578  
ACUS48 KWNS 090901  
SWOD48  
SPC AC 090859  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0359 AM CDT TUE SEP 09 2025  
 
VALID 121200Z - 171200Z  
   
..DISCUSSION  
 
AS SHORTWAVE RIDGING BEGINS TO BREAKDOWN INTO THIS WEEKEND, THE  
UPPER TROUGH AND ENHANCED SOUTHWESTERLY FLOW OVER THE ROCKIES WILL  
FINALLY BEGIN TO OVERSPREAD THE PLAINS D4/FRIDAY AND D5/SATURDAY.  
CONTINUED EAST/SOUTHEASTERLY LOW-LEVEL FLOW IS LIKELY OVER THE  
NORTHERN PLAINS AND UPPER MIDWEST, ALLOWING FOR THE RETURN OF RICHER  
SURFACE MOISTURE. A STALLED FRONT EXTENDING EASTWARD FROM THE LEE  
LOW OVER THE DAKOTAS INTO THE WESTERN GREAT LAKES MAY SERVE AS A  
FOCUS FOR STORM DEVELOPMENT ACROSS THE DAKOTAS AND MN. HOWEVER,  
MODELS VARY ON THE DEGREE OF MOISTURE AND RESULTING BUOYANCY NEAR  
THE LOW/FRONT, WHICH CASTS SIGNIFICANT UNCERTAINTY ON SEVERE  
POTENTIAL. ENHANCED SOUTHWESTERLY FLOW ALOFT COULD SUPPORT SOME  
ORGANIZED SEVERE THREAT, BUT CONFIDENCE IN SPECIFICS REMAINS TOO LOW  
FOR 15% PROBABILITIES.  
 
FARTHER SOUTH, SUFFICIENT DESTABILIZATION IS EXPECTED TO SUPPORT  
ISOLATED THUNDERSTORMS EACH AFTERNOON INTO THE CENTRAL AND SOUTHERN  
PLAINS. WHILE THE MAIN UPPER TROUGH SHOULD BEGIN TO WEAKEN LATER  
INTO THE WEEKEND, LINGERING MID-LEVEL FLOW COULD SUPPORT SOME SEVERE  
RISK WITHIN A HOT AND UNSTABLE AIR MASS ALONG A SURFACE TROUGH. BY  
EARLY NEXT WEEK, MID-LEVEL RIDGING IS EXPECTED TO REBUILD OVER THE  
CENTRAL CONUS KEEPING STRONGER FLOW ALOFT AND SEVERE POTENTIAL  
LIMITED FOR THE REMAINDER OF THE EXTENDED FORECAST PERIOD.  
 
..LYONS.. 09/09/2025  
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