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WWUS20 KWNS 072241

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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 739

NWS STORM PREDICTION CENTER NORMAN OK

540 PM CDT SUN AUG 7 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL AND SOUTHERN ILLINOIS

       EAST CENTRAL AND SOUTHEAST MISSOURI



EFFECTIVE THIS SUNDAY AFTERNOON AND MONDAY MORNING FROM 540 PM

UNTIL 100 AM 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 95

STATUTE MILES EAST AND WEST OF A LINE FROM 25 MILES NORTH

NORTHWEST OF SALEM ILLINOIS TO 50 MILES SOUTHWEST OF FARMINGTON

MISSOURI.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU9).



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 734...WW 735...WW

736...WW 737...WW 738...



DISCUSSION...COMPLEX CONVECTIVE SYSTEM IN CNTRL MO EXPECTED TO

CONTINUE GENERALLY E OR ESE AT ABOUT 35 KTS...WITH OCCASIONAL

STRONGER FORWARD-PROPAGATING SURGES AROUND 45 KTS.  THERMODYNAMIC

AND WIND ENVIRONMENT APPEAR FAVORABLE FOR ADDITIONAL

FORWARD-PROPAGATING SEGMENTS INTO STRONGLY HEATED/VERY MOIST AIR

OVER ERN MO AND WRN/SRN IL /REF MCD 1888/.



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 550. MEAN STORM

MOTION VECTOR 28035.





...CORFIDI

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