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000 FXUS64 KLCH 262048 AFDLCH AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LAKE CHARLES LA 248 PM CST THU NOV 26 2009 .DISCUSSION... SURFACE HIGH PRESSURE THIS AFTERNOON LOCATED OVER CENTRAL TEXAS GRADUALLY MOVING OFF TO THE EAST. NORTH FLOW AROUND THE HIGH BRINGING IN A COOL AND DRY AIR MASS WITH DEWPOINTS IN THE UPPER 20S TO LOWER 30S. WATER VAPOR IMAGERY SHOWS UPPER LEVEL TROF AXIS FROM THE EASTERN GREAT LAKES TO THE NORTH CENTRAL GULF COAST MOVING QUICKLY TO THE EAST. AS THE TROF MOVES OFF TO THE EAST...UPPER LEVEL EAST PACIFIC MOISTURE IS MOVING ACROSS OLD MEXICO AND TEXAS TOWARD THE FORECAST AREA. CHALLENGE IN THE SHORT TERM IS THE FORECAST FOR THE OVERNIGHT LOWS. WITH THE EXPECTED LIGHT AND VARIABLE TO...AT TIMES...CALM WINDS...AND DRY AIR MASS WITH LOW DEWPOINTS...TEMPERATURES SHOULD BE ABLE TO DROP FAIRLY QUICKLY AFTER SUNSET WITH SOME OF THE COLDEST TEMPERATURES SO FAR THIS SEASON LIKELY. IT LOOKS LIKE CIRRUS CLOUDS ASSOCIATED WITH THE EAST PACIFIC MOISTURE WILL BE MOVING ACROSS WITH THE SUBTROPICAL JET. THEREFORE...THIS MAY INDEED HELP KEEP TEMPERATURES FROM "BOTTOMING OUT"...AND WILL NOT ISSUE A NPW FOR A FREEZE WARNING. SOME ISOLATED SPOTS IN THE USUALLY COLD LOCATIONS IN THE EXTREME NORTHERN ZONES MAY BRIEFLY NEAR FREEZING FOR AN HOUR OR TWO. AT ANY RATE WITH THE CALM WINDS AND TEMPERATURES IN THE LOW TO MID 30S...SHOULD SEE SOME FROST...ESPECIALLY AROUND HIGHWAY 190 AND NORTHWARD. WILL ISSUE A SPECIAL WEATHER STATEMENT TO COVER THIS. THE HIGH PRESSURE SYSTEM WILL BE EAST OF THE AREA BY FRIDAY NIGHT WITH LIGHT RETURN FLOW BEGINNING AND A MODERATION IN TEMPERATURES FOR THE WEEKEND. NEXT COLD FRONT LOOKS TO COME ACROSS THE FORECAST AREA ON MONDAY. SHOULD BE SIGNIFICANT MOISTURE RETURN AHEAD OF THIS FRONT TO CALL FOR A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS BEGINNING ON SUNDAY NIGHT INTO MONDAY. EVEN THOUGH THE FRONT MOVES OFFSHORE MONDAY NIGHT...ACTIVE SOUTHWEST AND MOIST FLOW ALOFT WILL CONTINUE TO OVERRIDE THIS FRONT WITH COOL...CLOUDY AND RAINY CONDITIONS POSSIBLE INTO WEDNESDAY. RUA && .MARINE... A COUPLE OF SHIP REPORTS RECENTLY 60 NM OFFSHORE SHOW NORTHERLY WINDS AROUND 20 KNOTS. WILL KEEP THE SMALL CRAFT ADVISORY GOING FOR THE OUTER COASTAL WATERS FOR ONE MORE FORECAST CYCLE UNTIL WINDS BEGIN TO DECREASE. WINDS SHOULD CONTINUE TO DECREASE OVERNIGHT AS THE CENTER OF A SURFACE HIGH MOVES NEAR THE COASTAL WATERS. THIS HIGH WILL BE MOVING OFF TO THE EAST ON FRIDAY NIGHT INTO SATURDAY ALLOWING FOR LIGHT RETURN FLOW OFF THE GULF TO START. THE SOUTHERLY WINDS WILL INCREASE ON SATURDAY NIGHT INTO SUNDAY AS A COLD FRONT BEGINS TO APPROACH THE AREA...WITH SCATTERED SHOWERS ALSO BEGINNING TO DEVELOP. THIS COLD FRONT IS EXPECTED TO MOVE INTO THE COASTAL WATERS ON MONDAY WITH STRONG NORTHERLY WINDS DEVELOPING BEHIND IT WITH SMALL CRAFT ADVISORY CONDITIONS AGAIN LIKELY. RUA && .PRELIMINARY POINT TEMPS/POPS... KLCH 36 64 48 70 56 / 0 0 0 10 10 KBPT 38 66 49 71 59 / 0 0 0 10 20 KAEX 34 64 41 69 51 / 0 0 0 10 10 KLFT 35 64 43 70 55 / 0 0 0 10 10 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...NONE. TX...NONE. GM...SMALL CRAFT ADVISORY UNTIL 9 PM CST THIS EVENING FOR THE FOLLOWING ZONES: 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. && $$