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WWUS20 KWNS 030550

SEL8

SPC WW 030550

IAZ000-MOZ000-NEZ000-031000-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 228

NWS STORM PREDICTION CENTER NORMAN OK

1250 AM CDT THU MAY 3 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHWEST IOWA

       NORTHWEST MISSOURI

       SOUTHEAST NEBRASKA



EFFECTIVE THIS THURSDAY MORNING FROM 1250 AM UNTIL 500 AM CDT.



HAIL TO 1.5 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 EAST AND WEST OF A LINE FROM 45 MILES SOUTH

SOUTHWEST OF SHENANDOAH IOWA TO 35 MILES NORTH NORTHWEST OF

SHENANDOAH IOWA.  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 226...WW 227...



DISCUSSION...A CLUSTER OF INTENSE THUNDERSTORMS OVER SOUTHEAST NEB

HAS RECENTLY SHOWN SIGNS OF GROWING UPSCALE AND SURGING EASTWARD

ALONG THE INSTABILITY AXIS.  IF THIS OCCURS...DAMAGING WINDS WILL

BECOME A GREATER THREAT ACROSS THE WATCH AREA.  LARGE HAIL WILL ALSO

BE POSSIBLE IN THE STRONGER CORES.



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

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 27030.





...HART

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