204  
ACUS01 KWNS 031951  
SWODY1  
SPC AC 031949  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0249 PM CDT FRI OCT 03 2025  
 
VALID 032000Z - 041200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE GREAT BASIN/INTERMOUNTAIN WEST...  
   
..SUMMARY
 
 
THUNDERSTORMS CAPABLE OF ISOLATED SEVERE WIND GUSTS AND SMALL HAIL  
WILL BE POSSIBLE FROM LATE THIS AFTERNOON INTO TONIGHT ACROSS PARTS  
OF THE GREAT BASIN AND INTERMOUNTAIN WEST.  
   
..20Z UPDATE
 
 
THE FORECAST REMAINS ON TRACK AND ONLY MINOR ADJUSTMENTS WERE MADE  
WITH THIS UPDATE. IN PARTICULAR, THE MRGL RISK WAS EXTENDED SLIGHTLY  
WESTWARD INTO FAR NORTHEASTERN NV, DRIVEN BY 5-PERCENT WIND  
PROBABILITIES. DESPITE LIMITED MOISTURE/BUOYANCY, STRENGTHENING  
LARGE-SCALE ASCENT IN THE LEFT-EXIT REGION OF A ROBUST MIDLEVEL JET  
AND STEEPENING DEEP-LAYER LAPSE RATES AMID STRONG LOW/MID-LEVEL FLOW  
COULD SUPPORT A COUPLE STRONG CONVECTIVELY ENHANCED WIND GUSTS. SEE  
THE PREVIOUS DISCUSSION BELOW FOR MORE DETAILS.  
 
..WEINMAN.. 10/03/2025  
   
PREV DISCUSSION
 
/ISSUED 1130 AM CDT FRI OCT 03 2025/  
   
..GREAT BASIN AND INTERMOUNTAIN WEST
 
 
A PROMINENT WESTERN STATES UPPER TROUGH, CENTERED OVER THE SIERRA AT  
MIDDAY, WILL CONTINUE TO PROGRESS EASTWARD TOWARD/OVER THE GREAT  
BASIN, WHILE TAKING ON AN INCREASINGLY NEUTRAL TILT. CONSEQUENTIAL  
HEIGHT FALLS, COOLING ALOFT, AND A STRENGTHENING OF DEEP-LAYER WINDS  
WILL OCCUR IN ASSOCIATION. THIS WILL SUPPORT INCREASING AND AT LEAST  
WIDELY SCATTERED THUNDERSTORM DEVELOPMENT INTO THE AFTERNOON AND  
TONIGHT AS LOW/MID-LEVEL LAPSE RATES STEEPEN AND MODEST  
DESTABILIZATION OCCURS. EVEN WITH LIMITED BUOYANCY, HIGH-BASED  
STORMS COMBINED WITH MODERATE LOW/MID-LEVEL FLOW COULD STILL RESULT  
IN A FEW STRONG THUNDERSTORM-ENHANCED SURFACE WIND GUSTS, WITH THE  
RELATIVELY GREATEST CHANCE FOR A FEW GUSTS THIS AFTERNOON/EARLY  
EVENING ACROSS NORTHERN/EAST-CENTRAL UTAH. PERSISTENT FORCING FOR  
ASCENT WILL RESULT IN THUNDERSTORM DEVELOPMENT THROUGHOUT THE  
EVENING AND OVERNIGHT AMID STRENGTHENING MID-LEVEL FLOW AND COOLING  
MID-LEVEL TEMPERATURES. BUOYANCY WILL REMAIN MODEST, BUT A FEW  
INSTANCES OF MOSTLY SUB-SEVERE HAIL MAY ALSO OCCUR.  
 

 
 
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