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WWUS20 KWNS 142043

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IAZ000-NEZ000-150300-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 313

NWS STORM PREDICTION CENTER NORMAN OK

340 PM CDT FRI JUN 14 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* TORNADO WATCH FOR PORTIONS OF

  EXTREME WESTERN IOWA

  EASTERN NEBRASKA



* EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 340 PM UNTIL

  1000 PM CDT.



* PRIMARY THREATS INCLUDE...

  SEVERAL TORNADOES POSSIBLE

  SEVERAL VERY LARGE HAIL EVENTS TO 2.5 INCHES IN DIAMETER

    POSSIBLE

  SEVERAL DAMAGING WIND GUSTS TO 70 MPH POSSIBLE



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 70 STATUTE

MILES EAST AND WEST OF A LINE FROM 40 MILES NORTH NORTHWEST OF

NORFOLK NEBRASKA TO 25 MILES SOUTHEAST OF LINCOLN NEBRASKA.  FOR

A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU3).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.



&&



OTHER WATCH INFORMATION...CONTINUE...WW 312...



DISCUSSION...THUNDERSTORMS IN S CENTRAL NEB WILL CONTINUE TO SPREAD

NEWD TOWARD NE NEB THIS AFTERNOON...WHERE ADDITIONAL SURFACE-BASED

DEVELOPMENT WILL BE POSSIBLE NEAR THE TRIPLE POINT.  THE ENVIRONMENT

FROM THE TRIPLE POINT SEWD ACROSS ERN NEB IS CHARACTERIZED BY

BOUNDARY LAYER DEWPOINTS NEAR 70 F AND SURFACE TEMPERATURES

APPROACHING 90 F FROM THE SW...WHICH WILL CONTINUE TO WEAKEN

CONVECTIVE INHIBITION AND SUPPORT NEW STORM DEVELOPMENT.

MEANWHILE...THE OAX VWP SHOWS A RELATIVELY LARGE CLOCKWISE TURNING

HODOGRAPH...WITH SUFFICIENT VERTICAL SHEAR FOR SUPERCELLS.  GIVEN

EFFECTIVE SRH NEAR 300 M2/S2...MLCAPE OF 3000-4000 J/KG...AND MLLCL

HEIGHTS NEAR 1250 M...A FEW TORNADOES AND ISOLATED VERY LARGE HAIL

WILL BE POSSIBLE WITH THE INITIALLY MORE DISCRETE STORMS.  LATER

THIS EVENING...SOME UPSCALE GROWTH IS EXPECTED INTO A SMALL

SEWD-MOVING MCS...WITH AN ATTENDANT RISK FOR DAMAGING GUSTS.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

550. MEAN STORM MOTION VECTOR 27020.





...THOMPSON

