

000 

WWUS20 KWNS 290001

SEL2

SPC WW 290001

ILZ000-MOZ000-290600-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 872

NWS STORM PREDICTION CENTER NORMAN OK

700 PM CDT THU AUG 28 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WEST CENTRAL AND SOUTHWEST ILLINOIS

       CENTRAL AND SOUTHERN MISSOURI



EFFECTIVE THIS THURSDAY NIGHT AND FRIDAY MORNING FROM 700 PM

UNTIL 100 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 70

STATUTE MILES EITHER SIDE OF A LINE FROM 25 MILES NORTHWEST OF

SPRINGFIELD ILLINOIS TO 30 MILES SOUTH OF VICHY MISSOURI.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU2).



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 871...



DISCUSSION...LINEAR MCS HAS DEVELOPED FROM EAST CENTRAL KS ACROSS

CENTRAL MO INTO NERN MO.  THE LINE HAS EXHIBITED PERIODIC

LEWPS/BOWING SEGMENTS ...PARTICULARLY ACROSS NERN MO...THAT ARE

ASSOCIATED WITH STRONGER WIND GUST POTENTIAL.  UNSTABLE ENVIRONMENT

WITH MLCAPE OF 2000-3000 J/KG COUPLED WITH VERY WIND PROFILES WITH

HEIGHT AND EFFECTIVE BULK SHEAR OF 30-40 KT ALSO WILL SUPPORT

MESOCYCLONE DEVELOPMENT AND POTENTIAL FOR LARGE HAIL.  STORMS ARE

EXPECTED TO PROGRESS EWD AND SEWD THIS EVENING WITH CONTINUED SEVERE

THREAT.



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 27030.





...WEISS

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