

000 

WWUS20 KWNS 282230

SEL5

SPC WW 282230

MDZ000-NYZ000-PAZ000-VAZ000-WVZ000-LEZ000-LOZ000-290500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 635

NWS STORM PREDICTION CENTER NORMAN OK

630 PM EDT SAT JUN 28 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN MARYLAND

       WESTERN AND CENTRAL NEW YORK

       A LARGE PART OF PENNSYLVANIA

       NORTHWESTERN VIRGINIA

       THE EASTERN PANHANDLE OF WEST VIRGINIA

       LAKE ERIE

       LAKE ONTARIO



EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 630 PM

UNTIL 100 AM EDT.



HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 80

STATUTE MILES EAST AND WEST OF A LINE FROM 15 MILES NORTHEAST OF

ROCHESTER NEW YORK TO 35 MILES WEST SOUTHWEST OF MARTINSBURG WEST

VIRGINIA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5).



REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE

FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH

AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR

THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS

AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY

DO PRODUCE TORNADOES.



OTHER WATCH INFORMATION...CONTINUE...WW 629...WW 630...WW

631...WW 633...WW 634...



DISCUSSION...BROKEN LINES OF TSTMS IN ERN OH/WRN PA EXPECTED TO

CONTINUE ENE AT ABOUT 30 KTS.  OTHER STORMS FORMING AHEAD OF THESE

LINES OVER THE WRN SLOPES OF THE PA MTNS AND OVER ERN WV SHOULD ALSO

CONTINUE ENEWD.  RELATIVELY STEEP LOW LVL LAPSE RATES AND

MODERATE...UNIDIRECTIONAL WSWLY LOW LVL FLOW SUGGEST POTENTIAL FOR

LOCALLY DMGG WINDS AND POSSIBLY MARGINALLY SVR HAIL /REF MCD 1619/.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 26030.





...CORFIDI

