Severe Thunderstorm Watch #239

URGENT – IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 239
NWS STORM PREDICTION CENTER NORMAN OK
605 PM CDT SAT APR 26 2008

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

CENTRAL AND WEST CENTRAL TEXAS

EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 605 PM
UNTIL 100 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 75
STATUTE MILES EAST AND WEST OF A LINE FROM 55 MILES EAST
NORTHEAST OF LUBBOCK TEXAS TO 55 MILES SOUTH OF JUNCTION TEXAS.
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.

DISCUSSION…THUNDERSTORMS ARE DEVELOPING ALONG A WARM FRONT ALONG
THE CORRIDOR FROM JCT TO SJT IN RESPONSE TO LOW-LEVEL CONVERGENCE
AND STRONG DAYTIME HEATING. OTHER CONVECTION IS COALESCING OVER THE
SOUTH PLAINS IN ADVANCE OF A STRONG MID LEVEL TROUGH MOVING ESEWD
FROM NM AND NRN TX PANHANDLE. LOW-LEVEL MOISTURE IS LIMITED ACROSS
MUCH OF W TX…BUT STEEP LAPSE RATES ARE STILL SUPPORTING SUFFICIENT
INSTABILITY FOR SEVERE STORMS. DAMAGING WINDS SHOULD BE THE PRIMARY
SEVERE THREAT WITH THE SOUTH PLAINS CONVECTION AS IT ORGANIZES AND
SPREADS SEWD/SSEWD ALONG THE RESIDUAL WARM FRONT. FARTHER S…THE
MORE DISCRETE STORMS SHOULD DEVELOP INTO SPLITTING SUPERCELLS
STRUCTURES WITH THE THREAT FOR LARGE HAIL AND DAMAGING WINDS.

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 31025.

…THOMPSON