MESOSCALE DISCUSSION 1685
   NWS STORM PREDICTION CENTER NORMAN OK
   0906 PM CDT SUN JUL 26 2009
   
   AREAS AFFECTED...ERN PA...NRN NJ...SERN NY...AND SRN NEW ENGLAND
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 626...
   
   VALID 270206Z - 270300Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 626
   CONTINUES.
   
   THREAT FOR ISOLATED DAMAGING WIND AND HAIL MAY PERSIST FOR ANOTHER
   HOUR OR SO MAINLY FROM NJ...SERN NY AND SRN NEW ENGLAND. SEVERE
   POTENTIAL IS BECOMING INCREASINGLY MARGINAL AND WW 626 WILL BE
   ALLOWED TO EXPIRE AT 03Z WITH NO FURTHER WW ISSUANCE ANTICIPATED.
   
   OVERALL TENDENCY HAS BEEN FOR THE STORMS TO GRADUALLY WEAKEN AND
   THIS TREND IS EXPECTED TO CONTINUE THIS EVENING. THE 00Z RAOBS FROM
   ALB AND OKX SHOWED WEAK INSTABILITY /500-1000 J/KG MLCAPE/ BASED ON
   SURFACE TEMPERATURES IN THE 70S. THE ATMOSPHERE OVER MUCH OF THIS
   REGION HAS BEEN STABILIZED BY PREVIOUS CONVECTION. WITH THE ONSET OF
   NOCTURNAL COOLING...THE THERMODYNAMIC ENVIRONMENT WILL BECOME TOO
   MARGINAL TO SUPPORT ROBUST CONVECTION BEYOND 03Z.
   
   ..DIAL.. 07/27/2009
   
   
   ATTN...WFO...BOX...OKX...ALY...PHI...
   
   LAT...LON   41437233 40897362 40237446 39987481 40257524 41037473
               41587377 41837271 41437233