436
FXUS65 KRIW 140345
AFDRIW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
945 PM MDT SAT JUN 13 2026
KEY MESSAGES
- A COLD FRONT ACCOMPANIED BY GUSTY NORTHEAST WIND 20 TO 35 MPH
PUSHES THROUGH ROCK SPRINGS AND GREEN RIVER LATE SATURDAY
AFTERNOON, REACHING SOUTHERN LINCOLN COUNTY BY MIDNIGHT.
- CLOUD COVER CLEARS EAST OF THE CONTINENTAL DIVIDE DURING THE
MIDDAY HOURS SUNDAY, ALLOWING FOR DAYTIME HIGH TEMPERATURES
TO REBOUND 5 TO 10 DEGREES. AREAS WEST OF THE DIVIDE SEE
LITTLE CLOUD COVER AND SEASONAL TEMPERATURES SUNDAY.
- TEMPERATURES REBOUND TO SEASONAL NORMALS ACROSS THE ENTIRE
REGION MONDAY BEFORE WARMING SEVERAL MORE DEGREES TUESDAY.
- LIMITED TO NO RAIN CHANCES ALONG WITH THE WARM TEMPERATURES
AND INCREASING WEST WIND LEADS TO ELEVATED TO CRITICAL FIRE
CONDITIONS MUCH OF THE WEEK. TUESDAY LOOKS TO BE THE MOST
CRITICAL AS WESTERLY WIND BLOWS 20 TO 35 MPH.
UPDATE
ISSUED AT 937 AM MDT SAT JUN 13 2026
CLOUDS HAVE FULLY MOVED IN EAST OF THE DIVIDE, WHILE A CLEAR SKY IS
PRESENT WEST OF THE DIVIDE - VERY MUCH A TALE OF TWO DIVIDES TODAY.
HAVE LOWERED HIGHS A TOUCH EAST OF THE DIVIDE TODAY AS HIGH
TEMPERATURES WILL LIKELY STRUGGLE TO REACH THE MID-60S.
PRECIPITATION LINGERS LONGEST AROUND JOHNSON COUNTY, ENDING AROUND
SUNSET, THOUGH MOST FALLS BEFORE NOON. A FEW SHOWERS COULD ALSO
CONTINUE OVER THE ABSAROKA MOUNTAINS INTO TONIGHT. OTHERWISE, THE
FORECAST REMAINS ON TRACK FOR INCREASING TEMPERATURES THIS WEEK,
BACK INTO THE 80S AND 90S TUESDAY. WIDESPREAD ELEVATED TO CRITICAL
FIRE WEATHER IS POSSIBLE TUESDAY AS WINDS INCREASE.
DISCUSSION
ISSUED AT 147 AM MDT SAT JUN 13 2026
THE COLD FRONT REACHED THE DIVIDE EARLY THIS MORNING AND WILL CROSS
THE DIVIDE AFTER SUNRISE AS IT SLOWLY CONTINUES SOUTHWARD TODAY. AN
AREA OF SHOWERS CONTINUES JUST NORTH OF THE STATE LINE OVER SOUTHERN
MT. THESE SHOWERS WILL REACH THE BIGHORN BASIN AND NORTHERN PORTIONS
OF JOHNSON COUNTY BY THE PREDAWN HOURS. MOST OF THE PRECIPITATION
WILL OCCUR IN JOHNSON COUNTY AND THE BIGHORNS, WHERE MODEL TRENDS
HAVE INCREASED AMOUNTS CLOSE 0.50" NEAR BUFFALO AND POWDER RIVER
PASS BETWEEN 12Z AND 18Z (6AM AND 12PM). THIS WOULD RESULT IN
SNOWFALL AMOUNTS OF 5-6" ABOVE 9000FT. THERE IS CURRENTLY NO
LIGHTNING OCCURRING IN THESE SHOWERS AND NONE ARE EXPECTED THROUGH
THE REST OF THE MORNING, AS CONDITIONS ARE RELATIVELY STABLE WITH
TEMPERATURES IN THE 40S AND LOWER 50S. THESE SHOWERS WILL DWINDLE BY
18Z, WITH A 30 TO 60% CHANCE CONTINUING OVER THE ABSAROKAS AND
BIGHORNS THROUGH THE REST OF THE DAY. AN ISOLATED LIGHTNING STRIKE
COULD OCCUR OVER THESE AREAS IN THE AFTERNOON, BUT CONFIDENCE IS
LOW. THE REST OF THE FORECAST AREA WILL BE DRY AND COOL, WITH
TEMPERATURES IN THE 50S TO LOWER 60S EAST OF THE DIVIDE AND IN THE
60S AND 70S WEST OF THE DIVIDE. THE PROGRESSION OF THE COLD FRONT
OVER SOUTHERN PORTIONS WILL BE SLOWED BY NORTHWEST WINDS OVER
SOUTHWESTERN PORTIONS OF THE STATE. THE FRONT WILL FINALLY REACH THE
GREEN RIVER BASIN AFTER SUNSET, AS THE NORTHWEST WINDS WEAKEN.
EASTERLY WIND GUSTS OF 25 TO 45 MPH WILL OCCUR ACROSS SOUTHERN
PORTIONS OF THE CWA BEHIND THE FRONT THROUGH THE NIGHT AND INTO
SUNDAY MORNING.
SEASONAL TEMPERATURES WILL BE IN PLACE ACROSS THE CWA SUNDAY WITH
HIGHS IN THE UPPER 60S INTO THE 70S. CONDITIONS WILL BE DRY, EXCEPT
FOR VERY ISOLATED SHOWERS POSSIBLE OVER CENTRAL PORTIONS THROUGHOUT
THE DAY. WINDS WILL BE LIGHT AS WELL, WITH GUSTS OF 20 TO 25 MPH
OCCURRING OVER THE SOUTHERN HALF OF SWEETWATER COUNTY.
A WARMING TREND WILL BEGIN MONDAY, WITH A NORTHWEST FLOW PATTERN
ALOFT IN PLACE. HEIGHTS WILL RISE TUESDAY WITHIN THIS PATTERN,
LEADING TO HIGH TEMPERATURES IN THE UPPER 80S TO LOWER 90S IN THE
WIND RIVER AND BIGHORN BASINS AND PORTIONS OF NATRONA COUNTY.
TEMPERATURES WILL BE SLIGHTLY COOLER WEDNESDAY, AS A COLD FRONT
CLIPS NORTHERN PORTIONS OF THE STATE. THIS LOOKS TO BE THE BEST
CHANCES FOR ANY PRECIPITATION NEXT WEEK AS WELL, AS MUCH OF THE WEEK
LOOKS TO STAY DRY. FIRE WEATHER CONDITIONS WILL BE ELEVATED TO
CRITICAL THROUGH THE WEEK AS WELL, WITH TUESDAY LOOKING TO BE THE
MOST CRITICAL.
AVIATION /06Z TAFS THROUGH 06Z MONDAY/
ISSUED AT 945 PM MDT SAT JUN 13 2026
WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS TERMINALS
CONDITIONS REMAIN VFR THROUGH THE FORECAST PERIOD WITH LITTLE CLOUD
COVER EXPECTED. GUSTY NORTHEAST WIND 20 TO 35 MPH AT KRKS DECREASES
BETWEEN 09Z-12Z/SUNDAY LEAVING AN 8-14KT THROUGH EARLY SUNDAY
AFTERNOON. WEST TO NORTHWEST WIND 7-11KTS RETURNS TO ALL TERMINALS
BETWEEN 19Z-22Z/SUNDAY. ANOTHER SURGE OF NORTHEAST WIND 10-15KTS
PUSHES THROUGH KRKS AROUND 00Z/MONDAY.
EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL TERMINALS
BKN-OVC CEILINGS AT 040-070AGL PREVAIL OVERNIGHT AS FAVORABLE
NORTHERLY FLOW AND MID-LEVEL MOISTURE REMAIN ACROSS THE REGION. VFR
CONDITIONS SHOULD PREVAIL, ALTHOUGH THERE IS A 15 PERCENT CHANCE OF
MVFR IN THE UPSLOPE-FAVORED BASINS, MAINLY AT KLND. A SECONDARY
SHORTWAVE SWEEPS NORTHWEST-TO-SOUTHEAST THROUGH THE REGION
DURING THE MIDDAY HOURS SUNDAY ALLOWING FOR THE CLOUD COVER TO
SCATTER OUT. NORTH TO NORTHEAST SURFACE WIND 7-11KTS WILL BE
COMMON. MOUNTAIN TOPS FREQUENTLY OBSCURED THROUGH 18Z/SUNDAY.
PLEASE SEE THE AVIATION WEATHER CENTER AND/OR CWSU ZDV AND ZLC FOR
THE LATEST INFORMATION ON SMOKE, ICING, AND TURBULENCE FORECASTS.
RIW WATCHES/WARNINGS/ADVISORIES
NONE.
UPDATE...WITTMANN
DISCUSSION...LAVOIE
AVIATION...CNJ
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