

000 

WWUS20 KWNS 252057

SEL0

SPC WW 252057

COZ000-NEZ000-WYZ000-260300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 750

NWS STORM PREDICTION CENTER NORMAN OK

255 PM MDT FRI JUL 25 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTH CENTRAL AND NORTHEAST COLORADO

       NEBRASKA PANHANDLE

       SOUTHEAST AND EAST CENTRAL WYOMING



EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 255 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 75

STATUTE MILES EAST AND WEST OF A LINE FROM 45 MILES WEST

SOUTHWEST OF AKRON COLORADO TO 50 MILES EAST NORTHEAST OF DOUGLAS

WYOMING.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0).



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 749...



DISCUSSION...THUNDERSTORMS ARE EXPECTED TO CONTINUE DEVELOPING THIS

AFTERNOON WITHIN MOIST LOW LEVEL UPSLOPE FLOW /20-25 KT SELY WINDS

ON KFTG VAD PROFILE/ REGIME OVER NRN CO AND SERN WY.  STEEP LAPSE

RATES COUPLED WITH SURFACE DEW POINTS IN THE 50S ARE CONTRIBUTING TO

MLCAPE OF 1000-1500 J/KG.  ALTHOUGH WINDS WEAKEN IN THE 2-4 KM AGL

LAYER...STRONG DIRECTIONAL SHEAR AND WINDS STRENGTHENING TO 30-40 KT

ABOVE 5-6 KM AGL ARE RESULTING IN DEEP LAYER SHEAR SUPPORTIVE OF

SEVERE THUNDERSTORMS INCLUDING ISOLATED SUPERCELLS.  ACTIVITY IS

EXPECTED TO GRADUALLY PROPAGATE WITH AN ELY COMPONENT INTO THE

INCREASING MOISTURE FIELD EAST OF THE FRONT RANGE.



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 450. MEAN STORM

MOTION VECTOR 26020.





...WEISS

