING THE I-80 SUMMIT AREA. ANOTHER WEAK SHORTWAVE ALOFT
WILL PASS OVER THE AREA SUNDAY. WHILE INSTABILITY LOOKS
EXTREMELY LIMITED, SYNOPTIC FORCING AND UPSLOPE FLOW MAY ALLOW
FOR THE DEVELOPMENT OF A FEW LIGHT SHOWERS ACROSS THE I-80
CORRIDOR, PARTICULARLY CLOSER TO THE LARAMIE RANGE. LOW-END POPS
IN THE 15 TO 30% RANGE WERE MAINTAINED WITH THIS UPDATE. WHILE
APPRECIABLE RAINFALL IS UNLIKELY, WE MAY SEE SOME LIGHT SHOWERS
ACROSS THE AREA IN THE MORNING, POSSIBLY WITH A FEW RUMBLES OF
THUNDER IN THE AFTERNOON HOURS. SUNDAY WILL BE ANOTHER COOL DAY.
OUR NORTHERN ZONES WILL BE A TOUCH WARMER THAN SATURDAY AS
CLEARING SKIES PUSH SOUTHWARD, BUT THE I-80 CORRIDOR WILL SEE
THE COOLEST DAY OF PERIOD, WITH HIGHS AROUND 10F BELOW SEASONAL
AVERAGES.
LONG TERM /MONDAY THROUGH FRIDAY/
ISSUED AT 300 PM MDT FRI JUN 12 2026
MONDAY MORNING, ANOTHER WEAK SHORTWAVE LOOKS TO PUSH THROUGH
THE INTERMOUNTAIN WEST AHEAD OF THE RIDGE PUSHING EASTWARD OFF
THE WEST COAST. HOWEVER, AS THIS RIDGE PUSHES EASTWARD, THE
RIDGE BEGINS TO FLATTEN DUE TO ANOTHER LOW PRESSURE SYSTEM
PUSHES INTO BRITISH COLUMBIA AND TRAVELS ALONG THE CANADIAN
PROVIDENCES UNTIL DROPPING INTO THE NORTHERN PLAINS AROUND
WEDNESDAY EVENING. THIS WILL CHANGE THE FLOW DIRECTION FROM
NORTHWEST ON MONDAY AND TRANSITION TO A WESTERLY DOWNSLOPE BY
TUESDAY EVENING. THIS CHANGE OF FLOW WILL RESULT IN SURFACE
TEMPERATURES INCREASING FROM THE 70'S ON MONDAY TO THE 80'S AND
90'S ON TUESDAY THROUGH WEDNESDAY. WINDS WILL BE RATHER GUSTY AS
WELL WHILE IN THE DOWNSLOPING FLOW TO DEVELOP ANOTHER FEW DAYS
OF POSSIBLE RED FLAG CONDITIONS.
AVIATION /06Z TAFS THROUGH 06Z SUNDAY/
ISSUED AT 1101 PM MDT FRI JUN 12 2026
VFR CONDITIONS WILL CONTINUE FOR THE DURATION OF THIS TAF PERIOD
ACROSS ALL TERMINALS, WITH WINDS BEING THE PRIMARY THREAT. AFTER
SOMEWHAT A CALM NIGHT, EXPECT WINDS TO RAMP UP BY 16Z WITH NORTH TO
NORTHEASTERLY GUSTS IN THE 20 TO 30 KNOT RANGE FOR ALL TERMINALS.
CLOUDS WILL RETURN NEAR 00Z SUNDAY, WITH CLOUD LAYERS AND/OR CIGS
DROPPING TO AROUND 10K FEET OR JUST BELOW.
CYS WATCHES/WARNINGS/ADVISORIES
WY...NONE.
NE...NONE.
SHORT TERM...MN
LONG TERM...MM
AVIATION...RZ
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