URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 459
NWS STORM PREDICTION CENTER NORMAN OK
730 AM EDT THU JUN 18 2009
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
SOUTHEAST ILLINOIS
CENTRAL AND SOUTHERN INDIANA
CENTRAL KENTUCKY
EFFECTIVE THIS THURSDAY MORNING AND AFTERNOON FROM 730 AM UNTIL
100 PM EDT.
HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 70
STATUTE MILES EITHER SIDE OF A LINE FROM 25 MILES SOUTHEAST OF
LOUISVILLE KENTUCKY TO 50 MILES WEST SOUTHWEST OF TERRE HAUTE
INDIANA. 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 457...WW 458...
DISCUSSION...MATURE BOW ECHO TRACKING ACROSS CENTRAL IL IS LIKELY TO
PERSIST THROUGH THE MORNING HOURS AND TRACK INTO SOUTHERN IND AND
CENTRAL KY. STORMS ARE MOVING ALONG A STRONG INSTABILITY GRADIENT
AND SHOW CONSIDERABLE MESOSCALE ORGANIZATION. THIS IS EXPECTED TO
MAINTAIN RISK OF DAMAGING WINDS ACROSS THE WATCH AREA.
AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 31040.
...HART
