000 AGXX40 KNHC 180841 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 441 AM EDT Sat Mar 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... MODEL PREFERENCE: Global model consensus. Medium-high confidence. A ridge extends w across the northern gulf from a surface high meandering over the far ne waters. The high center will shift w to near 28N92W tonight with a ridge extending se across the Fl Straits. A weak cold front will pass e across the ne gulf waters tonight accompanied only a moderate w-nw-n wind shift. Moderate n flow forecast to the e of 87W on Sun evening, with locally fresh n flow developing within 60 nm of the w coast of Fl on Sun evening. These moderate to fresh n winds will clock to the ne late Sun night and spread w across the gulf waters to the s of 28N and e of 87W through early Mon. The surface high will shift back e along 28N to near 29N84W on Mon evening with the dominate ridge axis then extending sw to near Veracruz Mexico. The high should then meander over the ne waters through Wed. A thermal trough will develop late each afternoon over the Yucatan Peninsula, and shift w across the waters s of 22N between 90W and 93W during the overnight hours, and gradually lose identity along about 94W late each morning. Expect a ne-e- se 20-25 kt wind shift along the trough with seas building to 7 ft. Otherwise, moderate anticyclonic flow forecast across the gulf through Tue evening, with fresh se return flow developing across the nw waters on Wed night. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: Global model consensus. Medium confidence. A stationary front extending sw from Haiti to the border of Nicaragua and Honduras will gradually dissipate today, while accompanied by scattered showers. Fresh to strong ne flow is forecast to the w of the decaying front this morning, fresh ne winds then expected through Mon morning, with gentle to moderate ne flow forecast on Tue and Wed. A brief surge of strong ne to e winds expected along the s coast of the Dominican Republic this morning. Strong to near gale force trades forecast within 150 nm of the nw coast of Colombia at sunrise this morning then quickly diminishing throughout the day. Near gale conditions expected to develop tonight, then the pressure gradient will relax on Sun with strong ne winds forecast only within about 60 nm of the coast on Sun night, and only fresh nocturnal winds expected on Mon, Tue and Wed nights. Moderate to fresh trades forecast elsewhere through Sat morning, then mostly moderate trades forecast through Tue. Large n swell, in the form of 7-10 ft seas, will continue across the tropical waters to the n of 10N through tonight, then subside to less than 8 ft on Sun evening. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: Global model consensus. Medium confidence. A stationary front extends from 29N55W to Haiti. Strong ne winds continue to the s of 28N within 240 nm w of the front. The front will weaken today with the remnants drifting nw tonight accompanied by fresh ne flow within 180 nm nw of the frontal remnants. Expect a frontal trough from 29N55W to 26N69W to 22N75W early Sun. By then a cold will extend from 31N75W to central Florida accompanied by a strong sw-w-nw wind shift, and 8-11 ft seas, all to the n of 28N within 180 nm either side of the front. This cold front will merge with the remnants of the initial front along a position roughly from Bermuda to the Fl Straits late Sun. The merged front should reach from 31N59W to e Cuba on Mon, weaken to a frontal trough from 26N55W to the Windward Passage on Tue, with the remnants beginning to drift w on Tue night. Expect seas of 8 ft or greater to dip as far s as 26N across the waters e of the Bahamas in the wake of the cold front. Another cold front will move off the Fl coast on Tue night, and reach from bermuda to central Florida on wed 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 Nelson. National Hurricane Center.