000 AGXX40 KNHC 041807 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 207 PM EDT Fri Aug 4 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 trough extending along the Texas and Louisiana coasts will continue weakening and drift N inland today as an E to W ridge builds from Tampa Bay to NE Texas where it will meander through Sun. Expect considerable convection over the northern gulf waters well into tonight. A thermal trough will develop over the Yucatan Peninsula each evening, move slowly westward during the overnight hours, and dissipate over the SW Gulf each morning. Expect a moderate to locally fresh NE-E-SE wind shift, and 2-4 ft seas, along this trough through Mon, then guidance is suggesting a tighter pressure gradient that will support a fresh to locally strong wind shift. This tightening of the gradient will be associated with a tropical low expected to develop along a tropical wave over the NW Caribbean early next week. This system will cross the Yucatan Peninsula on Tuesday and produce heavy rainfall. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... A broad tropical wave is currently analyzed with an axis along 70W. Considerable convection is currently firing along and E of the wave axis, mainly between 14N and 17N S of Puerto Rico and Hispaniola. Thus, convection will be depicted in the weather grids for the next several days based upon the forecast positions of the wave. Scatterometer data shows fresh to strong strong trade winds over the Caribbean E of 80W, and recent buoy reports indicate seas of 8 to 9 ft in the Caribbean south of Puerto Rico and Hispaniola. The large areas of convection suggest strong to near gale force winds will accompany the wave. These conditions will pass to the W of the Caribbean late Tue. A strong tropical low associated with a tropical wave will approach 55W late Tue night. Environmental conditions will be favorable for tropical cyclone formation. ...SW N ATLANTIC INCLUDING THE BAHAMAS... A surface high is expected to develop today near 28N71W along an E to W ridge. The high will drift slowly N through Tue as a ridge extends WSW and later W to NE Florida. Moderate to locally fresh SW flow is expected N of the ridge through early Sun, then light southerly flow is expected. The northern portion of a tropical wave currently along 70W crosses just to the north of the Dominican Republic. Expect fresh to strong E trades across the waters S of 23N through early Sat, then strong E trades over a smaller area along the N coast of Hispaniola during the late afternoons and early evenings. A strong tropical low associated with a tropical wave will approach 55W late Tue night. Environmental conditions will be favorable for tropical cyclone formation. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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.