

000 

WWUS20 KWNS 311805

SEL2

SPC WW 311805

COZ000-KSZ000-NEZ000-010100-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 312

NWS STORM PREDICTION CENTER NORMAN OK

1205 PM MDT THU MAY 31 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       EASTERN COLORADO

       WESTERN KANSAS

       SOUTHWEST NEBRASKA



EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 1205 PM UNTIL

700 PM MDT.



TORNADOES...HAIL TO 2 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 135 STATUTE

MILES EAST AND WEST OF A LINE FROM 15 MILES NORTHEAST OF IMPERIAL

NEBRASKA TO 75 MILES SOUTH SOUTHEAST OF BURLINGTON COLORADO.  FOR

A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU2).



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.



DISCUSSION...STRONG/SEVERE STORMS CONTINUE IN ALLEY OF FAVORABLE

MOISTURE CONVERGENCE AS A MID/UPPER LEVEL SHORTWAVE TROUGH BEGINS TO

MOVE SEWD FROM SERN WY.  AIR MASS CONTINUES TO DESTABILIZE AS MUCAPE

VALUES ARE BETWEEN 100-2000 J/KG.  DEEP LAYER IS ALSO ON THE

INCREASE AT 50-60 KT FROM CENTRAL CO INTO W CENTRAL KS JUST AHEAD OF

MID LEVEL JET EXIT REGION.  EXPECT MORE STORM DEVELOPMENT NEXT

SEVERAL HOURS ACROSS THIS AREA AHEAD OF SHORTWAVE TROUGH/MID LEVEL

JET EXIT REGION AS AIR MASS CONTINUES TO DESTABILIZE AND LOW LEVEL

JET BECOMES MORE DEFINED BETWEEN NOW AND 00Z.



AVIATION...TORNADOES AND 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

450. MEAN STORM MOTION VECTOR 27030.





...MCCARTHY

