000 AGXX40 KNHC 131910 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 210 PM EDT TUE NOV 13 2007 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... MODERATE TO FRESH NE TO E FLOW CONTINUES ACROSS THE FAR SOUTHERN GULF ON THE PERIPHERY OF HIGH PRES CENTERED OVER SE GEORGIA. SHIP WITH CALL LETTER ID PCEX NEAR 24N87W HAD A REPORTED 20 KT E WINDS AT 1200 UTC WITH A SIGNIFICANT WAVE HEIGHT OF 6 FT. VIS SATELLITE IMAGERY SHOWS LOW CLOUD MOTION TO BE RATHER QUICK OUT OF THE NE IN THIS FLOW OVER THIS PART OF THE GULF. THESE WINDS AND SEAS WILL SUBSIDE THROUGH WED AS THE HIGH MOVES E AND DISSIPATES AHEAD OF A DEEPENING UPPER TROUGH PRESENTLY OVER THE NORTHERN ROCKIES THAT WILL BE MOVING THROUGH THE CENTRAL MISSISSIPPI VALLEY THROUGH WED. THE UPPER TROUGH WILL BE ATTENDED BY A SURFACE COLD FRONT THAT IS SCHEDULED TO ENTER THE FAR NW GULF THU MORNING...AND MOVE TO A LINE FROM NEAR THE FLORIDA BIG BEND TO NE MEXICO BY THU AFTERNOON...AND E OF THE GULF THU NIGHT. MAIN ISSUE WITH THIS FRONT WILL BE WITH NLY WINDS FOLLOWING IN ITS WAKE. 1200 UTC GFS/UKMET/ECMWFHR AND EVEN THE NAM MODEL RUNS AGREE ON N-NE 20-25 KT WINDS BEHIND THE FRONT THU THROUGH AT LEAST FRI AFTERNOON WITH THE GFS SHOWING UP TO 30 KT ALONG NEAR THE NE TEXAS AND SW LOUISIANA COASTS EARLY THU. BASED ON THIS TREND...WILL CONTINUE WITH THESE SPEEDS BEHIND THE FRONT ON THU AS UPDATED ON THIS MORNING'S 930 AM CDT FORECAST. I BELIEVE ANY 30 KT WILL BE CONFINED ALONG COASTAL WATERS OF NE TEXAS AND SW LOUISIANA BUT SHOULD BRIEF. SEAS PER 1200 UTC WAVEWATCH GUIDANCE ARE EXPECTED TO POSSIBLY BUILD UP TO 11 FT THU NIGHT AND FRI OVER THE MIDDLE AND EASTERN PORTIONS OF THE GULF IN THE WAKE OF THE FRONT. HIGH PRES WILL THEN QUICKLY SLIDE EASTWARD TO OFFSHORE THE SE UNITED STATES BY SAT NIGHT ALLOWING FOR WINDS ACROSS THE GULF TO VEER AROUND TO THE E-SE AND DIMINISH TO 10-15 KT INTO SUN WITH SEAS LOWERING TO THE RANGE OF 2-4 FT. SW N ATLANTIC... BOTH QUIKSCAT AND ASCAT DATA FROM THIS MORNING REVEALED AN AREA OF NE 20-25 KT WINDS PRIMARILY S OF 26N E OF THE BAHAMAS. IN ADDITIONAL SEVERAL SHIPS E OF THE SE BAHAMAS REPORTED SIMILAR WIND SPEEDS WITH SEAS 6-8 FT DURING THE MORNING. THIS IS DUE TO A TIGHTENING PRES GRADIENT BETWEEN HIGH PRES LOCATED OVER SOUTHERN GEORGIA AND TROUGHINESS JUST SE OF THE AREA. LINGERING NE SWELL UP TO 8 FT IS STILL BEING OBSERVED OVER THE NE PART PERHAPS SUBSIDING SLIGHTLY BEFORE IMPACTING WATERS FROM SE BAHAMAS TO VICINITY PUERTO RICO AND MONA PASSAGE AS PORTRAYED BY THE WAVEWATCH GUIDANCE INCLUDING THE UKMET WAVE GUIDANCE. WINDS AND SEAS OVER REMAINDER OF THE AREA WILL SUBSIDE THROUGH EARLY THU...EXCEPT THE FAR NW PORTION IN ADVANCE OF THE COLD FRONT MENTIONED ABOVE UNDER GULF OF MEXICO. WINDS THERE BECOME SW AND INCREASE TO 20-25 KT AHEAD OF THE FRONT THU AND THU NIGHT. THE FRONT IS FORECAST TO EXTEND TO BE JUST OFFSHORE THE GEORGIA AND NE FLORIDA COAST THU AFTERNOON ...FROM ABOUT 31N74W TO CENTRAL CUBA LATE THU NIGHT THEN FROM 31N67W TO E CUBA BY FRI AFTERNOON AND WEAKEN OVER THE FAR SE WATERS FRI NIGHT THROUGH SAT BEFORE DISSIPATING SAT NIGHT INTO SUN. WINDS BEHIND THE FRONT ARE EXPECTED TO BE NW 20-25 KT...DIMINISHING TO 15-20 KT SAT AS HIGH PRES BECOMES ALIGNED ALONG 32N. WINDS THEN FURTHER DECREASE TO E 10-15 KT SUN OVER MOST OF THE AREA...EXCEPT TO VARIABLE 5-10 KT FAR NW PART AND HIGHER WINDS E DIRECTION IN THE 15-20 KT RANGE IN THE FAR SW PART NEAR THE BAHAMAS AS GRADIENT THERE WILL BE SLOW IN RELAXING. CARIBBEAN AND TROPICAL N ATLC... WINDS ACROSS THE NE CARIBBEAN HAVE WEAKENED SLIGHTLY DURING THE MORNING...HOWEVER A COUPLE OF SHIP OBSERVATIONS ALONG WITH A QUIKSCAT PASS FROM NEAR 1100 UTC THIS MORNING REVEALED NE-E 15-20 KT. SEAS ARE SLOWLY SUBSIDING THERE AS WELL. THIS SAME QUIKSCAT PASS ALONG WITH A 1416 UTC ASCAT PASS AND SHIP REPORTS FROM THIS MORNING SHOWED NE 20-25 KT WINDS IN THE SW CARIBBEAN BETWEEN 72W-82W. TRADES ACROSS THE REMAINDER OF THE CARIBBEAN SEA AND TROPICAL N ATLC ARE IN THE 10-15 KT RANGE...BUT WILL PICK UP TO 15-20 KT OVER MOST OF THE E CARIBBEAN AND W PORTION OF THE TROPICAL N ATLC SAT INTO SUN DUE TO THE RESULTANT PRES GRADIENT BETWEEN HIGH PRES OVER THE ATLC AND LOWER PRES OVER THE FAR SOUTHERN CARIBBEAN AND S AMERICA. WINDS WILL ALSO INCREASE TO NLY 20 KT THU AND FRI OVER THE NW CARIBBEAN SEA AS STRONG HIGH PRES BUILDS SE ACROSS THE SE GULF AND NW CARIBBEAN BEHIND THE COLD FRONT THAT MOVES FROM THE GULF OF MEXICO INTO THE ATLC AS DESCRIBED IN ABOVE PARAGRAPHS. THE WINDS THEN VEER TO NE-E SAT AND SUN BUT STAY AT 15-20 KT E OF ABOUT 81W WITH SEAS IN THE 5-7 FT RANGE. INCREASED SCATTERED STRONG TSTM ACTIVITY OVER THE FAR SW CARIBBEAN SEA LEFT BEHIND BY A TROUGH NOW OVER HONDURAS IS CAPABLE OF PRODUCING WINDS GUSTS TO 30 KT...BUT SHOULD LAST THROUGH AT LEAST WED NIGHT. WARNINGS... ATLC... NONE. CARIBBEAN... NONE. GULF OF MEXICO... NONE. FORECASTER AGUIRRE