523  
ACUS03 KWNS 130730  
SWODY3  
SPC AC 130729  
 
DAY 3 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0229 AM CDT THU AUG 13 2026  
 
VALID 151200Z - 161200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL  
HIGH PLAINS INTO PARTS OF THE MIDWEST AND OHIO  
VALLEY...SOUTHERN/CENTRAL APPALACHIANS...AND CAROLINAS...  
   
..SUMMARY  
 
STRONG TO LOCALLY SEVERE STORMS ARE POSSIBLE ON SATURDAY FROM THE  
CENTRAL HIGH PLAINS EASTWARD INTO PARTS OF THE MIDWEST, OHIO VALLEY,  
SOUTHERN/CENTRAL APPALACHIANS, AND CAROLINAS.  
   
..SYNOPSIS  
 
AN UPPER RIDGE IS FORECAST TO REMAIN ANCHORED OVER PARTS OF THE  
SOUTHERN PLAINS AND LOWER MS VALLEY VICINITY ON SATURDAY. A  
WARM-FRONTAL ZONE INITIALLY EXTENDING FROM IA INTO THE OH VALLEY IS  
FORECAST TO MOVE NORTHWARD AS A WARM FRONT, WHILE THE WESTERN  
EXTENSION OF THIS FRONT MAY REMAIN NEARLY STATIONARY ACROSS THE  
CENTRAL PLAINS. FARTHER NORTH, A WEAK SURFACE LOW IS FORECAST TO  
MOVE ACROSS NORTHERN MN, AS A TRAILING COLD FRONT BEGINS TO MOVE  
SOUTHEASTWARD ACROSS PARTS OF THE DAKOTAS AND EVENTUALLY INTO PARTS  
OF MN/IA/NE.  
 
...CENTRAL HIGH PLAINS EASTWARD INTO PARTS OF THE MIDWEST/OHIO  
VALLEY...  
ANOTHER DAY OF AT LEAST ISOLATED SEVERE POTENTIAL IS EVIDENT ON  
SATURDAY ALONG THE PERIPHERY OF THE UPPER RIDGE. HOWEVER,  
PREDICTABILITY IS TYPICALLY LOW REGARDING THE DETAILS WITHIN THIS  
REGIME, AND GENERALLY MODEST MIDLEVEL LAPSE RATES AND DEEP-LAYER  
SHEAR MAY TEND TO LIMIT THE MAGNITUDE OF SEVERE POTENTIAL. A BROAD  
LEVEL-1/MARGINAL RISK HAS BEEN INCLUDED WHERE THE GREATEST RELATIVE  
SEVERE POTENTIAL IS CURRENTLY EXPECTED, THOUGH CONFIDENCE IN THE  
DETAILS IS LOW.  
 
DESPITE THE RELATIVELY MODEST LAPSE RATES, RICH LOW-LEVEL MOISTURE  
WILL AGAIN SUPPORT MODERATE TO STRONG BUOYANCY NEAR AND NORTH OF THE  
FRONT EXTENDING FROM THE CENTRAL HIGH PLAINS INTO PARTS OF THE  
MIDWEST/OHIO VALLEY. GIVEN THE GENERALLY MODEST DEEP-LAYER  
FLOW/SHEAR AND NEBULOUS LARGE-SCALE ASCENT, ANY GREATER ORGANIZED  
SEVERE POTENTIAL MAY BE DEPENDENT ON OPTIMALLY TIMED MCVS MOVING  
ALONG THE PERIPHERY OF THE RIDGE.  
 
EARLY-DAY CONVECTION ACROSS IA/MO MAY POSE SOME SEVERE THREAT,  
ESPECIALLY IF ANY STORM CLUSTER IS ABLE TO PROPAGATE ALONG THE  
FRONTAL ZONE INTO PARTS OF THE OH VALLEY. SOME GUIDANCE SUGGESTS  
THAT AN MCV MAY DEVELOP ACROSS THE CENTRAL HIGH PLAINS LATE  
D2/FRIDAY AND MOVE EAST-NORTHEASTWARD ACROSS PARTS OF NE/IA/SOUTHERN  
MN THROUGH THE DAY SATURDAY, WHICH MAY AID IN STORM DEVELOPMENT  
NEAR/NORTH OF THE FRONT DURING THE AFTERNOON/EVENING.  
 
FARTHER WEST, DIURNAL STORM DEVELOPMENT IS AGAIN EXPECTED IN THE CO  
FRONT RANGE VICINITY, WHICH COULD RESULT IN SOME STORM CLUSTERING AS  
CONVECTION MOVES ACROSS THE CENTRAL HIGH PLAINS SATURDAY NIGHT.  
GIVEN THE FAVORABLE LOW-LEVEL MOISTURE AND BUOYANCY, THE STRONGEST  
STORMS WITHIN ANY OF THESE REGIMES COULD POSE A THREAT FOR DAMAGING  
WINDS AND PERHAPS ISOLATED HAIL, THOUGH IT IS ALSO POSSIBLE THAT THE  
BULK OF CONVECTION REMAINS SOMEWHAT DISORGANIZED, DUE TO RELATIVELY  
WEAK DEEP-LAYER FLOW/SHEAR.  
   
..SOUTHERN/CENTRAL APPALACHIANS AND CAROLINAS  
 
MODEST NORTHWESTERLY MID/UPPER-LEVEL FLOW WILL OVERSPREAD A MOIST  
AND MODERATELY UNSTABLE ENVIRONMENT ACROSS PARTS OF THE  
SOUTHERN/CENTRAL APPALACHIANS AND CAROLINAS DURING THE AFTERNOON. A  
FEW STRONGER CELLS/CLUSTERS CAPABLE OF DAMAGING WIND WILL BE  
POSSIBLE WITHIN THIS REGIME.  
 
..DEAN.. 08/13/2026  
 
 
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