000 AGXX40 KNHC 101830 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 230 PM EDT Tue Oct 10 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... The most recent scatterometer data show gentle to moderate ESE winds across the Gulf with moderate to fresh easterly winds in the Straits of Florida due to the pressure gradient between a surface trough moving across the SE Gulf and high pressure to the north. Some shower activity is also noted related to this trough across the Straits of Florida and the Florida Keys. Expect east winds of 20 kt and seas to 7 ft across the Straits of Florida this afternoon and tonight. These marine conditions are forecast to persist on Wednesday with winds from the NE to E. Moderate to locally strong NE-E winds are noted west of the Yucatan Peninsula in association with a thermal trough. Otherwise, a weak ridge dominates the Gulf waters. A cold front will reach the NW Gulf this afternoon, and extend from SE Louisiana across the western Gulf W of 95W to near Tampico, Mexico tonight, and from Mobile, Alabama to near Veracruz, Mexico Wednesday morning. The portion of the front across the Gulf will then stall Wednesday afternoon and then gradually dissipate through Thursday night. High pressure building in the wake of the front along the eastern slopes of the Sierra Madre Mountains in Mexico will result in fresh to strong northerly wind across the west-central Gulf tonight, and NW-N winds across the SW Gulf on Wednesday. These winds will persist through Wednesday night, with building seas of 6-8 ft across the west-central Gulf, and 8-9 ft across the SW Gulf. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... Mainly light to gentle winds are blowing across the basin with the exception of moderate to fresh winds off the coast of Belize and in the Gulf of Honduras, and moderate to locally fresh NE winds in the lee of Cuba. A trough moving across the SW N Atlantic will support a weak pressure gradient across much of the area, with mainly gentle to moderate winds and seas generally under 4 ft through at least Thursday. Winds and seas will begin to increase across the eastern Caribbean early on Friday, with fresh to strong trade winds across the south-central Caribbean, including the Venezuela and Colombia basins by Friday night. Seas are forecast to build to 8-9 ft with these winds. A tropical wave is moving across the eastern Caribbean this morning generating some shower and thunderstorm activity over the NE Caribbean. Winds and seas could be higher near tstms. The wave will move over central Caribbean waters on Wednesday and over the western part of the basin on Thursday. Winds and seas will slightly increase behind the wave axis. ...SW N ATLANTIC INCLUDING THE BAHAMAS... A ridge dominates most of the forecast waters while a trough extends from 25N64W to near Puerto Rico. The pressure gradient between the trough and high pressure N of the area is already producing a large area of fresh to strong winds and seas of 8-11 ft, covering roughly the waters from 24N-30N between 60W-70W. Expect active weather in the form of scattered to numerous showers and thunderstorms with possible gusty winds and building seas with this trough, forecast to move WNW across the SW N Atlantic through Friday. However, winds and seas in association with this trough are expected to diminish to 20 kt or less with seas less than 8 ft Wed night into Thu morning, as high pressure N of area moves SE and weakens. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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 GR. National Hurricane Center.