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298 

WWUS20 KWNS 210445

SEL3

SPC WW 210445

KSZ000-NEZ000-211100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 363

NWS STORM PREDICTION CENTER NORMAN OK

1145 PM CDT SUN JUN 20 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHWESTERN KANSAS

       SOUTHERN AND CENTRAL NEBRASKA



EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 1145 PM UNTIL

600 AM CDT.



HAIL TO 2.5 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 70

STATUTE MILES EITHER SIDE OF A LINE FROM 25 MILES WEST NORTHWEST

OF IMPERIAL NEBRASKA TO 5 MILES EAST SOUTHEAST OF GRAND ISLAND

NEBRASKA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3).



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 360...WW 361...WW 362...



DISCUSSION...LOW LEVEL JET LIFTING NWD OVER BOUNDARY IN NRN KS

SHOULD AID IN ELEVATED THUNDERSTORMS INCREASING OVER PORTIONS OF

NWRN KS AND SOUTHERN/CENTRAL NEB. ALTHOUGH THE UPDRAFT ROOTS ARE

EXPECTED TO BE LOCATED BETWEEN 700-850 MB...THE COMBINATION OF STEEP

LAPSE RATES...MUCAPES RANGING 2000 AND 3000 J/KG AND 30-40 KT OF

SHEAR IN THE CLOUD BEARING LAYER SHOULD BE SUFFICIENT FOR SEVERE

STORMS WITH LARGE HAIL.



AVIATION...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 500. MEAN STORM

MOTION VECTOR 23020.





...IMY

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