000 AGXX40 KNHC 180835 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 435 AM EDT Fri Aug 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... 1018 mb high pressure centered near 27N87W along ridge extending across the northern Gulf is maintaining light to gentle breezes and slight seas over the north central and northeast Gulf, and gentle to moderate winds with 2 to 3 ft seas elsewhere. An upper is low centered over the Cay Sal area of the Bahamas near the eastern entrances to the Straits of Florida, drifting west into the southeast Gulf. A few thunderstorms are on the leading edge of the upper low, over the southeast Gulf, and will accompany the upper low as it drifts across the Gulf and reaches the Texas coast by late Tue. Little change is expected otherwise until mid week when what will likely be the remnants of Tropical Storm Harvey, currently east of Barbados, will cross the Yucatan peninsula. Most global guidance continues to be in good agreement showing the remnant low of Harvey weakening as it passes the Yucatan peninsula, but it is a little early to say with conviction what the intensity will be at that time. Please continue to refer to http://hurricanes.gov for more information on Harvey. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... At 0600Z, T.S. Harvey is centered about 80 nm east of Barbados, moving west at 16 kt, with 35 kt sustained winds and gusts to 45 kt. Numerous showers and scattered thunderstorms associated with Harvey are moving across the Windward Islands. Harvey is expected to continue westward across the central Caribbean through Sun, grazing Cabo Gracias a Dios in eastern Honduras as a strong tropical storm by Mon afternoon, then continuing through the northwest Caribbean reaching Belize by Tue afternoon. Harvey will remain relatively compact system, with an envelope of strong winds and seas 8 to 12 ft within 120 nm of the center on the northern semicircle. See http://hurricanes.gov for more information on Harvey. Ahead of Harvey, a tropical wave currently between Haiti and the central coast of Colombia will follow an upper low across the western Caribbean through Sat, accompanied by a few showers and thunderstorms across mainly the northwest Caribbean. Associated convection is currently ongoing over the Windward Passage and across the southern peninsula of Haiti. A scatterometer pass from 03 UTC indicated fresh to strong northeast winds in the southern lee of Cuba east of 80W ahead of the approaching tropical wave. ...SW N ATLANTIC INCLUDING THE BAHAMAS... A large and well defined upper low centered over the Cay Sal area of the Bahamas is moving westward and supporting scattered convection over portions of the northern Bahamas and near the Turks and Caicos Islands. Fresh easterly winds follow the tropical wave over the waters south of 22N and west of 70W. A ridge extends along roughly 29N, and fresh east winds will expand across the waters south of 25N with locally stronger winds near the coast of Hispaniola through today into Sat as Harvey passes south of the region through early next week. A second feature...an area of low pressure well to the southeast in the tropical Atlantic is moving WNW toward the region. Some potential exists for this low to develop into a tropical cyclone during the next couple of days as it approaches the area. Strong upper level winds may weaken it before it crosses 65W north of Puerto Rico by early Sun. This still will bring strong winds and building seas to the area south of 25N from Sun through mid week. A ridge along roughly 28N will move little through Sun then shift slowly northward early next week, maintaining light to gentle breezes into early next week north of 28N, with short period southeast swell of 4 to 6 ft. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... .AMZ021...CARIBBEAN FROM 15N TO 18N BETWEEN 72W AND 80W... Tropical Storm Warning Sat night. .AMZ031...CARIBBEAN FROM 11N TO 15N BETWEEN 72W AND 80W INCLUDING COLOMBIA BASIN... Tropical Storm Warning Sat night. .AMZ033...CARIBBEAN S OF 15N BETWEEN 64W AND 72W INCLUDING VENEZUELA BASIN... Tropical Storm Warning tonight into Sat night. .AMZ035...OFFSHORE WATERS WINDWARD ISLANDS INCLUDING TRINIDAD AND TOBAGO... Tropical Storm Warning today into tonight. .AMZ037...TROPICAL N ATLANTIC FROM 07N TO 15N BETWEEN 55W AND 65W... Tropical Storm Warning early today into today. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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 Christensen. National Hurricane Center.