000 AGXX40 KNHC 150852 CCA MIMATS Marine Weather Discussion...corrected NWS National Hurricane Center Miami FL 401 AM EDT Tue Aug 15 2017 Corrected SW N Atlantic including the Bahamas section to include motion with Gert 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... The main feature continues to be the western extension of the Atlantic sub-tropical ridge that reaches across the central Gulf. The associated anticyclonic flow consists of light to gentle winds in the basin as confirmed by current buoy observations and by an Ascat pass from 0308Z last night. The pressure gradient will tighten in the far western part of the Gulf beginning today due to the interaction between deepening low pressure in northern Mexico and W Texas and the ridge that is in place in the Gulf. This is expected to increase the southerly winds in some areas of the western Gulf to the moderate to fresh range, with seas building to around 6 ft in some spots in those areas of the Gulf. These winds are forecast to begin to diminish late on Thursday and through Saturday as the ridge lifts N to the northern Gulf. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... A tropical wave has entered the eastern Caribbean, and as of 06Z it along 66W/67W, moving westward at 15-20 kt. The wave will move across the remainder of the eastern Caribbean through this morning, the central Caribbean by early on Wednesday, then the western Caribbean through Friday before moving inland Central America late on Friday. A tightening of the pressure gradient will accompany this wave, bringing an increase to the trades across much of the eastern and central Caribbean as it moves quickly across those sections of the Caribbean. Expect scattered showers and isolated thunderstorms along and near the wave. A broad tropical wave will move quickly through the Tropical N Atlantic waters today through tonight, then across the eastern Caribbean from late Wednesday afternoon through Thursday night, and across the central Caribbean Friday and Friday night, and the western Caribbean Saturday. Scattered to numerous showers, some with gusty winds, are expected also with this wave. Scattered showers and thunderstorms are expected to develop in the far SW Caribbean today with the aid of low-level speed convergence. This activity should pulse from time to time through the forecast period. ...SW N ATLANTIC INCLUDING THE BAHAMAS...corrected Hurricane Gert was located along the northern most portion of the offshore waters boundary at a position of 31.2N 72.3W at 03Z, with maximum sustained winds of 65 kt with gusts to 80 kt. It was moving N at 7 kt. Gert is forecast to continue to pull away from the forecast waters through today as it intensifies. Tropical storm conditions will linger over a portion of the northern section of zone AMZ 113 early this morning, N of 30N between 71W and 73W, then become strong SW to W winds over the NE portion of that zone later this morning and into the afternoon. These winds will slowly diminish during the afternoon and evening, with associated seas to subside. In the wake of Gert, the central Atlantic sub-tropical ridge will build westward along 27N through late on Wednesday, before shifting slightly N to near 28N Thursday through Friday night and is forecast to change little through Saturday. The northern part of a strong tropical wave, that will be interacting with central Atlantic ridge, is expected to increase the winds and sea heights in the far southeastern waters of the basin, namely to the S of 22N near the Virgin Islands and Puerto Rico beginning this evening. A slight lull in these winds and seas is expected on Wednesday afternoon before they increase again on Wednesday night and diminish on Thursday afternoon. Guidance indicates that easterly winds begin to increase again late Thursday night over these same waters and diminish on Friday afternoon. As yet another large tropical wave or low pressure system moves through the Tropical N Atlantic waters, the pressure gradient is expected to tighten over zone AMZ 127 on Friday night and into Saturday. The wave axis passing across that zone is expected to be accompanied by a sharp NE to SE wind shift of moderate to fresh winds along with waveheights building to much higher ranges, perhaps around the 8-10 ft range. The wind/wave forecast will carry a fair amount of uncertainty in the latter periods for the SE waters of the basin as global models depict a varying degree of solutions with respect to how features will evolve from the tropical far eastern Atlantic, and that will eventually affect to some degree, these waters. Stay tuned to future updated text forecasts as well as updated NDFD forecast data. E winds will pulse to fresh, maybe with brief instances to strong, between the SE Bahamas and Hispaniola in the afternoons and at night through the forecast period. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... .AMZ113...ATLANTIC FROM 27N TO 31N BETWEEN 70W AND 77W... Tropical Storm Warning N of 30N between 70W and 73W early this morning. $$ *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.