Flash Flood Warning 47, NWS Lake Charles, LA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAKE CHARLES LA
1001 PM CST THU DEC 17 2009

.UPDATE...
ADJUSTED POPS/WX AS RAIN HAS ENDED ACRS SE TX AND WILL BE TAPERING
OFF ACRS WRN LA THROUGH MIDNIGHT. MODERATE TO OCCASIONALLY HEAVY
RAIN WILL CONTINUE ACRS CNTRL AND S CNTRL LA FOR THE NEXT FEW
HOURS AS DEEP MOISTURE WRAPS AROUND THE NORTH SIDE OF A 1008MB SFC
LOW OVER THE GULF OF MEXICO WITH A POTENT SHORTWAVE PASSING ALOFT.
DESPITE THIS AREA RECEIVING QUITE A BIT OF RAIN RECENTLY...NO
SIGNIFICANT FLOODING HAS BEEN REPORTED SO FAR THIS EVENING. THE
VERMILION RIVER AT SURREY STREET IN LAFAYETTE HAS EXCEEDED FLOOD
STAGE...BUT WITH THE HEAVIEST RAIN NOW MOVING OFF TO THE
NE...EXPECT THE RIVER TO CREST TONIGHT NEAR OF JUST BELOW 11 FEET
WHICH IS IN THE MINOR CATEGORY.

IN ADDITION...ADJUSTED LOW TEMPERATURES DOWNWARD SLIGHTLY AS LATEST OBS
SHOW TEMPS ALREADY APPROACHING FCSTED LOWS. EXPECT TEMPERATURES TO
DROP ANOTHER 3 TO 5 DEGREES OVER THE WRN ZONES AS SOME CLEARING IS
EXPECTED BEFORE DAYBREAK. ON THE OTHER HAND...TEMPERATURES WILL
PROBABLY ONLY DROP ANOTHER DEGREE OR TWO ACRS PORTIONS OF CNTRAL
AND S CNTRAL LA WHERE CLOUDS WILL LIKELY NOT CLEAR OUT UNTIL
FRIDAY MORNING.

CONDITIONS EXPECTED TO IMPROVE THROUGH THE NIGHTTIME HOURS...WITH
RAINFALL MOVING EAST OF THE AREA BY 12Z. A RATHER NICE DAY SHAPING
UP FOR FRIDAY...AND FINALLY SOME SUNSHINE...AS HIGH PRESSURE
BUILDS INTO THE REGION. 24

&&

.PREV DISCUSSION... /ISSUED 712 PM CST THU DEC 17 2009/

UPDATE...
UPDATED ZONES AND GRIDS TO REFLECT RECENT RADAR TRENDS OF
WIDESPREAD LIGHT TO MODERATE RAIN CONTINUING ACROSS SRN AND CNTRL
LA WITH RAIN BEGINNING TO TAPER OFF ACRS SE TX. ADJUSTED POPS
UPWARD ACRS THE AREA FOR THE EVENING HOURS...WITH CHC TO LIKELY
POPS ACRS LA ZONES CONTINUING AFTER MIDNIGHT. ALSO ADJUSTED SKY
COVER WITH CLOUDS GRADUALLY DECREASING AFTER MIDNIGHT. REMAINDER
OF FCST LOOKS FINE FOR NOW...BUT WILL MONITOR FOR POSSIBLE UPDATES
LATER THIS EVENING. 24

PREV DISCUSSION... /ISSUED 633 PM CST THU DEC 17 2009/

AVIATION...
RAIN ACTVTY IS TAPERING OFF ACROSS SOUTHEAST TEXAS WITH RAINS
CONTINUING ACROSS MOST OF SOUTH AND CENTRAL LOUISIANA THIS
EVENING. RAINS WILL GRADUALLY TAPER OFF SOUTHERN LOUISIANA LATE
THIS EVE AND INTO THE OVERNIGHT HOURS. IFR DUE TO CEILINGS ALONG
THE COAST WITH CEILINGS RISING IN CNTRL LA AND THE LAKES REGION OF
SE TX. CONDITIONS WILL HOLD PRETTY MUCH WERE THEY ARE NOW WITH A
GRADUAL IMPROVEMENT TOWARDS SR.

PREV DISCUSSION... /ISSUED 326 PM CST THU DEC 17 2009/

SYNOPSIS...A ROBUST LOW PRESSURE OVER CENTRAL GULF WILL CONTINUE
TO INTENSIFY AND MOVE NORTHEAST. A RAIN SHIELD ASSOCIATED WITH
THIS LOW WILL TAPER OFF FROM THE WEST LATER THIS EVENING. COOL AND
DRY CONDITIONS WILL BE THE RULE LATE TONIGHT AND INTO EARLY NEXT
WEEK AS STRONG HIGH PRESSURE BUILDS IN FROM THE NORTHWEST. AN
INTENSE WINTER STORM SYSTEM DEVELOPING OVER THE ROCKIES WILL MOVE
INTO THE SOUTHERN PLAINS AROUND THE MIDDLE OF NEXT WEEK. ARCTIC
AIR INTO THE PANHANDLE ON CHRISTMAS EVE COULD FEED INTO DEPARTING
WRAPAROUND MOISTURE FROM THE INTENSE LOW MOVING OUT OF THE SOUTHERN
PLAINS AND PRODUCE A WINTRY MIX FOR THE NORTHERN PORTIONS OF OUR
FORECAST AREA ON CHRISTMAS EVE.

SHORT TERM...LIKELY LIGHT RAIN OVER THE SOUTHERN ZONES AND
SCATTERED LIGHT RAIN TO THE NORTH THIS EVENING WILL GIVE TAPER OFF
FOR THE AREA WITH THE EXCEPTION OF ACADIANA WHERE SOME OF THE
PRECIP WILL PERSIST BEYOND MIDNIGHT CLOSER TO THE GULF LOW. SKIES
SHOULD CLEAR ON FRIDAY AS COOLER AND MUCH DRIER AIR MOVES IN FROM
THE NORTHWEST.

LONG TERM...THERE ARE MODEL DIFFERENCES MONDAY INTO WEDNESDAY.
THE GFS WAS FAVORED ON THE WEAKER EURO WITH THE INTENSIFYING
WESTERN STORM WHICH IS DRIVEN BY A STRONG DESCENDING POLAR JET OUT
OF THE NORTH PACIFIC. THE GFS IS MORE SENSITIVE TO UPPER LEVEL
RAOBS AND ACFT DATA AND SHOULD BE MORE RESPONSIVE TO THIS TYPE OF STORM.
CORRESPONDING THICKNESS VALUES ARE EASILY WITHIN THE BALLPARK FOR
SNOW ON CHRISTMAS EVE IN AN AREA WITH WRAPAROUND MOISTURE FROM THE
DEPARTING LOW. MEX DATA LOOKS REASONABLE WITH 20 POPS OVER THE
NORTHERN PORTION OF THE AREA COVERING THE LAKES AREA OF SE TX TO
CENTRAL LOUISIANA. MERGING IN WARMER EURO VALUES SUPPORTS A MIXTURE
OF RAIN AND SNOW FOR THOSE AREAS. ITS NOT TOO EARLY TO ADJUST
THOSE TRAVEL PLANS AROUND CHRISTMAS FOR THE 23RD VS THE 24TH.
OF COURSE, THIS FAR OUT TIMING COULD BE OFF BY A DAY.

MARINE...EXTENDED THE SMALL CRAFT ADVISORY ANOTHER 24 HOURS DUE
TO THE INTENSIFICATION OF THE GULF LOW AS IT DEPARTS THE AREA.
HIGH PRESSURE BUILDING IN FROM THE NORTHWEST SHOULD ALLOW WINDS TO
SUBSIDE BELOW SCA CRITERIA BY SUNRISE ON SATURDAY.

SWEENEY

&&

.PRELIMINARY POINT TEMPS/POPS...
KLCH  40  60  42  61 /  70  10  10  10
KBPT  40  63  41  61 /  10  10  10  10
KAEX  39  59  39  57 /  80  10  10  10
KLFT  42  59  41  59 / 100  10  10  10

&&

.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 6 AM CST SATURDAY FOR 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.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LAKE CHARLES LA
403 AM CST THU DEC 17 2009

LAZ027>033-041>045-051>055-TXZ180>182-201-215-216-181015-
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-
403 AM CST THU DEC 17 2009

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
LIGHT RAIN WILL SPREAD OVER MOST OF THE REGION TODAY. AT THIS
TIME...HEAVY RAINFALL IS NOT ANTICIPATED AND NO HAZARDOUS WEATHER
IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.

GMZ430-432-435-450-452-455-470-472-475-181015-
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-
403 AM CST THU DEC 17 2009

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

.DAY ONE...TODAY AND TONIGHT
A SURFACE LOW WILL DEVELOP OVER THE WESTERN GULF TODAY AND MOVE
OVER THE NORTHEAST GULF TONIGHT. THE DEVELOPMENT OF THIS LOW WILL
RESULT IN INCREASING WINDS AND SEAS TODAY AND TONIGHT. A SMALL
CRAFT ADVISORY HAS BEEN ISSUED. OTHERWISE...NO HAZARDOUS WEATHER
IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY
WINDS MAY REACH SMALL CRAFT ADVISORY LEVELS THIS
WEEKEND...ESPECIALLY OVER THE OFFSHORE WATERS. OTHERWISE...NO
HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.