050  
ACUS01 KWNS 021630  
SWODY1  
SPC AC 021628  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1128 AM CDT WED SEP 02 2026  
 
VALID 021630Z - 031200Z  
 
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
WESTERN NEW YORK...  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
MONTANA...  
   
..SUMMARY  
 
SCATTERED TO NUMEROUS SEVERE THUNDERSTORMS ARE LIKELY ACROSS PARTS  
OF THE GREAT LAKES TO THE MID-ATLANTIC THIS AFTERNOON THROUGH  
TONIGHT. DAMAGING WINDS ARE THE MAIN THREAT, THOUGH SOME LARGE HAIL  
AND A FEW TORNADOES MAY ALSO OCCUR. SCATTERED SEVERE GUSTS AND  
ISOLATED LARGE HAIL APPEAR POSSIBLE OVER THE NORTHERN ROCKIES/HIGH  
PLAINS THIS AFTERNOON AND EVENING.  
   
..LOWER MICHIGAN INTO THE MID-ATLANTIC  
 
AN ONGOING CLUSTER ACROSS SOUTH-CENTRAL PA HAS A WELL ESTABLISHED  
COLD POOL AND A HISTORY OF PRODUCING DAMAGING WINDS ACROSS  
WESTERN/CENTRAL PA. THIS CONVECTION IS EXPECTED TO CONTINUE MOVING  
QUICKLY SOUTHEASTWARD THROUGH THE AFTERNOON ACROSS PARTS OF  
MD/DC/NORTHERN VA AND VICINITY. THERE IS STILL SOME UNCERTAINTY ON  
WHETHER THIS CLUSTER WILL BE ABLE TO MAINTAIN INTENSITY WITH  
SOUTHWARD EXTENT INTO THE MID-ATLANTIC, AS IT BECOMES INCREASINGLY  
REMOVED FROM THE STRONGER FORCING ALOFT/MID-LEVEL FLOW OVER THE  
GREAT LAKES INTO NY. STILL, A DIFFERENTIAL HEATING ZONE REMAINS  
APPARENT ALONG/NEAR THE CHESAPEAKE BAY PER RECENT VISIBLE SATELLITE  
IMAGERY AND SURFACE OBSERVATIONS. THE CLUSTER SHOULD TEND TO REMAIN  
ON THE WARM SIDE OF THIS BOUNDARY, WITH STEEPENING LOW-LEVEL LAPSE  
RATES DEVELOPING AS DAYTIME HEATING CONTINUES TO DESTABILIZE THE  
DOWNSTREAM AIRMASS. SCATTERED DAMAGING WINDS WILL LIKELY REMAIN A  
THREAT WITH THESE THUNDERSTORMS AS THEY TRACK ACROSS THE SOUTHERN  
MID-ATLANTIC BEFORE EVENTUALLY WEAKENING.  
 
IN THE WAKE OF THIS LATE MORNING/EARLY AFTERNOON ACTIVITY, IT  
APPEARS LIKELY THAT ROBUST DESTABILIZATION WILL OCCUR ACROSS PARTS  
OF LOWER MI INTO WESTERN NY. 12Z OBSERVED SOUNDINGS FROM APX/DTX/BUF  
SHOWED MODERATE TO VERY STRONG MUCAPE AND MODESTLY STEEPENED  
MID-LEVEL LAPSE RATES WITH AN EML. THIS FAVORABLE AIRMASS WILL  
SPREAD EASTWARD THROUGH THE DAY IN TANDEM WITH A MID-LEVEL SHORTWAVE  
TROUGH AND 50-60 KT MID-LEVEL JET ALSO ADVANCING EASTWARD OVER THE  
GREAT LAKES AND ON. EVEN WITH SOME CLOUD COVER PRESENT, MODERATE TO  
STRONG INSTABILITY WILL LIKELY BE IN PLACE ACROSS WESTERN NY BY LATE  
AFTERNOON, TO THE WEST OF A DIFFERENTIAL HEATING ZONE/FRONT.  
THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG/AHEAD OF A COLD FRONT  
FROM PARTS OF SOUTHEAST LOWER MI TO THE LOWER GREAT LAKES, WITH 50+  
KT OF DEEP-LAYER SHEAR SUPPORTING ORGANIZED UPDRAFTS. A MIX OF  
SUPERCELLS AND MULTICELLS WILL LIKELY POSE A THREAT FOR BOTH SEVERE  
HAIL AND SCATTERED TO NUMEROUS DAMAGING WINDS. SUFFICIENT LOW-LEVEL  
SHEAR SHOULD ALSO BE PRESENT TO SUPPORT A FEW TORNADOES, WITH SOME  
CHANCE FOR A STRONG TORNADO THIS EVENING IF A SUPERCELL MODE CAN BE  
MAINTAINED ACROSS WESTERN NY AND VICINITY. CONFIDENCE HAS INCREASED  
IN A CORRIDOR OF GREATER SEVERE/DAMAGING WIND POTENTIAL LATE THIS  
AFTERNOON/EVENING ACROSS PARTS OF WESTERN NY, WHERE AN ENHANCED RISK  
HAS BEEN INTRODUCED.  
   
..NORTHERN ROCKIES/HIGH PLAINS  
 
HIGH-BASED THUNDERSTORMS HAVE ALREADY DEVELOPED OVER THE HIGHER  
TERRAIN OF CENTRAL ID THIS MORNING. ENHANCED WINDS ALOFT ASSOCIATED  
WITH A NORTHEASTWARD-EJECTING MID-LEVEL SHORTWAVE TROUGH AND STEEP  
LOW-LEVEL LAPSE RATES WILL SUPPORT A RISK FOR SCATTERED  
SEVERE/DAMAGING WINDS AS THIS ACTIVITY SPREADS NORTHEASTWARD ACROSS  
MT THIS AFTERNOON AND EVENING. OCCASIONAL 75+ MPH GUSTS MAY OCCUR,  
EVEN THOUGH INSTABILITY SHOULD REMAIN WEAK. ISOLATED THUNDERSTORMS  
MAY ALSO DEVELOP LATER THIS EVENING/TONIGHT IN A LOW-LEVEL WARM  
ADVECTION REGIME ACROSS EASTERN MT INTO WESTERN ND, WITH SOME HAIL  
THREAT.  
   
..EASTERN UTAH INTO THE CENTRAL ROCKIES/HIGH PLAINS  
 
THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE THIS AFTERNOON  
OVER EASTERN UT INTO THE HIGHER TERRAIN OF NORTHERN/WESTERN CO AND  
SOUTHERN WY. THIS ACTIVITY WILL SPREAD NORTHEASTWARD INTO EASTERN  
WY/WESTERN NE WHERE A VERY DEEP/WELL-MIXED BOUNDARY LAYER SHOULD  
SUPPORT LOCALLY SEVERE GUSTS.  
 
..GLEASON/MOORE.. 09/02/2026  
 
 
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