000 AGXX40 KNHC 020810 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 310 AM EST Sat Dec 2 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... An frontal boundary in the form of a surface trough extends from the Florida Panhandle near 30N84W to 28N90W to E of Brownsville near 25N93W. A NW-SE oriented surface trough extends from the NW Gulf near 24N93W to the Yucatan peninsula near 19N90W. Gentle to moderate winds are observed over almost all of the basin, with mainly moderate NE-E winds over the far SE waters. Seas range between 2 and 4 ft based on buoy observations and the latest satellite-derived sea height data. The old frontal boundary will weaken and dissipate during the next day or so as it moves slowly SE. The trough will migrate SW across the western Gulf to the coast of Mexico by this evening. High pressure will then build across the area this weekend into early next week. Wind speeds and sea heights are expected to change little through Sun, then model consensus calls for winds of 15-20 kt and seas building to between 4 and 6 ft by Monday evening, particularly across the SE waters. This will be the result of a tighter pressure gradient between high pressure parked over the SE United States and a low pressure trough along the coast of Mexico. Southerly return flow will also increase to 15-20 kt across the NW and west-central waters on Mon, ahead of the next cold front forecast to enter the gulf region late on Tue. Fresh to strong northerly winds and building seas are expected in the wake of the front. Model guidance suggests winds along the coast of Mexico near Tampico and Veracruz could reach gale force on Wed and Thu. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... The most recent ASCAT data indicates the presence of broad cyclonic flow over the western half of the Caribbean. A trough extending over the eastern Caribbean from 12N60W to 18N64W will drift slowly west and weaken the next couple of days. Convergent low-level winds on the east side of the trough are generating isolated thunderstorms between 13N and 17N between 60W and 64W. Moderate to fresh trades will continue over the south-central Caribbean through Sunday, then increase to fresh to strong speeds while expanding in coverage Monday through Tuesday. Fresh NE winds to the SW of Cuba will increase to mainly strong speeds Sunday night through Tuesday while spreading southwestward over the NW Caribbean waters. These stronger winds will be the result of high pressure building eastward over the western Atlc from the eastern United States. ...SW N ATLANTIC INCLUDING THE BAHAMAS... Developing 1010 mb low pres is centered over the NE waters near 26N62W. A developing stationary front extends ENE from the low to a secondary low centered near 28.5N50W, then continues as a warm front to 26N45W. Winds of 20 kt and seas to 9 ft in NE swell are noted within about 240 N of the trough and stationary front. The low will deepen and quickly move NE to near 30N45W by this evening, then to near 31N49W by Sun morning. The associated frontal boundary will pass across the SE waters during the upcoming weekend. As the low pressure exits the forecast area, high pressure will build E in its wake. This system will generally maintain moderate to locally fresh NE winds over the area through Mon. A tighter pressure gradient will bring and increase of easterly winds over much of the central and southern waters late Mon through Tuesday night. By Tue morning, marine guidance suggests E winds of 20-25 kt and seas of 8-9 ft across the waters E of the Bahamas. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... .GMZ017...W CENTRAL GULF FROM 22N TO 26N W OF 94W... GALE CONDITIONS POSSIBLE Tue night into Wed. .GMZ023...SW GULF S OF 22N W OF 94W... GALE CONDITIONS POSSIBLE Wed into Wed night. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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 McElroy. National Hurricane Center.