321  
ACUS11 KWNS 301602  
SWOMCD  
SPC MCD 301601  
MEZ000-NHZ000-VTZ000-301900-  
 
MESOSCALE DISCUSSION 1846  
NWS STORM PREDICTION CENTER NORMAN OK  
1101 AM CDT WED JUL 30 2025  
 
AREAS AFFECTED...CENTRAL MAINE...PORTIONS OF NORTHERN NEW HAMPSHIRE  
AND VERMONT  
 
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY  
 
VALID 301601Z - 301900Z  
 
PROBABILITY OF WATCH ISSUANCE...20 PERCENT  
 
SUMMARY...SCATTERED THUNDERSTORM ACTIVITY DEVELOPING OVER THE NEXT  
FEW HOURS MAY INCREASINGLY POSE A RISK FOR SMALL TO MARGINALLY  
SEVERE HAIL AND LOCALIZED POTENTIALLY DAMAGING WIND GUSTS BY 3-5 PM  
EDT.  
 
DISCUSSION...A CORRIDOR OF STRONGER, BUT MODEST, DESTABILIZATION IS  
UNDERWAY ACROSS PARTS OF SOUTHEASTERN ONTARIO AND ADJACENT QUEBEC  
THROUGH PORTIONS OF CENTRAL MAINE. THIS IS OCCURRING IN RESPONSE TO  
CONTINUING INSOLATION, BENEATH THE SOUTHERN PERIPHERY OF A BROAD  
MID-LEVEL COLD POOL ASSOCIATED WITH UPPER TROUGHING SLOWLY DIGGING  
ACROSS THE EASTERN CANADIAN PROVINCES. FORECAST SOUNDINGS SUGGEST  
THAT RELATIVELY WARM AIR ASSOCIATED WITH BROAD, INCREASINGLY  
SUPPRESSED, RIDGING FURTHER ALOFT MAY LIMIT THE MAGNITUDE OF  
DEVELOPING CAPE, BUT THERMODYNAMIC PROFILES MAY STILL BE  
SUFFICIENTLY COOL AND UNSTABLE IN MID-LEVELS TO SUPPORT A RISK FOR  
SMALL TO MARGINALLY SEVERE HAIL.  
 
ALTHOUGH LOW-LEVEL WIND FIELDS ARE RATHER MODEST, DEEP-LAYER SHEAR  
ASSOCIATED WITH A WESTERLY JET IN MID/UPPER-LEVELS IS STRONG. FLOW  
ON THE ORDER OF 30-50 KT APPEARS AS LOW AS THE 700-500 LAYER,  
CONTRIBUTING TO MEAN FLOW AROUND 25-30 KTS IN THE LOWEST 6 KM AGL.  
THIS MAY GRADUALLY SUPPORT MODEST EAST-SOUTHEAST STORM MOTIONS, AND  
POTENTIAL FOR LOCALLY STRONG TO SEVERE SURFACE GUSTS, AS LOW-LEVEL  
LAPSE RATES CONTINUE TO STEEPEN AND THUNDERSTORM ACTIVITY  
INTENSIFIES IN PEAK AFTERNOON DESTABILIZATION.  
 
DEEPENING CONVECTIVE DEVELOPMENT IS ALREADY UNDERWAY OFF THE HIGHER  
TERRAIN WEST OF HOULTON THROUGH NORTHWEST OF BANGOR, UPSTREAM INTO  
THE UPPER ST. LAWRENCE VALLEY. THIS LIKELY WILL STRENGTHEN WITH THE  
INITIATION OF SCATTERED THUNDERSTORM ACTIVITY DURING THE NEXT FEW  
HOURS.  
 
..KERR/SMITH.. 07/30/2025  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...CAR...GYX...BTV...  
 
LAT...LON 45696719 44976870 44657152 44657252 45467339 45887244  
46097044 46506854 46316779 45696719  
 
MOST PROBABLE PEAK WIND GUST...55-70 MPH  
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN  
 
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