074  
FXUS65 KRIW 021115  
AFDRIW  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE RIVERTON WY  
515 AM MDT FRI MAY 2 2025  
   
KEY MESSAGES
 
 
- WARM AND DRY CONDITIONS TODAY THROUGH SATURDAY, WITH TEMPERATURES  
PEAKING 15 TO 20 DEGREES ABOVE NORMAL.  
 
- A SYSTEM WILL BEGIN TO PUSH INTO THE AREA SUNDAY, RETURNING  
RAIN SHOWERS TO WESTERN WYOMING SUNDAY AFTERNOON.  
 
- WIDESPREAD RAIN AND MOUNTAIN SNOW IS EXPECTED MONDAY AND  
TUESDAY, ESPECIALLY ACROSS CENTRAL AND SOUTHERN WYOMING.  
 

 
   
DISCUSSION
 
 
ISSUED AT 437 AM MDT FRI MAY 2 2025  
 
A STRENGTHENING RIDGE WILL BE THE DOMINANT WEATHER FEATURE FOR THE  
NEXT COUPLE OF DAYS AS IT BUILDS IN FROM THE WEST. MOSTLY CLEAR  
SKIES ARE EXPECTED TODAY, WITH TEMPERATURES PEAKING ABOUT 5 DEGREES  
ABOVE NORMAL FOR MOST LOCATIONS. WIND WILL REMAIN FAIRLY CALM,  
MAKING FOR A PLEASANT WEATHER DAY ACROSS THE AREA. THIS TREND  
CONTINUES ON SATURDAY AS THE RIDGE REACHES ITS MAXIMUM EXTENT OVER  
WYOMING; 700MB TEMPERATURES WILL RISE TO NEAR 10C, HELPING HIGHS  
PEAK 15 TO 20 DEGREES ABOVE NORMAL. HUMIDITY WILL DROP INTO THE  
TEENS BOTH TODAY AND SATURDAY ACROSS LOWER ELEVATIONS, THOUGH  
RELATIVELY LIGHT WIND SHOULD HELP TO MITIGATE FIRE WEATHER CONCERNS  
DURING THIS PERIOD.  
 
BY SUNDAY THE RIDGE WILL BEGIN TO BREAK DOWN AS A LONGWAVE TROUGH  
MOVES ONTO THE WEST COAST AND AN ASSOCIATED 500MB LOW DEEPENS ACROSS  
SOUTHERN CALIFORNIA. THIS WILL RETURN PRECIPITATION CHANCES WEST OF  
THE CONTINENTAL DIVIDE, THOUGH THE MAJORITY OF THE AREA IS EXPECTED  
TO SEE ANOTHER WARM AND DRY DAY. IT WILL BE BREEZIER AHEAD OF THE  
APPROACHING SYSTEM, WHICH MAY LEAD TO AN INCREASING FIRE WEATHER  
CONCERN FOR SOUTHERN AND CENTRAL WYOMING.  
 
THE LOW WILL DRIFT NORTHEASTERLY ON MONDAY, SENDING A SURGE OF  
MOISTURE TO THE ROCKIES. THIS WILL SPREAD RAIN AND MOUNTAIN SNOW  
WIDELY ACROSS THE AREA THROUGH TUESDAY. THERE IS STILL SOME  
INCONSISTENCY ON WHERE THE LOW WILL SET UP AS IT APPROACHES WYOMING  
WHICH WILL HAVE AN IMPACT ON HOW MUCH MOISTURE IS REALIZED.  
REGARDLESS, THE GENERAL TRACK OF THE LOW TO OUR SOUTH SHOULD LEAD TO  
A RESPECTABLE PRECIPITATION EVENT FOR MUCH OF THE AREA, ESPECIALLY  
ACROSS CENTRAL WYOMING WHERE AN UPSLOPING, NORTHEASTERLY FLOW  
DEVELOPS. CURRENTLY, FORECAST PRECIPITABLE WATER VALUES ARE OVER  
0.60" FOR MUCH OF THE AREA. THIS IS NEAR THE CLIMATOLOGICAL MAXIMUM  
FOR THIS TIME OF YEAR AT KRIW (SPC SOUNDING CLIMATOLOGY). FOR  
CONTEXT, THIS VALUE IS ONLY RIGHT AROUND THE MEAN DAILY PRECIPITABLE  
WATER VALUES SEEN IN JULY. WITH TEMPERATURES EXPECTED TO REMAIN ON  
THE WARMER SIDE, SNOW WILL BE LIMITED TO THE MOUNTAINS, WITH THE  
MOST ALONG THE EASTERN SLOPES OF THE WIND RIVER RANGE. GIVEN THE  
WARM WEEKEND FOLLOWED BY A DECENT RAIN EVENT, RIVER FLOOD POTENTIAL  
MAY BE ELEVATED EARLY NEXT WEEK.  
 
FURTHER AHEAD, ENSEMBLE CLUSTER GUIDANCE INDICATES A QUICK RETURN TO  
RISING 500MB HEIGHTS BY WEDNESDAY. THIS FAVORS WARMER AND DRIER  
CONDITIONS THROUGH THE END OF NEXT WEEK.  
 

 
   
AVIATION /12Z TAFS THROUGH 12Z SATURDAY/
 
 
ISSUED AT 515 AM MDT FRI MAY 2 2025  
 
DRY AND VFR FLIGHT CONDITIONS EXPECTED THIS TAF PERIOD AS HIGH  
PRESSURE DOMINATES THE REGION. WINDS WILL LARGELY REMAIN LIGHT  
(10KTS OR LESS) AT ALL TERMINALS.  
 
PLEASE SEE THE AVIATION WEATHER CENTER AND/OR CWSU ZDV AND ZLC FOR  
THE LATEST INFORMATION ON ICING AND TURBULENCE FORECASTS.  
 

 
   
RIW WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  
 

 
 

 
 
DISCUSSION...MYERS  
AVIATION...GERHARDT  
 
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