

956 

WWUS20 KWNS 050328

SEL2

SPC WW 050328

NEZ000-SDZ000-051000-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 662

NWS STORM PREDICTION CENTER NORMAN OK

930 PM MDT TUE AUG 4 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       LARGE PART OF CENTRAL NEBRASKA

       PARTS OF SOUTH CENTRAL SOUTH DAKOTA



EFFECTIVE THIS TUESDAY NIGHT AND WEDNESDAY MORNING FROM 930 PM

UNTIL 400 AM MDT.



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 70

STATUTE MILES EITHER SIDE OF A LINE FROM 60 MILES WEST NORTHWEST

OF VALENTINE NEBRASKA TO 15 MILES SOUTH OF BROKEN BOW NEBRASKA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU2).



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 660...WW 661...



DISCUSSION...SEVERE MCS OVER SWRN SD WILL CONTINUE AND TURN MORE

SEWD ALONG AXIS OF GREATEST INSTABILITY INTO CENTRAL NEB.  CONTINUED

THREAT OF LARGE HAIL AND DAMAGING WINDS AS EFFECTIVE SHEAR OF 35-40

KT AND MLCAPES AOA 1000 J/KG WILL SUPPORT SEVERE FOR SEVERAL MORE

HOURS.



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 31030.





...HALES

