365  
ACUS02 KWNS 170531  
SWODY2  
SPC AC 170530  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1230 AM CDT THU JUL 17 2025  
 
VALID 181200Z - 191200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS  
OF NEBRASKA...SOUTH DAKOTA...AND SOUTHERN MINNESOTA INTO IOWA...AND  
ACROSS PORTIONS OF THE SOUTHERN MID-ATLANTIC...  
   
..SUMMARY  
 
STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS PORTIONS OF SOUTH  
DAKOTA AND NEBRASKA INTO SOUTHERN MINNESOTA AND IOWA. ADDITIONAL  
STRONG TO SEVERE STORMS MAY OCCUR ACROSS PORTIONS OF WEST VIRGINIA,  
VIRGINIA AND NORTH CAROLINA.  
   
..NE/SD/MN/IA  
 
STRONGER MID/UPPER LEVEL WESTERLY FLOW WILL REMAIN CONFINED TO THE  
NORTHERN TIER OF THE U.S. FROM THE NORTHERN PLAINS TO NEW ENGLAND.  
SHORTWAVE IMPULSES WILL MIGRATE THROUGH THE WESTERLY FLOW, BUT  
STRONGER INSTABILITY WILL REMAIN DISPLACED TO THE SOUTH OF THE BELT  
OF STRONGER FLOW. NEVERTHELESS, A WEAK SURFACE LOW AND ATTENDANT  
TROUGH IS FORECAST TO DEVELOP OVER THE NORTHERN/CENTRAL HIGH PLAINS,  
AND A STALLED FRONT WILL GRADUALLY LIFT NORTH ACROSS THE NORTHERN  
PLAINS AND PORTIONS OF THE MIDWEST. RICH BOUNDARY LAYER MOISTURE AND  
A PLUME OF STEEP MIDLEVEL LAPSE RATES WILL SUPPORT STRONG  
DESTABILIZATION ACROSS PARTS OF KS/NE/SD AND THE MID-MO VALLEY.  
 
VERTICALLY VEERING WIND PROFILES WILL SUPPORT ROTATING STORMS, WHILE  
ELONGATED/STRAIGHT HODOGRAPHS ABOVE 2-3 KM APPEAR FAVORABLE FOR  
HAIL. STEEP LOW-LEVEL LAPSE RATES, AND SOME MODEST DRY AIR NOTED  
BETWEEN 700-500 MB SUGGEST DAMAGING WIND POTENTIAL IS ALSO POSSIBLE.  
WHILE SOME MODEST LOW-LEVEL HODOGRAPH CURVATURE IS NOTED, 0-1 KM  
SHEAR IS EXPECTED TO REMAIN MODEST, THOUGH A TORNADO OR TWO CANNOT  
BE RULED OUT.  
 
WHILE THIS ENVIRONMENT GENERALLY APPEARS FAVORABLE FOR AT LEAST  
ISOLATED SUPERCELLS, CONVECTIVE EVOLUTION IS UNCERTAIN GIVEN  
SOMEWHAT SUBTLE FORCING. ADDITIONALLY, FORECAST HEIGHT TENDENCIES  
ARE NEUTRAL TO POSSIBLY SMALL HEIGHT RISES AS A SHORTWAVE UPPER  
RIDGE BUILDS OVER THE MT/WY AFTER 21Z. CAPPING ACROSS PORTIONS OF  
THE REGION COULD LIMIT COVERAGE. WHERE CAPPING IS NOT AN ISSUE,  
STRONG INSTABILITY AND MODEST SHEAR COULD RESULT IN RAPID  
CLUSTERING. FURTHERMORE, EARLY CONVECTION MAY BE ONGOING ACROSS  
PARTS OF ND/SD INTO MN. HOW THESE STORMS AND ASSOCIATED CLOUDINESS  
EVOLVE THROUGH THE MORNING, AND ANY POTENTIAL OUTFLOW GENERATED BY  
THIS CONVECTION ALSO RESULT IN UNCERTAINTY. GIVEN THESE  
UNCERTAINTIES, DESPITE A FAVORABLE AIRMASS, WILL MAINTAIN MARGINAL  
(LEVEL 1 OF 5) PROBABILITIES WITH SOME EXPANSION OF THE AREA.  
OUTLOOK UPGRADES MAY BE NECESSARY LATER IF SOME OF THE  
AFOREMENTIONED UNCERTAINTIES ARE RESOLVED.  
   
..SOUTHERN MID-ATLANTIC VICINITY  
 
A WEAK SHORTWAVE IMPULSE IS FORECAST TO MIGRATE ACROSS THE BLUE  
RIDGE TO THE MID-ATLANTIC COAST IN MODEST WESTERLY FLOW ON THE  
NORTHERN PERIPHERY OF THE UPPER HIGH. A VERY MOIST AIRMASS WILL  
SUPPORT MODERATE DESTABILIZATION. WHILE SHEAR WILL REMAIN MODEST,  
MULTICELL CLUSTERS COULD PRODUCE STRONG DOWNBURSTS. IF STORMS CAN  
ORGANIZE ALONG CONSOLIDATING OUTFLOWS, INCREASING POTENTIAL FOR  
DAMAGING WINDS WILL OCCUR.  
 
..LEITMAN.. 07/17/2025  
 
 
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