SPC Severe Thunderstorm Watch 234

WW 234 SEVERE TSTM KS OK TX 281955Z – 290300Z


URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 234
NWS STORM PREDICTION CENTER NORMAN OK
255 PM CDT TUE MAY 28 2013

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
  SOUTHWEST KANSAS
  NORTHWEST OKLAHOMA INCLUDING THE PANHANDLE
  WEST TEXAS INCLUDING THE PANHANDLE

* EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 255 PM UNTIL
  1000 PM CDT.

* PRIMARY THREATS INCLUDE...
  SEVERAL VERY LARGE HAIL EVENTS TO 2.5 INCHES IN DIAMETER
    POSSIBLE
  SEVERAL DAMAGING WIND GUSTS TO 70 MPH POSSIBLE
  A FEW TORNADOES POSSIBLE

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 60
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 80 MILES WEST
SOUTHWEST OF AMARILLO TEXAS TO 30 MILES NORTH NORTHEAST OF
MEDICINE LODGE KANSAS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE
THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).

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 233...

DISCUSSION...TSTMS ARE EXPECTED TO INCREASE IN COVERAGE AND
INTENSITY THIS AFTERNOON ALONG RETREATING DRYLINE IN RESPONSE TO
STRENGTHENING LARGE-SCALE FORCING ATTENDANT TO A SHORT-WAVE TROUGH
MOVING INTO THE HIGH PLAINS.  THE 18Z AMA SOUNDING SHOWED THE
PRESENCE OF VERY STEEP LAPSE RATES AND INCREASING LOW-LEVEL
MOISTURE...YIELDING A MODERATELY UNSTABLE AIR MASS.  WHEN COUPLED
WITH A VERTICALLY VEERING WIND PROFILE WITH 35-45 KT OF DEEP-LAYER
SHEAR...THE SETUP WILL BE SUPPORTIVE OF SUPERCELLS CAPABLE OF VERY
LARGE HAIL AND DAMAGING WINDS.  INITIALLY...TORNADO POTENTIAL WILL
BE LIMITED BY THE HIGH LCL ENVIRONMENT.  THIS THREAT COULD INCREASE
THIS EVENING AS LOW-LEVEL MOISTURE CONTINUES TO INCREASE AND
LOW-LEVEL SHEAR STRENGTHENS...AND AN UPGRADE TO TORNADO MAY BECOME
NECESSARY.

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 26020.


...MEAD

via SPC Forecast Products http://www.spc.noaa.gov/products/watch/ww0234.html