623  
ACUS02 KWNS 051733  
SWODY2  
SPC AC 051732  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1232 PM CDT FRI SEP 05 2025  
 
VALID 061200Z - 071200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN  
PENNSYLVANIA AND NEW JERSEY NORTHEASTWARD INTO FAR SOUTHERN MAINE...  
   
..SUMMARY  
 
SCATTERED STRONG TO SEVERE THUNDERSTORMS ARE MOST LIKELY SATURDAY  
FROM EASTERN PENNSYLVANIA AND NEW JERSEY INTO PARTS OF SOUTHERN NEW  
ENGLAND. ISOLATED STRONG GUSTS ARE POSSIBLE EXTENDING SOUTHWARD  
ACROSS THE PIEDMONT.  
   
..SYNOPSIS  
 
A LEADING MID/UPPER LEVEL SPEED MAX WILL PIVOT NORTHEASTWARD ACROSS  
QUEBEC ON SATURDAY, WITH THE RIGHT-ENTRANCE REGION SWEEPING ACROSS  
MUCH OF THE NORTHEASTERN STATES. GIVEN THE TRAJECTORY, ONLY SUBTLE  
HEIGHT FALLS WILL OCCUR OVER THE REGION, BUT MIDLEVEL SOUTHWEST  
WINDS WILL INCREASE TO AROUND 60 KT, ENHANCING DEEP-LAYER SHEAR.  
 
THIS CYCLONIC PATTERN ALOFT WILL EXTEND WELL SOUTH ACROSS THE  
APPALACHIANS, WHERE WINDS WILL BE MUCH WEAKER. HOWEVER, RELATIVELY  
COOL MIDLEVEL TEMPERATURES WILL AID DESTABILIZATION IN THESE AREAS.  
 
AT THE SURFACE, A COLD FRONT WILL PUSH EAST FROM ME INTO NORTHERN  
VA, WITH A MOIST AIR MASS AHEAD OF IT. WINDS AT 850 MB WILL INCREASE  
TO 30-40 KT ACROSS THE NORTHEAST, WHICH WILL AID THE NORTHWARD  
TRANSPORT OF MOISTURE AND DESTABILIZATION.  
   
..NORTHEAST  
 
A WAVE OF LOW PRESSURE IS FORECAST TO DEVELOP OVER EASTERN PA EARLY  
IN THE DAY, TRANSLATING NORTHEASTWARD ALONG THE FRONT AND INTO ME BY  
LATE AFTERNOON. STRONGER HEATING AND STEEP LOW-LEVEL LAPSE RATES  
SHOULD DEVELOP FROM VA INTO EASTERN PA/NJ AND INTO INTERIOR SOUTHERN  
NEW ENGLAND, WITH MLCAPE AROUND 1500 J/KG AS AN AREAL AVERAGE.  
 
AS THE WARM AIR MASS DEVELOPS AND ACCELERATES NORTH AHEAD OF THE  
COLD FRONT, BOTH INSTABILITY AND SHEAR PARAMETER SPACE WILL BECOME  
FAVORABLE FOR SEVERE STORMS, INCLUDING SUPERCELL POTENTIAL. A LINE  
OF STORMS IS EXPECTED BY 17 TO 18Z, FROM EASTERN PA TOWARD THE  
HUDSON VALLEY, EXPANDING N/S AND PUSHING EAST THROUGH THE AFTERNOON.  
GIVEN 40-50 KT EFFECTIVE DEEP-LAYER SHEAR AND ENHANCED LOW-LEVEL  
SHEAR WITH THE MIDDAY SURFACE THETA-E SURGE, THE INITIAL STORM MODE  
MAY BE CELLULAR ALONG THE BOUNDARY, WITH A BRIEF TORNADO OR TWO  
POSSIBLE ALONG WITH SOME HAIL. DAMAGING WINDS ARE THEN MOST LIKELY  
AS OUTFLOWS MERGE, AND SPREAD EAST ACROSS THE REMAINDER OF THE  
REGION THROUGH LATE AFTERNOON.  
   
..PIEDMONT  
 
STRONG HEATING WILL OCCUR ACROSS MOST OF THE AREA, WITH AREAS OF  
HIGH-LEVEL CLOUDS EXPECTED ACROSS THE APPALACHIANS. THE  
MOIST/UNCAPPED AIR MASS AND WEAK SURFACE TROUGH SHOULD YIELD  
SCATTERED AFTERNOON STORMS. DESPITE WEAK SHEAR, FAVORABLE TIMING  
WITH PEAK HEATING/STEEP BOUNDARY LAYER LAPSE RATES AS WELL AS UP TO  
2000 J/KG MUCAPE MAY YIELD LOCALLY STRONG TO DAMAGING DOWNBURSTS. A  
FEW STORMS COULD PRODUCE MARGINAL HAIL GIVEN SUFFICIENT LONGEVITY.  
 
..JEWELL.. 09/05/2025  
 
 
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