SEL9
   
   URGENT - IMMEDIATE BROADCAST REQUESTED
   SEVERE THUNDERSTORM WATCH NUMBER 179...RESENT
   NWS STORM PREDICTION CENTER NORMAN OK
   825 PM CDT THU APR 13 2006
   
   THE NWS STORM PREDICTION CENTER HAS ISSUED A
   SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 
   
          NORTHERN ILLINOIS
          EXTREME NORTHWEST INDIANA
          CENTRAL AND SOUTHEAST WISCONSIN
          LAKE MICHIGAN
   
   EFFECTIVE THIS THURSDAY NIGHT AND FRIDAY MORNING FROM 825 PM
   UNTIL 300 AM CDT.
   
   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 80
   STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH
   NORTHEAST OF OSHKOSH WISCONSIN TO 45 MILES SOUTH SOUTHWEST OF
   MARSEILLES ILLINOIS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE
   THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU9).
   
   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 178...
   
   DISCUSSION...CLUSTER OF SUPERCELLS IN ERN IA WILL CONTINUE EWD
   ACROSS NRN IL TONIGHT...WITH AN INCREASING THREAT FOR WIND DAMAGE AS
   THE STORMS MERGE INTO A LARGER MCS AND MOVE INTO AN ENVIRONMENT WITH
   RESIDUAL STEEP L0W-LEVEL LAPSE RATES.  THE LARGE HAIL THREAT WILL
   ALSO CONTINUE GIVEN THE FEED OF STRONG INSTABILITY FROM THE SW. 
   FARTHER N...A SEPARATE CLUSTER OF STORMS IS BEGINNING TO DEVELOP
   NEAR EAU...AND THIS CONVECTION SHOULD SPREAD EWD/ESEWD ALONG AND N
   OF THE SURFACE WARM FRONT.  THE PRIMARY THREAT THIS AREA WILL BE
   LARGE HAIL WITH STORMS BASED ABOVE THE SURFACE.
   
   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 500. MEAN STORM
   MOTION VECTOR 27035.
   
   
   ...THOMPSON