000 AGXX40 KNHC 220715 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 315 AM EDT Sat Apr 22 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 short-wave trough is supporting an area of showers with embedded thunderstorms across the southeast Gulf and parts of the Florida Keys. Winds and seas could be higher near thunderstorms. Surface data indicate the presence of a trough across this area, extending from the SE Gulf across the Yucatan Channel into the NW Caribbean. The remainder of the Gulf waters is under the influence of a ridge. Gentle to moderate east to southeast flow is noted across much of the area, with the exception of moderate to fresh winds across the SE Gulf, on either side of the trough axis, and fresh to locally strong winds across the Straits of Florida. A weak surface low pressure is forecast to form over the SE Gulf, along the trough axis, later today. Then, the low pressure is expected to migrate to the northeast across the southern Florida peninsula through Sunday night. This will occur ahead of a cold front moving off the coast of Texas late today. Fresh to strong northerly winds are expected behind the front, with seas building to 6-8 ft across the west-central waters on Sunday. The front will extend from the Florida Panhandle to near Tampico, Mexico by Sunday morning, and from Tampa Bay, Florida to the northern Yucatan Peninsula Monday morning, pushing SE of the Gulf by late Monday. A second weak front will shift eastward over the northern Gulf Monday, followed by building high pressure behind the fronts allowing gentle breezes and slight seas early next week. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... As previously mentioned, a trough extends across the SE Gulf of Mexico and the Yucatan Channel into the western Caribbean. A relatively tight pressure gradient between the trough and high pressure located over the SW N Atlantic is supporting fresh to locally strong easterly winds across the Straits of Florida, and in the lee of west and central Cuba based on the most recent scatterometer data. A diffluent pattern aloft is helping to induce convection over the north-central Caribbean, including the regional waters of the Cayman Islands, Jamaica and eastern Cuba. This tropical moisture will lift NE over the next 12-24 hours as a weak low pressure develops over the SE Gulf. In addition, winds will veer to the SE and S over the western Caribbean today due to the presence of this developing low. Then, winds will turn light and variable on Sunday as the low lifts NE. Expect NW winds of 15 kt across the Yucatan Channel and the far NW Caribean by Sunday evening, persisting through Monday evening in association with a weakening cold front entering the NW Caribbean by late Monday. Moderate to fresh trade winds over the eastern Caribbean and tropical north Atlantic west of 55W will continue into early next week south of high pressure located northeast of the Bahamas. These winds will weaken into Tuesday as the high pressure dissipates. Northeast swell will move into Atlantic passages in the Leeward Islands and through the Mona Passage later today through early next week with seas to 7 ft. ...SW N ATLANTIC INCLUDING THE BAHAMAS... High pressure of 1019 mb located near 29N68W extends a ridge across the forecast region, maintaining gentle to moderate easterly winds over much of the area. Mainly moderate to fresh E-SE winds are noted around the SW periphery of the high, with fresh to locally strong winds between the central Bahamas and eastern Cuba per scatterometer data. Seas are generally 5 to 7 ft east of the Bahamas based on buoy observations and an altimeter pass. Northeast swell of 6 to 8 ft will move into the region south of 27N from late today through early next week. The high pressure will move to a postion near 30N63W in about 24 hours. Southerly winds will increase to 15-20 kt off northeast Florida by late Sunday ahead of a cold front approaching from the west accompanied by a developing low pressure moving from the SE Gulf to off the Carolina Coast. The front is forecast to enter the forecast region by late Sunday night, and extend from 31N75W to central Cuba by Monday night. Southerly winds ahead of the front will further increase to 20-30 kt Monday through Tuesday across the waters E of the Bahamas, with building seas of 8-12 ft. This will be the result of a tight pressure gradient between the front and a high pressure center located east of the forecast area. The front will stall and dissipate from west of Bermuda to eastern Cuba through Tuesday. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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 GR. National Hurricane Center.