000 AGXX40 KNHC 270759 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 359 AM EDT Mon Mar 27 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... High pressure northeast of the region will support mainly moderate to fresh east to southeast winds across the southern Gulf and moderate southerly winds over the northern Gulf through Wednesday night. The exception will be attributed to fresh to strong northeast to east winds associated with a thermal trough moving westward from the Yucatan Peninsula and over the eastern Bay of Campeche each night. High pressure will build southward over the Bahamas by Tuesday night. At the same time, deepening low pressure will move over the southern plains with a cold front over the interior of Texas. This pattern will result in a tightening of the pressure gradient across the western Gulf beginning on Tuesday afternoon and through Thursday. The cold front associated with the deepening low pressure over the southern Plains is forecast to reach the northwest gulf portion early on Thursday, and move over the northern waters through Friday while weakening. However, southerly flow ahead of the front will increase to fresh to strong intensity mainly over the north-central and northeast gulf waters Thursday through Friday. Enough instability will be available in the environment ahead of the front for scattered showers and thunderstorms to likely form there. Some of them may contain brief gusty winds and possible frequent lightning at times. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... A weak pressure pattern with moderate winds will persist across the Caribbean through Tuesday as broad low pressure north of Hispaniola slowly moves northward then eastward away from the forecast waters of the Southwest North Atlantic zones. High pressure will build across the Bahamas by Tuesday night and persist there through Thursday before it begins to strengthen and slide eastward beginning on Thursday night. This will bring a slight increase in the trades across the Caribbean, with fresh to locally strong southeast winds developing across the Gulf of Honduras. The northerly swell that had been affecting the northern and central tropical North Atlantic has decayed allowing for seas to subside to less than 8 ft. Another northerly swell event associated with the aforementioned broad low press north of Hispaniola will propagate into the northern tropical North Atlantic Wednesday through Friday, but it appears that the bulk of the swell energy should just stay along the far northern boundary of the tropical North Atlantic zones where the induced 8 ft and greater seas may be seen. This scenario may possibly change in future forecasts pending on just how much time the low takes before it pulls far enough away from southwest North Atlantic forecast waters. ...SW N ATLANTIC INCLUDING THE BAHAMAS... Latest satellite imagery shows the center of the broad low pressure near 24N69W, moving slowly northward with a pressure of 1008 mb. An elongated surface trough extends from near 29N67W, through the low and to just north of Hispaniola. The pressure gradient between high pressure north of the region and the low pressure continues to support a large area of strong to near gale force winds north of the low, with gale force winds from about 90 nm to 240 nm northwest and north of the low center. Numerous showers and scattered thunderstorms are observed north of 25N between 57W and 68W. Recent altimeter data revealed seas of 12-18 ft within about 300 nm north of the low center, with a large area of 8-12 ft seas across the Atlantic zones south of 30N, east of the Bahama Islands. The forecast remains on track with the low continuing to slowly track northward into early this afternoon, before turning northeast while beginning to accelerate. The low will exit the northeastern zones Tuesday morning. Although the low center will be east of the northeastern zones on Tuesday, strong to near gale winds and seas of 8 to 14 ft will remain north of 25N, east 70W through at least Tuesday evening, except for higher seas of 12-18 ft north of 28N east of 67W. Winds will diminish to less than 25 kt over the northeast zones by Wednesday morning, with seas of 8-11 ft in northeast to east swell subsiding to 6-9 ft Wednesday night and to 5-7 ft on Thursday. Meanwhile, high pressure will build across the Bahamas by Tuesday night and remain centered there through Thursday, before it begins to slide eastward Thursday night through Friday in response to a weak cold front that is forecast by the models to move across the southeast United States. Fresh to strong southerly winds will develop over the northwest waters on Friday in advance of the front, with seas building to 6-8 ft. Southeast winds over the remainder of the western waters will increase to fresh category on Friday. Otherwise, the gradient associated with the high pressure will allow for generally gentle to moderate anticyclonic flow throughout the basin Wednesday through Friday with seas in the range of about 4-6 ft. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... .AMZ115...ATLANTIC FROM 27N TO 31N BETWEEN 65W AND 70W... Gale Warning through tonight. $$ *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 Aguirre. National Hurricane Center.