

443 

WWUS20 KWNS 131921

SEL0

SPC WW 131921

IDZ000-NVZ000-140200-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 460

NWS STORM PREDICTION CENTER NORMAN OK

125 PM MDT WED AUG 13 2014



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  SOUTHWEST AND SOUTH CENTRAL IDAHO

  NORTHEAST NEVADA



* EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 125 PM

  UNTIL 800 PM MDT.



* PRIMARY THREATS INCLUDE...

  ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

  ISOLATED LARGE HAIL EVENTS TO 1.5 INCHES IN DIAMETER POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 45

STATUTE MILES EAST AND WEST OF A LINE FROM 50 MILES NORTHWEST OF

HAILEY IDAHO TO 65 MILES SOUTHEAST OF ELKO NEVADA.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU0).



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.



&&



DISCUSSION...SCATTERED THUNDERSTORMS WILL CONTINUE TO STRENGTHEN

THIS AFTERNOON AND SPREAD FROM NE NV INTO SW/S CENTRAL ID AS THE LOW

LEVELS DESTABILIZE.  MODIFIED 18Z BOI SOUNDING SUGGESTS MLCAPE NEAR

1000 J/KG AND EFFECTIVE BULK SHEAR OF 35-45 KT...WHICH WILL BE

SUFFICIENT FOR ORGANIZED/SUPERCELL STORMS CAPABLE OF PRODUCING

DAMAGING GUSTS AND LARGE HAIL.



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

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM

MOTION VECTOR 21025.





...THOMPSON

