000 AGXX40 KNHC 291903 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 303 PM EDT Fri Sep 29 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 stationary front over the northern Gulf will slowly sag southward through Saturday, reaching from the Florida Big bend to offshore southern Texas Saturday night. The stationary front will then begin to dissipate from west to east on Sunday. Low pressure is forecast to develop along the dissipating western end of the stationary front over the northeastern Gulf on Sunday, while high pressure builds southeastward over the eastern United States. There is medium chance for the low to develop into a tropical cyclone as it moves westward over the northern Gulf Sunday into Monday. Regardless of how it develops, the pressure gradient between the low and the high to the north will support strong northeasterly winds over the northeast Gulf Sunday into Sunday night, with seas building as high as 8 ft based off the current forecast. Strong high pressure will continue to build northeast of the basin early next week which will support an expanding area of strong easterly winds over the eastern two thirds of the Gulf, which will build a large area of seas 8 to 10 ft over that portion of the Gulf basin. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... The combination of tropical wave energy over central America, a surface trough over the northwest Caribbean, and upper level diffluence over the region continues to support clusters of convection over the northwestern Caribbean. This pattern is forecast to persist over this area through this weekend. A tropical wave over the eastern Caribbean is interacting with an upper low to the east to produce widespread shower and thunderstorm activity over the Eastern Caribbean, Leeward Islands, and Puerto Rico. This wave and accompanying upper low will move westward to the central Caribbean this weekend, then the western Caribbean early next week, bringing with them unsettled weather. A frontal system entering the western Atlantic has weakened the subtropical ridge north of the basin slightly, and will result in mainly gentle to moderate trades over much of the Caribbean through early next week. The presence of the monsoon trough over the southwestern Caribbean will promote mainly light to gentle winds over that part of the basin the next several days. ...SW N ATLANTIC INCLUDING THE BAHAMAS... Large swell of 8 to 11 ft over the northwest zones from Maria well northeast of the area will shift east of the zones through tonight. An elongated surface trough extends from the northern Bahamas to the northwest Caribbean and is producing a large area of showers and thunderstorms over Florida and the forecast waters west of 75W. Forecast models continue to indicate an area of low pressure to develop near the east central Florida coast by Saturday, and meander just east of the north Florida coast into Sunday, before dissipating on Monday. The pressure gradient between this low and high pressure building southeast over the eastern United states will support strong to near gale force winds over the waters north of the low Sunday and Sunday night. After the low dissipates, the strong high to the north will continue to build over the eastern United States, which will support strong northeast to east winds over the waters N of 25N and west of 75W through early next week, with seas building to 8 to 10 ft. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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.