483  
ACUS03 KWNS 210730  
SWODY3  
SPC AC 210729  
 
DAY 3 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0229 AM CDT THU AUG 21 2025  
 
VALID 231200Z - 241200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST  
 
   
..SUMMARY  
 
SEVERE THUNDERSTORM POTENTIAL CURRENTLY APPEARS LOW ON SATURDAY.  
 
...PARTS OF THE MIDWEST/LOWER GREAT LAKES INTO THE SOUTH-CENTRAL  
PLAINS...  
A MID/UPPER-LEVEL TROUGH IS FORECAST TO GRADUALLY AMPLIFY ACROSS THE  
NORTH-CENTRAL AND EASTERN CONUS SATURDAY. A COLD FRONT WILL CONTINUE  
MOVING SOUTHEASTWARD ACROSS PARTS OF THE GREAT LAKES/MIDWEST INTO  
THE SOUTH-CENTRAL PLAINS. MIDLEVEL LAPSE RATES ALONG/AHEAD OF THE  
FRONT WILL GENERALLY BE WEAK, BUT LOW-LEVEL MOISTURE WILL BE  
SUFFICIENT FOR MODERATE BUOYANCY BY AFTERNOON. THE STRONGEST  
DEEP-LAYER FLOW/SHEAR WILL LOCATED ACROSS PARTS OF THE CENTRAL GREAT  
LAKES, BUT THE CONVECTIVE SIGNAL IN MOST GUIDANCE IS RATHER SPARSE  
ACROSS THIS AREA, LIKELY DUE TO LIMITED FRONTAL CONVERGENCE AND VERY  
DRY AIR ALOFT. THE 00Z NAM IS A NOTABLE OUTLIER, DEPICTING BOTH A  
MUCH SLOWER FRONT, AND MORE SUBSTANTIAL DEVELOPMENT ALONG/AHEAD OF  
THE FRONT DURING THE AFTERNOON AND EVENING. SEVERE PROBABILITIES MAY  
EVENTUALLY BE NEEDED IF TRENDS END UP SUPPORTING MORE ROBUST  
CONVECTION ALONG/AHEAD OF THE FRONT ACROSS THE MIDWEST AND GREAT  
LAKES.  
 
FARTHER SOUTHWEST, ISOLATED TO WIDELY SCATTERED STORMS WILL BE  
POSSIBLE ACROSS PARTS OF THE OZARKS AND SOUTH-CENTRAL PLAINS. WHILE  
A STRONG STORM OR TWO WILL BE POSSIBLE IN THIS AREA, RELATIVELY WEAK  
DEEP-LAYER FLOW/SHEAR AND GENERALLY MODEST INSTABILITY MAY TEND TO  
LIMIT ORGANIZED SEVERE POTENTIAL.  
   
..CO FRONT RANGE AND ADJACENT PARTS OF THE HIGH PLAINS  
 
SCATTERED THUNDERSTORMS WILL AGAIN BE POSSIBLE ACROSS PARTS OF THE  
CO FRONT RANGE AND ADJACENT HIGH PLAINS SATURDAY. WHILE WIND  
PROFILES WILL REMAIN FAVORABLE FOR ORGANIZED CONVECTION, WITH  
MODESTLY ELONGATED HODOGRAPHS WITHIN THE POST-FRONTAL REGIME,  
GUIDANCE GENERALLY DEPICTS WEAKER MIDLEVEL LAPSE RATES COMPARED TO  
PREVIOUS DAYS, ESPECIALLY ACROSS THE HIGH PLAINS. THERE MAY BE A  
TENDENCY FOR STORMS TO REMAIN CONFINED TO THE HIGHER TERRAIN FOR  
MUCH OF THE PERIOD, WITH UNCERTAIN SEVERE POTENTIAL. HOWEVER, A  
MARGINAL SUPERCELL OR TWO WITH HAIL POTENTIAL CANNOT BE RULED OUT,  
AND SEVERE PROBABILITIES MAY EVENTUALLY BE NEEDED FOR SOME PART OF  
THIS REGION, IF TRENDS SUPPORT SUFFICIENT DESTABILIZATION.  
 
..DEAN.. 08/21/2025  
 
 
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