SEL7
   
   URGENT - IMMEDIATE BROADCAST REQUESTED
   SEVERE THUNDERSTORM WATCH NUMBER 157
   NWS STORM PREDICTION CENTER NORMAN OK
   425 PM EDT TUE APR 12 2005
   
   THE NWS STORM PREDICTION CENTER HAS ISSUED A
   SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 
   
          NORTH GEORGIA
          UPSTATE AND PIEDMONT SOUTH CAROLINA
   
   EFFECTIVE THIS TUESDAY AFTERNOON FROM 425 PM UNTIL MIDNIGHT EDT.
   
   HAIL TO 2 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 135
   STATUTE MILES EAST AND WEST OF A LINE FROM 45 MILES NORTHWEST OF
   ANDERSON SOUTH CAROLINA TO 55 MILES SOUTH SOUTHEAST OF ATHENS
   GEORGIA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED
   WATCH OUTLINE UPDATE (WOUS64 KWNS WOU7).
   
   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 156...
   
   DISCUSSION...THUNDERSTORMS EXPECTED TO INCREASE IN
   COVERAGE/INTENSITY ACROSS WW AREA DURING THE NEXT FEW HOURS AS
   SURFACE HEATING AND MESOSCALE ASCENT AHEAD OF AL UPPER IMPULSE /PER
   WV IMAGERY/ FURTHER DESTABILIZE REGION.  RELATIVELY STEEP MID LEVEL
   LAPSE RATES AND 40 KT DEEP WSWLY SHEAR SHOULD SUPPORT ORGANIZED
   STORMS/SUPERCELLS WITH HAIL AND DAMAGING WIND. IF STORMS REMAIN
   DISCRETE...ERN HALF OF WATCH WILL HAVE TO BE MONITORED FOR THE
   POSSIBILITY THAT THE CELLS WILL INTERACT WITH SHALLOW LAYER OF
   MOIST/BACKED FLOW INVOF WNW/ESE BOUNDARY N OF AHN.  SUCH INTERACTION
   COULD YIELD A TORNADO THREAT...AND REQUIRE UPGRADE TO A TORNADO
   WATCH LATER THIS EVENING.
   
   AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
   TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
   KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM
   MOTION VECTOR 26030.
   
   
   ...CORFIDI