

000 

WWUS20 KWNS 072126

SEL0

SPC WW 072126

IAZ000-KSZ000-NEZ000-080500-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 480

NWS STORM PREDICTION CENTER NORMAN OK

425 PM CDT SAT JUN 7 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       A LARGE PART OF WESTERN IOWA

       PARTS OF NORTHERN KANSAS

       A LARGE PART OF EASTERN NEBRASKA



EFFECTIVE THIS SATURDAY AFTERNOON FROM 425 PM UNTIL MIDNIGHT CDT.



TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 75 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 20 MILES EAST OF DENISON

IOWA TO 65 MILES SOUTH SOUTHWEST OF KEARNEY NEBRASKA.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU0).



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 478...WW 479...



DISCUSSION...VERY TO EXTREMELY UNSTABLE AIR MASS WITH MLCAPES TO

3500 J/KG AND STRONG DEEP LAYER SHEAR AVAILABLE FOR SUPERCELL

DEVELOPMENT ACROSS THE WATCH AREA.  STORMS WILL DEVELOP RAPIDLY

ALONG WARM FRONT FROM NRN KS INTO WRN IA.  ALONG WITH VERY LARGE

HAIL...DAMAGING DOWNBURST WINDS...TORNADOES WILL BE LIKELY WITH ANY

SUPERCELL. STORMS EXPECTED TO DEVELOP UPSCALE DURING THE EVENING

INTO ONE OR MORE MCS/S.



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

SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

600. MEAN STORM MOTION VECTOR 24035.





...HALES

