842  
ACUS01 KWNS 211627  
SWODY1  
SPC AC 211625  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1125 AM CDT MON SEP 21 2026  
 
VALID 211630Z - 221200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF  
THE SOUTHEAST INTO CENTRAL APPALACHIANS...AND OVER THE TEXAS SOUTH  
PLAINS...  
   
..SUMMARY  
 
ISOLATED DAMAGING WIND GUSTS ARE POSSIBLE THIS AFTERNOON FROM PARTS  
OF THE SOUTHEAST INTO THE SOUTHERN AND CENTRAL APPALACHIANS. AN  
ISOLATED RISK FOR LARGE HAIL AND SEVERE GUSTS IS FORECAST OVER PARTS  
OF THE TEXAS SOUTH PLAINS LATER TODAY.  
   
..SOUTHEAST/SOUTHERN AND CENTRAL APPALACHIANS  
 
RECENT RADAR AND SATELLITE IMAGERY REVEALS A TRIO OF MCVS OVER THE  
OH VALLEY, WITH PERHAPS ANOTHER MCV FARTHER SOUTHWEST IN THE  
MID-SOUTH VICINITY. THESE VORTICITY MAXIMA ARE NORTH/WEST OF AN  
ARCING COLD FRONT THAT EXTENDS FROM SOUTHERN VA WEST-NORTHWEST INTO  
NORTHERN KY AND THEN BACK SOUTHWESTWARD THROUGH NORTHERN AR AND  
CENTRAL OK INTO THE TX SOUTH PLAINS. A MOIST AIRMASS PERSISTS SOUTH  
OF THIS BOUNDARY, WITH DEWPOINTS IN THE LOW 70S ACROSS MUCH OF  
SOUTHEAST, TN VALLEY, AND CAROLINAS. THE FRONT IS FORECAST TO SLOWLY  
SHIFT SOUTHWARD TODAY, INTERACTING WITH THE MOIST, DIURNALLY  
DESTABILIZED, AND MODERATELY BUOYANT AIRMASS TO SUPPORT SCATTERED  
THUNDERSTORMS. VERTICAL SHEAR WILL BE WEAK, AND LARGELY  
MULTICELLULAR, OUTFLOW-DOMINANT STORM MODE IS ANTICIPATED. EVEN SO,  
AMPLE MOISTURE IS IN PLACE (I.E. PW VALUES OVER 2" SAMPLED ON THE  
12Z BMX SOUNDING), AND SPORADIC STRONGER DOWNDRAFTS MAY YIELD A  
STRONG TO LOCALLY SEVERE GUSTS (50 TO 60 MPH). HIGHEST THUNDERSTORM  
COVERAGE IS EXPECTED FROM SOUTHEAST TN AND NORTHWEST GA THROUGH  
NORTHERN AL INTO CENTRAL/SOUTHERN MS AND EASTERN LA.  
   
..TX SOUTH PLAINS INTO NORTH-CENTRAL/NORTHEAST TX  
 
WESTERN PERIPHERY OF THE FRONT DESCRIBED IN THE PREVIOUS SECTION  
INTERSECTS A WEAK LOW OVER FAR SOUTHEAST NM. A MOIST AIRMASS EXISTS  
ALONG AND SOUTH OF THIS BOUNDARY, WITH DEWPOINTS RANGING FROM THE  
LOW 60S OVER THE TX SOUTH PLAINS TO THE LOW 70S ACROSS MUCH OF  
CENTRAL AND EASTERN TX. EASTERLY FLOW WILL HELP MAINTAIN THIS  
MOISTURE AMID STRONG HEATING OVER THE TX SOUTH PLAIN VICINITY,  
CONTRIBUTING TO AIRMASS DESTABILIZATION AND MODERATE BUOYANCY BY  
THIS AFTERNOON. LOW-LEVEL CONVERGENCE ALONG THE FRONT (AND/OR  
RESIDUAL OUTFLOW) AND NEAR THE SURFACE LOW WILL LIKELY RESULT IN  
SCATTERED THUNDERSTORM DEVELOPMENT. VERTICAL SHEAR WILL BE MODEST,  
BUT ANY STRONGER, MORE PERSISTENT THUNDERSTORMS MAY YIELD AN  
ISOLATED RISK FOR LARGE HAIL/SEVERE GUSTS BEFORE DISSIPATING DURING  
THE EVENING.  
 
A SECONDARY AREA OF HIGHER THUNDERSTORM COVERAGE APPEARS LIKELY OVER  
NORTHEAST TX THIS AFTERNOON/EVENING. HERE, DIFFERENTIAL HEATING  
AND/OR OUTFLOW FROM ONGOING THUNDERSTORMS COULD RESULT IN AN AREA OF  
INCREASED LOW-LEVEL CONVERGENCE WITHIN A WARM, MOIST, AND MODERATELY  
UNSTABLE AIRMASS THIS AFTERNOON. ISOLATED WATER-LOADED DOWNBURSTS  
CAPABLE OF PRODUCING DAMAGING WIND GUSTS ARE POSSIBLE. ANTICIPATED  
LIMITED SEVERE COVERAGE PRECLUDES INTRODUCING LOW WIND PROBABILITIES  
IN THIS AREA.  
 
..MOSIER/CHALMERS.. 09/21/2026  
 
 
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