SPC Severe Thunderstorm Watch 312

WW 312 SEVERE TSTM KS NE 142000Z – 150200Z


URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 312
NWS STORM PREDICTION CENTER NORMAN OK
300 PM CDT FRI JUN 14 2013

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
  A SMALL PART OF NORTHWEST AND NORTH CENTRAL KANSAS
  SOUTH CENTRAL NEBRASKA

* EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 300 PM UNTIL
  900 PM CDT.

* PRIMARY THREATS INCLUDE...
  A FEW DAMAGING WIND GUSTS TO 70 MPH POSSIBLE
  A FEW LARGE HAIL EVENTS TO 1.5 INCHES IN DIAMETER POSSIBLE

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 35
STATUTE MILES EITHER SIDE OF A LINE FROM 40 MILES SOUTH OF MCCOOK
NEBRASKA TO 20 MILES EAST NORTHEAST OF GRAND ISLAND NEBRASKA.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU2).

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...CONVECTION IS DEVELOPING NEWD ALONG THE SURFACE COLD
FRONT AS LOW-LEVEL LAPSE RATES STEEPEN AND CONVECTIVE INHIBITION IS
REMOVED.  THE INITIAL HIGH-BASED STORMS WILL POSE A RISK FOR
ISOLATED DAMAGING DOWNBURSTS...THOUGH THE RISK FOR ISOLATED LARGE
HAIL SHOULD INCREASE SOME AS THE STORMS WILL SPREAD INTO A
PROGRESSIVELY MORE UNSTABLE ENVIRONMENT WITH NEWD EXTENT IN NEB.
THE COMBINATION OF MODERATE-STRONG INSTABILITY AND MODEST VERTICAL
SHEAR WILL SUPPORT MULTICELL CLUSTERS AS THE PRIMARY CONVECTIVE
MODE.

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 500. MEAN STORM
MOTION VECTOR 24020.


...THOMPSON

via SPC Forecast Products http://www.spc.noaa.gov/products/watch/ww0312.html