

583 

WWUS20 KWNS 092046

SEL8

SPC WW 092046

COZ000-KSZ000-NEZ000-WYZ000-100300-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 288

NWS STORM PREDICTION CENTER NORMAN OK

240 PM MDT WED JUN 9 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       NORTHEASTERN COLORADO

       EXTREME NORTHWESTERN KANSAS

       WESTERN NEBRASKA

       SOUTHEASTERN WYOMING



EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 240 PM UNTIL

900 PM MDT.



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 80 STATUTE

MILES EAST AND WEST OF A LINE FROM 25 MILES NORTH NORTHWEST OF

ALLIANCE NEBRASKA TO 10 MILES SOUTHWEST OF LIMON COLORADO.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU8).



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 286...WW 287...



DISCUSSION...THUNDERSTORMS HAVE RECENTLY DEVELOPED FROM WESTERN NEB

SWWD INTO THE NRN CO MOUNTAINS. VERY MOIST UPSLOPE FLOW...WITH

DEWPOINTS NEAR 60F TO NEAR THE FOOTHILLS...SHOULD BE FAVORABLE FOR

MORE STORMS FORMING THROUGH THE EVENING HOURS. THE COMBINATION OF

MODERATE INSTABILITY AND EFFECTIVE SHEAR NEAR 50 KT WILL BE

FAVORABLE FOR SUPERCELLS WITH VERY LARGE HAIL. TORNADOES ARE ALSO

POSSIBLE...ESPECIALLY ACROSS WRN NEB WHERE BOUNDARY LAYER RH VALUES

ARE HIGHER AND LOW LEVEL SHEAR IS MAXIMIZED. ALSO...ANY STORMS THAT

TURN SEWD WOULD INGEST GREATER SRH AND POSSESS A POTENTIAL FOR A

TORNADO.



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

500. MEAN STORM MOTION VECTOR 28020.





...IMY

