185  
ACUS02 KWNS 030554  
SWODY2  
SPC AC 030553  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1253 AM CDT WED SEP 03 2025  
 
VALID 041200Z - 051200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN  
TENNESSEE NORTHWARD INTO NORTHERN NEW YORK...  
   
..SUMMARY
 
 
SCATTERED STRONG THUNDERSTORMS MAY IMPACT A CORRIDOR FROM EAST  
TENNESSEE NORTHWARD TO THE US-CANADIAN BORDER ACROSS NORTHERN NEW  
YORK ON THURSDAY, ACCOMPANIED BY A RISK FOR POTENTIALLY DAMAGING  
WIND GUSTS.  
   
.. SYNOPSIS
 
 
A HIGHLY AMPLIFIED MIDLEVEL PATTERN WILL CONTINUE THROUGH  
THURSDAY/DAY-2 AS A LARGE RIDGE PUSHES NORTH THROUGH WESTERN CANADA  
AND A DOWNSTREAM TROUGH PERSISTS ACROSS MUCH OF THE EASTERN UNITED  
STATES. WITHIN THIS AMPLIFIED PATTERN, A SEASONABLY COLD MIDLEVEL  
LOW WILL EXIST ACROSS ONTARIO, WITH MULTIPLE LOBES OF VORTICITY  
ROTATING AROUND THE LOW. ONE SUCH VORTICITY LOBE/SHORTWAVE TROUGH  
WILL MOVE EAST ACROSS THE GREAT LAKES BRINGING WITH IT INCREASING  
ASCENT ACROSS PORTIONS OF THE EASTERN US.  
 
AT THE SURFACE, A COLD FRONT ASSOCIATED WITH THE MIDLEVEL SHORTWAVE  
TROUGH WILL STRETCH THROUGH THE PLAINS EAST-NORTHEAST INTO THE LOWER  
GREAT LAKES AT THE START OF THE FORECAST PERIOD. THIS COLD FRONT  
WILL MAKE SLOW PROGRESS SOUTHWARD ACROSS THE PLAINS AND FASTER  
PROGRESS EAST ACROSS THE EASTERN GREAT LAKES REGION.  
   
.. EAST TENNESSEE NORTHWARD INTO UPSTATE NEW YORK
 
 
SEASONABLE MOISTURE WILL BE IN PLACE ACROSS THE REGION AHEAD OF THE  
ADVANCING SURFACE COLD FRONT. DIURNAL HEATING OF THIS AIRMASS SHOULD  
RESULT IN POCKETS OF MOST-UNSTABLE CAPE UP TO 1500 J/KG TO DEVELOP  
BY EARLY AFTERNOON ACROSS SOUTHERN PORTIONS OF THE REGION TO PERHAPS  
750 J/KG ACROSS NORTHERN PORTIONS OF THE AREA.  
 
THUNDERSTORMS, OR THEIR REMNANTS, ONGOING ACROSS PORTIONS OF EASTERN  
OHIO AND WESTERN PENNSYLVANIA AT THE START OF THE PERIOD, SHOULD  
WEAKEN/DISSIPATE THROUGH THE MORNING AS THEY MOVE EAST. THESE  
SHOWERS/STORMS OR THEIR OUTFLOW MAY PROVIDE POTENTIAL FOCI FOR  
THUNDERSTORM DEVELOPMENT/INTENSIFICATION DURING THE AFTERNOON. TO  
THE WEST, INCREASING LARGE SCALE ASCENT ASSOCIATED WITH THE  
SHORTWAVE TROUGH AND LOW-LEVEL CONVERGENCE ALONG THE SURFACE COLD  
FRONT SHOULD SUPPORT ADDITIONAL BANDS OF THUNDERSTORMS.  
 
THE BEST THERMODYNAMICS WILL RESIDE ACROSS TENNESSEE AND ADJACENT  
AREAS, WITH THE BEST DEEP-LAYER SHEAR DISPLACED TO THE NORTH ACROSS  
NORTHERN PENNSYLVANIA AND NEW YORK. HOWEVER, THE JOINT DISTRIBUTION  
OF FORECAST PROFILES OF SHEAR AND BUOYANCY SHOULD FAVOR THUNDERSTORM  
ORGANIZATION INTO SMALL MULTICELL CLUSTERS OR SMALL LINEAR SEGMENTS,  
WITH THE STRONGEST OF THESE CAPABLE OF SOME DAMAGING WIND POTENTIAL.  
 
..MARSH.. 09/03/2025  
 

 
 
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