000 AGXX40 KNHC 162007 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 306 PM 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 EXTENDS FROM THE SW N ATLC WATERS JUST E OF THE BAHAMAS W ALONG 26N IN THE E GULF. S TO SW RETURN FLOW OF 20-25 KT PREVAILS FROM THE SW GULF N THEN NE ACROSS THE N CENTRAL PORTIONS...AND IS GRADUALLY SHIFTING E INTO NE PORTIONS. WINDS WILL BEGIN TO DIMINISH THIS EVENING AHEAD OF A COLD FRONT APPROACHING THE TEXAS COAST...BUT LIKELY REMAIN SW 20-25 ALONG THE FLORIDA PANHANDLE COASTAL WATERS...THEN DROP OFF TO 15 TO 20 KT OVERNIGHT. THE FRONT WILL MOVE ACROSS THE TEXAS COASTAL WATERS THIS EVENING AND WITH SUPPORTING S/W ENERGY LIFT OUT TO THE NE AND OFF THE E COAST...THE BOUNDARY BECOME STRUNG OUT ACROSS THE NW GULF THROUGH FRI WILL SLOWLY SOUTHWARD PROGRESS. THIS WEAKENING FRONT WILL FINALLY MOVE S TO JUST S OF 25N ALONG THE MEXICAN COAST SAT MORNING...EXTENDING TO THE FLORIDA BIG BEND REGION WHERE MODELS DEVELOP A LOW AND FRONTAL WAVE THAT LIFT NE SAT AND SAT NIGHT. THIS WILL ALLOW FOR A MORE DECIDEDLY NLY FLOW TO BUILD IN ACROSS THE BASIN SAT NIGHT THROUGH SUN EVENING...BEFORE RETURN FLOW BEGINS TO SET UP W AND NW PORTIONS EARLY MON MORNING. THIS RETURN FLOW SCENARIO WILL GO THROUGH A SIMILAR EVOLUTION AS THE CURRENT EVENT...GRADUALLY INCREASING AND BECOMING S TO SW THEN SHIFTING E INTO THE NE GULF MON NIGHT INTO TUE BEFORE THE NEXT FRONT DROPS INTO N PORTIONS TUE NIGHT. 20 KT NLY WINDS ARE EXPECTED ACROSS THE WRN GULF BEHIND THE FRONT AND ALONG THE MEXICAN COAST SAT WHERE SEAS WILL BUILD 6 TO 7 FT. OTHERWISE...WIND AND SEAS ARE MODERATE THROUGH THIS PERIOD. CARIBBEAN AND TROPICAL N ATLC W OF 55W... THE OLD FRONTAL BOUNDARY EXTENDS NE TO SW ACROSS N PORTIONS OF THE TROPICAL N ATLC WATERS...AND ENTERS THE CARIBBEAN AS A SHEAR AXIS NEAR ANTIGUA...THEN MEANDERS W TO W-SE ACROSS THE N CARIBBEAN TO NEAR 15N75.5W. AS IS TYPICAL...FRESH NE TO E WINDS ARE TRAPPED TO THE N OF THE SHEAR AXIS...WITH A 1456 UTC ASCAT PASS REVEALING 25-30 KT FLOW ACCELERATING DOWNWIND OF THE MONA PASSAGE AND ERN TIP OF HISPANIOLA...WHILE ALSO SHOWING NE WINDS TO 25 KT THROUGH THE WINDWARD PASSAGE. THE SHEAR AXIS WILL WEAKEN THROUGH SAT AS IT DRIFTS W...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. THE LOW OR WAVE ALONG THE GULF FRONT SAT WILL HELP TO INDUCE WEAK FLOW ACROSS THE W AND SW GULF...WITH A WEAK TROUGH PERSISTING THERE...AND ALLOW FOR THE W END OF THE SHEAR LINE TO LIFT N ACROSS JAMAICA AND MAINTAIN THE 20 KT ELYS TO THE N OF 15N THROUGH LATE SAT NIGHT. A GALE DEVELOPING ACROSS THE NW ATLC SAT NIGHT AND SUN WILL ALLOW FOR A FRONT TO MOVE ACROSS FLORIDA AND INTO THE CENTRAL BAHAMAS AND WEAKEN THE GRADIENT AND TRADES ACROSS THE CARIB BASIN THROUGH TUE. N-NW LONG PERIOD SWELL HAS PEAKED ACROSS THE NE CARIB AND THROUGH THE PASSAGES AND WILL GRADUALLY ABATE SAT AND SAT NIGH. SW N ATLC S OF 31N W OF 55W... 1021 MB HIGH PRES LOCATED NEAR 25.5N73W EXTENDING W ACROSS FLORIDA. FRESH N-NE TO NE WINDS WERE DEPICTED S OF 22N ACROSS THE ATLC WATERS N OF THE NE CARIB BY A 1452 UTC ASCAT PASS...AND WERE ACCELERATING THROUGH THE PASSAGES. MILD SLY FLOW HAS DEVELOP OFF THE E COAST OF FLORIDA TO 79W. A 1050 UTC WINDSAT PASS SHOWED GALES EXTENDING S INTO THE WATERS JUST TO THE NE OF THE AREA...BEHIND A SECONDARY COLD FRONT...THAT WILL SHIFT NE OF THE HIGH SEAS AREA THIS AFTERNOON. THE SOUTHERLY RETURN FLOW THAT HAS BEGUN TO SET UP ALONG THE FLORIDA/GEORGIA COASTS WILL BECOME 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 CONTINUED TO BACK OFF OF THE POTENTIAL FOR GALE FORCE WINDS AHEAD OF THE FRONT AND HAVE ACCORDINGLY TRIMMED GALE WORDING FROM N OF 27N TO N OF 28N...AND COULD BE TRIMMED FURTHER OR DROPPED DURING NEXT FEW FORECAST CYCLES. 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 PULSE 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 SUN. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER STRIPLING