

226 

WWUS20 KWNS 180036

SEL4

SPC WW 180036

COZ000-180400-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 784

NWS STORM PREDICTION CENTER NORMAN OK

635 PM MDT WED AUG 17 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHEAST COLORADO



EFFECTIVE THIS WEDNESDAY EVENING FROM 635 PM UNTIL 1000 PM MDT.



HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 75

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 55

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 35 MILES SOUTHWEST

OF LA JUNTA COLORADO TO 40 MILES EAST SOUTHEAST OF LAMAR

COLORADO.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).



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 783...



DISCUSSION...STORMS ARE BECOMING BETTER ORGANIZED INTO AN ARCING

LINE APPROACHING THE AR RIVER VALLEY AS CONVERGENCE INCREASES ALONG

INTERSECTING OUTFLOW BOUNDARIES.  MOIST UPSLOPE LOW LEVEL FLOW AND A

DEEP WELL-MIXED BOUNDARY LAYER WILL ENHANCE POTENTIAL FOR DAMAGING

WIND GUSTS AND OCCASIONAL HAIL AS THE LINE MOVES SEWD OVER THE NEXT

SEVERAL HOURS.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 65

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 29020.





...WEISS

