

813 

WWUS20 KWNS 082100

SEL0

SPC WW 082100

NEZ000-SDZ000-090200-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 400

NWS STORM PREDICTION CENTER NORMAN OK

400 PM CDT MON JUL 8 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  NORTH CENTRAL NEBRASKA

  SOUTH CENTRAL SOUTH DAKOTA



* EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 400 PM UNTIL

  900 PM CDT.



* PRIMARY THREATS INCLUDE...

  SEVERAL DAMAGING WIND GUSTS TO 70 MPH LIKELY

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

    2.5 INCHES IN DIAMETER POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 80

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 85 MILES WEST

NORTHWEST OF MULLEN NEBRASKA TO 35 MILES NORTH NORTHEAST OF

ONEILL NEBRASKA.  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.



&&



OTHER WATCH INFORMATION...CONTINUE...WW 398...WW 399...



DISCUSSION...THUNDERSTORMS ARE EXPECTED TO FORM SOON OVER NORTH

CENTRAL NEB AND SOUTH CENTRAL SD...SPREADING EASTWARD ACROSS THE

WATCH AREA THROUGH THE EARLY EVENING HOURS.  STRONG INSTABILITY

COUPLED WITH SUFFICIENT VERTICAL SHEAR WILL PROMOTE ORGANIZED

MULTICELL TO SUPERCELL STORMS CAPABLE OF LARGE HAIL AND DAMAGING

WINDS.  STORMS WILL LIKELY ORGANIZE INTO BOWING SEGMENTS THIS

EVENING AS THEY TRACK ACROSS THE WATCH.



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 27030.





...HART

