URGENT – IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 1
NWS STORM PREDICTION CENTER NORMAN OK
315 PM CST WED JAN 20 2010
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
PARTS OF LOUISIANA
SOUTHWEST MISSISSIPPI
SOUTHEAST TEXAS
EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 315 PM UNTIL
1000 PM CST.
TORNADOES…HAIL TO 1.5 INCHES IN DIAMETER…THUNDERSTORM WIND
GUSTS TO 70 MPH…AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 80 MILES WEST OF FORT POLK
LOUISIANA TO 60 MILES EAST OF MC COMB MISSISSIPPI. FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU1).
REMEMBER…A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND 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.
DISCUSSION…TSTMS SHOULD CONTINUE TO INCREASE IN COVERAGE AND
INTENSITY THIS AFTERNOON INTO EVENING…DRIVEN BY BROAD LOW-LEVEL
WAA REGIME. AMBIENT AIR MASS HAS BECOME WARM…MOIST AND MODERATELY
UNSTABLE WITH MLCAPE OF 1000-2000 J/KG. WHEN COUPLED WITH 40-45 KT
OF DEEP-LAYER LAYER AND STEADILY STRENGTHENING LOW-LEVEL SHEAR ALONG
LLJ AXIS…ENVIRONMENT WILL FAVOR THE DEVELOPMENT OF SUPERCELLS
CAPABLE OF A FEW TORNADOES…IN ADDITION TO HAIL AND LOCALLY
DAMAGING WIND GUSTS.
AVIATION…TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
450. MEAN STORM MOTION VECTOR 24035.
