580  
ACUS48 KWNS 070900  
SWOD48  
SPC AC 070858  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0358 AM CDT SUN SEP 07 2025  
 
VALID 101200Z - 151200Z  
   
..DISCUSSION
 
 
THE MID-LEVEL FLOW PATTERN ACROSS THE US IS FORECAST TO BECOME MORE  
STAGNANT INTO THE EXTENDED-RANGE FORECAST PERIOD AS THE WESTERN US  
UPPER LOW DEEPENS AND SHORTWAVE RIDGING OVER THE PLAINS MOVES SLOWLY  
EASTWARD. BROAD TROUGHING OVER THE EAST SHOULD GRADUALLY  
CONSOLIDATE, SLOWING EASTWARD PROGRESS OF THE UPPER RIDGE. AS THE  
WESTERN TROUGH SLOWLY APPROACHES THE ROCKIES, A LEE TROUGH SHOULD  
SHARPEN EACH AFTERNOON WITH A NARROW ZONE OF MOISTURE RETURN ALONG  
AND EAST INTO PARTS OF THE HIGH PLAINS. SUFFICIENT DESTABILIZATION  
IS EXPECTED TO SUPPORT ISOLATED THUNDERSTORMS, AND PERHAPS SOME  
SEVERE RISK, NEAR THE LEE TROUGH AS SMALLER EMBEDDED PERTURBATIONS  
EJECT EASTWARD PERIODICALLY. HOWEVER, WITH ONLY SLOW MOVEMENT OF THE  
UPPER RIDGE EXPECTED, FORCING FOR ASCENT SHOULD REMAIN MODEST UNTIL  
EARLY NEXT WEEKEND. SOMEWHAT GREATER SEVERE POTENTIAL MAY DEVELOP  
D6/FRIDAY OR D7/SATURDAY AS THE PRIMARY UPPER TROUGH BEGINS TO  
EMERGE OVER THE PLAINS. HOWEVER, GIVEN THE UNCERTAINTIES ASSOCIATED  
WITH THE SMALLER SCALE FEATURES, AND THE TIMING OF THE MAIN TROUGH,  
LIMITED CONFIDENCE EXISTS REGARDING SEVERE POTENTIAL IN THE EXTENDED  
FORECAST.  
 
..LYONS.. 09/07/2025  
 
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