834  
FXUS65 KRIW 211736  
AFDRIW  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE RIVERTON WY  
1036 AM MST FRI FEB 21 2025  
   
KEY MESSAGES  
 
- SEASONAL TEMPERATURES AND DRY TODAY.  
 
- CONTINUING TO WATCH FOR THE POSSIBILITY OF ICE JAMMING AND FLOODING  
SUNDAY THROUGH TUESDAY ACROSS THE BIGHORN BASIN AND JOHNSON  
COUNTY. THIS IS DUE TO WARMING TEMPERATURES.  
 
- SNOW CHANCES RETURN TO WESTERN WYOMING SUNDAY AS A WEAK  
WEATHER SYSTEM PASSES. LOWER ELEVATIONS MAY SEE RAIN OR  
RAIN/SNOW MIX.  
 
 
   
UPDATE  
 
ISSUED AT 755 AM MST FRI FEB 21 2025  
 
LOW AND MIDDLE LEVEL CLOUDS ARE STILL AROUND PORTIONS OF THE AREA  
THIS MORNING, BUT ARE ON A DECREASING TREND THE NEXT FEW HOURS AS  
THE SUN BURNS THEM AWAY. NO REAL CHANGE IN THE FORECAST FOR TODAY  
WITH THIS MORNING UPDATE. TEMPERATURES TODAY ARE ABOUT SEASONAL,  
WITH HIGHS IN THE 30S FOR MOST OF THE AREA. DRY CONDITIONS EXPECTED  
TODAY AS WELL.  
 
 
   
DISCUSSION  
 
ISSUED AT 1230 AM MST FRI FEB 21 2025  
 
IR CURRENTLY DEPICTS CLEARING SKIES ACROSS MUCH OF THE STATE AS  
UPPER LEVEL RIDGING BUILDS IN FROM THE WEST. SOME COOLER CLOUD  
TOPS ACROSS FAR SOUTHERN REACHES OF THE CWA ALONG THE COLORADO  
STATE LINE WITH SOME LIGHT LINGERING SNOW FLURRIES PUSHING OUT.  
THE MAIN FINGER OF THE PFJ CONTINUES TO STAY TO THE NORTHEAST  
DIVING INTO THE GREAT PLAINS KEEPING THE COLDER TEMPERATURES  
AWAY. THE WEAK DISTORTION OF THE JET DIVING SOUTH OF THE CWA  
HAS SUPPORTED THIS PREVIOUS DISTURBANCE THAT NOW WILL PUSH TO  
THE SOUTHEAST GIVING WAY TO TRANQUIL WEATHER CONDITIONS FOR  
FRIDAY AND INTO THE WEEKEND. INCREASING UPPER LEVEL CONVERGENCE  
WILL ALLOW FOR HIGHER PRESSURE AT THE SURFACE AND WARMING  
TEMPERATURES EVEN INTO EARLY NEXT WEEK. AS A RESULT, THE MAIN  
CONCERN WILL BE FOR ICE JAMMING AND FLOODING FOR AREA IN  
NORTHERN BIGHORN BASIN AND JOHNSON COUNTY DUE TO THE RECENT  
SNOWPACK IN LOWER ELEVATIONS. TEMPERATURES EAST OF THE DIVIDE  
WILL PUSH INTO THE 40S FRIDAY AND SATURDAY AND 50S TO NEAR 60  
SUNDAY THROUGH TUESDAY. WEST OF THE DIVIDE WILL REMAIN IN THE  
30S FOR MUCH OF THIS TIME AS THE NEXT DISTURBANCE WILL START TO  
AFFECT THESE AREAS COME SUNDAY THROUGH MID WEEK.  
 
THE MAIN PFJ DIPS FURTHER SOUTH ACROSS MONTANA TO NORTHERN  
REACHES OF WYOMING BY SUNDAY AFTERNOON GIVING WAY TO THE PACIFIC  
NORTHWEST MOISTURE ONCE AGAIN. THIS WILL INCREASE SNOW CHANCES  
WEST OF THE DIVIDE, MAINLY FOR THE WESTERN MOUNTAINS THROUGH MID  
WEEK. A MIX TO EVEN JUST LIQUID PRECIPITATION POSSIBLE FOR THE  
LOWER VALLEYS AS TEMPERATURES COULD REMAIN ABOVE THE FREEZING  
MARK FOR MUCH OF THIS PERIOD. TIME WILL TELL, BUT A FORWARD LOOK  
ON SNOW ACCUMULATIONS LOOK TO BE MODEST AT BEST TO POSSIBLE  
ADVISORY LEVEL CRITERIA FOR THE WESTERN MOUNTAINS TO INCLUDE THE  
MAIN PASSES AS PER USUAL WITH THE ZONAL WESTERLY FLOW. THE MAIN  
TROUGH LOOKS TO PASS THROUGH THE REST OF THE STATE TO THE EAST  
LATE TUESDAY AND INTO EARLY WEDNESDAY THAT WILL GIVE REALLY THE  
ONLY CHANCE FOR PRECIPITATION EAST OF THE DIVIDE IN THE LONG  
TERM PERIOD. WITH THE WARMER TEMPERATURES ABOVE FREEZING  
(ALTHOUGH COOLER TUESDAY AND WEDNESDAY) LIQUID RAIN THE LIKELY  
PRECIPITATION FOR THE LOWER ELEVATIONS AND LIKELY SNOW FOR THE  
BIGHORNS. OTHERWISE, RIDGING BUILDS BACK IN FOR THE REMAINDER OF  
THE WEEK AND INTO THE FOLLOWING WEEKEND WITH DECREASED  
DIVERGENCE ALOFT LOOKING TO BE A POSSIBLE OMEGA BLOCK TO END  
THE REST OF THE MONTH AND INTO MARCH. WINTER IS STILL NOT DONE,  
BUT IT IS IN ITS WANING HOURS IN THE LONGER TERM OUTLOOK.  
 
 
   
AVIATION /18Z TAFS THROUGH 18Z SATURDAY/  
 
ISSUED AT 1033 AM MST FRI FEB 21 2025  
 
LITTLE TO NO AVIATION CONCERNS WEATHERWISE DURING THE MEXT 24  
HOURS. CLOUDS CONTINUE TO MOVE AWAY FROM WY, WITH QUICKLY  
THINNING CLOUDS AT KRKS. REMAINING SITES REMAIN CLEAR INTO THE  
OVERNIGHT HOURS. A FEW CIRRUS WILL START TO SWEEP IN FROM THE  
NORTHWEST LATE TONIGHT INTO SATURDAY MORNING. A FEW AREAS COULD  
GET BREEZY THIS AFTERNOON, MAINLY AT KRKS, KCPR, AND KDUB, BUT  
GUSTS TODAY WILL REMAIN BELOW 20KTS. WINDIER SATURDAY WITH MORE  
FREQUENT GUSTS TO 40KTS AT KCPR.  
 
 
   
RIW WATCHES/WARNINGS/ADVISORIES  
 
NONE.  
 
 
 
 
 
UPDATE...WITTMANN  
DISCUSSION...LOWE  
AVIATION...STRAUB  
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