350  
ACUS03 KWNS 170732  
SWODY3  
SPC AC 170731  
 
DAY 3 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0231 AM CDT TUE JUN 17 2025  
 
VALID 191200Z - 201200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NEW ENGLAND  
INTO THE MID ATLANTIC...  
   
..SUMMARY
 
 
STRONG TO POTENTIALLY SEVERE THUNDERSTORMS ARE FORECAST ON THURSDAY  
FROM PARTS OF NEW ENGLAND INTO THE MID ATLANTIC AND CAROLINAS.  
   
..SYNOPSIS
 
 
A SEASONABLY DEEP MID/UPPER-LEVEL TROUGH IS FORECAST TO MOVE ACROSS  
PARTS OF SOUTHEASTERN CANADA AND ADJACENT PORTIONS OF THE NORTHEAST  
CONUS ON THURSDAY. IN CONJUNCTION WITH THIS TROUGH, A SURFACE  
CYCLONE IS EXPECTED TO MOVE FROM SOUTHEAST ONTARIO INTO SOUTHERN  
QUEBEC, AS A TRAILING COLD FRONT MOVES THROUGH PARTS OF THE  
NORTHEAST/NEW ENGLAND AND THE MID ATLANTIC.  
 
TO THE WEST, AN UPPER-LEVEL RIDGE WILL CONTINUE TO BUILD FROM THE  
SOUTHERN ROCKIES INTO PARTS OF THE CENTRAL GREAT PLAINS, WITH  
MULTIPLE MIDLEVEL SHORTWAVE TROUGHS EXPECTED TO MOVE FROM THE GREAT  
BASIN INTO THE NORTHERN ROCKIES AND HIGH PLAINS ALONG THE PERIPHERY  
OF THE RIDGE.  
 
...PARTS OF NEW ENGLAND SOUTHWARD INTO THE MID ATLANTIC, CAROLINAS,  
AND SOUTHEAST...  
RICH LOW-LEVEL MOISTURE WILL ALREADY BE IN PLACE ACROSS PARTS OF THE  
CAROLINAS AND MID ATLANTIC THURSDAY MORNING, WITH SOME NORTHWARD  
MOISTURE TRANSPORT EXPECTED THROUGH THE DAY ALONG/AHEAD OF THE  
APPROACHING FRONT. GUIDANCE CONTINUES TO VARY SOMEWHAT REGARDING  
TIMING OF THE FRONT, AND ALSO THE EXTENT TO WHICH STRONGER  
MID/UPPER-LEVEL FLOW LAGS BEHIND THE FRONT. HOWEVER, IN GENERAL,  
MODERATE DESTABILIZATION IS EXPECTED INTO AT LEAST SOUTHERN NEW  
ENGLAND BY AFTERNOON, AND PERHAPS FARTHER NORTH DEPENDING ON  
LINGERING CLOUDINESS AND FRONTAL TIMING.  
 
SCATTERED THUNDERSTORM DEVELOPMENT WILL BE POSSIBLE ALONG/AHEAD OF  
THE FRONT FROM THE CAROLINAS/MID ATLANTIC INTO NEW ENGLAND DURING  
THE AFTERNOON. WIND FIELDS WILL GENERALLY BE STRONGER WITH NORTHWARD  
EXTENT. DEPENDING ON THE EXTENT OF DESTABILIZATION, SUPERCELLS AND  
ORGANIZED CLUSTERS WILL BE POSSIBLE ACROSS PARTS OF NEW ENGLAND AND  
PERHAPS THE NORTHERN MID ATLANTIC, WHICH WOULD POSE SOME THREAT OF  
ALL SEVERE HAZARDS. FARTHER SOUTH INTO THE SOUTHERN MID ATLANTIC AND  
CAROLINAS, DEEP-LAYER SHEAR WILL BE WEAKER, BUT FAVORABLE LOW-LEVEL  
MOISTURE, STRONG BUOYANCY, AND MODEST MIDLEVEL SOUTHWESTERLIES WILL  
SUPPORT OUTFLOW-DRIVEN CLUSTERS CAPABLE OF DAMAGING WINDS AND  
POSSIBLY SOME HAIL.  
 
THE ORGANIZED SEVERE THREAT WILL TEND TO DECREASE WITH SOUTHWESTWARD  
EXTENT, DUE TO WEAKER DEEP-LAYER FLOW. HOWEVER, FAVORABLE LOW-LEVEL  
MOISTURE AND BUOYANCY COULD SUPPORT A FEW STRONG TO LOCALLY SEVERE  
STORMS ALONG THE TRAILING COLD FRONT INTO PARTS OF THE SOUTHEAST  
DURING THE LATE AFTERNOON AND EVENING.  
   
..PARTS OF THE UPPER GREAT LAKES/MIDWEST
 
 
IN THE WAKE OF THE DEPARTING MID/UPPER-LEVEL SHORTWAVE TROUGH,  
MODEST LINGERING LOW-LEVEL MOISTURE BENEATH RELATIVELY COOL  
TEMPERATURES ALOFT MAY SUPPORT MODERATE DIURNAL DESTABILIZATION  
ACROSS PARTS OF THE UPPER GREAT LAKES AND MIDWEST. SOME GUIDANCE  
DEVELOPS SOUTHEASTWARD-MOVING CONVECTION ACROSS PARTS OF NORTHEAST  
MN INTO NORTHERN WI DURING THE AFTERNOON, POSSIBLY IN RESPONSE TO A  
MIDLEVEL JETLET APPROACHING THE UPPER MIDWEST FROM THE NORTHWEST.  
THIS SCENARIO IS UNCERTAIN, BUT MODERATE MIDLEVEL NORTHWESTERLY FLOW  
AND SUFFICIENT DEEP-LAYER SHEAR WOULD SUPPORT AT LEAST AN ISOLATED  
SEVERE THREAT IF CONVECTION CAN BE SUSTAINED DURING THE AFTERNOON  
AND EVENING. OTHER STRONG STORMS MAY DEVELOP THURSDAY NIGHT WITHIN A  
WARM-ADVECTION REGIME.  
   
..NORTHERN PLAINS
 
 
INCREASING LOW-LEVEL SOUTHERLY FLOW WILL AID IN LOW-LEVEL MOISTURE  
RETURN ACROSS PARTS OF THE CENTRAL/NORTHERN PLAINS ON THURSDAY.  
STRONG DIURNAL HEATING WILL RESULT IN MLCAPE INCREASING ABOVE 2000  
J/KG INTO PARTS OF THE DAKOTAS AND NEBRASKA. WIND PROFILES WILL  
SUPPORT ORGANIZED CONVECTION, AND MLCINH MAY BE MOSTLY ERODED BY  
LATE AFTERNOON, THOUGH POTENTIAL FOR STORM DEVELOPMENT INTO EVENING  
IS HIGHLY UNCERTAIN, GIVEN THE PRESENCE OF RISING MIDLEVEL HEIGHTS  
AND GENERALLY LIMITED LARGE-SCALE ASCENT.  
 
LATER THURSDAY EVENING INTO THE OVERNIGHT, A NOCTURNAL LOW-LEVEL JET  
MAY AID IN ELEVATED STORM DEVELOPMENT, THOUGH THE DETAILS OF ANY  
SEVERE THREAT ASSOCIATED WITH THIS POTENTIAL LATE-PERIOD CONVECTION  
REMAIN UNCERTAIN AT THIS TIME.  
 
..DEAN.. 06/17/2025  
 

 
 
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