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WWUS20 KWNS 162030

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ILZ000-INZ000-KYZ000-MOZ000-170400-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 583

NWS STORM PREDICTION CENTER NORMAN OK

330 PM CDT THU AUG 16 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHERN ILLINOIS

       SOUTHERN INDIANA

       WESTERN KENTUCKY

       SOUTHEAST MISSOURI



EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 330 PM UNTIL

1100 PM CDT.



HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 75

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 75

STATUTE MILES EAST AND WEST OF A LINE FROM 35 MILES NORTH

NORTHEAST OF BLOOMINGTON INDIANA TO 40 MILES SOUTH OF PADUCAH

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 582...



DISCUSSION...STORMS ARE CONSOLIDATING ALONG A COLD FRONT MOVING SEWD

FROM IL/WRN IND SWWD TO MO THIS AFTERNOON. A VERY WARM AND MOIST

AIRMASS AHEAD OF THE FRONT WILL RESULT IN SUFFICIENT INSTABILITY TO

SUSTAIN STRONG TO SEVERE STORMS AS THE FRONT SETTLES SEWD TOWARD THE

LOWER OH VALLEY AND CONFLUENCE OF THE OH/MS RIVERS THROUGH THIS

EVENING. DEEP-LAYER WLY FLOW IS FORECAST TO STRENGTHEN COINCIDENT

WITH THE FRONTAL ADVANCE AND SHOULD SUPPORT AND INCREASE IN STORM

MOTION AND ORGANIZATION...ESPECIALLY ACROSS ERN IL AND SRN IND.

SLIGHTLY WEAKER MID LEVEL FLOW WITH SWD/SWWD EXTENT WILL LIKELY BE

COMPENSATED FOR BY GREATER DESTABILIZATION IN THESE AREAS TO SUPPORT

VIGOROUS STORMS WITH SOME HAIL AND SEVERE WIND POTENTIAL.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 65

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 600. MEAN STORM

MOTION VECTOR 31030.





...CARBIN

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