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001 

WWUS20 KWNS 260049

SEL7

SPC WW 260049

IAZ000-ILZ000-MOZ000-260800-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 187

NWS STORM PREDICTION CENTER NORMAN OK

745 PM CDT WED APR 25 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHEAST IOWA

       WESTERN AND CENTRAL ILLINOIS

       NORTHEAST MISSOURI



EFFECTIVE THIS WEDNESDAY NIGHT AND THURSDAY MORNING FROM 745 PM

UNTIL 300 AM CDT.



HAIL TO 2 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 60

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 60 MILES WEST

NORTHWEST OF QUINCY ILLINOIS TO 40 MILES SOUTH SOUTHEAST OF

DECATUR ILLINOIS.  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.



DISCUSSION...ISOLD TO POSSIBLY SCTD TSTMS EXPECTED TO PERSIST/FORM

IN LOW LVL WAA ZONE NEAR/EAST OF NE MO SFC LOW.  OTHER STORMS MAY

FORM LATER THIS EVE ALONG DIFFUSE NW-SE WARM FRONT THROUGH CNTRL IL.

SUSTAINED UPDRAFTS WILL HAVE POTENTIAL FOR LARGE HAIL AND POSSIBLY

DMGG WIND GIVEN LOCATION OF WW AREA ON ERN FRINGE OF LARGE/DEEP EML.

CLOUD LAYER SHEAR APPEARS FAVORABLE FOR SUPERCELLS AND POSSIBLY

STORM SPLITS.



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

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM

MOTION VECTOR 33025.





...CORFIDI

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