

383 

WWUS20 KWNS 152331

SEL8

SPC WW 152331

ILZ000-KSZ000-MOZ000-160600-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 308

NWS STORM PREDICTION CENTER NORMAN OK

630 PM CDT FRI MAY 15 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       EXTREME SOUTHWEST ILLINOIS

       EXTREME EASTERN KANSAS

       PARTS OF CENTRAL AND SOUTHERN MISSOURI



EFFECTIVE THIS FRIDAY NIGHT AND SATURDAY MORNING FROM 630 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 55

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 55 MILES SOUTH

SOUTHWEST OF OLATHE KANSAS TO 25 MILES NORTHEAST OF FARMINGTON

MISSOURI.  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 305...WW 306...WW 307...



DISCUSSION...AN E-W OUTFLOW BOUNDARY WILL CONTINUE TO SAG SWD ACROSS

CENTRAL MO IN RESPONSE TO REINFORCEMENT OF THE COLD POOL WITH

REPEATED/TRAINING CONVECTION...AND THE COLD FRONTAL STORMS IN ERN KS

WILL ALSO SPREAD EWD/SEWD INTO SE KS AND W/SW MO THROUGH LATE

EVENING.  THE STORMS WILL BE MAINTAINED BY A FEED OF MODERATE/STRONG

INSTABILITY FROM THE S/SW...WHILE THE CONVECTION WILL GRADUALLY SAG

S OF THE STRONGER BELT OF MID-UPPER FLOW.  THESE FACTORS...ALONG

WITH THE ONGOING LARGELY LINEAR CONVECTIVE MODE...SUGGEST THAT LARGE

HAIL AND DAMAGING WINDS WITH EMBEDDED STRONGER CELLS/BOWS WILL BE

THE PRIMARY SEVERE THREATS.



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 28030.





...THOMPSON

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