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WWUS20 KWNS 220346

SEL9

SPC WW 220346

IAZ000-MOZ000-NEZ000-220800-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 669

NWS STORM PREDICTION CENTER NORMAN OK

1045 PM CDT THU JUL 21 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       FAR SOUTHWEST IOWA

       FAR NORTHWEST MISSOURI

       SOUTHEAST NEBRASKA



EFFECTIVE THIS THURSDAY NIGHT AND FRIDAY MORNING FROM 1045 PM

UNTIL 300 AM CDT.



HAIL TO 1 INCH 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 50

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 40 MILES SOUTHWEST

OF KEARNEY NEBRASKA TO 20 MILES EAST NORTHEAST OF SHENANDOAH

IOWA.  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 668...



DISCUSSION...CLUSTERS OF STRONG/SVR TSTMS EXPECTED TO CONTINUE

MOVING/DEVELOPING MAINLY ENE ALONG AND N OF FRONT/OUTFLOW BOUNDARY

STALLED ALONG THE NEB/KS BORDER.  STRENGTHENING LLJ AND AVAILABILITY

OF RICH MOISTURE ALONG AND N OF BOUNDARY SUGGEST CONTINUED POTENTIAL

FOR ISOLD DMGG WIND GUSTS AND POSSIBLY MARGINALLY SVR HAIL.



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

TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS.

A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM MOTION

VECTOR 25020.





...CORFIDI

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