799  
ACUS03 KWNS 211913  
SWODY3  
SPC AC 211912  
 
DAY 3 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0212 PM CDT THU AUG 21 2025  
 
VALID 231200Z - 241200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST  
 
   
..SUMMARY  
 
SEVERE THUNDERSTORM POTENTIAL CURRENTLY APPEARS LOW ON SATURDAY.  
   
..CENTRAL HIGH PLAINS INTO LOWER MI VICINITY  
 
THE UPPER CYCLONE OVER ONTARIO WILL DEEPEN MODESTLY BUT MOSTLY  
REMAIN STATIONARY, WHILE AN ATTENDANT SHORTWAVE TROUGH DEEPENS  
ACROSS THE MIDWEST ON SATURDAY. STRONGER WESTERLY FLOW WILL BE IN  
PLACE ACROSS THE UPPER MIDWEST/GREAT LAKES AS A SURFACE COLD FRONT  
DEVELOPS EAST/SOUTHEAST ACROSS MI AND MUCH OF THE MS/OH VALLEYS AND  
PORTIONS OF THE SOUTHERN PLAINS. A SEASONALLY MOIST AIRMASS WILL BE  
IN PLACE AHEAD OF THE COLD FRONT, WITH POCKETS OF MODEST  
DESTABILIZATION EXPECTED FROM THE CENTRAL HIGH PLAINS INTO THE LOWER  
MI VICINITY. GENERALLY WEAK MIDLEVEL LAPSE RATES AND POOR FRONTAL  
CONVERGENCE WILL LIMIT THUNDERSTORM COVERAGE, BUT A FEW STORMS COULD  
DEVELOP ACROSS LOWER MI AND PERHAPS PARTS OF IN/OH. GUSTY WINDS  
COULD ACCOMPANY THESE STORMS, BUT OVERALL SEVERE POTENTIAL APPEARS  
LOW.  
 
ADDITIONAL THUNDERSTORMS ALSO WILL DEVELOP OVER HIGHER TERRAIN IN  
PARTS OF SOUTHEAST WY INTO EASTERN CO, SOUTHWARD TOWARD THE RATON  
MESA VICINITY, AND PERHAPS EASTWARD INTO NORTHERN OK NEAR THE  
FRONTAL BOUNDARY. THE BEST CHANCE FOR A STRONG STORM OR TWO APPEARS  
TO BE OVER EASTERN CO IN THE POST-FRONTAL UPSLOPE REGIME WHERE  
AROUND 1000 J/KG MLCAPE WILL BE PRESENT AMID SUPERCELL WIND PROFILES  
AND STEEP LAPSE RATES. MODEST WARMING NEAR 700 MB MAY SUPPRESS  
UPDRAFT INTENSITY, ESPECIALLY AMID WEAK LARGE-SCALE ASCENT. IF A  
STRONGER STORM CAN BE MAINTAINED OFF OF THE HIGHER TERRAIN, STRONG  
GUSTS AND HAIL COULD OCCUR. HOWEVER, CONFIDENCE IN THIS SCENARIO IS  
LOW, PRECLUDING SEVERE PROBABILITIES.  
 
..LEITMAN.. 08/21/2025  
 
 
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