000 AGXX40 KNHC 161825 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 225 PM EDT Tue May 16 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 surface ridge extends along the U.S. Gulf coast states anchored by a 1017 mb surface high centered near 30N90W. Light to gentle easterly winds are E of 90W, and gentle to moderate return flow is W of 90W. Seas are 1 to 3 ft prevail across most of the Gulf, except 3 to 5 ft mainly N of 26N W of 95W. The pressure gradient will increase as an elongated troughing inland over central Texas deepens. As a result, return flow will increase in the NW Gulf tonight, reaching fresh to strong offshore of Texas, with seas building to 7 to 9 ft. The gradient will then weaken slightly by Wednesday afternoon allowing the strong winds to diminish. Moderate to fresh E to SE flow will dominate the basin Wednesday night through the end of the week, except locally and occasionally strong through the Straits of Florida and NW of the Yucatan Peninsula. The elongated surface troughing will move from the NW Caribbean into the SE and eventually central Gulf Friday night through Saturday. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... A 1010 mb surface low was analyzed near 20N82W. A surface trough extends from this low to 16N82W to 11N83W. A mid to upper-level trough is deepening just to the NW of these surface features, with active convection present across eastern Cuba, Jamaica, and western Hispaniola, as well as the approach to the Windward Passage. The northern extent of a tropical wave is exiting near the northwest coast of Venezuela, enhancing convection south of 13N between 65W-71W. Moderate E to SE flow prevails across the area N of 11N and E of the trough axis along with 4 to 7 ft seas, with gentle to moderate winds elsewhere along with 2 to 4 ft seas. Winds and seas may be higher though near the area of deep convection today. The trough/low are forecast to linger across the same general area through the majority of the week before moving W to NW Friday through early Saturday. Winds to the E of these features are forecast to increase to fresh to strong this afternoon and through the end of the forecast period, while moderate trades will prevail elsewhere. Seas will build to 7 to 9 ft within the area of increasing winds, and 4 to 7 ft elsewhere. In the Tropical N Atlantic, moderate to fresh trades and 5 to 7 ft seas will prevail through the next several days. ...SW N ATLANTIC INCLUDING THE BAHAMAS... An old frontal boundary is becoming diffuse from near 30N64W to 27N80W. High pressure ridging extends along 24N to the E of the front, with new high pressure building in from the NW to the W of the front. Mainly gentle to moderate easterly winds prevail across the offshore waters basin. Seas are 2 to 4 ft W of 70W, except 2 ft or less W of the Bahamas, and 4 to 7 ft E of 70W. Ample moisture is present SE of the front with clusters of scattered thunderstorms. This activity will likely continue through the day. The ridging both NW and SE of the front will shift ENE to NE through Wednesday while the front lays down along 27N and weakens. Moderate to fresh easterly flow will prevail once this occurs, except increasing to fresh to strong from N of Hispaniola to across the Bahamas and through the Straits of Florida as surface troughing extends to the N and NE from the Caribbean Sea. The troughing will gradually shift W and NW by the end of the week with moderate to fresh E to SE flow prevailing basin-wide thereafter. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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 ERA. National Hurricane Center.