

737 

WWUS20 KWNS 232050

SEL2

SPC WW 232050

COZ000-NEZ000-WYZ000-240300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 502

NWS STORM PREDICTION CENTER NORMAN OK

250 PM MDT TUE JUN 23 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTH CENTRAL AND NORTHEAST COLORADO

       NEBRASKA PANHANDLE

       SOUTHEAST WYOMING



EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 250 PM UNTIL

900 PM 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 60

STATUTE MILES EAST AND WEST OF A LINE FROM 35 MILES NORTH

NORTHEAST OF TORRINGTON WYOMING TO 5 MILES SOUTH SOUTHWEST OF

LIMON COLORADO.  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 497...WW 498...WW

499...WW 500...WW 501...



DISCUSSION...THUNDERSTORMS WILL CONTINUE INCREASING AHEAD OF SUBTLE

IMPULSE ROTATING ACROSS THE CENTRAL ROCKIES THIS AFTERNOON...WITH

ACTIVITY SHIFTING OVER LOWER ELEVATIONS THROUGH THE EVENING.  MOIST

AND UNSTABLE AIR MASS ALONG AND EAST OF THE FRONT RANGE SHOULD

FOSTER POTENTIAL FOR SEVERE THUNDERSTORMS...INCLUDING A SUPERCELL OR

TWO.  LARGE HAIL AND DAMAGING WINDS WILL BE PRIMARY

THREATS...ALTHOUGH A BRIEF TORNADO CAN NOT BE RULED OUT.



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 24020.





...EVANS

