MESOSCALE DISCUSSION 0819
   NWS STORM PREDICTION CENTER NORMAN OK
   1226 PM CDT SAT MAY 22 2004
   
   AREAS AFFECTED...NERN OH...NRN PA...UPSTATE NY
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL 
   
   VALID 221726Z - 221900Z
   
   ...SEVERE THUNDERSTORMS MAY SOON EVOLVE OFF THE LAKE BREEZE FROM
   NERN OH INTO NWRN PA.  WW MAY BE REQUIRED...
   
   RAPID HEATING ALONG LAKE BREEZE HAS INITIATED CONVECTION OVER NERN
   OH AND NWRN PA.  THIS ACTIVITY SHOULD GRADUALLY INTENSIFY WITHIN
   BROAD WARM ADVECTION ZONE BENEATH WSWLY LLJ.  SIGNIFICANT
   MOISTURE/INSTABILITY ADVECTION SHOULD SPREAD NEWD ACROSS NRN PA INTO
   WRN NY OVER THE NEXT FEW HOURS.  SUFFICIENT DEEP LAYER SHEAR EXISTS
   FOR STORM ROTATION/SUPERCELLS. ALTHOUGH LARGE HAIL/DAMAGING WINDS
   WILL BE THE PRIMARY SEVERE THREATS...ISOLATED TORNADOES ARE
   POSSIBLE.
   
   ..DARROW.. 05/22/2004
   
   
   ATTN...WFO...BGM...BUF...CTP...PBZ...CLE...
   
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