441  
ACUS01 KWNS 160557  
SWODY1  
SPC AC 160556  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1256 AM CDT SUN AUG 16 2026  
 
VALID 161200Z - 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 SEVERE 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.  
   
..OHIO VALLEY/MID-ATLANTIC
 
 
A MID-LEVEL SHORTWAVE TROUGH, EMBEDDED IN WEST-NORTHWESTERLY FLOW,  
WILL MOVE THROUGH THE OHIO VALLEY TODAY. AHEAD OF THE SHORTWAVE  
TROUGH, A MOIST AIRMASS WILL BE IN PLACE FROM THE OHIO VALLEY  
SOUTHEASTWARD TO THE MID-ATLANTIC COAST. SURFACE DEWPOINTS ALONG  
THIS WEST-NORTHWEST TO EAST-SOUTHEAST CORRIDOR WILL BE IN THE 70S F,  
WHICH WILL CONTRIBUTE TO THE DEVELOPMENT OF MODERATE INSTABILITY BY  
MIDDAY. AT THE SURFACE, A COLD FRONT WILL ADVANCE EASTWARD INTO THE  
OHIO VALLEY, AS A PRE-FRONTAL TROUGH MOVES INTO THE CENTRAL  
APPALACHIANS. THESE TWO FEATURES WILL FOCUS CONVECTIVE DEVELOPMENT  
DURING THE DAY. A COMPLEX OF STORMS APPEARS LIKELY TO FORM OVER THE  
HIGHER TERRAIN IN WEST VIRGINIA, AND MOVE EAST-SOUTHEASTWARD INTO  
THE LOWER ELEVATIONS OF VIRGINIA AND MARYLAND DURING THE MID TO LATE  
AFTERNOON.  
 
RAP FORECAST SOUNDINGS FROM WEST VIRGINIA INTO THE VIRGINIA IN THE  
LATE AFTERNOON HAVE 0-6 KM SHEAR IN THE 25 TO 30 KNOT RANGE. SOME  
DIRECTIONAL SHEAR IS PRESENT IN THE LOW-LEVELS AND 0-3 KM LAPSE  
RATES ARE STEEP APPROACHING 7 C/KM. THIS ENVIRONMENT WILL SUPPORT A  
WIND-DAMAGE THREAT WITH ORGANIZED MULTICELLS. ISOLATED SUPERCELLS  
WITH SEVERE GUSTS WILL ALSO BE POSSIBLE. THE THREAT MAY CONTINUE  
INTO THE EARLY EVENING ACROSS PARTS OF THE MID-ATLANTIC.  
 
FURTHER WEST INTO PARTS OF THE LOWER OHIO VALLEY, A VERY MOIST  
AIRMASS WILL ALSO BE IN PLACE. SURFACE DEWPOINTS IN THE 70S F WILL  
CONTRIBUTE TO THE DEVELOPMENT OF MODERATE INSTABILITY. SCATTERED  
THUNDERSTORMS ARE EXPECTED TO FORM ALONG ZONES OF LOW-LEVEL  
CONVERGENCE DURING THE AFTERNOON. ALTHOUGH LARGE-SCALE ASCENT WILL  
BE WEAKER FURTHER WEST, THE THERMODYNAMIC ENVIRONMENT WILL BE  
SUFFICIENT FOR ISOLATED SEVERE GUSTS.  
   
..CENTRAL HIGH PLAINS
 
 
AT MID-LEVELS, A RIDGE WILL MOVE THROUGH THE INTERMOUNTAIN WEST  
TODAY AS FLOW REMAINS WESTERLY OVER MUCH OF THE CENTRAL U.S. AS  
SURFACE TEMPERATURES WARM, SCATTERED THUNDERSTORMS WILL DEVELOP IN  
THE FOOTHILLS OF THE CENTRAL ROCKIES. THESE STORMS WILL MOVE  
EASTWARD INTO THE LOWER ELEVATIONS OF EASTERN COLORADO AND WESTERN  
NEBRASKA. RAP FORECAST SOUNDINGS ACROSS THE CENTRAL HIGH PLAINS BY  
LATE AFTERNOON HAVE MODERATE INSTABILITY (MLCAPE AROUND 2500 J/KG),  
0-6 KM SHEAR NEAR 35 KNOTS AND 700 TO 500 MB LAPSE RATES IN THE 7 TO  
7.5 C/KM RANGE. THIS SHOULD SUPPORT A THREAT FOR LARGE HAIL AND  
ISOLATED SEVERE GUSTS WITH ROTATING STORMS AND ORGANIZED LINE  
SEGMENTS. THE THREAT WILL LIKELY PERSIST INTO THE EVENING ACROSS  
PARTS OF THE CENTRAL HIGH PLAINS.  
 
..BROYLES/LYONS.. 08/16/2026  
 

 
 
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