318  
ACUS01 KWNS 221626  
SWODY1  
SPC AC 221624  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1124 AM CDT TUE SEP 22 2026  
 
VALID 221630Z - 231200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR MUCH OF UTAH  
INTO ADJACENT PARTS OF WYOMING AND COLORADO...AND ACROSS A PORTION  
OF THE SOUTHEAST...  
   
..SUMMARY  
 
AN ISOLATED THREAT FOR SEVERE WIND GUSTS IS EXPECTED TODAY IN UTAH  
INTO SOUTHWEST WYOMING AND WESTERN COLORADO. THUNDERSTORMS CAPABLE  
OF STRONG TO LOCALLY SEVERE DAMAGING GUSTS ARE ALSO POSSIBLE ACROSS  
PARTS OF THE SOUTHEAST.  
   
..UTAH INTO SOUTHWEST WYOMING AND WESTERN COLORADO  
 
RECENT WATER-VAPOR IMAGERY SHOWS A POTENT SHORTWAVE TROUGH OVER THE  
WESTERN GREAT BASIN. RECENT MESOANALYSIS ESTIMATES A BELT OF  
STRONGER MID-LEVEL FLOW EXTENDS THROUGHOUT THE EASTERN PERIPHERY OF  
THIS WAVE FROM NORTHERN AZ INTO CENTRAL UT. THIS SHORTWAVE IS  
FORECAST TO CONTINUE SLOWLY NORTHEASTWARD TODAY, WITH THE  
ACCOMPANYING BELT OF STRONGER FLOW EXTENDING THROUGH NORTHERN UT  
INTO WESTERN WY. SCATTERED TO NUMEROUS THUNDERSTORMS ARE EXPECTED  
THIS AFTERNOON AND EVENING ACROSS THE REGION AS LIFT ATTENDANT TO  
THIS WAVE INTERACTS WITH THE MODESTLY MOIST AND BUOYANT AIRMASS  
ACROSS THE REGION. BUOYANCY WILL LIKELY REMAIN MODEST (I.E. MLCAPE  
LESS THAN 1000 J/KG. EVEN SO, MODERATE TO STRONG VERTICAL SHEAR  
ASSOCIATED WITH THE STRONGER MID-LEVEL FLOW WILL SUPPORT ORGANIZED  
STORM STRUCTURES. THIS SHEAR COMBINED WITH COLD MID-LEVEL  
TEMPERATURES WILL SUPPORT THE POTENTIAL FOR LARGE HAIL.  
ADDITIONALLY, HIGH CLOUD BASES AND STEEP LOW-LEVEL LAPSE RATES  
SUGGEST STRONG GUSTS ARE POSSIBLE WITH ANY OF THE MORE ROBUST  
STORMS. THIS ACTIVITY WILL EVENTUALLY MOVE INTO WESTERN CO AND  
SOUTHWEST WY TOWARDS THE LATE AFTERNOON/EARLY EVENING WITH ISOLATED  
SEVERE GUSTS AND/OR LARGE HAIL REMAINING POSSIBLE WITHIN THE  
STRONGER CORES AND ASSOCIATED OUTFLOWS.  
   
..SOUTHEAST  
 
RECENT SURFACE ANALYSIS PLACES A DIFFUSE COLD FRONT FROM THE  
ARKLATEX NORTHEAST INTO FAR WESTERN VA WHERE IT INTERSECTS THE WEDGE  
FRONT OVER THE MID-ATLANTIC. THIS FRONT IS EXPECTED TO GRADUALLY  
SHIFT SOUTHWARD TODAY, INTERACTING WITH THE MOIST AIRMASS ACROSS THE  
SOUTHEAST TO SUPPORT THUNDERSTORM DEVELOPMENT. THE STRONGEST  
BUOYANCY (I.E. 1500 TO 2000 J/KG OF MLCAPE) IS EXPECTED FROM  
WESTERN/CENTRAL SC INTO CENTRAL AL, WHERE AFTERNOON TEMPERATURES  
WILL LIKELY REACH THE 90S AMID LOW 70S DEWPOINTS. WEAK LOW TO MID  
TROPOSPHERIC FLOW WAS SAMPLED BY REGIONAL SOUNDINGS, WITH THE VERY  
WEAK VERTICAL SHEAR LIMITING THE OVERALL STORM STRENGTH AND  
PERSISTENCE. SOME OF THE STRONGER WATER-LOADED DOWNDRAFTS COULD  
PRODUCE STRONG GUSTS WITH POCKETS OF WIND DAMAGE INTO THE EARLY  
EVENING. LOW WIND PROBABILITIES WERE TRIMMED OUT OF SOUTHWEST VA AND  
ADJACENT WESTERN NC/NORTHEAST TN WHERE TEMPERATURES WILL REMAIN  
COOL, LIMITING BUOYANCY. LOW WIND PROBABILITIES WERE ALSO TRIMMED  
ACROSS CENTRAL MS WHERE ONLY ISOLATED STORM COVERAGE IS ANTICIPATED.  
 
..MOSIER/WENDT.. 09/22/2026  
 
 
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