MESOSCALE DISCUSSION 0778
   NWS STORM PREDICTION CENTER NORMAN OK
   1052 AM CDT SAT MAY 09 2009
   
   AREAS AFFECTED...MUCH OF NY THROUGH SRN AND CNTRL VT
   
   CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 
   
   VALID 091552Z - 091715Z
   
   STORMS ARE EXPECTED TO DEVELOP EWD THROUGH NY AND EVENTUALLY INTO VT
   THIS AFTERNOON. LARGE HAIL...DAMAGING WIND AND ISOLATED TORNADOES
   WILL BE POSSIBLE. WW WILL LIKELY BE NEEDED BEFORE 17Z.
   
   AT MID-DAY A COLD FRONT EXTENDS FROM A SURFACE LOW IN SRN ONTARIO
   SWWD THROUGH THE OH VALLEY. THE LOW SHOULD DEVELOP EAST INTO NY THIS
   AFTERNOON WITHIN ZONE OF DPVA AND ASCENT DOWNSTREAM FROM EWD MOVING
   SHORTWAVE TROUGH OVER THE GREAT LAKES. AXIS OF UPPER 50S DEWPOINTS
   HAS SPREAD THROUGH PRE-FRONTAL WARM SECTOR. WIDESPREAD CLOUDS ARE
   SLOWING DIABATIC HEATING SOMEWHAT...BUT SUFFICIENT BREAKS EXIST TO
   BOOST TEMPERATURES INTO THE MID 70S BY EARLY AFTERNOON. SOMEWHAT
   LIMITED LOW LEVEL MOISTURE AND MODEST MID LEVEL LAPSE RATES WILL
   LIMIT MLCAPE TO AOB 1000 J/KG. STORMS CURRENTLY DEVELOPING OVER LAKE
   ERIE AND LAKE ONTARIO COULD BEGIN TO AFFECT NWRN PORTIONS OF NY BY
   16Z. ADDITIONAL STORMS ARE LIKELY TO DEVELOP FARTHER EAST AS THE
   BOUNDARY LAYER DESTABILIZES. AN 80+ KT UPPER JET MAX ATTENDING THE
   GREAT LAKES IMPULSE WILL ADVANCE EWD INTO THE NERN STATES THIS
   AFTERNOON ACCOMPANIED BY A SWLY 30 KT LOW LEVEL JET. BULK SHEAR OF
   50+ KT AND 150-250 M2/S2 WILL SUPPORT SUPERCELLS AND BOWING
   SEGMENTS.
   
   ..DIAL.. 05/09/2009
   
   
   ATTN...WFO...BTV...ALY...BGM...BUF...
   
   LAT...LON   44117297 42947261 42287431 42137828 42837847 43257666
               44437523 44117297