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URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 281

NWS STORM PREDICTION CENTER NORMAN OK

335 PM MDT MON JUN 7 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       EXTREME NORTH CENTRAL AND NORTHEAST COLORADO

       THE NEBRASKA PANHANDLE

       EXTREME SOUTHWEST SOUTH DAKOTA

       EAST CENTRAL AND SOUTHEAST WYOMING



EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 335 PM UNTIL

1100 PM MDT.



TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 65 STATUTE

MILES EAST AND WEST OF A LINE FROM 65 MILES NORTHEAST OF DOUGLAS

WYOMING TO 50 MILES SOUTHWEST OF SIDNEY NEBRASKA.  FOR A COMPLETE

DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE

(WOUS64 KWNS WOU1).



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 280...



DISCUSSION...THUNDERSTORMS WILL LIKELY INCREASE IN

COVERAGE/INTENSITY THROUGH THE AFTERNOON/EVENING ACROSS E/SE WY AS

60+ BOUNDARY LAYER DEWPOINTS SPREAD WWD/NWWD INTO SE WY.  EROSION OF

THE EARLIER CLOUDS WILL RESULT IN WEAKENING OF THE CAP FARTHER E

WITH TIME...AND THERE WILL BE SOME POTENTIAL FOR UPSCALE GROWTH OF

INITIAL STORMS INTO AN MCS BY EARLY TONIGHT IN WRN NEB.  THE

COMBINATION OF MODERATE INSTABILITY WITH STRONG DEEP-LAYER SHEAR

WILL SUPPORT SUPERCELLS FOR THE FIRST SEVERAL HOURS AFTER

INITIATION.  ISOLATED VERY LARGE HAIL AND DAMAGING WINDS CAN BE

EXPECTED WITH THE SUPERCELLS.  ADDITIONALLY...A FEW TORNADOES WILL

BE POSSIBLE GIVEN THE RICH BOUNDARY LAYER MOISTURE AND MODEST

LOW-LEVEL SHEAR.  LATER THIS EVENING...THE PRIMARY THREATS WILL

TRANSITION TO DAMAGING WINDS AND LARGE HAIL.



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

500. MEAN STORM MOTION VECTOR 29030.





...THOMPSON

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