572  
ACUS02 KWNS 200547  
SWODY2  
SPC AC 200546  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1246 AM CDT SUN SEP 20 2026  
 
VALID 211200Z - 221200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF  
THE CENTRAL AND SOUTHERN APPALACHIANS...  
   
..SUMMARY  
 
A FEW INSTANCES OF DAMAGING GUSTS ARE POSSIBLE ACROSS THE CENTRAL  
AND SOUTHERN APPALACHIANS TO THE LOWER MISSISSIPPI VALLEY TOMORROW  
(MONDAY).  
   
..SYNOPSIS  
 
ZONAL FLOW WILL DOMINATE THE UPPER-AIR PATTERN ACROSS THE CONUS  
TOMORROW (MONDAY). MULTIPLE MID-LEVEL LOW-AMPLITUDE IMPULSES WILL  
TRAVERSE THE CENTRAL CONUS AS A LONGER WAVE UPPER TROUGH IMPINGES ON  
THE CA COASTLINE THROUGH THE PERIOD. THE PROGRESSION OF THE  
AFOREMENTIONED IMPULSES WILL ENCOURAGE THE SOUTHWARD ADVANCEMENT OF  
A SURFACE COLD FRONT, FROM TEXAS TO THE CENTRAL APPALACHIANS. GIVEN  
ADEQUATE MOISTURE AND ASSOCIATED INSTABILITY AHEAD OF THE FRONT, A  
FEW STRONG TO SEVERE STORMS ARE POSSIBLE, ESPECIALLY OVER THE  
CENTRAL AND SOUTHERN APPALACHIANS.  
   
..CENTRAL AND SOUTHERN APPALACHIANS TO THE LOWER MS VALLEY  
 
BY AFTERNOON PEAK HEATING, SURFACE DEWPOINTS WILL REACH THE UPPER  
60S TO LOW 70S F, WITH LITTLE TO NO MLCINH GIVEN A MIXED BOUNDARY  
LAYER. ACROSS THE CENTRAL/SOUTHERN APPALACHIANS TO THE SOUTHEAST,  
THUNDERSTORMS DEVELOPING ALONG AND AHEAD OF THE FRONT WILL HAVE  
ACCESS TO 1500-2000 J/KG OF TALL AND THIN MLCAPE. GIVEN MEDIOCRE  
SHEAR PROFILES, MAINLY PULSE-CELLULAR TO MULTICELLULAR COMPLEXES ARE  
EXPECTED, THE STRONGER OF WHICH MAY PRODUCE WET DOWNBURSTS CAPABLE  
OF CAUSING A FEW INSTANCES OF TREE/WIRE DAMAGE. THE BEST CHANCE FOR  
WIND DAMAGE WILL BE OVER THE CENTRAL/SOUTHERN APPALACHIANS, WHERE A  
RELATIVELY GREATER NUMBER OF STORMS MAY DEVELOP PER LATEST  
HIGH-RESOLUTION AND ML/AI GUIDANCE CONSENSUS.  
   
..PORTIONS OF WESTERN TEXAS  
 
ALONG THE WESTERN FLANK OF THE COLD FRONT, A COUPLE OF THUNDERSTORMS  
MAY DEVELOP OVER WESTERN TX, AMID A SUFFICIENTLY MOIST LOW-LEVEL  
AIRMASS TO SUPPORT STRONG THUNDERSTORMS. MID-LEVEL LAPSE RATES  
APPEAR MEDIOCRE, AND GIVEN WEAK UPPER SUPPORT, NO SEVERE  
PROBABILITIES WERE INTRODUCED THIS OUTLOOK DESPITE THE PRESENCE OF  
ELONGATED HODOGRAPHS. HOWEVER, SOME GUIDANCE HAS HINTED AT LOCALLY  
STRONGER MULTICELLULAR STORMS POSSIBLE. IF TRENDS CONTINUE TOWARD  
GREATER STORM COVERAGE, LOWER-END SEVERE PROBABILITIES (MAINLY FOR  
MARGINALLY SEVERE WIND/HAIL) MAY BE NEEDED IN FUTURE OUTLOOKS.  
 
..SQUITIERI.. 09/20/2026  
 
 
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