512  
FXUS65 KRIW 270904  
AFDRIW  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE RIVERTON WY  
304 AM MDT MON JUL 27 2026  
   
KEY MESSAGES  
 
- INCREASED CLOUD COVER WILL KEEP TEMPERATURES DOWN A FEW  
DEGREES FROM YESTERDAY'S RECORD HIGH TEMPERATURES. AFTERNOON  
HIGHS WILL STILL REACH THE 90S ACROSS THE STATE.  
 
- SCATTERED SHOWERS AND THUNDERSTORMS WILL AGAIN DEVELOP EARLY  
THIS AFTERNOON AND MOVE TO THE NORTHEAST DURING THE DAY.  
MONSOON MOISTURE WILL BE ON THE INCREASE THIS MORNING, LEADING  
TO BETTER CHANCES FOR THUNDERSTORMS THAN PREVIOUS DAYS.  
 
- THIS PATTERN REMAINS IN PLACE THROUGH THE WEEK, WITH ABOVE  
NORMAL TEMPERATURES IN THE 90S AND THUNDERSTORMS DEVELOPING  
EACH AFTERNOON.  
 
 
   
DISCUSSION  
 
ISSUED AT 231 AM MDT MON JUL 27 2026  
 
THE DOMINANT WESTERN RIDGING PATTERN HOLDS FIRM AGAIN TODAY, THE  
THE H5 RIDGE STILL ANCHORED ON THE FOUR CORNERS REGION. THE  
SOUTHWEST TAP OF MONSOON MOISTURE CONTINUES TODAY, AND MOST  
MODELS ARE BRINGING AN INCREASE IN MOISTURE DURING THE NEXT 6 TO  
12 HOURS. WITH WARM TEMPERATURES STILL IN PLACE, DAYTIME SHOWERS  
AND THUNDERSTORMS WILL AGAIN DEVELOP LATE THIS MORNING AND  
CONTINUE INTO THE AFTERNOON, MOVING TO THE NORTHEAST. THE  
INCREASED MOISTURE AND SHORTWAVE ENERGY PASSING THROUGH TODAY  
WILL BRING A BETTER CHANCE FOR MEASURABLE RAINFALL FROM ANY  
THUNDERSTORMS, BUT THE GOOD FORWARD MOTION OF ANY STORMS WILL  
KEEP THE CHANCE FOR FLOODING LOW. CURRENT CLOUD COVER AND ANY  
COVER FROM THUNDERSTORMS TODAY WILL KEEP TEMPERATURES LOWER  
THAN SUNDAY. HIGHS WILL STILL BE ABOVE NORMAL, BUT WILL HOLD IN  
THE LOW TO MID 90S THROUGH THE AFTERNOON.  
 
TUESDAY WILL BE SIMILAR TO TODAY, WITH VERY WARM TEMPERATURES  
DURING THE DAY. AMPLE MOISTURE WILL TAP THIS HEAT FOR SCATTERED  
SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON. MIDLEVEL SUPPORT  
MAY BE MORE LIMITED, SO SHOWERS MIGHT END UP MORE ISOLATED.  
 
WEDNESDAY ANOTHER MORE VIGOROUS SHORTWAVE COMES AROUND THE RIDGE  
THROUGH WYOMING, WHICH IS EXPECTED TO BRING A MUCH BETTER CHANCE  
FOR SHOWERS AND THUNDERSTORMS. AFTER THIS FEATURE PASSES  
THROUGH, MODELS ARE SHIFTING THE RIDGE SLIGHTLY TO THE WEST  
THROUGH THE REST OF THE WEEK INTO THE UPCOMING WEEKEND. MODELS  
ARE NOTING A SIGNIFICANT DROP IN MOISTURE, AS THE MONSOON  
MOISTURE GETS CUT OFF. THIS WOULD LEAD TO MUCH DRIER AND WARMER  
PERIOD HEADING INTO THE WEEKEND.  
 
 
   
AVIATION /06Z TAFS THROUGH 06Z TUESDAY/  
 
ISSUED AT 1015 PM MDT SUN JUL 26 2026  
 
CHANCES FOR LIGHT, WEAK SHOWERS WILL CONTINUE OVER SOUTHERN  
PORTIONS OF THE FORECAST AREA TO START THE TAF PERIOD, AS A  
MOIST, SOUTHWEST FLOW BRINGS ANOTHER MOISTURE SURGE NORTHWARD  
THROUGH THE REST OF THE NIGHT. THESE SHOWERS WILL SPREAD  
NORTHWARD OVER THE WESTERN MOUNTAINS BETWEEN 10Z AND 13Z. GUSTY  
OUTFLOW WIND AROUND 35KT WILL BE POSSIBLE THROUGH THE REST OF  
THE MORNING WITH THESE SHOWERS. THIS MOISTURE THEN SERVES AS  
THE FUEL FOR ANOTHER ROUND OF DIURNAL CONVECTION BEGINNING  
AROUND MID- AFTERNOON MONDAY. MANY TERMINALS SEE WIND LESS THAN  
10KT, OUTSIDE OF CONVECTION, UNTIL LATE MONDAY AFTERNOON WHEN  
CONVECTIVE OUTFLOWS OCCUR.  
 
THE SHOWERS OVER THE WESTERN MOUNTAINS WILL SPREAD EAST INTO THE  
CENTRAL BASINS AND OTHER POINTS EAST OF THE DIVIDE LATE IN THE  
MORNING INTO EARLY AFTERNOON. ADDITIONAL THUNDERSTORMS LOOK TO  
DEVELOP OVER THE UPPER GREEN RIVER BASIN AND SOUTHERN PORTIONS  
AFTER 21Z AND MOVE TOWARD THE NORTHEAST INTO THE EVENING. WILL  
KEEP THE CURRENT PROB30 GROUPS THAT ARE ALREADY IN PLACE, AS  
WIDESPREAD CONVECTION IS STILL EXPECTED DURING THE AFTERNOON.  
THIS MAY CHANGE DEPENDING ON HOW THE MORNING SHOWERS IMPACT THE  
AFTERNOON CONVECTION.  
 
PLEASE SEE THE AVIATION WEATHER CENTER AND/OR CWSU ZLC AND ZDV FOR  
THE LATEST INFORMATION ON SMOKE, ICING, AND TURBULENCE  
FORECASTS.  
 
 
   
RIW WATCHES/WARNINGS/ADVISORIES  
 
NONE.  
 
 
 
 
 
DISCUSSION...STRAUB  
AVIATION...CNJ/LAVOIE  
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