303  
ACUS01 KWNS 021951  
SWODY1  
SPC AC 021949  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0249 PM CDT SUN AUG 02 2026  
 
VALID 022000Z - 031200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE EAST  
AS WELL AS PARTS OF THE SOUTHWEST AND NORTHERN PLAINS...  
   
..SUMMARY  
 
SCATTERED STRONG TO LOCALLY SEVERE THUNDERSTORM DEVELOPMENT IS  
EXPECTED THIS AFTERNOON AND EVENING ACROSS PARTS OF THE LOWER GREAT  
LAKES AND UPPER OHIO VALLEY INTO THE MIDDLE AND SOUTHERN ATLANTIC  
PIEDMONT. DAMAGING WINDS ARE THE PRIMARY HAZARD, ALTHOUGH A TORNADO  
COULD OCCUR.  
   
..20Z UPDATE  
 
ONLY MINOR CHANGES WERE MADE WITH THIS UPDATE. THE MRGL RISK WAS  
EXPANDED SLIGHTLY EASTWARD IN PORTIONS OF EASTERN SC, WHERE AN  
ONGOING CLUSTER OF THUNDERSTORMS WILL CONTINUE TO POSE A RISK OF  
DAMAGING WIND GUSTS, GIVEN A VERY WARM/MOIST DOWNSTREAM AIR MASS.  
FARTHER NORTH, THE MRGL RISK WAS EXPANDED INTO PARTS OF NORTHERN NJ  
AND NORTHEAST PA. CLOUDS BREAKS HAVE SUPPORTED MODEST  
DESTABILIZATION OF A MOIST AIR MASS, AND HIGH-RESOLUTION GUIDANCE  
DEPICTS THUNDERSTORMS MOVING INTO THE AREA TONIGHT -- FOCUSED ALONG  
A NORTHWARD-MOVING WARM FRONT. DESPITE MODEST INSTABILITY, ENHANCED  
LOW-LEVEL FLOW/SHEAR OVERSPREADING THE REGION IN TANDEM WITH THE  
WARM FRONT COULD SUPPORT A COUPLE LOOSELY ORGANIZED CELLS/CLUSTERS  
WITH AN ACCOMPANYING RISK OF DAMAGING WIND GUSTS AND PERHAPS A BRIEF  
TORNADO. ELSEWHERE, THE FORECAST REMAINS ON TRACK AND NO CHANGES  
WERE NEEDED.  
 
..WEINMAN.. 08/02/2026  
   
PREV DISCUSSION  
/ISSUED 1116 AM CDT SUN AUG 02 2026/  
   
..EASTERN STATES  
 
CURRENT SATELLITE IMAGERY SHOWS A POSITIVELY TITLED SHORTWAVE TROUGH  
EXTENDING FROM LOWER MI SOUTHWESTWARD INTO THE MID-SOUTH, WHILE  
RECENT SURFACE ANALYSIS PLACES A CORRIDOR OF LOW PRESSURE ASSOCIATED  
WITH THIS SHORTWAVE FROM THE MIDDLE OH VALLEY INTO THE LOWER GREAT  
LAKES. SEVERAL SURFACE LOWS ARE EMBEDDED WITHIN THIS BROADER AREA OF  
LOW PRESSURE, INCLUDING A PRIMARY LOW OVER NORTH-CENTRAL OH/WESTERN  
LAKE ERIE. A COLD FRONT EXTENDS SOUTHWARD FROM THIS LOW TO THE TN/NC  
BORDER VICINITY BEFORE ARCING BACK MORE SOUTHWESTWARD THROUGH  
CENTRAL AL AND SOUTHERN MS.  
 
THIS SYSTEM (I.E. BOTH THE SHORTWAVE TROUGH AND ASSOCIATED COLD  
FRONT) IS FORECAST TO GRADUALLY PUSH EASTWARD WHILE WEAKENING.  
AIRMASS PRECEDING THIS SYSTEM IS VERY MOIST, EVIDENCED BY UPPER  
60S/LOW 70S DEWPOINTS AND PW VALUES AT OR ABOVE 2 INCHES ON THE  
REGIONAL 12Z SOUNDINGS. WIDESPREAD CLOUD COVER IS IN PLACE, BUT  
AMPLE MOISTURE HAS ALREADY RESULTED IN AIRMASS DESTABILIZATION,  
ALTHOUGH THE OVERALL BUOYANCY WILL REMAIN MUTED BY POOR LAPSE RATES.  
GENERAL EXPECTATION IS FOR THUNDERSTORM COVERAGE TO INCREASE  
SUBSTANTIALLY OVER THE NEXT FEW HOURS, FOSTERED BY A COMBINATION OF  
LOW-LEVEL CONFLUENCE AND MODEST LARGE-SCALE ASCENT.  
 
LOW TO MID-LEVEL FLOW THROUGHOUT THE EASTERN PERIPHERY OF THE  
SHORTWAVE TROUGH IS GENERALLY EXPECTED TO BE MODEST, RANGING FROM  
AROUND 40 KT ACROSS THE ALLEGHENY PLATEAU/UPPER OHIO VALLEY/LOWER  
GREAT LAKES VICINITY TO 20 KT ACROSS GA AND SC. CONSEQUENTLY, A FEW  
MORE ORGANIZED STORMS ARE POSSIBLE ACROSS PORTIONS OF THE ALLEGHENY  
PLATEAU, UPPER OHIO VALLEY, AND LOWER GREAT LAKES, WHILE A LARGELY  
DISORGANIZED MULTICELLULAR MODE IS ANTICIPATED ELSEWHERE.  
WATER-LOADED DOWNBURSTS ARE THE PRIMARY RISK, ALTHOUGH LOW-LEVEL  
SHEAR/SRH IN THE PRESENCE OF A MOIST BOUNDARY LAYER SUGGESTS A BRIEF  
TORNADO IS POSSIBLE WHERE GREATER STORM ORGANIZATION IS  
EXPECTED.  
   
..NORTH DAKOTA/NORTHWEST MINNESOTA  
 
EXPANSIVE UPPER RIDGING EXISTS FROM SOUTHERN CA/WESTERN AZ THROUGH  
THE PLAINS AND INTO MANITOBA AND ONTARIO. A STRONG SHORTWAVE TROUGH  
IS FORECAST TO PROGRESS THROUGH CANADIAN PRAIRIE PROVINCES WITHIN  
THE NORTHERN PERIPHERY OF THIS RIDGING. A COLD FRONT ASSOCIATED WITH  
THIS WAVE IS EXPECTED TO PUSH EASTWARD ACROSS THE DAKOTAS,  
INTERACTING WITH A MOISTENING AIRMASS ACROSS THE REGION. A  
CONDITIONAL RISK FOR SEVERE THUNDERSTORMS EXISTS THIS AFTERNOON, BUT  
MOST OF THE GUIDANCE KEEPS THE AIRMASS CAPPED AND FREE OF DEEP  
CONVECTION. BETTER POTENTIAL FOR THUNDERSTORM DEVELOPMENT IS  
EXPECTED OVERNIGHT AND INTO TOMORROW MORNING AS LARGE-SCALE ASCENT  
ATTENDANT TO THE APPROACHING SHORTWAVE COMBINES WITH WARM-AIR  
ADVECTION TO FOSTER ELEVATED THUNDERSTORM DEVELOPMENT. ISOLATED  
INSTANCES OF HAIL AND A STRONG GUST OR TWO ARE POSSIBLE WITH THESE  
STORMS.  
   
..SOUTHEAST ARIZONA/FAR SOUTHWEST NEW MEXICO  
 
WIDELY SCATTERED THUNDERSTORMS SHOULD DEVELOP OVER THE  
MOUNTAINS/HIGHER TERRAIN OF THE CENTRAL/SOUTHERN ARIZONA/NEW MEXICO  
BORDER VICINITY THIS AFTERNOON. MODERATE EASTERLY/NORTHEASTERLY  
MID-LEVEL FLOW SHOULD FAVOR SOUTHWESTWARD MOTION INTO THE LOWER  
TERRAIN OF SOUTHEAST ARIZONA. MODEST BUOYANCY SHOULD ALLOW FOR STORM  
PERSISTENCE ACROSS SOUTHEAST AZ, INCLUDING THE POTENTIAL FOR  
ISOLATED STRONG TO SEVERE GUSTS.  
 
 
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