679  
ACUS11 KWNS 171616  
SWOMCD  
SPC MCD 171616  
NHZ000-VTZ000-MAZ000-NYZ000-171845-  
 
MESOSCALE DISCUSSION 0837  
NWS STORM PREDICTION CENTER NORMAN OK  
1116 AM CDT SAT MAY 17 2025  
 
AREAS AFFECTED...UPSTATE NEW YORK INTO VERMONT AND FAR WESTERN  
MASSACHUSETTS  
 
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE  
 
VALID 171616Z - 171845Z  
 
PROBABILITY OF WATCH ISSUANCE...60 PERCENT  
 
SUMMARY...STORMS WILL INCREASE IN COVERAGE AND INTENSITY THROUGH THE  
DAY, WITH AREAS OF HAIL, WIND, AND A COUPLE BRIEF TORNADOES  
POSSIBLE.  
 
DISCUSSION...IN THE WAKE OF THE EARLY DAY ACTIVITY OVER NORTHERN NY,  
SOUTHERLY WINDS CONTINUE TO DESTABILIZE THE AREA, WELL AHEAD OF THE  
COLD FRONT AND UPPER TROUGH MOVING IN FROM THE WEST. VISIBLE IMAGERY  
AND RADAR INDICATE WIDESPREAD BOUNDARY LAYER CUMULUS WITH A FEW  
STORMS BEGINNING TO FORM NEAR THE LAKE BREEZES AND OVER OTHER WELL  
HEATED TERRAIN FEATURES.  
 
COOLING ALOFT OVERSPREADING THE WARMING SURFACE AIR MASS WILL LEAD  
TO STEEPENING LAPSE RATES AND FURTHER DESTABILIZATION. WHILE NOT  
PARTICULARLY STRONG, DEEP LAYER SHEAR AND VEERING WINDS WITH HEIGHT  
WILL GENERALLY FAVOR CELLULAR DEVELOPMENT AHEAD OF THE COLD FRONT.  
THESE CELLS COULD PRODUCE HAIL, LOCALIZED WIND DAMAGE OR EVEN BRIEF  
TORNADOES AS 0-3 KM CAPE IS MAXIMIZED.  
 
AS THE PRIMARY COLD FRONT MOVES IN LATER, ADDITIONAL ACTIVITY OVER  
WESTERN NY AND PA COULD POSE MORE OF A WIND THREAT, SWEEPING IN  
BEHIND THE LEADING DAYTIME ACTIVITY. THE WIND SHIFT WILL BE  
PROMINENT, WITH OVER 30 KT WESTERLY LOW-LEVEL FLOW.  
 
..JEWELL/HART.. 05/17/2025  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT  
 
ATTN...WFO...GYX...BTV...ALY...BGM...BUF...  
 
LAT...LON 45057223 43617227 43187247 42837305 42537348 42237515  
42207605 42237722 42337792 42537824 42947827 43247788  
43417685 43587650 44247615 45037492 45057223  
 
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH  
MOST PROBABLE PEAK WIND GUST...55-70 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab SPC Page
Main Text Page