126  
FXUS65 KRIW 271106  
AFDRIW  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE RIVERTON WY  
506 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 /12Z TAFS THROUGH 12Z TUESDAY/  
 
ISSUED AT 503 AM MDT MON JUL 27 2026  
 
SHOWERS AND A FEW THUNDERSTORMS ALREADY STARTING TO BUILD UP  
ACROSS FAR NW WY THIS MORNING, WHICH SHOULD MOVE THROUGH QUICKLY  
IN THE NEXT COUPLE HOURS. REDEVELOPMENT IS LIKELY ACROSS MOST OF  
WESTERN WY BY 18Z, WITH IMPROVING CONFIDENCE FOR MORE NUMEROUS  
THUNDERSTORMS DURING THE AFTERNOON. HAVE UPDATED A FEW TAFS TO  
SWITCH TO TEMPO GROUPINGS FOR BRIEF LOWER VIS AND THUNDERSTORMS  
INTO THIS EVENING. MOST THUNDERSTORM ACTIVITY SHOULD BE  
DISSIPATING QUICKLY BY 00Z, BUT A FEW SHOWERS MAY CONTINUE  
THROUGH 06Z, MAINLY ACROSS NORTHERN WY. SCT TO BKN MIDLEVEL DECK  
EXPECTED TO CONTINUE THROUGH MOST OF THE OVERNIGHT HOURS  
TONIGHT.  
 
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...STRAUB  
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