652  
ACUS01 KWNS 011606  
SWODY1  
SPC AC 011604  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1104 AM CDT TUE JUL 01 2025  
 
VALID 011630Z - 021200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE  
MID-ATLANTIC REGION AND ACROSS WESTERN PORTIONS OF NEBRASKA AND  
SOUTH DAKOTA...  
   
..SUMMARY  
 
SCATTERED STRONG TO SEVERE STORMS ARE POSSIBLE ACROSS PARTS OF THE  
MID-ATLANTIC INTO THE NORTHEAST THIS AFTERNOON/EVENING. A FEW  
SEVERE THUNDERSTORMS ARE POSSIBLE OVER WESTERN PARTS OF NEBRASKA AND  
SOUTH DAKOTA.  
   
..MID-ATLANTIC INTO THE NORTHEAST  
 
RECENT SATELLITE IMAGERY SHOWS A WELL-DEFINED SHORTWAVE TROUGH  
EXTENDING FROM WESTERN QC THROUGH THE MIDDLE OH VALLEY INTO THE MID  
MS VALLEY. REGIONAL RADAR IMAGERY DEPICTS SHOWERS AND THUNDERSTORMS  
PRECEDING THIS WAVE FROM ACROSS THE MID/UPPER OH VALLEY, WITH THE  
STRONGER STORMS OCCURRING ALONG AN ASSOCIATED COLD FRONT THAT  
EXTENDS FROM FAR WESTERN NY SOUTHWESTWARD ACROSS WESTERN PA AND  
ALONG THE WV/OH BORDER THROUGH EASTERN KY.  
 
THE GENERAL EXPECTATION THROUGHOUT THE DAY IS FOR THIS SHORTWAVE  
TROUGH AND ASSOCIATED COLD FRONT TO PROGRESS EASTWARD INTO THE  
INCREASINGLY MOIST AND UNSTABLE AIRMASS DOWNSTREAM, PROMOTING  
WIDESPREAD THUNDERSTORM DEVELOPMENT THIS AFTERNOON. MODERATE  
MID-LEVEL FLOW EXTENDS THROUGH THE EASTERN PERIPHERY OF THIS WAVE,  
WITH THE STRONGEST FLOW (I.E. AROUND 40 KT AT 500 MB) EXPECTED TO  
MOVE ACROSS NY AND NEW ENGLAND. GIVEN THE MORE NORTHERN TRAJECTORY  
OF THE STRONGER FLOW, THERE WILL BE LIMITED OVERLAP BETWEEN THE  
STRONGEST FLOW AND THE BETTER BUOYANCY, WHICH WILL REMAIN FARTHER  
SOUTH ACROSS THE MID-ATLANTIC. EVEN SO, THE OVERALL ENVIRONMENT WILL  
SUPPORT SOME ORGANIZATION OF STORMS INTO LINE SEGMENTS/CLUSTERS.  
SCATTERED THUNDERSTORMS WILL INCREASE IN COVERAGE WITH TIME AND  
NUMEROUS THUNDERSTORMS ARE EXPECTED BY MID-LATE AFTERNOON WHILE  
MOVING EAST FROM PA/WV IN NJ/VA/MD. RECENTLY ISSUED MCD #1529 ALSO  
ADDRESSES THE SEVERE POTENTIAL IN THIS REGION. MORE LIMITED STORM  
COVERAGE IS ANTICIPATED FARTHER NORTH. STRONG TO SEVERE GUSTS (50-65  
MPH) ARE POSSIBLE WITH THE STRONGER DOWNDRAFTS.  
   
..BLACK HILLS/SD INTO THE CENTRAL HIGH PLAINS  
 
A WEAK SHORTWAVE TROUGH IS CURRENTLY PROGRESSING THROUGH EASTERN MT  
AND EASTERN WY, THROUGHOUT THE NORTHERN PERIPHERY OF THE UPPER  
RIDGING THAT EXTENDS FROM THE SOUTHERN PLAINS THROUGH THE NORTHERN  
ROCKIES. THIS WAVE IS FORECAST TO CONTINUE EASTWARD/SOUTHEASTWARD,  
EVENTUALLY INTERACTING WITH THE MODERATE LOW-LEVEL MOISTURE EXPECTED  
TO ADVECT NORTHWARD ACROSS WESTERN PORTIONS OF KS, NE AND SD. ASCENT  
ATTENDANT TO THIS WAVE WILL AUGMENT LOW-LEVEL CONVERGENCE NEAR AN  
ASSOCIATED SURFACE LOW TO FOSTER AFTERNOON THUNDERSTORM DEVELOPMENT.  
LOW-LEVEL SOUTHERLY FLOW VEERING TO NORTHWESTERLY ALOFT WILL FOSTER  
MODERATE EFFECTIVE SHEAR (I.E. 30 TO 40 KT) AND THE POTENTIAL FOR A  
COUPLE OF SUPERCELLS. LARGE HAIL WILL BE THE PRIMARY RISK WITH THESE  
STORMS.  
 
SOME ADDITIONAL THUNDERSTORMS ARE POSSIBLE LATER TONIGHT ACROSS FAR  
SOUTHERN ND AND CENTRAL/EASTERN SD AS A STRENGTHENING LOW-LEVEL JET  
CONTRIBUTES TO WARM-AIR ADVECTION ACROSS A DEVELOPING WARM FRONTAL  
ZONE. MODERATE SHEAR AND STEEP MID-LEVEL LAPSE RATES WILL SUPPORT A  
FEW STRONGER STORMS CAPABLE OF PRODUCING ISOLATED LARGE HAIL.  
   
..CENTRAL APPALACHIANS INTO THE SOUTHEAST  
 
AFTERNOON THUNDERSTORMS ARE EXPECTED ACROSS A LARGE AREA FROM THE  
CENTRAL APPALACHIANS AND CAROLINAS SOUTHWESTWARD INTO THE SOUTHEAST,  
ALONG OR JUST AHEAD OF A WEAK, EASTWARD-PROGRESSING COLD FRONT.  
LIMITED VERTICAL SHEAR SHOULD PROMOTE LESS ORGANIZED STORMS,  
ALTHOUGH A FEW STRONG, WATER-LOADED DOWNDRAFTS CAPABLE OF PRODUCING  
DAMAGING WINDS ARE POSSIBLE.  
 
..MOSIER/KARSTENS.. 07/01/2025  
 
 
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