URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 49
NWS STORM PREDICTION CENTER NORMAN OK
150 PM CST SAT MAR 9 2013

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

SOUTHERN OKLAHOMA
CENTRAL AND NORTH TEXAS

EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 150 PM UNTIL
1100 PM CST.

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 70
STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES SOUTH OF
BROWNWOOD TEXAS TO 35 MILES NORTH NORTHEAST OF ARDMORE OKLAHOMA.
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...BAND OF TSTMS INVOF SFC COLD FRONT IS INCREASING
GRADUALLY IN INTENSITY AND ORGANIZATION AS FRONTAL ZONE IMPINGES
UPON PROGRESSIVELY MORE MOIST BOUNDARY LAYER...DESTABILIZED BY
NARROW CORRIDOR OF PREFRONTAL SFC DIABATIC HEATING. FAVORABLE DEEP
SHEAR AND BUOYANCY ARE FCST FOR CONTINUED TSTM ORGANIZATION AND SVR
POTENTIAL INTO AT LEAST EARLY EVENING. QUASI-LINEAR MODE SHOULD
PREDOMINATE WITH BOW/LEWP FORMATIONS OFFERING THREAT OF DAMAGING
GUSTS AND MRGL HAIL. ANY SUSTAINED SUPERCELLS THAT CAN FORM WITHIN
OR AHEAD OF LINE WILL POSE RISK OF LARGER HAIL AND A TORNADO...BUT
THIS THREAT IS MORE CONDITIONAL.

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 450. MEAN STORM
MOTION VECTOR 23035.


...EDWARDS