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000 

WWUS20 KWNS 161858

SEL3

SPC WW 161858

ILZ000-INZ000-KYZ000-170100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 603

NWS STORM PREDICTION CENTER NORMAN OK

200 PM CDT THU AUG 16 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       EXTREME SOUTHEAST ILLINOIS

       SOUTHERN INDIANA

       EXTREME NORTH CENTRAL KENTUCKY



EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 200 PM UNTIL

800 PM CDT.



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 45

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 75 MILES WEST

SOUTHWEST OF BLOOMINGTON INDIANA TO 45 MILES NORTH NORTHEAST OF

LOUISVILLE KENTUCKY.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3).



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 602...



DISCUSSION...THE MCS IS SE IL MAY CONTINUE MOVING EWD/ESEWD ALONG

THE OUTFLOW BOUNDARY ACROSS SRN INDIANA...WHILE ADDITIONAL STORMS

DEVELOP ALONG THE BOUNDARY WHERE SURFACE HEATING HAS WEAKENED THE

CAP.  STRONG INSTABILITY AND MODEST /25-35 KT/ LOW-MID LEVEL WLY

WILL SUPPORT ORGANIZED MULTICELL CLUSTERS CAPABLE OF PRODUCING

DAMAGING WINDS AND ISOLATED LARGE HAIL THROUGH THE AFTERNOON.



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 550. MEAN STORM

MOTION VECTOR 27025.





...THOMPSON

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