000 AGXX40 KNHC 160654 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 200 AM EST THU DEC 16 2010 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND TROPICAL N ATLC...AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... A RIDGE EXISTS ALONG 26-27N IN THE GULF WATERS EXTENDING FROM 1020 MB HIGH PRES LOCATED NEAR ORLANDO FLORIDA. SOUTHERLY RETURN FLOW IS 20-25 KT ACROSS THE W GULF WITH 15-20 KT WINDS IN THE CENTRAL GULF AS SHOWED BY A 0228 UTC ASCAT PASS AND AN EARLIER 0002 UTC WINDSAT PASS. A 0210 UTC JASON ALTIMETER PASS INDICATED 9 FT SEAS IN THE NW GULF AND BUOY OBSERVATIONS ALSO CURRENTLY REPORT 8-9 FT. SOUTHERLY RETURN FLOW WILL DIMINISH ACROSS THE GULF TODAY AS THE NEXT COLD FRONT APPROACHES THE TEXAS COAST. THE FRONT WILL ENTER THE NORTHERN WATERS TONIGHT REACHING FROM THE FLORIDA PANHANDLE TO JUST S OF LOUISIANA TO 22N98W BY EARLY FRI MORNING THEN FROM NEAR APALACHEE BAY FLORIDA TO THE BAY OF CAMPECHE FRI EVENING MOVING E OF THE GULF SAT NIGHT. LOW PRES MAY DEVELOP ALONG THE FRONT JUST S OF LOUISIANA FRI EVENING MOVING E ACROSS FLORIDA TO THE ATLC SAT. LATEST MODEL GUIDANCE HAS TRENDED WEAKER WITH RESPECT TO THE NORTHERLY WINDS BEHIND THE FRONT WITH THE GFS AND ECMWF BOTH INDICATING 15-20 KT WINDS VERSUS THE 20-25 KT WINDS THAT BOTH MODELS WERE SHOWING WITH PREVIOUS MODEL RUNS. HIGH PRES BUILDS IN BEHIND THE FRONT SAT NIGHT WITH A NE TO SW RIDGE EXTENDING ACROSS THE GULF SUN THROUGH MON WITH SOUTHERLY RETURN FLOW ONCE AGAIN INCREASING OVER THE W GULF LATE MON INTO TUE. CARIBBEAN AND TROPICAL N ATLC W OF 55W... A SHEAR AXIS REMAINS OVER THE CENTRAL AND E CARIBBEAN EXTENDING FROM NEAR GUADELOUPE TO NEAR 14N70W TO NORTHERN COLOMBIA NEAR 11N75W. A 0224 UTC ASCAT PASS INDICATED NE TO E 25-30 KT WINDS IN THE LEE OF HISPANIOLA INCLUDING THE MONA PASSAGE WITH N-NE 15-20 KT WINDS ACROSS THE W CARIBBEAN ALONG WITH 5-10 KT NE-E WINDS SE OF THE SHEAR AXIS. THE SHEAR AXIS WILL DISSIPATE BY TONIGHT AS HIGH PRES BUILDS N-NE OF THE AREA WITH MODERATE TO FRESH TRADES SETTING UP ACROSS THE CENTRAL AND E CARIBBEAN FRI AND SAT WITH E-SE 10-15 KT WINDS OVER THE W CARIBBEAN. WINDS BECOME LIGHT AND VARIABLE IN THE W CARIBBEAN SAT AS A WEAK COLD FRONT APPROACHES THE NW PORTION FROM THE GULF. WINDS SHIFT TO NW-N AND INCREASE BACK TO 10-15 KT W OF THE FRONT SUN AND MON. THE FRONT WILL REACH FROM NEAR CENTRAL CUBA TO CENTRAL PANAMA SAT NIGHT THEN FROM NEAR HISPANIOLA TO NORTHERN CUBA SUN NIGHT WHERE IT WILL STALL OUT AND DISSIPATE MON. IN THE TROPICAL N ATLC...A WEAKENING COLD FRONT EXTENDS FROM NEAR 22N57W TO GUADELOUPE AND A 0044 UTC ASCAT PASS CAPTURED NW-N 10-15 KT WINDS BEHIND THE FRONT EXCEPT TO 20 KT NEAR THE CARIBBEAN/ATLC PASSAGE AS REPORTED BY LAND-BASED ISLAND OBSERVATIONS AND SEVERAL SHIPS...WITH 5-10 KT VARIABLE WINDS AHEAD OF THE FRONT OVER THE REMAINDER OF THE BASIN. NW SWELL 10-12 FT HAS ARRIVED BEHIND THE FRONT AS RECENTLY OBSERVED BY NDBC BUOY 41044 LOCATED NEAR 21.5N58W. THIS FRONT WILL SHIFT E OF THE AREA LATER THIS MORNING AS HIGH PRES BUILDS IN FROM THE NW. MODERATE TO FRESH TRADES WILL DEVELOP TONIGHT WHICH WILL THEN HOLD THROUGH EARLY SUN. TRADES WEAKEN SUN AFTERNOON AS THE NEXT COLD FRONT APPROACHES THE NW PUSHING INTO THE FAR NW PORTION MON NIGHT. SW N ATLC S OF 31N W OF 55W... 1020 MB HIGH PRES LOCATED INLAND NEAR ORLANDO FLORIDA HAS A RIDGE AXIS EXTENDING ACROSS THE SW N ATLC ROUGHLY ALONG 26-27N. RECENT WINDSAT AND ASCAT SCATTEROMETER PASSES SHOWED LINGERING W-NW 20-30 KT WINDS IN THE N CENTRAL PORTION BEHIND A STRONG COLD FRONT WHICH HAS NOW MOVED E OF THE AREA. LARGE NW SWELL REMAINS OVER THE NE WATERS WITH A 0010 UTC JASON ALTIMETER PASS REPORTING 14 FT SEAS NEAR 30N63W. THE HIGH WILL MOVE TO NEAR 28N72W THIS AFTERNOON WITH THE AREA OF STRONGER WINDS SHIFTING TO THE NE CORNER OF THE BASIN. MEANWHILE SOUTHERLY RETURN FLOW SETS UP ALONG THE FLORIDA/GEORGIA COASTS BECOMING SW AND INCREASING TO 20-25 KT N OF 29N AS A COLD FRONT SKIRTS THE FAR NORTHERN WATERS TONIGHT THROUGH FRI NIGHT. A REINFORCING FRONT MOVES OFF THE SE U.S. COAST SAT REACHING FROM NEAR 31N76W TO CENTRAL CUBA SUN MORNING THEN QUICKLY E FROM NEAR 31N65W TO CENTRAL HISPANIOLA MON MORNING AND FINALLY FROM NEAR 31N56W TO THE VIRGIN ISLANDS BY LATE MON. LOW PRES MAY DEVELOP ALONG THE FRONT OVER THE GULFSTREAM SAT NIGHT QUICKLY PULLING NE OF THE AREA SUN. MODEL GUIDANCE HAS BACKED OFF SLIGHTLY ON THE POTENTIAL FOR GALE FORCE WINDS AHEAD OF THE FRONT AND HAVE ACCORDINGLY TRIMMED GALE WORDING FROM N OF 27N TO N OF 28N. ALSO EXPECT ANOTHER ROUND OF W-NW 20-30 KT WINDS BEHIND THE FRONT OVER THE NORTHERN HALF OF THE AREA WITH 15-20 KT WINDS OVER THE SOUTHERN HALF BEHIND THE FRONT. A NEW SET OF NW SWELL WILL ALSO ARRIVE BEHIND THE NEXT FRONT WITH SEAS BUILDING TO UP TO 16 FT NEAR 31N65W BY LATE MON. WARNINGS... ATLC... .AMZ080...GALE CONDITIONS EXPECTED N OF 28N E OF FRONT LATE SAT AND SUN. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER LEWITSKY