THE NATIONAL WEATHER SERVICE IN PITTSBURGH HAS ISSUED A...

* SEVERE THUNDERSTORM WATCH

FOR THE FOLLOWING COUNTIES IN SOUTHWESTERN PENNSYLVANIA...

ALLEGHENEY. WESTMORELAND, WASHINGTON, GREENE

THIS WATCH IS IN EFFECT FROM 4:25 PM EDT UNTIL 11:00 PM EDT.

HAIL TO 2 INCHES IN DIAMETER, AND THUNDERSTORM WIND GUSTS TO 70 MPH AND DANGEROUS LIGHTNING ARE POSSIBLE WITHIN THE WATCH AREA.

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 TO NOAA WEATHER RADIO AND COMMERCIAL OUTLETS FOR LATER UPDATES AND POSSIBLE SEVERE WEATHER WARNINGS.

DISCUSSION...STORMS ARE INCREASING IN COVERAGE AND INTENSITY AS THEY MOVE INTO AN UNCAPPED AREA.  CURRENT ACTIVITY TO THE NORTH AND WEST OF THE FA WILL MOVE IN OVER THE NEXT FEW HRS.  STORMS ARE POPPING UP IN OH AND BECOMING ORGANIZED WITH THE MID LEVEL S/W ENERGY MOVING THRU.  UNI-DIRECTIONAL WIND FIELDS WILL ALLOW FOR ORGANIZED SMALL SCALE BOWING SEGMENTS.  BL-6KM VERTICAL SHEAR RANGING FROM 40-50KTS WILL ALLOW FOR STORMS TO ORGANIZE AND CONGEAL INTO A LINE OVER OH INTO W PA.