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INZ000-KYZ000-OHZ000-050200-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 568

NWS STORM PREDICTION CENTER NORMAN OK

345 PM EDT WED AUG 4 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       PARTS OF CENTRAL AND SOUTHERN INDIANA

       NORTHERN KENTUCKY

       SOUTHERN OHIO



EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 345 PM UNTIL

1000 PM EDT.



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 40

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 20 MILES NORTHWEST

OF TERRE HAUTE INDIANA TO 75 MILES EAST SOUTHEAST OF CINCINNATI

OHIO.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED

WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8).



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...THIS SEVERE THUNDERSTORM WATCH REPLACES

SEVERE THUNDERSTORM WATCH NUMBER 566. WATCH NUMBER 566 WILL NOT

BE IN EFFECT AFTER 345 PM EDT. CONTINUE...WW 567...



DISCUSSION...OUTFLOW BOUNDARY TRAILING FROM ONGOING MCS OVER SE OH

WILL CONTINUE TO SAG SWD TOWARD THE OH RIVER...PROVIDING A FOCUS FOR

ADDITIONAL THUNDERSTORM DEVELOPMENT.  THE BOUNDARY HAS STALLED

FARTHER NW ACROSS INDIANA...WHERE A FEED OF VERY HOT/UNSTABLE AIR

FROM THE WSW SHOULD SUPPORT NEW STORM FORMATION IN THE NEXT COUPLE

OF HOURS ACROSS CENTRAL/SRN INDIANA...AND STORMS COULD MOVE INTO

INDIANA FROM ERN IL.  THE COMBINATION OF STRONG INSTABILITY AND

30-40 KT MIDLEVEL FLOW WILL SUPPORT ORGANIZED MULTICELL CLUSTERS AND

PERHAPS MARGINAL SUPERCELL-TYPE STORMS...WITH A RISK FOR DAMAGING

WINDS AND LARGE HAIL THROUGH LATE EVENING.



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 30025.





...THOMPSON

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