

000 

WWUS20 KWNS 260012

SEL7

SPC WW 260012

ILZ000-INZ000-MOZ000-LMZ000-260300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 237

NWS STORM PREDICTION CENTER NORMAN OK

715 PM CDT FRI APR 25 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL AND NORTHEAST ILLINOIS

       EXTREME NORTHWEST INDIANA

       EAST CENTRAL MISSOURI

       LAKE MICHIGAN



EFFECTIVE THIS FRIDAY EVENING FROM 715 PM UNTIL 1000 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 40

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

NORTHWEST OF VALPARAISO INDIANA TO 20 MILES EAST SOUTHEAST OF

FARMINGTON MISSOURI.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU7).



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 231...WW 232...WW

233...WW 234...WW 235...



DISCUSSION...BROKEN LINE OF STORMS ALONG A COLD FRONT WILL SPREAD

EWD ACROSS ERN MO AND CENTRAL/NE IL THE NEXT FEW HOURS.  INSTABILITY

AND VERTICAL SHEAR WILL BE SUFFICIENT FOR A CONTINUED DAMAGING WIND

AND LARGE HAIL THREAT...BEFORE THE LOW LEVELS STABILIZE AND THE

THREAT ENDS BY ABOUT 03Z.



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 500. MEAN STORM

MOTION VECTOR 25030.





...THOMPSON

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