590 AGXX40 KNHC 290759 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 359 AM EDT Sun Jul 29 2018 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 Atlantic high pressure extends a ridge southwestward across the Florida peninsula into the eastern part of the Gulf. The associated gradient is allowing for light to gentle anticyclonic winds to exist throughout. The buoy observations along with recent satellite-derived waveheights data reveal seas in the 1-3 ft over the entire basin. A thermal trough will continue to emerge off the western Yucatan Peninsula each night and move across the eastern Bay of Campeche during the forecast period, with associated winds increasing to locally fresh near the trough. Seas will build a little higher over the eastern Bay of Campeche, to the range of 3-4 ft, beginning Mon night. A ridge will continue to dominate the Gulf region with little change in the weather pattern through the middle part of next week. A cold front will approach the far northwestern Gulf Tue, and move across those waters Wed. Model guidance is depicting that the front will be driven by yet another rather strong deep- layer trough for this time of year that will swing east- southeast from the Great Plains to the southeastern United States at that time. The models indicate that the front will lift back N to over eastern Texas as a warm front on Wed night, then push eastward over the NW gulf waters as a weakening trough on Thu. Expect scattered showers and thunderstorms, some possibly with gusty winds and slightly higher seas, to increase over the northwestern section of the Gulf Tue through Thu. Isolated showers and thunderstorms may occur elsewhere over the Gulf through Wed. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... A tropical wave that was over the western Caribbean yesterday has moved inland Central America. In its wake, plenty of deep layer moisture lingers over the western and N-central Caribbean. Latest Satellite imagery shows scattered to numerous showers and thunderstorms over the waters north of 16N and west of Jamaica. Winds and seas may be higher near this activity. Central Atlantic high pressure ridging has nudged some to the the southwest over the northern part of the seas to the west of another tropical wave that has its axis near 70W as of 06Z. This wave will move across the central Caribbean through tonight and across the western Caribbean late Mon afternoon through Wed. Yet another tropical wave, presently moving through the eastern section of the tropical N Atlantic zones will approach the Lesser Antilles this evening, and move across the eastern Caribbean through early Tue, then across the central Caribbean later on Tue through Tue night, and the western Caribbean Wed through Thu night. The synoptic set-up of an upper-level low that is presently located over Haiti slowly moving in a westward motion towards eastern Cuba by Mon evening, to more in a west to west-southwest motion between Cuba and Jamaica Tue and Tue night and along or near 20N Wed through Thu night and while at the same time as the tropical waves trek across the central and western sections of the basin during the upcoming week, expect plenty of atmospheric instability to lead to scattered to numerous showers and thunderstorms over most of the zones in the north-central and northwestern Caribbean during those next few days. Otherwise, the pressure gradient between strong central Atlantic high pressure and broad low pressure over northern Colombia and the far southwestern Caribbean will maintain strong northeast to east winds along the coast of NW Colombia and NW Venezuela each night through Tue night, then mainly fresh winds with locally strong winds on Wed. Northeast to east winds are pulsing to near gale force along the coast of Colombia and to within 90 nm of that coast early this morning, but are forecast to diminish to just below gale force at or shortly after 12Z this morning. These winds are then forecast to pulse back up to near gale force Mon night and Tue night as passage of the waves across the central Caribbean will help enhance the gradient further to induce the northeast to east trades to reach near gale force along the coast of Colombia and over the far southwestern Caribbean waters. Fresh trade winds will prevail elsewhere across the central Caribbean, with moderate to fresh east winds over the eastern Caribbean, and gentle to moderate east-southeast winds over the western Caribbean. East winds will pulse to strong intensity over the Gulf of Honduras at night through Thu. ...SW N ATLANTIC INCLUDING THE BAHAMAS... Ample atmospheric deep layer moisture is entrenched over the western section of the forecast waters. The combination of a deep layer trough over the southeastern United States and this moisture will continue to set the stage for scattered to numerous showers and thunderstorms to remain quite active over waters west of about 75W. This activity is progged by moisture guidance from the models to continue into the middle part of the upcoming week. An upper-level low, the same feature as described above under Caribbean Sea and tropical N Atlantic, is noted over Haiti. The bulk of its associated shower and thunderstorm activity is over the northwestern and N central Caribbean waters. Only isolated showers and thunderstorms are seen from along and near the coast of Hispaniola to near 26N and between 67W-74W. This activity is moving to the northwest. This activity will continue in the general direction of the Bahamas, or just to the northeast of the island chain through Mon. High pressure ridging from the central Atlantic will extend to central Florida through Tue before lifting north of 31N by Thu. Fresh to occasionally strong east winds are expected just N of Hispaniola through Thu. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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 Aguirre. National Hurricane Center.