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WWUS20 KWNS 101035

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URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 1

NWS STORM PREDICTION CENTER NORMAN OK

435 AM CST THU JAN 10 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       CENTRAL LOUISIANA

       SOUTHWEST MISSISSIPPI

       COASTAL WATERS



EFFECTIVE THIS THURSDAY MORNING FROM 435 AM UNTIL NOON CST.



TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 45 STATUTE

MILES EAST AND WEST OF A LINE FROM 10 MILES NORTH OF NATCHEZ

MISSISSIPPI TO 40 MILES SOUTH SOUTHEAST OF INTRACOASTAL CITY

LOUISIANA.  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...EXISTING SSW-NNE SQLN HAS SHOWN SOME SIGNS OF

PERSISTENT STRENGTHENING IN THE PAST HOUR. THIS MAY BE DUE TO /1/

ARRIVAL OF DEEPER/STRONGER LOW-LVL WLY FLOW TO ITS LEADING EDGE /PER

LCH VWP/...AND /2/ TO PERHAPS INCREASED LARGE SCALE ASCENT NEARING

REGION /PER WATER VAPOR IMAGERY./ AT ANY RATE...AREA VWP DATA SHOW

AMPLE LOW-LVL SHEAR TO SUPPORT LOW-LVL MESO/POSSIBLE TORNADOES GIVEN

PERSISTENT ESELY SFC WINDS E OF SQLN LINE. ALSO...REGION IS

SUFFICIENTLY MOIST /DEWPOINTS IN THE UPR 60S TO AROUND 70F/ TO

SUPPORT SUSTAINED UPDRAFTS...DESPITE RELATIVELY WEAK MID-LVL LAPSE

RATES....GIVEN PRESENCE OF A SOURCE FOR LOW-LVL UPLIFT ALONG SQLN

GUST FRONT.

OVERALL SETUP SUGGESTS A POSSIBLY INCREASING RISK FOR EMBEDDED

LEWPS/ROTATING STRUCTURES CAPABLE OF TORNADOES/LOCALLY DMGG WIND AS

THE SQLN DEVELOPS FARTHER NNEWD...AND MOVES GENERALLY

ENEWD...THROUGH LATER THIS MORNING.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

400. MEAN STORM MOTION VECTOR 21030.





...CORFIDI

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