Severe Thunderstorm Warning 62, NWS Lake Charles, LA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAKE CHARLES LA
429 PM CST WED DEC 29 2010

.DISCUSSION...
ELONGATED SHORTWAVE TROF EVIDENT KICKING EAST THROUGH EASTERN
OK/EASTERN TX PER LATEST WATER VAPOR IMAGERY.

AHEAD OF THIS FEATURE...RAINFALL WHICH HAD BEEN MOSTLY STRATIFORM
IN NATURE...IS BECOMING A LITTLE MORE CONVECTIVE/CELLULAR PER
LATEST RADAR IMAGERY...COINCIDENT WITH PROGGED INCREASE IN LIMITED
INSTABILITY. DECENT AMOUNT OF LIGHTING TO OUR WEST IN THE HOUSTON
AREA...BUT INSTABILITY IS NOT PROGGED TO GET AS HIGH THIS FAR
EAST. THUS...WILL MAINTAIN ISOLATED THUNDER MENTION WITH
PREVAILING SHOWERS.

POPS AND WEATHER WERE ADJUSTED SLIGHTLY TO ACCOUNT FOR LATEST
TRENDS/GUIDANCE...BUT THE PREVIOUS FORECAST CALLING FOR AN END TO
PRECIP BEFORE THURSDAY MORNING AS THE TROF AXIS PASSES TO THE EAST
IS STILL LARGELY ON TARGET. DESPITE VERY FAVORABLE DEEP LAYER
SHEAR AND LOW LEVEL HELICITY...THE LIMITED INSTABILITY IS EXPECTED
TO CONTINUE INHIBITING A MORE WIDESPREAD/SIGNIFICANT SEVERE
WEATHER THREAT...THOUGH A LOW END PROBABILITY WILL EXIST. THIS WAS
ALREADY ADDRESSED IN AN UPDATED HWO EARLIER THIS MORNING.

WITH PERSISTENT SOUTHERLY FETCH ADVECTING AIR CHARACTERIZED BY
DEWPOINTS IN THE MID 60S ATOP SSTS IN THE MID/UPPER 50S...THE
PROBABILITY OF SEA FOG FORMATION IS INCREASING. INSERTED PATCHY
FOG INTO THE SOUTHEAST TEXAS NEARSHORE WATERS THIS EVENING...EXPANDING
IT NORTH AND EAST OVERNIGHT INTO THURSDAY. ATTM I DID NOT INCLUDE
PAST NOON ON THURSDAY...BUT IT IS QUITE POSSIBLE THAT IF GOOD BANK
OF SEA FOG DEVELOPS...IT WILL PERSIST LONGER.

THURSDAY LOOKS TO BE SOMEWHAT OF A BREAK DAY AS THE CURRENT TROF
EXITS TO THE EAST AND A MORE POTENT UPSTREAM TROF DIGS INTO THE
WRN CONUS. STILL...WITH DECENT MOISTURE AND AN ACTIVE LL JET
REMAINING IN PLACE...AND THE LEAD SOUTHWESTERLY JET ASSOCIATED
WITH THIS UPSTREAM TROF STARTING TO IMPINGE ON THE AREA LATE
TOMORROW...CANNOT RULE OUT AT LEAST ISOLATED SHOWERS...SO THE
SMALL CHANCES WERE RETAINED.

SHOWER AND THUNDERSTORM CHANCES WILL BEGIN TO INCREASE AGAIN ON
FRIDAY AS THE TROF AND ITS ASSOCIATED FRONTAL SYSTEM DRAW CLOSER
TO THE REGION...WITH THE FRONT FORECAST TO MOVE THROUGH THE AREA
FRIDAY AFTERNOON AND NIGHT. KEEP YOUR UMBRELLA HANDY NEW YEARS EVE.

&&

.MARINE...
STRONG ONSHORE FLOW IS EXPECTED TO CONTINUE THROUGH THE WORKWEEK
WITH A CHANCE OF SHOWERS AND THUNDERSTORMS. OFFSHORE FLOW WILL
DEVELOP THIS WEEKEND AS A COLD FRONT MOVES ACROSS THE NORTHWEST
GULF LATE FRIDAY AND SATURDAY. LOWERED THE SCEC FOR THE COASTAL
LAKES AND BAYS WITH LATEST OBS NO LONGER SUPPORTIVE. HAZARDS OVER
THE GULF WATERS WERE RETAINED AS IS. DEWPOINTS IN THE UPPER 50S TO LOWER
60S ALREADY EXCEEDING WATER TEMPERATURES OVER MOST OF THE WATERS
WITHIN 20 NM. WITH THE PERSISTENT SOUTHERLY FETCH DRAWING AIR
CHARACTERIZED BY DEWPOINTS IN THE MID 60S...THIS DIFFERENCE IS
EXPECTED TO WIDEN AND INCREASE THE CHANCE OF SEA FOG LATER TONIGHT.

&&

.PRELIMINARY POINT TEMPS/POPS...
KLCH  60  73  62  75 /  70  20  20  50
KBPT  61  73  63  75 /  50  20  20  40
KAEX  56  74  62  75 /  90  20  20  60
KLFT  60  74  63  76 /  90  20  20  70

&&

.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 9 AM CST THURSDAY FOR WATERS FROM
     CAMERON, LA TO HIGH ISLAND, TX EXTENDING FROM 20 NM TO 60
     NM-WATERS FROM INTRACOASTAL CITY, LA TO CAMERON, LA
     EXTENDING FROM 20 NM TO 60 NM-WATERS FROM LOWER ATCHAFALAYA
     RIVER TO INTRACOASTAL CITY, LA EXTENDING FROM 20 NM TO 60
     NM.

&&

13

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE LAKE CHARLES LA
1138 AM CST WED DEC 29 2010

LAZ027>033-041>045-051>055-TXZ180>182-201-215-216-301745-
VERNON-RAPIDES-AVOYELLES-BEAUREGARD-ALLEN-EVANGELINE-ST. LANDRY-
CALCASIEU-JEFFERSON DAVIS-ACADIA-LAFAYETTE-UPPER ST. MARTIN-
CAMERON-VERMILION-IBERIA-ST. MARY-LOWER ST. MARTIN-TYLER-JASPER-
NEWTON-HARDIN-JEFFERSON-ORANGE-
1138 AM CST WED DEC 29 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL
LOUISIANA...SOUTH CENTRAL LOUISIANA...SOUTHWEST LOUISIANA...WEST
CENTRAL LOUISIANA AND SOUTHEAST TEXAS.

.DAY ONE...TODAY AND TONIGHT

AREAS OF LIGHT TO MODERATE RAIN OVER SOUTHEAST TEXAS WILL CONTINUE
TO EXPAND TOWARD THE EAST AND NORTHEAST ACROSS THE AREA TODAY AND
TONIGHT. AS INSTABILITY INCREASES THIS AFTERNOON...SO WILL THE
POTENTIAL FOR ISOLATED THUNDERSTORMS. WHILE WIDESPREAD SEVERE
WEATHER IS NOT EXPECTED...AND THE OVERALL PROBABILITY OF SEVERE
WEATHER IS LOW...AN ISOLATED SEVERE THUNDERSTORM OR TWO CANNOT BE
COMPLETELY RULED OUT. LARGE HAIL...DAMAGING WINDS...AND TORNADOES
WOULD BE POSSIBLE WITH ANY SEVERE THUNDERSTORM.

THE PRIMARY AREA OF CONCERN THIS AFTERNOON IS EASTERN TEXAS AND
WESTERN LOUISIANA. THIS EVENING...THE MAIN AREA OF RISK WILL SHIFT OUT
OF EAST TEXAS...BUT WILL INCLUDE ALL OF LOUISIANA. AFTER MIDNIGHT...EAST
AND SOUTH CENTRAL LOUISIANA.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THUNDERSTORM ACTIVITY FROM DAY ONE WILL END BY EARLY MORNING
THURSDAY...THOUGH A SLIGHT CHANCE OF SHOWERS WILL CONTINUE. NO HAZARDOUS
WEATHER IS EXPECTED ON THURSDAY.

ON FRIDAY...THUNDERSTORM CHANCES WILL ENTER THE FORECAST AGAIN AS
A COLD FRONT MOVES THROUGH THE AREA. AT THIS TIME...THERE IS A LOW
PROBABILITY OF SEVERE WEATHER FRIDAY AFTERNOON AND NIGHT.

NO HAZARDOUS WEATHER IS EXPECTED SATURDAY THROUGH TUESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED THIS AFTERNOON AND TONIGHT.

GMZ430-432-435-450-452-455-470-472-475-301745-
SABINE LAKE-CALCASIEU LAKE-VERMILION BAY-
COASTAL WATERS FROM CAMERON, LA TO HIGH ISLAND, TX OUT 20 NM-
COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON, LA OUT 20 NM-
COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY,
LA OUT 20 NM-
WATERS FROM CAMERON, LA TO HIGH ISLAND, TX EXTENDING FROM 20 NM
TO 60 NM-
WATERS FROM INTRACOASTAL CITY, LA TO CAMERON, LA EXTENDING FROM
20 NM TO 60 NM-
WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY, LA
EXTENDING FROM 20 NM TO 60 NM-
1138 AM CST WED DEC 29 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF THE NORTHWEST
GULF OF MEXICO.

.DAY ONE...TODAY AND TONIGHT

MODERATE TO STRONG SOUTHERLY WINDS AND ROUGH SEAS CAN BE EXPECTED.
A SMALL CRAFT ADVISORY IS IN EFFECT FOR THE GULF WATERS BEYOND 20
NM. SMALL CRAFT SHOULD EXERCISE CAUTION WITHIN 20 NM AND ON
COASTAL LAKES AND BAYS.

AREAS OF LIGHT TO MODERATE RAIN OVER THE NORTHWEST GULF WILL CONTINUE
TO EXPAND TOWARD THE EAST TODAY AND TONIGHT. AS INSTABILITY
INCREASES THIS AFTERNOON...SO WILL THE POTENTIAL FOR ISOLATED
THUNDERSTORMS. WHILE WIDESPREAD SEVERE WEATHER IS NOT
EXPECTED...AND THE OVERALL PROBABILITY OF SEVERE WEATHER IS
LOW...AN ISOLATED SEVERE THUNDERSTORM OR TWO CANNOT BE COMPLETELY
RULED OUT. LARGE HAIL...DAMAGING WINDS...AND WATERSPOUTS WOULD BE
POSSIBLE WITH ANY SEVERE THUNDERSTORM.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

MODERATE TO STRONG SOUTHERLY WINDS AND ROUGH SEAS WILL CONTINUE ON
THURSDAY.

MODERATE TO STRONG NORTHERLY WINDS WILL DEVELOP IN THE WAKE OF A
FRONT FORECAST TO MOVE THROUGH THE GULF WATERS LATE FRIDAY NIGHT.

.SPOTTER INFORMATION STATEMENT...

MARINE INTERESTS SHOULD BE ALERT TO RAPIDLY CHANGING WEATHER
CONDITIONS IN AND NEAR THUNDERSTORMS THIS AFTERNOON AND
TONIGHT...AND TAKE APPROPRIATE ACTION SHOULD A SPECIAL MARINE
WARNING BE ISSUED.

13

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LAKE CHARLES LA
522 PM CST WED DEC 29 2010

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0506 PM     WATER SPOUT      28 SSW ROCKEFELLER WILD 29.31N 92.96W
12/29/2010                   GMZ472             LA   PUBLIC

            OFFSHORE PLATFORM EAST CAMERON 81 REPORTED A WATERSPOUT
            SOUTHEAST OF THE PLATFORM

&&

DJONES

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LAKE CHARLES LA
815 PM CST WED DEC 29 2010

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0755 PM     TSTM WND GST     13 SSE PECAN ISLAND     29.47N 92.37W
12/29/2010  M41 MPH          GMZ452             LA   PUBLIC

            OIL PLATFORM REPORTED A MEASURED GUST OF 41 MPH.

&&

DJONES