430  
ACUS03 KWNS 011935  
SWODY3  
SPC AC 011934  
 
DAY 3 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0234 PM CDT TUE JUL 01 2025  
 
VALID 031200Z - 041200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE  
NORTHERN HIGH PLAINS...UPPER MIDWEST INTO THE GREAT LAKES...AND THE  
NORTHEAST...  
   
..SUMMARY
 
 
SCATTERED STORMS CAPABLE OF LARGE HAIL AND SEVERE WIND GUSTS ARE  
FORECAST ACROSS THE NORTHEAST ON THURSDAY. ISOLATED SEVERE WIND  
GUSTS ARE ALSO POSSIBLE IN THE NORTHERN PLAINS AND PARTS OF THE  
UPPER MIDWEST INTO THE GREAT LAKES.  
   
..SYNOPSIS
 
 
A MID-LEVEL TROUGH WILL DEEPEN OVER NEW ENGLAND AS AN UPPER TROUGH  
MOVES OVER THE MIDWEST, AND BROAD MID-LEVEL TROUGHING WITH MULTIPLE  
EMBEDDED IMPULSES, OVERSPREADS THE U.S. WEST OF THE ROCKIES ON  
THURSDAY. THE EAST AND WEST COAST UPPER TROUGHS WILL ENCOURAGE  
SURFACE TROUGHING ACROSS THE NORTHEAST AND THE PLAINS STATES, AS  
WELL AS WEAK SURFACE LOW DEVELOPMENT OVER THE GREAT BASIN. GIVEN THE  
PRESENCE OF SEASONAL LOW-LEVEL MOISTURE, AND EXPECTED DIURNAL  
HEATING, AT LEAST SCATTERED THUNDERSTORMS WILL DEVELOP ACROSS MUCH  
OF THE INTERIOR WEST, INTO THE PLAINS, MIDWEST, AND EAST COAST  
REGIONS. AT LEAST ISOLATED STRONG TO POTENTIALLY SEVERE STORMS COULD  
DEVELOP OVER PARTS OF THE NORTHERN CONUS, WHERE APPRECIABLE VERTICAL  
WIND SHEAR WILL OVERSPREAD THE WARM, MOIST AIRMASS TO SUPPORT  
ORGANIZED THUNDERSTORMS.  
   
..NORTHEAST
 
 
AS THE SURFACE TROUGH PROGRESSES ACROSS THE NORTHEAST, DEEP-LAYER  
NORTHWESTERLY FLOW WILL OVERSPREAD THE REGION. DIURNAL HEATING OF A  
SEASONABLY MOIST BOUNDARY LAYER WILL FOSTER MODEST BUOYANCY, WITH  
500-1500 J/KG MLCAPE EXPECTED. AS THUNDERSTORMS DEVELOP DURING THE  
AFTERNOON, THEY WILL ENCOUNTER ROUGHLY 25-35 KTS OF EFFECTIVE BULK  
SHEAR, CHARACTERIZED BY ELONGATED/STRAIGHT HODOGRAPHS. MULTICELLS  
AND SHORT LINE SEGMENTS SHOULD BE THE MAIN STORM MODES, WITH  
ISOLATED DAMAGING GUSTS THE PRIMARY THREAT WITH THE STRONGER STORMS.  
 
   
..UPPER MIDWEST INTO THE GREAT LAKES
 
 
A BELT OF 35-45 KT NORTHWESTERLY FLOW ON THE BACK SIDE OF THE EAST  
COAST UPPER TROUGH WILL OVERSPREAD THE GREAT LAKES DURING THE  
AFTERNOON HOURS, WHERE DIURNAL HEATING OF A MOIST LOW-LEVEL AIRMASS  
WILL DESTABILIZE THE BOUNDARY LAYER. MLCAPE MAY EXCEED 2000 J/KG IN  
SPOTS (LOCALLY HIGHER TO 3000 J/KG TOWARD SOUTHEAST MN GIVEN 7.5+  
C/KM MID-LEVEL LAPSE RATES FARTHER TO THE WEST). FORECAST SOUNDINGS  
DEPICT MODESTLY CURVED AND ELONGATED HODOGRAPHS, SUPPORTING  
MULTICELLS AND PERHAPS SUPERCELLS WITH SOME OF THE STRONGER STORMS.  
ISOLATED SEVERE WIND AND HAIL MAY ACCOMPANY THE STRONGER STORMS.  
GREATER SEVERE PROBABILITIES MAY BE NEEDED IN FUTURE OUTLOOKS IF  
FAVORABLE TRENDS IN GREATER STORM COVERAGE ARE REALIZED IN LATER  
AVAILABLE GUIDANCE.  
   
..NORTHERN HIGH PLAINS
 
 
A MID-LEVEL IMPULSE WILL TRAVERSE THE BROADER WESTERN UPPER  
TROUGHING REGIME AND EJECT INTO THE NORTHERN HIGH PLAINS THURSDAY  
AFTERNOON. BY THIS TIME, STEEP MID-LEVEL LAPSE RATES WILL OVERSPREAD  
UPPER 60S F DEWPOINTS TO PROMOTE MODERATE TO LOCALLY STRONG  
INSTABILITY, WITH MLCAPE EXCEEDING 3000 J/KG. MODEST TURNING AND  
STRENGTHENING OF THE WINDS WITH HEIGHT WILL SUPPORT ELONGATED  
HODOGRAPHS WITH SLIGHT LOW-LEVEL CURVATURE, WHICH WILL SUPPORT  
MULTICELLS AND SPLITTING SUPERCELLS GIVEN THE AFOREMENTIONED  
BUOYANCY. THE STORMS ARE FORECAST TO BE ISOLATED IN COVERAGE, WITH A  
FEW INSTANCES OF SEVERE WIND AND HAIL EXPECTED.  
 
..SQUITIERI.. 07/01/2025  
 

 
 
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