048  
ACUS01 KWNS 090101  
SWODY1  
SPC AC 090059  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0759 PM CDT FRI AUG 08 2025  
 
VALID 090100Z - 091200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SD  
INTO MN AND NORTHWEST WI...AND ALSO ACROSS SOUTHWEST SD AND WESTERN  
NE...  
   
..SUMMARY  
 
SCATTERED SEVERE THUNDERSTORMS WITH DAMAGING WINDS, LARGE HAIL, AND  
POSSIBLY A TORNADO ARE EXPECTED TO DEVELOP THIS EVENING AND TONIGHT  
ACROSS PARTS OF THE UPPER MIDWEST AND THE CENTRAL HIGH PLAINS.  
   
..EASTERN DAKOTAS INTO MN/NORTHWEST WI  
 
SCATTERED TO WIDESPREAD STORM DEVELOPMENT IS STILL EXPECTED LATER  
THIS EVENING FROM THE FAR EASTERN DAKOTAS INTO MN, AS A SEASONABLY  
DEEP MID/UPPER-LEVEL SHORTWAVE TROUGH AND ATTENDANT COLD FRONT  
IMPINGE UPON A STRONGLY UNSTABLE ENVIRONMENT. A FEW SUPERCELLS COULD  
EVOLVE INITIALLY WITHIN A MODERATELY SHEARED ENVIRONMENT, WITH A  
THREAT OF HAIL AND POSSIBLY A TORNADO. DEEP-LAYER FLOW/SHEAR  
GENERALLY PARALLEL TO THE FRONT WILL LIKELY RESULT IN A QUICK  
TRANSITION TO A CLUSTER OR LINEAR MODE. THIS COULD LEAD TO AN  
INCREASING THREAT FOR DAMAGING WIND, THOUGH THERE MAY BE SOME  
TENDENCY FOR CONVECTION TO BECOME SLIGHTLY ANAFRONTAL WITH TIME.  
 
GUIDANCE SUGGESTS THE GREATEST RELATIVE THREAT FOR MORE ORGANIZED  
UPSCALE GROWTH WILL BE FROM CENTRAL INTO NORTHEAST MN, ALONG A  
DIFFUSE SURFACE BOUNDARY. THE LATE TIMING AND THE EFFECTS OF  
NOCTURNAL LOW-LEVEL STABILIZATION RESULTS IN SOME UNCERTAINTY  
REGARDING THE MAGNITUDE OF THE SEVERE-WIND THREAT, BUT A SWATH OF  
DAMAGING WIND REMAINS POSSIBLE INTO THE OVERNIGHT HOURS.  
   
..CENTRAL PLAINS VICINITY  
 
DEVELOPMENT OF A SUPERCELL OR TWO REMAINS POSSIBLE THIS EVENING  
WITHIN A POST-FRONTAL REGIME FROM SOUTHWEST SD INTO WESTERN NE,  
THOUGH COVERAGE REMAINS UNCERTAIN. ELONGATED HODOGRAPHS WOULD  
SUPPORT A HAIL THREAT WITH ANY SUSTAINED CELLS, WITH LOCALIZED  
SEVERE GUSTS ALSO POSSIBLE.  
 
SOME RECENT RUNS OF THE HRRR SUGGEST POST-FRONTAL DEVELOPMENT  
OVERNIGHT ACROSS PARTS OF SOUTHEAST WY AND NORTHEAST CO. WHILE THIS  
SCENARIO IS UNCERTAIN, THE ENVIRONMENT WILL BE FAVORABLE FOR  
ISOLATED HAIL AND STRONG GUSTS IF STORMS DEVELOP.  
 
A NEBULOUS BUT POTENTIALLY ORGANIZED SEVERE THREAT ALSO REMAINS  
EVIDENT OVERNIGHT ACROSS PARTS OF NE INTO NORTHERN IA, WITHIN A  
FAVORABLY UNSTABLE AND MODESTLY SHEARED ENVIRONMENT. STRONG ELEVATED  
STORMS WILL BE POSSIBLE AS THE FRONT MOVES INTO THE REGION, WITH  
SOME THREAT FOR HAIL AND LOCALIZED DAMAGING WINDS. ANY ORGANIZED  
CLUSTERING COULD RESULT IN A LOCALLY GREATER DAMAGING-WIND THREAT.  
   
..NORTHERN LOWER MI  
 
A STRONG STORM OR TWO REMAINS POSSIBLE THIS EVENING ACROSS NORTHERN  
LOWER MI, BEFORE CONVECTION WANES LATER TONIGHT AS CINH INCREASES.  
STEEP LAPSE RATES, MODERATE BUOYANCY, AND AROUND 30 KT OF EFFECTIVE  
SHEAR (AS NOTED ON THE 00Z APX SOUNDING) COULD CONTINUE TO SUPPORT A  
THREAT OF ISOLATED HAIL AND STRONG GUSTS BEFORE STORMS DIMINISH WITH  
TIME.  
 
..DEAN.. 08/09/2025  
 
 
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