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FXUS65 KCYS 170517
AFDCYS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
1117 PM MDT THU JUL 16 2026
KEY MESSAGES
- HOT, DRY, AND BREEZY CONDITIONS CONTINUE THROUGH SUNDAY BEFORE
A MUCH AWAITED COLD FRONT ARRIVES FOR THE START OF THE WEEK.
- SUNDAY LOOKS TO BE THE LAST 100+ DAY FOR THE UPCOMING WEEK OR
SO, WITH REDUCED FIRE CONCERNS ALSO ARRIVING WITH COOLER
WEATHER.
- MONSOONAL MOISTURE WILL ATTEMPT TO RETURN AS EARLY AS MONDAY,
LEADING TO INCREASED PRECIPITATION CHANCES THROUGH MUCH OF
NEXT WEEK.
SHORT TERM /THROUGH FRIDAY NIGHT/
ISSUED AT 120 PM MDT THU JUL 16 2026
TODAY AND TOMORROW SHOULD LOOK RELATIVELY SIMILAR AS UPPER LEVEL
RIDGING REMAINS CENTERED OVER THE REGION, WITH A SURFACE FRONTAL
BOUNDARY STALLED OUT ALONG OR JUST WEST OF OUR CWA. FLOW
POSITIONING WILL ALLOW MONSOONAL MOISTURE TO LIFT UP AND INTO
WESTERN WYOMING, BUT UNTIL LATER INTO THE WEEKEND, IT'S UNLIKELY
TO MAKE MUCH OF AN IMPACT FOR OUR AREA. THAT BEING SAID,
UPSLOPE FLOW AND SOME AT LEAST MEAGER PWAT VALUES AROUND
0.5-0.75" MAY FUEL SOME VERY ISOLATED SHOWER OR THUNDERSTORM
CHANCES AS EVIDENCED BY HIGH RESOLUTION GUIDANCE PRODUCING A FEW
ECHOES FOR OUR ZONES WEST OF THE LARAMIE RANGE, BUT WITH WEAK
FLOW ALOFT THIS ACTIVITY WILL BE FAIRLY STATIONARY, AND COMBINED
WITH INVERTED V SOUNDING PROFILES, MUCH OF THIS WILL BE VIRGA
THAT STRUGGLES TO MAKE IT TO THE SURFACE AND LIKELY PRODUCES DRY
LIGHTNING AND BREEZY WINDS. STILL, CAN'T RULE OUT AT LEAST AN
ISOLATED CELL ACTUALLY BRINGING RAIN TO THE GROUND, BUT DON'T
EXPECT MUCH OUT OF THIS ACTIVITY TODAY AND TOMORROW. OTHERWISE,
OUR CYCLE OF DIURNAL WINDS CONTINUES, WITH BREEZY CONDITIONS
DURING THE AFTERNOON AND RELAXING DURING THE EVENING AND NIGHT.
RELATIVE HUMIDITY VALUES REMAIN IN THE 15-20% RANGE, KEEPING OUR
FIRE WEATHER THREAT ELEVATED BUT NOT CRITICAL. TEMPERATURES
EACH DAY RANGE IN THE UPPER 80'S TO UPPER 90'S WITH A SITE OR
TWO IN WESTERN WYOMING AND/OR THE NEBRASKA PANHANDLE POTENTIALLY
REACHING TRIPLE DIGITS, HOT BUT NOT QUITE WARM ENOUGH TO
VALIDATE A HEAT ADVISORY YET (THOUGH THIS MAY CHANGE MOVING INTO
THE WEEKEND).
LONG TERM /SATURDAY THROUGH THURSDAY/
ISSUED AT 120 PM MDT THU JUL 16 2026
SATURDAY...WITH THE RIDGE ALOFT REMAINING PARKED OVER WYOMING, AND
WARM MID LEVEL TEMPERATURES PRODUCING ENOUGH CIN, CONVECTIVE
INHIBITION, THIS WILL LIMIT AREAL COVERAGE TO ISOLATED TO WIDELY
SCATTERED SHOWERS AND THUNDERSTORMS OVER OUR SNOWY AND SIERRA MADRE
RANGES IN THE AFTERNOON, AND OVER MUCH OF CARBON COUNTY INCLUDING
RAWLINS IN THE EVENING...OTHERWISE DRY.
SUNDAY...GFS PROGS THE RIDGE ALOFT OVER THE NORTHERN ROCKIES TO BE
FLATTENED SOMEWHAT WITH ZONAL FLOW DEVELOPING OVER MONTANA AND
NORTHERN WYOMING. A WEAK PERTURBATION, OR SHORTWAVE TROUGH ALOFT,
WILL MOVE ACROSS OUR COUNTIES IN THE AFTERNOON AND EVENING, WITH
MONSOONAL MOISTURE ADVECTING INTO OUR WESTERN COUNTIES WEST OF I-25,
WHERE WE ANTICIPATE SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP
IN THE AFTERNOON WEST OF I-25, WITH THE GREATEST AREAL COVERAGE OVER
THE SNOWY, SIERRA MADRE AND NORTHERN LARAMIE RANGES. SO, MORE
BENEFICIAL RAIN WILL OCCUR. MONSOONAL MOISTURE IS PROGGED TO ADVECT
FURTHER EASTWARD IN THE EVENING, SPAWNING ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS FOR OUR COUNTIES EAST OF I-25, WITH LESSER
COVERAGE OVER THE NEBRASKA PANHANDLE.
MONDAY...MONSOONAL MOISTURE AT LOW AND MID LEVELS INCREASES FURTHER,
AIDING IN ANOTHER INCREASE IN LATE DAY SHOWER AND THUNDERSTORM
COVERAGE, AND BENEFICIAL RAINS, WITH COVERAGE INCREASING TO
SCATTERED AND LIKELY, 40 TO 80 PERCENT POPS, WITH THE GREATEST
COVERAGE OVER AND NEAR OUR MOUNTAIN ZONES.
TUESDAY-THURSDAY...THE ZONAL FLOW ALOFT CONTINUES WITH ABUNDANT
MONSOONAL MOISTURE REMAINING OVER OUR CWA, COUNTY WARNING AREA,
HELPING TO PRODUCE SCATTERED TO NUMEROUS SHOWERS AND SCATTERED
THUNDERSTORMS IN THE AFTERNOONS AND EVENINGS WITH MORE BENEFICIAL
RAINFALL, AGAIN WITH THE HIGHEST AREAL COVERAGE OVER OUR SNOWY,
SIERRA MADRE AND LARAMIE RANGES.
AVIATION /06Z TAFS THROUGH 06Z SATURDAY/
ISSUED AT 1111 PM MDT THU JUL 16 2026
A WEAK LOW LEVEL JET IS BRINGING IN SLIGHTLY GUSTIER SOUTH
WINDS TO 25 KNOTS TO KSNY AND KCDR. ELSEWHERE WINDS ARE
GENERALLY CALM AND VARIABLE. TOMORROW AFTERNOON DIURNAL WINDS
KICK BACK UP IN THE AFTERNOON WITH THE DEVELOPMENT OF CUMULUS
CLOUDS AT 9 KFT. A FEW SHOWERS AND STORMS MAY BE POSSIBLE AT
KCDR AND KRWL. PROBABILITIES ARE TOO LOW TO INTRODUCE INTO TAFS,
BUT VARIABLE GUSTS TO ABOUT 35 KNOTS CAN BE EXPECTED IF ANY DO
FORM. OTHERWISE, VFR CONDITIONS ARE EXPECTED AT ALL TERMINALS.
CYS WATCHES/WARNINGS/ADVISORIES
WY...NONE.
NE...NONE.
SHORT TERM...CG
LONG TERM...RUBIN
AVIATION...RV
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