SPC Severe Thunderstorm Watch 649

WW 649 SEVERE TSTM KS MO 252250Z – 260400Z


URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 649
NWS STORM PREDICTION CENTER NORMAN OK
550 PM CDT TUE SEP 25 2012

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

       SOUTHEAST KANSAS
       SOUTHWEST AND CENTRAL MISSOURI

EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 550 PM UNTIL
1100 PM 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 25
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 90 MILES WEST OF
CHANUTE KANSAS TO 30 MILES SOUTHEAST OF VICHY MISSOURI.  FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU9).

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 648...

DISCUSSION...A BROKEN BAND OF STORMS WILL LIKELY INCREASE IN
COVERAGE THIS EVENING...ALONG THE INSTABILITY GRADIENT AND A WEAK
SURFACE BOUNDARY.  DEEP-LAYER VERTICAL SHEAR SUPPORTS PRIMARILY
MULTICELL STORMS...BUT THE STEEP LAPSE RATES/MODERATE CAPE WILL
FAVOR BOTH LARGE HAIL PRODUCTION IN THE STRONGEST UPDRAFTS...AS WELL
AS THE RISK FOR DAMAGING DOWNBURSTS/OUTFLOW FOR THE NEXT FEW HOURS.

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 550. MEAN STORM
MOTION VECTOR 28020.


...THOMPSON

via SPC Forecast Products http://www.spc.noaa.gov/products/watch/ww0649.html