357  
ACUS01 KWNS 171622  
SWODY1  
SPC AC 171621  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1021 AM CST MON NOV 17 2025  
 
VALID 171630Z - 181200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM CENTRAL AND  
SOUTHERN MISSOURI INTO FAR WEST-CENTRAL ILLINOIS...  
   
..SUMMARY
 
 
SCATTERED THUNDERSTORMS SHOULD OCCUR THIS EVENING AND OVERNIGHT  
ACROSS PARTS OF THE NORTHERN/CENTRAL PLAINS INTO THE OZARKS AND MID  
MISSISSIPPI VALLEY. ISOLATED THUNDERSTORMS ARE ALSO POSSIBLE ACROSS  
THE SOUTHWEST AND CENTRAL CALIFORNIA. A FEW STRONG THUNDERSTORMS  
CAPABLE OF PRODUCING HAIL MAY OCCUR ACROSS PARTS OF MISSOURI AND  
WESTERN ILLINOIS LATE TONIGHT.  
   
..OZARKS INTO THE MID MISSISSIPPI VALLEY
 
 
SHORTWAVE TROUGH CURRENTLY MOVING ACROSS THE CENTRAL ROCKIES WILL  
CONTINUE EASTWARD ACROSS THE CENTRAL PLAINS, REACHING THE MID MS  
VALLEY BY EARLY TOMORROW. MASS RESPONSE AHEAD OF THIS WAVE WILL  
SUPPORT CONTINUED LOW-LEVEL MOISTURE ADVECTION, WITH LOW 60S  
DEWPOINTS LIKELY REACHING FAR SOUTHEAST KS/FAR SOUTHWEST MO BY EARLY  
TOMORROW MORNING. MID 60S DEWPOINTS WILL LIKELY COVER MUCH OF  
EASTERN OK AND WESTERN AR. THE STRONGER LARGE-SCALE ASCENT WILL  
REMAIN DISPLACED WEST AND NORTH OF THE BETTER LOW-LEVEL MOISTURE,  
AND STRONG CONVECTIVE INHIBITION WILL PRECLUDE SURFACE-BASED STORMS  
THROUGHOUT THE PERIOD. HOWEVER, PERSISTENT THETA-E ADVECTION  
THROUGHOUT THE WARM CONVEYOR WILL PROMOTE ELEVATED BUOYANCY AND THE  
POTENTIAL FOR MULTIPLE ROUNDS OF ELEVATED THUNDERSTORMS FROM THE  
OZARKS NORTHEASTWARD INTO THE MID MS VALLEY.  
 
THE INITIAL ROUND OF DEEPER CONVECTION IS EXPECTED ACROSS THE  
CENTRAL MO VICINITY THIS AFTERNOON NEAR THE TERMINUS OF A 35-40 KT  
LOW-LEVEL JET. BUOYANCY WILL REMAIN MODEST, BUT THERE IS ENOUGH  
SHEAR WITHIN THE CLOUD-BEARING LAYER FOR UPDRAFT ROTATION AND THE  
PRODUCTION OF ISOLATED HAIL. CONTINUED WARM-AIR ADVECTION WILL  
RESULT IN FURTHER LOW-LEVEL WARMING AND MOISTENING, INCREASING THE  
ELEVATED BUOYANCY TONIGHT. THIS BUOYANCY COUPLED WITH GLANCING  
LARGE-SCALE ASCENT AND A STRENGTHENING LOW-LEVEL JET COULD RESULT IN  
ADDITIONAL THUNDERSTORMS FARTHER SOUTH AND WEST INTO SOUTHWEST MO,  
AS WELL AS INCREASED COVERAGE AND INTENSITY OF ANY ONGOING  
THUNDERSTORMS FROM CENTRAL MO INTO FAR WEST-CENTRAL IL. MODERATE TO  
STRONG VERTICAL SHEAR WILL CONTINUE TO SUPPORT ROTATION WITHIN ANY  
DEEP AND PERSISTENT UPDRAFTS, WITH AN ATTENDANT THREAT FOR ISOLATED  
HAIL.  
   
..CA INTO THE SOUTHWEST
 
 
UPPER LOW CURRENTLY OFF THE NORTHERN CA COAST WILL CONTINUE  
SOUTHWARD THROUGHOUT THE DAY, ENDING THE PERIOD OVER THE SAN LUIS  
OBISPO/SANTA BARBARA/VENTURA COUNTY VICINITY. SPORADIC THUNDERSTORMS  
ARE POSSIBLE NEAR THIS UPPER LOW, WHERE COLD MID-LEVEL TEMPERATURE  
AND STRONG FORCING FOR ASCENT ARE ANTICIPATED. A  
NON-LIGHTNING-PRODUCING BAND WILL MOVE THROUGH THE SOUTHERN CA  
COASTAL COUNTIES AHEAD OF THIS LOW. ISOLATED LIGHTNING FLASHES ARE  
ALSO POSSIBLE FARTHER EAST WITHIN THE WARM CONVEYOR OVER THE LOWER  
CO RIVER VALLEY AND WESTERN AZ. MEAGER INSTABILITY SHOULD LIMIT THE  
THREAT FOR ORGANIZED SEVERE THUNDERSTORMS ACROSS THE ENTIRE REGION.  
 
..MOSIER/THORNTON.. 11/17/2025  
 

 
 
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