466  
ACUS02 KWNS 041727  
SWODY2  
SPC AC 041726  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1226 PM CDT THU SEP 04 2025  
 
VALID 051200Z - 061200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE  
OHIO AND TENNESSEE VALLEYS INTO THE CENTRAL APPALACHIANS...  
   
..SUMMARY  
 
SCATTERED THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WIND GUSTS AND  
ISOLATED LARGE HAIL ARE EXPECTED ACROSS PARTS OF THE OHIO AND  
TENNESSEE VALLEYS INTO THE CENTRAL APPALACHIANS ON FRIDAY.  
   
..SYNOPSIS  
 
A DEEP/VERTICALLY STACKED CYCLONE WILL MOVE GRADUALLY NORTHWARD  
ACROSS ONTARIO TOWARD HUDSON BAY THROUGH THE PERIOD, AS AN  
ACCOMPANYING MIDLEVEL JET STREAK ADVANCES FROM THE GREAT LAKES INTO  
QUEBEC. PERIPHERAL TO THE DEEP CYCLONE, BROAD MIDLEVEL TROUGHING  
WILL PERSIST ACROSS MUCH OF THE EASTERN CONUS. AN ACCOMPANYING COLD  
FRONT WILL EXTEND FROM THE GREAT LAKES REGION SOUTHWESTWARD ACROSS  
THE OH VALLEY INTO THE SOUTHERN PLAINS. GIVEN THE SLOWLY  
EVOLVING/AMPLIFIED UPPER-LEVEL PATTERN, THE COLD FRONT WILL ONLY  
MOVE GRADUALLY EAST-SOUTHEASTWARD THROUGH THE PERIOD.  
   
..OHIO/TENNESSEE VALLEYS INTO THE CENTRAL APPALACHIANS  
 
AHEAD OF THE COLD FRONT, AMPLE DIURNAL HEATING AMID UPPER 60S  
DEWPOINTS WILL CONTRIBUTE TO A MODERATELY UNSTABLE (AROUND 2500 J/KG  
MLCAPE), UNCAPPED PRE-CONVECTIVE AIR MASS. POTENTIALLY AIDED BY A  
CONVECTIVELY AUGMENTED MIDLEVEL IMPULSE APPROACHING THE OH VALLEY  
FROM THE WEST, SCATTERED THUNDERSTORMS SHOULD DEVELOP  
ALONG/IMMEDIATELY AHEAD OF THE FRONT DURING THE AFTERNOON INTO  
EVENING/OVERNIGHT. THE AFOREMENTIONED BUOYANCY AND AROUND 30-40 KT  
OF EFFECTIVE SHEAR SHOULD PROMOTE CONVECTIVE ORGANIZATION INTO  
CLUSTERS/SMALL LINE SEGMENTS AND PERHAPS TRANSIENT SUPERCELL  
STRUCTURES. THE STRONGER/LONGER-LIVED STORMS WILL BE CAPABLE OF  
PRODUCING DAMAGING WIND GUSTS AND ISOLATED SEVERE HAIL. THE BEST  
OVERLAP OF MODERATE BUOYANCY (HIGHER WITH SOUTHWARD EXTENT) AND  
FAVORABLE DEEP-LAYER SHEAR (STRONGER WITH NORTHWARD EXTENT) SHOULD  
EXIST OVER KY AND SURROUNDING STATES, WHERE A SLIGHT RISK WAS ADDED.  
   
..MID-SOUTH INTO THE SOUTHERN PLAINS  
 
THE COLD FRONT WILL BE ORIENTED MORE WEST-EAST OVER THIS REGION,  
WITH THE STRONGER DEEP SHEAR CONFINED TO THE COOL SIDE OF THE  
BOUNDARY. ADDITIONALLY, CONVECTIVE INITIATION MAY OCCUR LATER INTO  
THE EVENING/OVERNIGHT HOURS ALONG THE SHARPENING COLD FRONT.  
NEVERTHELESS, MODERATE-STRONG BUOYANCY AIDED BY STEEP DEEP-LAYER  
LAPSE RATES WILL PROMOTE STRONG STORMS CAPABLE OF PRODUCING LOCALLY  
DAMAGING GUSTS AND SPORADIC, MARGINALLY SEVERE HAIL.  
 
..WEINMAN.. 09/04/2025  
 
 
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