000 AGXX40 KNHC 181740 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 140 PM EDT Tue Apr 18 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... Clusters of showers and thunderstorms are active across the western Gulf of Mexico this morning, ahead of a sharp mid to upper trough moving through the southern Plains and northeast Mexico. Strong gusts are possible near some of these thunderstorms. Similarly, a negatively tilted short wave trough is supporting scattered showers and thunderstorms over the far southeast Gulf, just west of Key West Florida. Fresh easterly flow is noted over the Straits of Florida and the eastern Gulf, between high pressure over the western Atlantic and lower pressure farther south. The regular overnight trough off the west coast of Yucatan is slowly dissipating over the southwest Gulf. Seas generally 2 to 4 ft across the Gulf. The sharp upper trough will become cutoff over the central Gulf Wednesday then dissipate, but support scattered convection over the south central Gulf through Wednesday night. Otherwise, little change is expected into Saturday. Areas of fog are possible by A weak cold front will move off the Texas coast late Saturday and reach from the western Florida Panhandle to the southwest Gulf by late Sunday followed by strong northerly winds. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... Upper jet dynamics are supporting scattered showers and thunderstorms across the northwest Caribbean. A recent scatterometer pass indicated fresh to strong winds in a small area off Cabo Beata along the southern coast of the Dominican Republic. Gentle to moderate breezes are noted elsewhere. Plumes of northerly swell to 8 ft are pushing through Atlantic passages in the Leeward Islands and the Mona Passage. Elsewhere seas of 4 to 6 ft are noted, except 3 to 5 ft in the northwest Caribbean. Northerly swell is also propagating through the Atlantic waters off the Leeward Islands, and will reach farther south to off the Windward Islands later today. Northerly swell 8 ft or greater will persist east of the Leeward and Windward Islands through Thursday before decaying below 8 ft. Localized pulses of fresh to strong trade winds are possible through the Windward Passage, off Cabo Beata and off Colombia trough the next several days. Otherwise little change is expected. ...SW N ATLANTIC INCLUDING THE BAHAMAS... 1024 mb high pressure centered near 29N67W dominates the forecast waters. Latest scatterometer and surface data depict fresh to strong winds south of 22N off the northern coast of Hispaniola, including the approaches to the Windward Passage. Gentle to moderate breezes persist elsewhere. Recent buoy observations and scatterometer data indicate 8 to 10 ft seas south of 24N east of the Bahamas and Turks/Caicos Islands in northerly swell. Global wave model initializations appear too low with regard to this swell, and the near term forecast is slightly above guidance as a result. The area of swell in excess of 8 ft will decay below 8 ft and propagate south of the area through late Wednesday. Little change is expected through the remainder of the week. Southerly winds will increase off northeast Florida by late Sunday ahead of a cold front approaching from the west. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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 Christensen. National Hurricane Center.