624  
ACUS01 KWNS 161244  
SWODY1  
SPC AC 161242  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0742 AM CDT SUN AUG 16 2026  
 
VALID 161300Z - 171200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE OHIO VALLEY...CENTRAL APPALACHIANS...MID-ATLANTIC...AND CENTRAL  
HIGH PLAINS...  
   
..SUMMARY  
 
THUNDERSTORMS WITH DAMAGING WIND GUSTS WILL BE POSSIBLE FROM THIS  
AFTERNOON INTO EARLY EVENING OVER PARTS OF THE OHIO VALLEY AND  
MID-ATLANTIC. LARGE HAIL AND ISOLATED SEVERE WIND GUSTS WILL ALSO BE  
POSSIBLE IN PARTS OF THE CENTRAL HIGH PLAINS.  
   
..LOWER MO VALLEY THROUGH THE OH VALLEY INTO THE MID-ATLANTIC  
 
SATELLITE AND REGIONAL RADAR IMAGERY SHOWS SEVERAL VORTICITY MAXIMA  
EMBEDDED WITHIN THE MODERATE WESTERLY FLOW ALOFT THAT EXTENDS FROM  
THE CENTRAL PLAINS ACROSS THE OH VALLEY AND INTO THE MID-ATLANTIC.  
THE STRONGEST VORTICITY MAXIMUM IS CURRENTLY MOVING THROUGH  
NORTH-CENTRAL KS AND SOUTH-CENTRAL NE, WHILE MORE SUBTLE MAXIMA  
EXIST ACROSS WESTERN IL, SOUTHWESTERN LOWER MI/FAR NORTHERN IN, AND  
WESTERN PA. EACH OF THESE FEATURES WILL LIKELY CONTRIBUTE TO SHOWERS  
AND THUNDERSTORMS LATER TODAY. THE MOST CONSEQUENTIAL OF THESE  
STORMS WILL LIKELY OCCUR IN TANDEM WITH THE WESTERN IL AND  
SOUTHWESTERN LOWER MI WAVES AS THEY INTERACT WITH A MOIST AND  
DIURNALLY DESTABILIZED AIRMASS FROM THE MIDDLE OH VALLEY INTO THE  
MID-ATLANTIC. AIRMASS DESTABILIZATION APPEARS LIKELY BY THE EARLY  
AFTERNOON, WITH RENEWED THUNDERSTORM DEVELOPMENT ANTICIPATED FROM  
SOUTHEAST LOWER MI INTO SOUTHERN IN. MODERATE VERTICAL SHEAR WILL BE  
IN PLACE, SUPPORTING A PREDOMINANTLY MULTICELLULAR MODE. MID-LEVEL  
WINDS MAY INCREASE SLIGHTLY THROUGHOUT THE AFTERNOON, AND A  
SUPERCELL OR TWO IS POSSIBLE OVER SOUTHERN OH. A TREND TOWARDS  
CLUSTERING AND THE DEVELOPMENT OF LINEAR SEGMENTS IS ANTICIPATED  
OVER TIME, WITH DAMAGING GUSTS AS THE PRIMARY RISK THROUGHOUT THE  
DAY.  
 
THESE STORMS WILL CONTINUE EASTWARD ACROSS WV INTO MID-ATLANTIC  
DURING THE LATE AFTERNOON/EARLY EVENING. MODERATE BUOYANCY WILL  
SUPPORT STORM PERSISTENCE AND THE POTENTIAL FOR CONTINUED DAMAGING  
GUSTS. ADDITIONAL THUNDERSTORM DEVELOPMENT IS POSSIBLE AHEAD OF  
THESE CLUSTERS IN AREAS OF LOW-LEVEL CONVERGENCE DURING THE  
AFTERNOON. MODERATE VERTICAL SHEAR COULD SUPPORT A FEW MORE  
ORGANIZED STORMS, WITH WATER-LOADED DOWNBURSTS AS THE PRIMARY SEVERE  
RISK. A TORNADO OR TWO IS ALSO POSSIBLE, PARTICULARLY ACROSS  
NORTHERN VA WHERE SOUTHERLY SURFACE WINDS COULD RESULT IN ADEQUATE  
LOW-LEVEL HODOGRAPH CURVATURE.  
 
FARTHER WEST (ACROSS THE LOWER MO VALLEY), THE WELL-DEFINED  
VORTICITY MAXIMUM CURRENTLY OVER NORTH-CENTRAL KS/SOUTHERN-CENTRAL  
NE IS FORECAST TO BE EAST OF THE REGION BY THE LATE AFTERNOON, BUT  
AIRMASS DESTABILIZATION IN ITS WAKE IS UNCERTAIN. IF THE AIRMASS CAN  
RECOVER, ADDITIONAL THUNDERSTORMS ARE LIKELY ALONG A COLD FRONT  
MOVING INTO THE REGION THIS EVENING. STRONG BUOYANCY WILL SUPPORT  
ROBUST UPDRAFTS, BUT MODEST VERTICAL SHEAR WILL KEEP STORM  
ORGANIZATION LIMITED. IF THUNDERSTORMS FORM, A FEW STRONG GUSTS ARE  
POSSIBLE ACROSS THIS REGION THIS EVENING.  
   
..NORTHERN/CENTRAL HIGH PLAINS  
 
SCATTERED THUNDERSTORM DEVELOPMENT IN ANTICIPATED THIS AFTERNOON  
ACROSS THE NORTHERN AND CENTRAL HIGH PLAINS. THUNDERSTORMS OVER THE  
NORTHERN HIGH PLAINS WILL BE SUPPORTED BY LOW-LEVEL CONVERGENCE  
ALONG THE WESTERN EDGE OF THE MOIST AIRMASS OVER THE PLAINS.  
MODERATE VERTICAL SHEAR COULD SUPPORT A FEW SUPERCELLS CAPABLE OF  
HAIL AND STRONG GUSTS, BUT MODEST BUOYANCY SHOULD KEEP THE OVERALL  
SEVERE THREAT ISOLATED.  
 
THUNDERSTORM DEVELOPMENT FARTHER SOUTH ACROSS THE CENTRAL HIGH  
PLAINS WILL RESULT FROM A COMBINATION OF MOIST LOW-LEVEL EASTERLIES,  
WESTERLY FLOW ALOFT AND OROGRAPHIC EFFECTS. HERE, MORE CELLULAR  
DEVELOPMENT OVER THE HIGH TERRAIN AND IMMEDIATE FOOTHILLS COULD POSE  
A RISK FOR LARGE HAIL BEFORE TRANSITIONING TOWARDS MORE LINEAR  
STRUCTURES WITH STRONG GUSTS AS THE PRIMARY SEVERE RISK.  
 
..MOSIER/DEAN.. 08/16/2026  
 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab SPC Page
Main Text Page