000 AGXX40 KNHC 301908 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 208 PM EST Thu Nov 30 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 frontal trough is over the NW waters. A NW-SE oriented surface trough extends from the NW Gulf to the Yucatan peninsula. The most recent scatterometer pass indicated the wind shift associated with the trough axis. Mainly light to gentle winds are noted over the gulf waters, with seas are generally under 5 ft based on altimeter data and buoy observations. A trough is forecast to persist over the western half of the gulf through Sun while drifting westward. High pressure will then build across the area this weekend into early next week. Little change in winds and seas are expected through Sun. Latest marine guidance suggests increasing winds of 15-20 kt and building seas of 6 or 7 ft on Monday, particularly across the NW and SE waters. This will be the result of a tighter pressure gradient across the area. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... A broad trough prevails over the western Caribbean. Latest scatterometer data provided observations of fresh to strong winds over the south-central Caribbean and gentle to moderate winds elsewhere across the Caribbean as well as the tropical N Atlantic forecast zones. Seas are in the 7-9 ft range in the south-central Caribbean, 3-5 ft elsewhere over the Caribbean, and 5-6 ft over the tropical N Atlantic forecast zones. The trough will linger over the western waters though the weekend into early next week. The area of fresh to strong winds will continue today before diminishing Friday. By Sat night, expect increasing winds and building seas in the lee of Cuba, then on Sun night winds will begin to increase across the Windward Passage and the south-central Caribbean. This will be associated with a building high pressure N of the area. ...SW N ATLANTIC INCLUDING THE BAHAMAS... A low pressure has developed over NE waters. As of 1200 UTC, the low of 1013 mb is centered near 27N69W with a trough extending SW to near 20N74W. An area of fresh to locally strong winds is noted within 150 nm NW semicircle of low center with seas to 9 ft. The low pressure is forecast to move eastward over the next 24 hours, reaching a position near 27N63W by Fri morning. Fresh to locally strong NE winds are also noted just off SE Florida due to the pressure gradient between the low and high pressure over the SE CONUS. As the low pressure exits the forecast area, high pressure will build in its wake. By late Fri, mainly moderate to fresh N-NE winds will dominate the area, with seas of 4-6 ft E of the Bahamas, and 2-4 ft W of the Bahamas, with the exception of 4-6 ft across the Straits of Florida due to persistent moderate to fresh NE winds. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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 GR. National Hurricane Center.