558  
ACUS03 KWNS 121928  
SWODY3  
SPC AC 121927  
 
DAY 3 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0227 PM CDT FRI JUN 12 2026  
 
VALID 141200Z - 151200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SUNDAY ACROSS MUCH  
OF THE NORTHERN MID ATLANTIC COAST STATES...  
   
..SUMMARY
 
 
SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS THE LOWER GREAT LAKES AND  
UPPER OHIO VALLEY VICINITY THROUGH MUCH OF THE NORTHERN MID ATLANTIC  
SUNDAY.  
   
..DISCUSSION
 
 
DOWNSTREAM OF INITIALLY AMPLIFIED MID-LEVEL RIDGING OFFSHORE OF THE  
PACIFIC COAST, MODELS INDICATE THAT FLOW WILL CONTINUE TO TREND  
CYCLONIC EAST OF THE ROCKIES THROUGH THE ATLANTIC SEABOARD, TO THE  
SOUTH OF A BROADENING VORTEX CENTERED NEAR SOUTHERN HUDSON BAY.  
WITHIN THIS REGIME, IT APPEARS THAT NOTABLE SHORT WAVE TROUGHING  
WILL PIVOT EAST OF THE UPPER MIDWEST THROUGH THE SOUTHEASTERN  
CANADIAN PROVINCES AND NORTHEAST BY LATE SUNDAY NIGHT, ACCOMPANIED  
BY CYCLOGENESIS ACROSS THE LOWER GREAT LAKES THROUGH ST. LAWRENCE  
VALLEY VICINITY. IT APPEARS THAT THIS MAY BE PRECEDED BY THE  
REMNANTS OF AN INITIALLY FAIRLY NOTABLE MESOSCALE CONVECTIVE VORTEX,  
WITHIN STRENGTHENING WESTERLY FLOW ACROSS THE ALLEGHENY/CUMBERLAND  
PLATEAU THROUGH THE NORTHERN MID ATLANTIC BY EARLY SUNDAY EVENING.  
   
..NORTHEAST
 
 
THERE REMAINS CONSIDERABLE SPREAD WITHIN THE LATEST MODEL OUTPUT  
CONCERNING THE EXTENT OF CONVECTIVE POTENTIAL FOR THIS PERIOD.  
MOSTLY THIS APPEARS RELATED PRE-FRONTAL LOW-LEVEL MOISTURE RETURN  
AND DESTABILIZATION ACROSS THE UPPER OHIO VALLEY INTO THE LEE OF THE  
LOWER GREAT LAKES, WHICH COULD BE SLOWED OR IMPEDED BY THE INFLUENCE  
OF PRECEDING CONVECTIVE OUTFLOW. HOWEVER, GUIDANCE GENERALLY  
SUGGESTS THAT DESTABILIZATION PRIOR TO THE ARRIVAL OF THE MCV AND  
BELT OF ENHANCED LOWER/MID-TROPOSPHERIC WIND FIELDS (30-40+ KT) WILL  
BE SUFFICIENT TO SUPPORT POTENTIAL FOR ORGANIZED SEVERE CONVECTION  
EAST OF THE ALLEGHENY MOUNTAINS THROUGH THE NORTHERN MID ATLANTIC BY  
LATE SUNDAY AFTERNOON. MORE SUBSTANTIVE STRENGTHENING OF MID-LEVEL  
WIND FIELDS AND FORCING FOR ASCENT APPEAR LIKELY TO OVERSPREAD THE  
PRE-FRONTAL ENVIRONMENT ACROSS PARTS OF THE UPPER OHIO VALLEY INTO  
THE LEE OF THE LOWER GREAT LAKES REGION, WHERE IT APPEARS INCREASING  
MODEL OUTPUT IS NOW SUGGESTING THAT THE EVOLVING WARM SECTOR MAY  
BECOME SUFFICIENTLY UNSTABLE TO SUPPORT A RISK FOR ORGANIZED SEVERE  
STORM DEVELOPMENT.  
 
DAMAGING WIND GUSTS ACCOMPANYING ORGANIZING LINES AND/OR CLUSTERS  
APPEAR THE PRIMARY SEVERE HAZARD, BUT THERE ALSO APPEARS AT LEAST  
SOME POTENTIAL FOR A FEW TORNADOES. IT IS STILL POSSIBLE THAT  
SEVERE WEATHER PROBABILITIES WILL NEED TO BE INCREASED FURTHER IN  
LATER OUTLOOK UPDATES FOR THIS PERIOD.  
 
..KERR.. 06/12/2026  
 

 
 
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