SPC Severe Thunderstorm Watch 284

WW 284 SEVERE TSTM KS OK TX 200205Z – 200900Z


URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 284
NWS STORM PREDICTION CENTER NORMAN OK
905 PM CDT SAT MAY 19 2012

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

       SOUTH-CENTRAL AND SOUTHEAST KANSAS
       NORTHERN AND WESTERN OKLAHOMA
       NORTHWEST TEXAS

EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 905 PM
UNTIL 400 AM CDT.

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 60
STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES NORTHWEST OF
CHANUTE KANSAS TO 35 MILES SOUTH SOUTHEAST OF ALTUS OKLAHOMA.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU4).

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 281...WW 282...WW 283...

DISCUSSION...TWO SEPARATE CLUSTERS OF SEVERE STORMS ARE
ONGOING...ONE OVER W-CNTRL OK...AND THE OTHER OVER S-CNTRL KS...WITH
ADDITIONAL STORM FORMATION NOTED ALONG THE COLD FRONT ACROSS N-CNTRL
OK.  00Z OUN SOUNDING SHOWED THE PRESENCE OF A STRONG CAP WHICH
SHOULD LIMIT STORM DEVELOPMENT AND SUSTENANCE TO IMMEDIATE VICINITY
OF THE COLD FRONT.  GIVEN THE PRESENCE OF A MODESTLY MOIST...STEEP
LAPSE RATE THERMODYNAMIC ENVIRONMENT AND AROUND 40 KT OF EFFECTIVE
BULK SHEAR...SETUP WILL REMAIN SUPPORTIVE OF ORGANIZED
STORMS...INCLUDING SUPERCELLS AND BOWING STRUCTURES CAPABLE OF LARGE
HAIL AND DAMAGING WIND GUSTS.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 27025.


...MEAD

via SPC Forecast Products http://www.spc.noaa.gov/products/watch/ww0284.html