108  
ACUS01 KWNS 180454  
SWODY1  
SPC AC 180453  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1153 PM CDT FRI APR 17 2026  
 
VALID 181200Z - 191200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE  
UPPER OHIO VALLEY TO THE APPALACHIANS...  
   
..SUMMARY  
 
SCATTERED STRONG TO SEVERE THUNDERSTORMS CAPABLE OF DAMAGING WINDS  
AND HAIL WILL BE POSSIBLE ON SATURDAY ACROSS THE UPPER OHIO VALLEY  
AND CENTRAL APPALACHIANS. ISOLATED SEVERE HAIL IS ALSO POSSIBLE  
ACROSS PARTS OF CENTRAL TEXAS.  
   
..SYNOPSIS  
 
A LARGE UPPER TROUGH WITH ELONGATED LEADING SPEED MAX WILL SWEEP  
ACROSS THE GREAT LAKES AND OH VALLEY DURING THE DAY AND INTO THE  
APPALACHIANS BY SUNDAY MORNING. MEANWHILE, MODERATE WESTERLIES ALOFT  
WILL PERSIST ACROSS TX WITH THE AID OF A SUBTROPICAL JET.  
 
AT THE SURFACE, A COLD FRONT WILL MOVE ACROSS OH AND KY THROUGH  
EARLY AFTERNOON, AND INTO WESTERN NY, PA, AND WV LATE IN THE DAY.  
THIS FRONT WILL ALSO EXTEND FAR SOUTHWESTWARD TOWARD THE  
NORTHWESTERN GULF COAST AND INTO FAR SOUTHERN TX. AHEAD OF THE  
FRONT, A NARROW PLUME OF 50S TO LOWER 60S F DEWPOINTS WILL EXIST AS  
FAR NORTH AS OH AND PA, WITH MORE ROBUST MOISTURE INTO TX WITH UPPER  
60S F DEWPOINTS.  
   
..UPPER OHIO VALLEY/APPALACHIANS  
 
A REMNANT LINE OF SHOWERS AND THUNDERSTORMS IS EXPECTED TO PERSIST  
NEAR THE COLD FRONT THIS MORNING AS IT MOVES ACROSS THE OH VALLEY  
AND TOWARD THE LOWER GREAT LAKES. DAYTIME HEATING WILL HELP  
DESTABILIZE THE AIR MASS AHEAD OF THIS ACTIVITY, AND STORM  
REJUVENATION IS EXPECTED AFTER 18Z FROM NEAR LAKE ERIE INTO EASTERN  
KY. THESE STORMS WILL MATURE IN THE 21-00Z TIMEFRAME, AFFECTING  
EASTERN OH, WV, AND INTO PA AND POSSIBLY SOUTHWEST NY.  
 
SUBSTANTIAL SOUTHWEST FLOW ALOFT WILL HELP TO PUSH THESE STORMS  
QUICKLY EAST/NORTHEAST ACROSS THE REGION, AND DEEP-LAYER SHEAR MAY  
FAVOR SCATTERED CELLS INITIALLY. MARGINAL HAIL WILL BE POSSIBLE,  
ALONG WITH LOCALLY STRONG GUSTS, ESPECIALLY AS STORM MODE BECOMES  
LINEAR AND PEAK HEATING HAS BEEN ACHIEVED. GIVEN THE NARROW  
INSTABILITY AXIS, STORMS SHOULD WANE AFTER SUNSET.  
   
..SOUTH-CENTRAL TEXAS  
 
SCATTERED SHOWERS AND ELEVATED THUNDERSTORMS ARE EXPECTED THROUGHOUT  
MUCH OF THE DAY AS THE COLD FRONT RAPIDLY UNDERCUTS A MOIST AND  
UNSTABLE AIR MASS. FORECAST SOUNDINGS SHOW MUCAPE PARCELS ROOTED IN  
THE 850-700 MB LAYER, WITH EFFECTIVE DEEP-LAYER SHEAR OF 50-60 KT.  
INITIAL ACTIVITY MAY DEVELOP OVER CENTRAL TX DURING THE MORNING AND  
THROUGH MIDDAY, WITH ADDITIONAL NEW ELEVATED DEVELOPMENT TRANSLATING  
SOUTHWARD AS THE FRONT CONTINUALLY LIFTS THE MOIST AIR MASS. A FEW  
HAIL REPORTS AT OR ABOVE 1.00" WILL BE POSSIBLE.  
 
..JEWELL/MOORE.. 04/18/2026  
 
 
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