marine weather discussion NWS National Hurricane Center Miami FL 212 PM EST Thu Dec 14 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 dominates the basin extending from W to E along 24n. Recent scatterometer as well as buoy and ship data show gentle to moderate winds around the high with seas of 1-3 ft across the Basin.
A pre-frontal trough is forecast to slip S into the far northern Gulf waters this evening, with the actual cold front moving into offshore waters overnight tonight into early on Friday. Northerly winds will rapidly increase to fresh to near gale force behind the front by around daybreak on Friday, then will increase to minimal gale force offshore of Mexico, reaching to offshore of Veracruz Friday night. Seas will build to 8-14 ft W of the front with the strong to gale force winds. The front is forecast to stall from near Tampa Bay, Florida to 25n95w to 19n95w by late Friday night with models suggesting that broad and week low pressure will possibly developing along the boundary in the SW Gulf by early Saturday.
The low is then forecast to move northward into the NW Gulf through Sat evening with se-S flow on the eastern side of the low increasing to fresh to strong. The low will then move inland over eastern Texas through Sunday morning, where it will then linger along with broad troughing over the coastal plain into early next week. Atlc high pressure that ridges westward across the area will block the trough from proceeding eastward across the forecast waters.
...Caribbean Sea and tropical N Atlantic from 07n to 19n between 55w and 64w...
A frontal trough is over the western Caribbean Sea extending from just SW of Jamaica to central Panama. Ascat data from overnight last night showed fresh to strong northerly flow within 180 nm W of the trough axis, with gentle to moderate winds elsewhere W of the trough. Seas are 6-8 ft W of the trough where now moderate to fresh N-NE winds are present. Seas of 4-6 ft are elsewhere W of the trough. Moderate to fresh trades are E of the trough across the remainder of the Caribbean, with 4-5 ft seas, except for lower seas of 3-4 ft N of 15n E of 76w.
The trough will dissipate by late tonight, and the seas of 6-8 ft will subside to 5-7 ft. Meanwhile, the pressure gradient will tighten beginning over the S central Caribbean where trades will increase to fresh to strong, highest of the trades along and near the NW coast of coast of Colombia where seas will build to 7-10 ft. The gradient will continue to strengthen through the weekend and gale force winds are forecast to pulse NW of the Colombian coast Friday night, Saturday night, and Sunday night. Seas will build to 9-14 ft in S central portions with the highest of these seas near the coast of Colombia. These seas may possibly build slightly higher on Sunday night before lowering early next week.
The fresh to strong trades will expand in coverage during the weekend into early next week, covering the entire central and SW Caribbean Saturday night through Tuesday night, with plumes of fresh to strong winds also across the approach to the Windward Passage, in the Lee of Hispaniola and in the Lee of Cuba.
...SW N Atlantic including the Bahamas...
A cold front is slowing down from near 27n65w SW across the se Bahamas and to central Cuba. Relatively weak high pressure is behind the front. With high pressure ridging extending from the se Gulf of Mexico to across the central Bahamas in the wake of the front. Ascat scatterometer and surface observations indicate mainly gentle to moderate winds W of the front. Large northerly swell covers the NE waters, up to 8-14 ft which will decay through tonight, with seas of 4-7 ft elsewhere.
Winds will increase to the fresh category on the NW and N central waters as another weak frontal boundary moves by N of the area, with little impact initially to the waters S of 31n through Fri. The boundary is then forecast to drop S of 31n Friday night through Saturday night, with winds increasing to fresh to strong, and seas building to 8-10 ft N of 29n E of 77w. These conditions then shift to the far NE portion of the forecast waters on Saturday, and to E of those waters on early on Sunday.
High pressure will then build down from the N in the wake of the front, with ridging settling along 28n for the second half of the weekend into early next week. This should usher in fairly tranquil marine conditions across the basin for the start of next week.
.Warnings...Any changes impacting coastal NWS offices will be coordinated through AWIPS ii collaboration chat, or by telephone:
.Gulf of Mexico... .gmz017...W central Gulf from 22n to 26n W of 94w... Gale Warning Fri into Fri night. .Gmz023...SW Gulf S of 22n W of 94w... Gale Warning W of 96w.
.Caribbean Sea and tropical N Atlantic from 07n to 19n between 55w and 64w... .Amz031...Caribbean from 11n to 15n between 72w and 80w including Colombia basin... Gale Warning. Gale conditions possible Sat. Night. Gale conditions possible Sun. Night. Gale conditions possible Mon. Night.
.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 Aguirre. National Hurricane Center.