

477 

WWUS20 KWNS 202202

SEL7

SPC WW 202202

COZ000-NEZ000-SDZ000-WYZ000-210500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 427

NWS STORM PREDICTION CENTER NORMAN OK

405 PM MDT SAT JUL 20 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  NORTHEAST COLORADO

  WESTERN AND NORTHERN NEBRASKA

  WESTERN SOUTH DAKOTA

  EASTERN WYOMING



* EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 405 PM UNTIL

  1100 PM MDT.



* PRIMARY THREATS INCLUDE...

  SEVERAL LARGE HAIL EVENTS WITH A FEW VERY LARGE HAIL EVENTS TO

    2.5 INCHES IN DIAMETER POSSIBLE

  SEVERAL DAMAGING WIND GUSTS TO 70 MPH POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 80

STATUTE MILES EAST AND WEST OF A LINE FROM 60 MILES EAST

NORTHEAST OF BUFFALO SOUTH DAKOTA TO 45 MILES SOUTH SOUTHWEST OF

AKRON COLORADO.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU7).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



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 425...WW 426...



DISCUSSION...SCATTERED THUNDERSTORMS ARE INCREASING IN COVERAGE OVER

THE NORTHERN HIGH PLAINS THIS EVENING.  SUFFICIENT WINDS ALOFT

COUPLED WITH MODERATE INSTABILITY WILL PROMOTE ORGANIZED/SUPERCELL

THUNDERSTORMS CAPABLE OF LARGE HAIL AND DAMAGING WINDS THROUGH MUCH

OF THE EVENING.



AVIATION...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.





...HART

