MESOSCALE DISCUSSION 1487
   NWS STORM PREDICTION CENTER NORMAN OK
   0530 PM CDT TUE JUL 17 2012
   
   AREAS AFFECTED...UPSTATE NY INTO NRN NEW ENGLAND
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 489...
   
   VALID 172230Z - 172330Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 489
   CONTINUES.
   
   SUMMARY...ISOLATED SEVERE THREAT REMAINS ALONG A CORRIDOR OF
   STRONG/SEVERE THUNDERSTORMS THAT WILL SPREAD SEWD ACROSS UPSTATE NY
   AND PORTIONS OF NEW ENGLAND THIS EVENING.
   
   DISCUSSION...LEADING EDGE OF DISORGANIZED MCS IS SPREADING SEWD AT
   ROUGHLY 25-30KT ACROSS CNTRL VT/NH.  THIS ACTIVITY WILL LIKELY
   MAINTAIN ITS INTENSITY AS IT SPREADS INTO SRN ME AND PERHAPS AS FAR
   SOUTH AS THE MA BORDER.  WITH SWLY LOW LEVEL TRAJECTORIES ACROSS SRN
   NEW ENGLAND MORE THAN ADEQUATE INSTABILITY IS IN PLACE AND LOW LEVEL
   LAPSE RATES ARE FAIRLY STEEP WITH SFC-3KM VALUES NEAR 8 C/KM. 
   STRONG DOWNBURSTS AND MARGINALLY SEVERE HAIL ARE THE MAIN THREATS
   WITH THIS ACTIVITY.
   
   WILL MONITOR AREAS JUST SOUTH OF WW489 FOR POSSIBLE WATCH BUT IT/S
   NOT ENTIRELY CLEAR HOW FAR SOUTH THIS ACTIVITY WILL SPREAD.
   
   ..DARROW.. 07/17/2012
   
   
   ATTN...WFO...GYX...BTV...ALY...BGM...BUF...
   
   LAT...LON   44707623 45287043 43557042 42987623 44707623