555
FXUS65 KRIW 080443
AFDRIW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
943 PM MST SAT MAR 7 2026
KEY MESSAGES
- LIGHT SNOW OVER WESTERN WYOMING MOUNTAIN PEAKS OVERNIGHT. SNOW
SHOWERS MAY OCCASIONALLY DRIFT OVER THE VALLEYS, BUT NO
ACCUMULATION IS EXPECTED FOR VALLEYS.
- WEST-NORTHWEST WINDS REMAIN BREEZY OVERNIGHT NEAR CODY AND THE
UPPER WIND RIVER BASIN INCLUDING DUBOIS.
- SUNDAY WILL BE ANOTHER DAY FOR STRONG AND GUSTY WINDS IN THE
CODY FOOTHILLS AND THE EASTERN SLOPES OF THE ABSAROKA
MOUNTAINS. HIGH WIND WARNINGS ARE IN EFFECT FOR THESE AREAS.
- A WINDY WEEK AHEAD FOR WYOMING, WITH GUSTS OF 30 TO 45 MPH.
THE STRONGEST WINDS ARE CURRENTLY FORECAST TO OCCUR THURSDAY.
UPDATE
ISSUED AT 1143 AM MST SAT MAR 7 2026
FOR TODAY, NO REAL CHANGES TO THE FORECAST. THE MAIN STORY IS THE
WIND, WITH GUSTS 30 TO 40 MPH FROM ROCK SPRINGS TO CASPER, OVER THE
UPPER WIND RIVER BASIN, AND FOR THE HIGHER TERRAIN OF THE ABSAROKA,
WIND RIVER, AND BIGHORN MOUNTAINS. LOCALLY HIGHER GUSTS 40 TO 50 MPH
ARE POSSIBLE FOR WIND PRONE LOCATIONS. THOUGH WINDS DECREASE A BIT
TONIGHT, GUSTY WINDS CONTINUE OVERNIGHT FOR THESE LOCATIONS. AS
MENTIONED IN THE FULL DISCUSSION, WIND IS THE THEME FOR THE WEATHER
THIS COMING WEEK, WITH WIDESPREAD GUSTY WINDS 30 TO 60 MPH.
THE WATCHES HAVE BEEN UPGRADED TO HIGH WIND WARNINGS FOR SUNDAY
AFTERNOON AND EVENING OVER THE EASTERN ABSAROKAS AND THE CODY
FOOTHILLS. GUSTS TO 60 MPH ARE LIKELY (80%) HERE, WITH ISOLATED AND
SUDDEN GUSTS TO 70 MPH, ESPECIALLY NEAR CLARK (NORTH OF CODY).
DISCUSSION
ISSUED AT 153 AM MST SAT MAR 7 2026
DRY CONDITIONS AND CLEAR SKIES ARE CURRENTLY IN PLACE ACROSS THE CWA
EARLY THIS MORNING. SOME LOW CLOUDS (< 3000FT) CONTINUE ACROSS
PORTIONS OF SWEETWATER COUNTY AND OVER SOUTH PASS. THESE CLOUDS ARE
EXPECTED TO LAST THROUGH 15Z, BEFORE SCATTERING OUT. THERE IS A 50%
CHANCE FOR THESE CEILINGS TO DROP BELOW 1000FT BETWEEN 12Z AND
15Z OVER AREAS NORTH OF ROCK SPRINGS TOWARD FARSON.
NORTHWEST FLOW ALOFT WILL BE IN PLACE TODAY, AS A STRONG RIDGE OVER
THE EPAC BEGINS TO FOLD OVER THE PACNW. CLOUDS WILL INCREASE OVER
NORTHWESTERN PORTIONS BY SUNRISE THIS MORNING, LEADING TO INCREASED
CHANCES OF 30-60% FOR SNOW SHOWERS OVER THE FAR WESTERN MOUNTAINS.
SNOWFALL AMOUNTS WILL BE MEAGER FOR MOST OF THESE LOCATIONS (UP TO
AN INCH), BUT 2 TO 3 INCHES WILL FALL FROM THIS AFTERNOON AND
TONIGHT OVER THE PITCHSTONE PLATEAU AND THE TETONS. CONDITIONS WILL
REMAIN DRY ELSEWHERE ACROSS THE FORECAST AREA, WITH WEST WIND GUSTS
OF 25 TO 35 MPH RETURNING ACROSS SOUTHERN PORTIONS AND THE WIND
CORRIDOR (ROCK SPRINGS TO SOUTHERN JOHNSON COUNTY). SLIGHTLY HIGHER
WIND GUSTS UP TO 45 MPH WILL OCCUR NEAR CODY AND THE UPPER WIND
RIVER BASIN, WITH THE WINDS NEAR CODY LASTING THROUGH THE OVERNIGHT
HOURS TONIGHT. THE LATTER WINDS COULD REACH THE RIVERTON AREA LATE
IN THE AFTERNOON, BUT WITH SLIGHTLY LOWER GUSTS AROUND 35 MPH. THESE
WINDS WILL CONTINUE THROUGH THE EVENING AND BEGIN TO DECREASE AFTER
06Z. ABOVE NORMAL TEMPERATURES WILL RETURN EAST OF THE DIVIDE AS A
RESULT OF THESE WINDS.
THE MAIN WEATHER HAZARD FOR THE CWA IN THE NEXT 7 DAYS WILL BE WIND.
WINDY CONDITIONS WILL IMPACT MUCH OF THE CWA EACH DAY, WITH AREAS OF
STRONG TO HIGH WIND (WARNING-LEVEL CRITERIA OF 58+ MPH) OCCURRING
HERE AND THERE. THE MECHANISM BEHIND THESE WINDS WILL BE A STRONG
140+KT PFJ. THIS JET WILL BE THE REASON THE RIDGE IS FOLDING OVER
TODAY AND WILL FLATTEN BY SUNDAY FROM THE "WEIGHT" OF ALL THIS
ENERGY.
THE JET WILL MAKE ITS WAY OVER SOUTHERN BRITISH COLUMBIA AS THE
RIDGE FLATTENS. THE RIGHT FRONT QUADRANT OF THE JET WILL BE OVER
SOUTHERN MT BY 12Z SUNDAY, PUSHING SOUTHWARD OVER FAR NORTHERN
PORTIONS THROUGH THE DAY. THIS WILL RESULT IN A STRONG DOWNSLOPING
SIGNATURE DEVELOPING BETWEEN 09Z AND 12Z SUNDAY. THIS IS MARKED BY A
TIGHT 700MB TEMPERATURE GRADIENT ALONG THE EAST SLOPES OF THE
ABSAROKA AND WIND RIVER MOUNTAINS, RANGING FROM 5C TO MINUS 6C OVER
THE MOUNTAINS. 700MB WINDS ALSO INCREASE TO 50KT IN THIS AREA,
INDICATING THE POTENTIAL FOR STRONG GAP FLOW NEAR CLARK AND CHIEF
JOSEPH PASS. WILL ISSUE HIGH WIND WATCHES FOR THE ABSAROKAS AND CODY
FOOTHILLS AS A RESULT. OTHERWISE, SIMILAR CONDITIONS FROM TODAY WILL
RETURN SUNDAY WITH LIGHT SNOW CONTINUING OVER PORTIONS OF
YELLOWSTONE. GUSTY WEST TO NORTHWEST WINDS WILL RETURN TO MUCH OF
THE SAME AREAS, WITH GUSTS OF 25 TO 45 MPH BEING WIDESPREAD. THE
FOCUS FOR THE HIGHER WINDS WILL BE OVER THE WESTERN MOUNTAINS AND
EAST OF THE DIVIDE. THE EAST SLOPES OF THE WIND RIVER AND BIGHORN
MOUNTAINS WILL ALSO HAVE GUSTS OF 50 TO 60 MPH. ABOVE NORMAL
TEMPERATURES WILL ALSO RETURN AS A RESULT OF THESE WINDY CONDITIONS.
AREAS EAST OF THE DIVIDE WILL BE IN THE 60S, WITH A FEW LOCATIONS IN
EASTERN JOHNSON COUNTY APPROACHING 70F.
A MORE ZONAL FLOW PATTERN WILL BE IN PLACE MONDAY WITH THE PFJ
EXTENDING FROM THE PACNW TO THE GREAT LAKES. ALTHOUGH THE CORE
OF THE JET WILL BE NORTH OF THE COWBOY STATE, THE GRADIENT WILL
REMAIN TIGHT WITH WIDESPREAD 30 TO 50KT 700MB WINDS OVER MUCH OF
THE CWA. WEST TO NORTHWEST WINDS, WITH GUSTS OF 35 TO 45 MPH
LOOK TO BE WIDESPREAD OVER MUCH OF THE AREA AS A RESULT OF THESE
CONDITIONS. UPPER LEVEL CONVERGENCE AND STRONG DOWNWARD MOTION
WILL CONTINUE OVER THE EAST SLOPES OF THE ABSAROKA AND WIND
RIVER MOUNTAINS, LEADING TO WIND GUSTS OF 60 TO 70 MPH (SOME
MODELS ARE INDICATING LOCALLY HIGHER GUSTS APPROACHING 80 MPH).
LIGHT SNOW WILL BE POSSIBLE OVER NORTHWESTERN PORTIONS DUE TO
OROGRAPHIC FLOW AND LIMITED PACIFIC MOISTURE, BUT ACCUMULATIONS
LOOK TO BE MINOR AT THIS TIME. TEMPERATURES WILL CONTINUE TO BE
WELL ABOVE NORMAL FOR EARLY MARCH, AS THE WINDS KEEP THE
ATMOSPHERE WELL MIXED.
LIGHT SNOW WILL CONTINUE INTO MONDAY NIGHT AND TUESDAY, AS THE UPPER
LEVEL FLOW OVER NORTHWESTERN PORTIONS BECOMES MORE CYCLONIC AS A
COLD FRONT SLOWLY DROPS SOUTHWARD FROM MT. THE FRONT WILL SLOWLY
PROGRESS SOUTHWARD THROUGH THE DAY TUESDAY, REACHING THE WY/CO
BORDER BY 06Z WEDNESDAY. WINDS WILL ALSO DECREASE SUBSTANTIALLY
MONDAY NIGHT AS A RESULT OF THE FRONT. HOWEVER, THEY WILL INCREASE
AGAIN OVER CENTRAL AND SOUTHERN PORTIONS IN THE WAKE OF THE FRONT.
IN ADDITION TO THE FRONT'S SLOW PROGRESSION, NORTHERN PORTIONS WILL
HAVE THE BEST CHANCES FOR SNOW. TEMPERATURES WILL REMAIN NEAR
SEASONAL LEVELS AS A RESULT OF THE FRONT, WHILE CENTRAL AND SOUTHERN
PORTIONS REMAIN AT OR SLIGHTLY ABOVE NORMAL. MOST OF THE SNOW WILL
BE OVER THE NORTHERN MOUNTAINS AND EAST OF THE DIVIDE, WITH LITTLE
TO NO ACCUMULATION OCCURRING IN THE LOWER ELEVATION. THIS WILL DUE
TO THE WARMER CONDITIONS OVER THE NEXT 3 DAYS AND HIGHER MARCH SUN
ANGLE. INITIAL INDICATIONS SHOW 3 TO 6 INCHES OVER THE BIGHORNS,
WITH MOST OF THIS OCCURRING ON THE NORTHERN END AND 1 TO 3 INCHES
OVER NORTHERN JOHNSON COUNTY.
DRY CONDITIONS RETURN WEDNESDAY, AS A RIDGE REBUILDS OVER THE GREAT
BASIN AND THE STORM FROM TUESDAY STRENGTHENS OVER THE GREAT LAKES
AND MID-MISSISSIPPI VALLEY. BREEZY TO WINDY CONDITIONS LOOK TO
RETURN AS WELL, WITH ELEVATED FIRE WEATHER CONDITIONS ACROSS AREAS
EAST OF THE DIVIDE. THIS TREND OF WIDESPREAD WINDY CONDITIONS, AND
POSSIBLY HIGH WINDS IN MORE WIND PRONE LOCATIONS, LOOKS TO CONTINUE
THURSDAY AND FRIDAY AS THE PFJ BECOMES SOMEWHAT ZONAL (FROM THE
PACNW TO THE MIDWEST) AND FEEDS INTO THE TUESDAY/WEDNESDAY STORM
SYSTEM AS IT MOVES OVER THE NORTHEAST CONUS. THIS KEEPS THE GRADIENT
TIGHT OVER THE COWBOY STATE WITH A 160KT JET MAX OVER EASTERN
MT.
AVIATION /06Z TAFS THROUGH 06Z MONDAY/
ISSUED AT 940 PM MST SAT MAR 7 2026
VFR CONDITIONS PREVAIL FOR MOST LOCATIONS OVER THE NEXT 24
HOURS. JAC AND TIGHT WESTERN WYOMING VALLEYS WILL BE THE ONE
EXCEPTION, AS MOUNTAIN SNOW SHOWERS OVERNIGHT COULD DRIFT OVER
THE VALLEYS OCCASIONALLY CAUSING REDUCTIONS IN VISIBILITY AND
LOWER CEILINGS. MIDDLE ATMOSPHERE STRATUS DECKS CURRENTLY OVER
WESTERN WYOMING SHOULD THIN AROUND SUNRISE.
WINDS GUSTING 20 TO 30 KT CONTINUE FOR MUCH OF THE OVERNIGHT
HOURS AT COD, CPR, AND RIW. DURING THE AFTERNOON HOURS SUNDAY,
MOST LOCATIONS WILL SEE GUSTS IN THIS 20 TO 30 KT RANGE, WITH
WINDIER SPOTS SUCH AS COD AND CPR SEEING GUSTS TO 40 KT AT
TIMES. WINDS DECREASE AFTER SUNSET SUNDAY, BUT REMAIN BREEZY
INTO MONDAY.
RIW WATCHES/WARNINGS/ADVISORIES
HIGH WIND WARNING FROM NOON TO 11 PM MST SUNDAY FOR WYZ002-003.
UPDATE...WITTMANN
DISCUSSION...LAVOIE
AVIATION...VANDENBOOGART
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