000 AGXX40 KNHC 130755 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 355 AM EDT Thu Jul 13 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... An E to W ridge will follow 30N along the northern Gulf Coast through tonight. The ridge will then shift NW on Fri, re- orientating from N to S across the western gulf waters on Sat. The northern extension of a tropical wave currently over the far NW Caribbean and a broad inverted trough currently passing W through the Bahamas are merging and will give rise to a broad inverted trough over the SE Gulf by Fri morning. The trough will shift NW, and extend NE from 22N94W to near the Fl Big Bend on Sat, then continue shifting NW and extend across the N- central and NE waters on Sun with light to gentle winds prevailing throughout the gulf. Light to moderate SE return flow is expected to develop across the western Gulf by Monday night in response to developing low pressure over Texas and Mexico. An inverted thermal trough will develop over the Yucatan Peninsula during the late afternoons into the early evening hours, and move W-NW during the overnight hours, and dissipate over the SW Gulf by late each morning. Expect a moderate to fresh NE-E-SE wind shift, and seas to 5 ft, along the trough through tonight, then a gentle to moderate wind shift is forecast along the trough through Sun night, becoming a moderate to fresh shift again on Mon night. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... A tropical wave is moving into the Yucatan Peninsula from the far NW Caribbean. Atlc high pressure is weakening as low pres moves E from the United States mainland. This is resulting in diminishing trades across the S-central Caribbean. Expect strong nocturnal NE trades only within 60 nm of the NW coast of Colombia, and across the Gulf of Venezuela through Sun night. A second tropical wave is W of the Lesser Antilles near 66W. The wave is moving W around 15 kt and is triggering showers and thunderstorms near and just to the N of Puerto Rico and the Virgin Islands. This wave will reach the central Caribbean tonight and the western Caribbean on Fri night. High pressure to the N of the Caribbean will begin to rebuild on Monday. ..SW N ATLANTIC INCLUDING THE BAHAMAS... A broad low level trough currently centered along the Atlantic Coast of Florida will be accompanied by showers and thunderstorms as it continues W today and tonight. A tropical wave extending N from Puerto Rico to near 22N65W is generating showers and thunderstorms over Puerto Rico and the Virgin Islands. The wave will continue W through the upcoming weekend and spread the convection across the Bahamas and Old Bahama Channel Sat, and Sat night across the Bahama Channel. An E to W ridge extending from Bermuda to extreme NE Fl will shift N of the area as the troughs continue westward, then rebuild and meander from Bermuda to Port Canaveral on Sat through Mon. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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 McElroy. National Hurricane Center.