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919 

WWUS20 KWNS 112313

SEL7

SPC WW 112313

NEZ000-120500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 457

NWS STORM PREDICTION CENTER NORMAN OK

615 PM CDT SUN JUL 11 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL NEBRASKA



EFFECTIVE THIS SUNDAY NIGHT FROM 615 PM UNTIL MIDNIGHT 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 65

STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH

NORTHEAST OF AINSWORTH NEBRASKA TO 45 MILES WEST SOUTHWEST OF

KEARNEY NEBRASKA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU7).



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 452...WW 453...WW

454...WW 455...WW 456...



DISCUSSION...SCATTERED THUNDERSTORMS WILL CONTINUE TO DEVELOP IN A

MODERATELY UNSTABLE ENVIRONMENT ACROSS CENTRAL NEB...DOWNSTREAM FROM

A SUBTLE MIDLEVEL VORTICITY CENTER MOVING ESEWD OVER NW NEB.

DESPITE NLY/NELY SURFACE WINDS ACROSS CENTRAL NEB...DEEP-LAYER

VERTICAL SHEAR REMAINS FAVORABLE FOR SUPERCELLS CAPABLE OF PRODUCING

LARGE HAIL AND DAMAGING WINDS IN THE STEEP LAPSE RATE PROFILES.



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 29030.





...THOMPSON

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