314  
ACUS01 KWNS 210536  
SWODY1  
SPC AC 210535  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1235 AM CDT MON SEP 21 2026  
 
VALID 211200Z - 221200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF  
THE SOUTHEAST INTO THE SOUTHERN AND CENTRAL APPALACHIANS...  
   
..SUMMARY
 
 
THUNDERSTORMS WITH ISOLATED SEVERE WIND GUSTS WILL BE POSSIBLE THIS  
AFTERNOON FROM PARTS OF THE SOUTHEAST INTO THE SOUTHERN AND CENTRAL  
APPALACHIANS.  
   
..SOUTHEAST/SOUTHERN AND CENTRAL APPALACHIANS
 
 
A COLD FRONT WILL ADVANCE SOUTHEASTWARD ACROSS THE SOUTHERN AND  
EASTERN U.S. TODAY. BY AFTERNOON, THE FRONT IS FORECAST TO BE  
POSITIONED FROM NORTHERN MISSISSIPPI NORTHEASTWARD TO WESTERN  
VIRGINIA. AHEAD OF THE FRONT, A MOIST AIRMASS WILL BE IN PLACE WITH  
SURFACE DEWPOINTS IN THE UPPER 60S TO MID 70S F FROM THE LOWER  
MISSISSIPPI VALLEY NORTHEASTWARD INTO WEST VIRGINIA. AS SURFACE  
TEMPERATURE WARM, AN AXIS OF MODERATE INSTABILITY WILL DEVELOP AHEAD  
OF THE FRONT FROM CENTRAL MISSISSIPPI NORTHEASTWARD INTO WESTERN  
NORTH CAROLINA, WHERE MLCAPE SHOULD PEAK IN THE 2000 TO 3000 J/KG  
RANGE. LOW-LEVEL CONVERGENCE WILL INCREASE ALONG THE FRONT DURING  
THE DAY, WHICH WILL BE FAVORABLE FOR SCATTERED TO NUMEROUS  
THUNDERSTORM DEVELOPMENT. ALTHOUGH DEEP-LAYER SHEAR WILL BE WEAK  
ALONG AND NEAR THE INSTABILITY AXIS, LOW-LEVEL LAPSE RATES WILL  
BECOME STEEP IN THE AFTERNOON. THE THERMODYNAMIC ENVIRONMENT SHOULD  
BE FAVORABLE FOR ISOLATED SEVERE WIND GUSTS WITH SINGLE CELLS OR  
DISORGANIZED MULTICELLS. THE THREAT SHOULD BE LARGELY DIURNAL BUT  
MAY PERSIST INTO THE EARLY EVENING IN AREAS THAT DESTABILIZE THE  
MOST.  
 
..BROYLES/THORNTON.. 09/21/2026  
 

 
 
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