000 AGXX40 KNHC 281854 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 254 PM EDT Thu Sep 28 2017 Marine Weather Discussion for the Gulf of Mexico, Caribbean Sea, and Tropical North Atlantic from 07N to 19N between 55W and 64W and the Southwest North Atlantic including the Bahamas. ...GULF OF MEXICO... A cold front will enter the northwestern gulf tonight then stall out from around Tampa Bay to the Texas/Mexico border later on Friday. In the meantime, mainly moderate east to northeast winds will prevail north of the front through Saturday. By later on Sunday, models are indicating an area of low pressure to develop along the front, with some of the energy from this low moving westward over the northeastern Gulf Sunday afternoon. The pressure gradient between this front/low low pressure and high pressure to the north will result in fresh to strong northeast winds over the northeast gulf Sunday through Tuesday, with seas building to 8 ft. Since models currently vary in their interpretation of this low, this portion of the forecast is low confidence. The interaction of an upper low over the east central Gulf and a tropical wave energy and deep moisture over the NW Caribbean and Yucatan Channel, will draw showers and thunderstorms across the southeastern Gulf the next several days. A thermal trough will develop each evening in the NW Yucatan Peninsula, move W-NW across the SW Gulf during the overnight hours and dissipate in the SW Gulf waters by late each morning. Expect the trough to be accompanied by a surge of moderate to locally fresh winds that shift from NE to SE along with seas possibly briefly reaching 4 ft. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... The combination of tropical wave energy over central America and upper level diffluence over the northwestern Caribbean continues to support clusters of convection over the northwestern Caribbean. This pattern will remain in place through the weekend. A sharp upper trough extending from the western Atlantic to the eastern Caribbean supporting numerous showers and thunderstorms across the Leeward islands and surrounding waters will shift westward the next couple of days spreading the unsettled weather across the Virgin Islands, Puerto Rico, and much of the eastern Caribbean. Moderate to fresh trades will cover much of the Caribbean through Saturday, then decrease to gentle to moderate later this weekend into early next week as ridging north of the basin weakens slightly. A tropical wave crossing 55W tonight will cross the Leeward Islands this weekend, and the eastern Caribbean early next week. ...SW N ATLANTIC INCLUDING THE BAHAMAS... Swell produced by Tropical Storm Maria, presently well N of the area will continue to propagate through the forecast waters NE of the Bahamas through Friday night while slowly decaying. A weak pressure pattern to the south of Maria, under a ridge axis, will promote gentle to moderate winds over most of the zones through Friday. The only exception will be across the northeast zone AMZ115 through tonight as southwest flow associated with Maria remains over the area. The forecast becomes more complex this weekend as models are forecasting a cold front to stall out over the Northwestern waters, as an area of low pressure develops between the Bahamas and Florida Saturday, before the low merges with the frontal boundary Saturday night. In the meantime, high pressure will build southeast over the eastern United States, helping to tighten the pressure gradient and increasing winds to strong to near gale over the northwest waters north of the low. Seas are currently forecast to build to 8 to 12 ft Saturday night through Sunday during the peak winds, before the low begins to shear out and winds decrease to 20 to 25 kt late Sunday. Although the low may weaken, a tight pressure gradient will remain north of the stationary front draped over the northern waters into early next week, resulting in fresh to strong northeast winds and seas of 8 to 10 ft. Across the remainder of the zones from this weekend into early next week, a weak ridge axis along about 26N will support mainly gentle to moderate easterly winds through the period. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *For detailed zone descriptions, please visit: http://www.nhc.noaa.gov/abouttafbprod.shtml#OWF Note: gridded marine forecasts are available in the National Digital Forecast Database (NDFD) at: http://www.nhc.noaa.gov/marine/grids.php For additional information, please visit: http://www.nhc.noaa.gov/marine $$ .Forecaster Latto. National Hurricane Center.