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262 

WWUS20 KWNS 282037

SEL8

SPC WW 282037

INZ000-KYZ000-290300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 198

NWS STORM PREDICTION CENTER NORMAN OK

435 PM EDT SAT APR 28 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHERN INDIANA

       NORTHERN KENTUCKY



EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 435 PM UNTIL

1100 PM EDT.



HAIL TO 2.5 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 35 MILES SOUTH

SOUTHWEST OF TERRE HAUTE INDIANA TO 25 MILES NORTH NORTHEAST OF

LEXINGTON KENTUCKY.  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 197...



DISCUSSION...TSTMS CURRENTLY ACROSS SRN IL ARE EXPECTED TO EXPAND

AND SPREAD EAST ACROSS PORTIONS OF SRN IND AND THEN ACROSS THE OH

RIVER INTO NRN KY THROUGH THIS EVENING. THIS ACTIVITY IS OCCURRING

NEAR A WEAK SURFACE LOW AND ALONG A WARM/QUASI-STATIONARY FRONT FROM

NEAR STL ESEWD TO NEAR LMK. AIR MASS FUELING ONGOING AND ANTICIPATED

DEVELOPMENT IS MODERATELY TO STRONGLY UNSTABLE AND WILL CONTINUE TO

SUPPORT STOUT STORM UPDRAFTS AMIDST MORE THAN SUFFICIENT VERTICAL

SPEED SHEAR FOR STORM ORGANIZATION AND SUPERCELL STRUCTURES.

GREATEST THREAT IN THE SHORT TERM WILL BE THE PROSPECT FOR LARGE

HAIL. DAMAGING WIND POTENTIAL MAY INCREASE AS CLUSTERS MERGE...GROW

UPSCALE...AND THEN RESULT IN A DEEPENING COLD POOL AND MCS

ACCELERATING ESEWD ACROSS THE OH RIVER. A NARROW CORRIDOR OF TORNADO

POTENTIAL ALSO EXISTS INVOF SHARP FRONTAL ZONE BUT THIS POTENTIAL

APPEARS TOO LOCALIZED ATTM TO SUPPORT A TORNADO WATCH FOR THE LARGER

AREA AT RISK FROM HAIL AND HIGH WINDS.



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

TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 28030.





...CARBIN

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