000 AGXX40 KNHC 240720 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 320 AM EDT Mon Jul 24 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 typical thermal trough will develop over the Yucatan Peninsula each late afternoon-evening through midweek, before pushing offshore into the SW Gulf each night, drifting westward during the overnight hours, then dissipating over the SW Gulf each morning. A surge of mainly fresh NE winds will accompany this trough while seas briefly build to 4 to 6 ft. The strongest surge of winds is occurring right now, and will diminish through sunrise. A weaker thermal trough is expected by the end of the week. Otherwise, a ridge axis extends from the Texas coastal plains across the NW Gulf to across SW Florida. Recent observations show moderate to locally fresh return flow in the NW Gulf, with gentle to moderate anticyclonic flow elsewhere across the basin. Seas are up to 3 to 5 ft in the NW Gulf, 2 to 4 ft in the SW Gulf, and 2 ft or less elsewhere. These conditions are forecast to persist through Tuesday night. The pressure gradient will slacken thereafter as a trough or weak front passes into the NE Gulf. Gentle winds and seas of 2 ft or less will then prevail across the basin by the end of the week. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... Recent observations indicate the continued presence of fresh to strong trades in the central Caribbean due to a locally tight pressure gradient, where seas are also building up to 8 to 11 ft. Moderate to fresh trades prevail elsewhere, along with seas of 3 to 5 ft, except 2 to 3 ft in the lee of Cuba. The area of fresh to strong trades will expand westward to near 82W by Tuesday morning in the wake of a departing tropical wave, as high pressure N of the area of the Atlantic builds westward. The area of fresh to strong trades will then become confined to the S central waters by the end of the week as the Atlantic ridge weakens. ...SW N ATLANTIC INCLUDING THE BAHAMAS... Ridging extends from 1022 mb high pressure near 28N61W to the Space Coast of Florida. Moderate to locally fresh anticyclonic winds exist around the outer periphery of the ridge from N of Hispaniola, to between Florida and the Bahamas, to offshore of the Carolinas, where seas are 3 to 5 ft. Gentle to moderate anticyclone winds are found elsewhere, along with seas of 2 to 4 ft. Little change in these conditions is expected through early Tuesday. A trough will then move in from the E-SE through mid- week, weakening the ridge with the parent high lifting N of the area. This will allow for a slackening pressure gradient with winds diminishing, and seas subsiding slightly through Thursday. A frontal system is forecast to move through the SE United States by the end of the week which will increase the pressure gradient, especially across NW portions where winds will increase to fresh Friday night. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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 Lewitsky. National Hurricane Center.