

074 

WWUS20 KWNS 092102

SEL8

SPC WW 092102

ILZ000-INZ000-100200-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 568

NWS STORM PREDICTION CENTER NORMAN OK

405 PM CDT THU AUG 9 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       EAST CENTRAL ILLINOIS

       WEST CENTRAL INDIANA



EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 405 PM UNTIL

900 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 80

STATUTE MILES EAST AND WEST OF A LINE FROM 45 MILES NORTH

NORTHWEST OF LAFAYETTE INDIANA TO 35 MILES SOUTHEAST OF CHAMPAIGN

ILLINOIS.  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...CONTINUE...WW 567...



DISCUSSION...CONVECTION WILL LIKELY INCREASE SOME IN

COVERAGE/INTENSITY AS SURFACE HEATING PERSISTS IN A ZONE OF ASCENT

SPREADING SEWD IN ADVANCE OF A PRONOUNCED SHORTWAVE TROUGH OVER THE

UPPER MS VALLEY.  GIVEN THE MODERATE INSTABILITY AND DEEP-LAYER

WNWLY SHEAR...A FEW ORGANIZED MULTICELLS/SUPERCELLS WILL BE CAPABLE

OF PRODUCING DAMAGING WINDS AND LARGE HAIL THROUGH THIS 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 450. MEAN STORM

MOTION VECTOR 29030.





...THOMPSON

