922  
FXUS65 KRIW 280029  
AFDRIW  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE RIVERTON WY  
629 PM MDT MON JUL 27 2026  
   
KEY MESSAGES  
 
- SCATTERED SHOWERS AND A FEW EMBEDDED THUNDERSTORMS CONTINUE  
THROUGH MONDAY EVENING, WITH A FEW LIGHT SHOWERS LINGERING  
INTO THE EARLY MORNING HOURS TUESDAY.  
 
- MONSOON MOISTURE CONTINUES TO STREAM ACROSS THE REGION LEADING  
TO ANOTHER ROUND OF WIDELY SCATTERED SHOWERS AND THUNDERSTORMS  
TUESDAY AFTERNOON. THE BEST CHANCES WILL BE IN SWEETWATER  
COUNTY AND THE NORTHWEST MOUNTAINS.  
 
- THIS PATTERN REMAINS IN PLACE THROUGH THE WEEK, WITH ABOVE  
NORMAL TEMPERATURES AND SCATTERED SHOWERS AND THUNDERSTORMS  
DEVELOPING EACH AFTERNOON. WEDNESDAY REPRESENTS THE BEST  
CHANCE FOR MORE WIDESPREAD SHOWERS AND STORMS.  
 
 
   
UPDATE  
 
ISSUED AT 1007 AM MDT MON JUL 27 2026  
 
MORE CLOUDS TODAY AS MONSOONAL MOISTURE LINGERS OVER THE AREA  
WITH A WEAK WEATHER SYSTEM MOVING THROUGH. SHOWERS, AND THE  
OCCASIONAL STORM, HAS PERSISTED THROUGH THE MORNING.  
THUNDERSTORMS SHOULD BECOME MORE COMMON BY EARLY AFTERNOON AS  
THE SHORTWAVE MOVES THROUGH IN CONJUNCTION WITH PEAK DAYTIME  
HEATING. GUSTS TO 50 MPH ARE POSSIBLE WITH THESE STORMS.  
INTERESTINGLY, THE HRRR MODEL HAS A LONG LINE OF GUSTY WINDS 50  
TO 55 MPH ACCOSTED WITH THE MAIN PUSH OF SHOWERS AND STORMS FROM  
WESTERN WY STARTING ABOUT 2PM, MOVING EAST THROUGH THE AREA  
THROUGH ABOUT 9PM. WILL SEE IF THIS TREND HOLDS FOR EACH HOUR'S  
UPDATE. OTHERWISE, HAVE KEPT TEMPERATURES TODAY LESS THAN  
YESTERDAY GIVEN THE EXPECTED CLOUD COVER. INCREASING SMOKE WILL  
ALSO OCCUR OVER THE AREA, MAINLY NORTHERN WY TONIGHT INTO  
TOMORROW WITH THE FIRES IN THE WESTERN US, AS WELL AS A PLUME OF  
SMOKE COMING FROM THE SOUTHWEST ASSOCIATED WITH THE NEVADA  
FIRES.  
 
 
   
DISCUSSION  
 
ISSUED AT 231 AM MDT MON JUL 27 2026  
 
THE DOMINANT WESTERN RIDGING PATTERN HOLDS FIRM AGAIN TODAY,  
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  
THUNDERSTORM, 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 /00Z TAFS THROUGH 00Z WEDNESDAY/  
 
ISSUED AT 455 PM MDT MON JUL 27 2026  
 
VFR CONDITIONS ARE EXPECTED OVER THE NEXT 24 HOURS. SCATTERED  
SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE THIS EVENING UNTIL  
SHORTLY AFTER SUNSET, ROUGHLY UNTIL 28/0300Z. BRIEF HEAVY RAIN  
AND ERRATIC OUTFLOW WINDS GUSTING 30 TO 40 KT WILL BE THE  
PRIMARY THREATS WITH ANY STORM THAT DOES PASS NEAR TAF SITES.  
ISOLATED RAIN SHOWERS CONTINUE OVERNIGHT, ESPECIALLY ACROSS  
SOUTHERN WYOMING, WHERE A WEAK WEATHER SYSTEM WILL BE PASSING  
THROUGH THE BROADER ATMOSPHERIC FLOW. ANOTHER ROUND OF ISOLATED  
SHOWERS AND STORMS FORM TUESDAY AFTERNOON, MAINLY WEST OF THE  
CONTINENTAL DIVIDE.  
 
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  
 
AIR QUALITY ALERT UNTIL 1 PM MDT TUESDAY FOR WYZ010.  
 
 
 
 
 
UPDATE...WITTMANN  
DISCUSSION...STRAUB  
AVIATION...VANDENBOOGART/LAVOIE  
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