

687 

WWUS20 KWNS 151245

SEL4

SPC WW 151245

IAZ000-KSZ000-MOZ000-NEZ000-152000-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 304

NWS STORM PREDICTION CENTER NORMAN OK

745 AM CDT FRI MAY 15 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHWEST IOWA

       NORTHEAST KANSAS

       NORTHERN AND WEST CENTRAL MISSOURI

       SOUTHEAST NEBRASKA



EFFECTIVE THIS FRIDAY MORNING AND AFTERNOON FROM 745 AM UNTIL 300

PM 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 155

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

NORTHWEST OF SHENANDOAH IOWA TO 15 MILES SOUTH SOUTHWEST OF

OLATHE KANSAS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).



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...SCTD STRONG ELEVATED TSTMS HAVE BEEN FORMING OVER N

CNTRL KS IN THE PAST 2 HRS IN WAKE OF WEAKER EARLIER STORMS NOW OVER

NRN MO.  THE KS STORMS APPEAR TO BE ASSOCIATED WITH LEADING EDGE OF

QUALITY MOISTURE RETURN /PER SATELLITE-DERIVED PW DATA/...AND

PERHAPS WEAK DPVA AHEAD OF MAIN NRN RCKYS UPR TROUGH.  COMBINATION

OF INCREASING MOISTURE INFLOW AND...WITH TIME...UPSTREAM DIURNAL

DESTABILIZATION...MAY SUPPORT STORM INTENSIFICATION AND ALLOW THE

ACTIVITY TO BECOME MORE NEARLY SFC-BASED.  THUS...A THREAT WILL

EXIST FOR SVR HAIL AND...WITH TIME...POSSIBLY DMGG WIND.



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 500. MEAN STORM

MOTION VECTOR 24035.





...CORFIDI

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