846 FZNT31 KNHC 181507 OFFN20 Marine Weather HF Voice Broadcast NWS National Hurricane Center Miami, FL 1107 AM EDT Tue Mar 18 2025 Marine Weather HF Voice Broadcast for the Tropical N Atlantic from 07N to 19N W of 55W, the N Atlantic from 19N to 31N W of 55W including the Bahamas, and the Caribbean Sea. Seas given as significant wave height, which is the average height of the highest 1/3 of the waves. Individual waves may be more than twice the significant wave height. Synopsis for Caribbean Sea and Tropical N Atlantic from 07N to 19N W of 55W .SYNOPSIS...Fresh NE winds and rough seas following the tail of a cold front that extends from the Windward Passage to the offshore waters of Nicaragua will diminish to moderate speeds late in the afternoon as the frontal boundary continues to weaken before dissipating tonight into early Wed. However, building high pressure in the wake of the front N of the area will lead to the development of pulsing fresh to strong NE winds in the lee of Cuba and the Windward Passage from this evening through Wed evening. In the south-central and portions of the SW Caribbean, fresh to strong NE to E winds will prevail through the weekend, increasing in areal coverage Fri. Otherwise, high pressure will build near the Bahamas over the weekend and trade winds will increase across the region, with near gale-force winds developing offshore Colombia Sat night along with rough seas. Looking ahead, the tail of a cold front will enter the NW Caribbean early Fri and dissipate Fri evening. NW Caribbean W of 85W .THIS AFTERNOON...NE winds 10 to 20 kt. Seas 6 to 8 ft. .TONIGHT...NE winds 10 to 15 kt. Seas 5 to 7 ft. .WED...E winds 10 to 15 kt. Seas 4 to 5 ft. .WED NIGHT...E winds 10 to 15 kt. Seas 4 to 5 ft. .THU...NE winds less than 10 kt. Seas 3 to 4 ft. .THU NIGHT...NE winds less than 10 kt, increasing to 10 to 15 kt after midnight. Seas 3 to 4 ft. .FRI...NE winds 10 to 15 kt. Seas 4 to 6 ft. .FRI NIGHT...E winds less than 10 kt, increasing to 10 to 15 kt after midnight. Seas 4 to 6 ft. .SAT...E winds 10 to 15 kt. Seas 4 to 6 ft. .SAT NIGHT...E winds 10 to 20 kt. Seas 3 to 5 ft. Caribbean N of 15N between 72W and 85W .THIS AFTERNOON...NE winds 10 to 20 kt. Seas 4 to 6 ft. .TONIGHT...NE winds 10 to 20 kt. Seas 4 to 6 ft. .WED...E winds 10 to 20 kt. Seas 4 to 6 ft. .WED NIGHT...E winds 10 to 15 kt. Seas 3 to 5 ft. .THU...E winds 10 to 15 kt. Seas 3 to 5 ft. .THU NIGHT...NE winds 10 to 15 kt. Seas 3 to 5 ft. .FRI...NE winds 10 to 15 kt. Seas 3 to 5 ft. .FRI NIGHT...NE winds 10 to 20 kt. Seas 4 to 6 ft. .SAT...E winds 10 to 20 kt. Seas 5 to 7 ft. .SAT NIGHT...E winds 10 to 20 kt. Seas 5 to 7 ft. Caribbean from 11N to 15N W of 72W .THIS AFTERNOON...NE winds 10 to 15 kt. Seas 3 to 5 ft. .TONIGHT...NE winds 10 to 15 kt. Seas 3 to 5 ft. .WED...NE winds 10 to 20 kt. Seas 3 to 5 ft. .WED NIGHT...NE winds 15 to 25 kt within 90 nm of coast of Colombia, and NE 10 to 20 kt elsewhere. Seas 4 to 6 ft. .THU...NE winds 10 to 20 kt. Seas 5 to 7 ft. .THU NIGHT...NE winds 10 to 20 kt. Seas 5 to 7 ft. .FRI...NE winds 10 to 20 kt. Seas 6 to 8 ft. .FRI NIGHT...NE winds 15 to 25 kt. Seas 6 to 9 ft. .SAT...NE winds 15 to 25 kt. Seas 7 to 10 ft. .SAT NIGHT...NE winds 15 to 25 kt. Seas 8 to 11 ft. SW Caribbean S of 11N .THIS AFTERNOON...N winds 10 to 15 kt. Seas 4 to 6 ft. .TONIGHT...N winds 10 to 20 kt. Seas 4 to 6 ft. .WED...NE winds 10 to 20 kt. Seas 4 to 6 ft. .WED NIGHT...NE winds 10 to 20 kt. Seas 4 to 6 ft. .THU...NE winds 10 to 20 kt. Seas 5 to 7 ft. .THU NIGHT...N winds 10 to 20 kt. Seas 5 to 7 ft. .FRI...NE winds 10 to 20 kt. Seas 6 to 8 ft. .FRI NIGHT...NE winds 10 to 20 kt. Seas 6 to 9 ft. .SAT...NE winds 10 to 20 kt. Seas 7 to 10 ft. .SAT NIGHT...NE winds 10 to 20 kt. Seas 7 to 10 ft. Caribbean between 64W and 72W .THIS AFTERNOON...NE winds 10 to 15 kt Gulf of Venezuela, and E less than 10 kt elsewhere. Seas 3 to 4 ft. .TONIGHT...NE winds 10 to 20 kt Gulf of Venezuela, and NE less than 10 kt elsewhere. Seas 3 to 4 ft. .WED...NE winds 10 to 15 kt. Seas 3 to 4 ft. .WED NIGHT...NE winds 10 to 15 kt. Seas 3 to 5 ft. .THU...E winds 10 to 20 kt. Seas 3 to 5 ft. .THU NIGHT...E winds 10 to 20 kt. Seas 4 to 6 ft. .FRI...E winds 10 to 20 kt. Seas 5 to 7 ft. .FRI NIGHT...E winds 10 to 20 kt. Seas 5 to 7 ft. .SAT...E winds 10 to 20 kt. Seas 6 to 8 ft. .SAT NIGHT...E winds 15 to 25 kt. Seas 6 to 8 ft. Offshore Leeward Islands and adjacent ATLC waters from 15N to 19N W of 55W .THIS AFTERNOON...S winds less than 10 kt. Seas 4 to 6 ft. .TONIGHT...S winds less than 10 kt. Seas 4 to 6 ft. .WED...S winds 10 to 15 kt. Seas 4 to 6 ft. .WED NIGHT...S winds less than 10 kt. Seas 4 to 6 ft. .THU...SE winds less than 10 kt. Seas 5 to 7 ft. .THU NIGHT...E winds less than 10 kt. Seas 6 to 8 ft. .FRI...SE winds 10 to 15 kt. Seas 6 to 8 ft. .FRI NIGHT...E winds 10 to 15 kt. Seas 5 to 7 ft. .SAT...E winds 10 to 15 kt. Seas 5 to 7 ft. .SAT NIGHT...E winds 10 to 20 kt. Seas 5 to 7 ft. Offshore Windward Islands and adjacent ATLC waters from 07N to 15N W of 55W .THIS AFTERNOON...SE winds less than 10 kt. Seas 4 to 6 ft. .TONIGHT...E winds 10 to 15 kt. Seas 4 to 6 ft. .WED...E winds 10 to 15 kt. Seas 4 to 6 ft. .WED NIGHT...E winds 10 to 15 kt. Seas 4 to 6 ft. .THU...E winds 10 to 15 kt. Seas 4 to 6 ft. .THU NIGHT...E winds 10 to 15 kt. Seas 4 to 6 ft. .FRI...E winds 10 to 15 kt. Seas 5 to 7 ft. .FRI NIGHT...E winds 10 to 20 kt. Seas 6 to 8 ft. .SAT...E winds 10 to 20 kt. Seas 6 to 8 ft. .SAT NIGHT...E winds 10 to 20 kt. Seas 6 to 8 ft. Synopsis for the the SW N Atlantic including the Bahamas .SYNOPSIS...Fresh to strong winds and rough seas in the E semicircle of a non-tropical low of 1008 mb near 25N58W will continue affect the offshore waters N of 21N and E of 62W through this evening as the low open opens into a trough and moves N of the area. Strong to near gale-force winds will precede and continue to follow a cold front that extends from 31N67W to the Turks and Caicos into the Windward Passage. The front will reach from near Bermuda to N Hispaniola this afternoon, and from 31N60W to Puerto Rico Wed morning. A low pressure system is forecast to develop along this front tonight into Wed, which will support the development of gale-force winds and very rough seas between Bermuda and the Bahamas tonight through Wed afternoon. Afterward, winds and seas will gradually diminish across the region through Thu night. Looking ahead, fresh to strong southerly winds will develop over the NE Florida offshore waters on Thu ahead of a strong cold front forecast to enter the NW offshore waters late Thu into Thu evening. Near gale-force NW winds will follow this front, which is forecast to reach from Bermuda to the central Bahamas late Fri. The front will move E of the area on Sat. ATLC waters from 27N to 31N W of 77W .THIS AFTERNOON...N winds 10 to 20 kt. Seas 7 to 10 ft. .TONIGHT...N winds 10 to 20 kt. Seas 7 to 10 ft. .WED...N winds 10 to 15 kt, diminishing to less than 10 kt in the afternoon. Seas 6 to 8 ft. .WED NIGHT...W winds less than 10 kt. Seas 6 to 9 ft. .THU...SW winds 10 to 20 kt. Seas 6 to 8 ft. .THU NIGHT...W winds 20 to 30 kt. Seas 7 to 10 ft. .FRI...NW winds 20 to 25 kt, shifting to N 10 to 20 kt in the afternoon. Seas 8 to 12 ft. .FRI NIGHT...NE winds 10 to 15 kt, shifting to SE after midnight. Seas 6 to 9 ft. .SAT...S winds 10 to 15 kt. Seas 4 to 6 ft. .SAT NIGHT...SW winds 10 to 15 kt, diminishing to less than 10 kt after midnight. Seas 3 to 5 ft. ATLC waters from 27N to 31N between 65W and 77W ...GALE WARNING... .THIS AFTERNOON...NW winds 20 to 25 kt W of 70W, and W 10 to 20 kt elsewhere. Seas 9 to 14 ft W of 70W, and 8 to 9 ft elsewhere. .TONIGHT...NW winds 20 to 35 kt. W of 70W, seas 12 to 17 ft. Elsewhere, seas 9 to 13 ft, building to 11 to 16 ft after midnight. .WED...NW winds 25 to 35 kt W of 70W, and NW 20 to 30 kt elsewhere. Seas 14 to 19 ft. .WED NIGHT...N winds 20 to 30 kt W of 70W, and NW 15 to 25 kt elsewhere. Seas 12 to 17 ft. .THU...NW winds 10 to 20 kt. Seas 8 to 13 ft. .THU NIGHT...W winds 10 to 20 kt. Seas 7 to 10 ft. .FRI...W winds 15 to 25 kt. Seas 8 to 13 ft. .FRI NIGHT...N winds 15 to 25 kt. Seas 8 to 13 ft. .SAT...NE winds 10 to 15 kt, shifting to S in the afternoon. Seas 7 to 10 ft. .SAT NIGHT...SW winds 10 to 15 kt. Seas 6 to 9 ft. Bahamas N of 22N .THIS AFTERNOON...N winds 10 to 20 kt. Seas 4 to 6 ft. .TONIGHT...N winds 10 to 20 kt. Seas 4 to 6 ft. .WED...N winds 10 to 15 kt, diminishing to less than 10 kt in the afternoon. Seas 4 to 6 ft. .WED NIGHT...N winds less than 10 kt, increasing to 10 to 15 kt after midnight. Seas 5 to 7 ft. .THU...N winds less than 10 kt in the morning, becoming variable winds less than 10 kt. Seas 5 to 7 ft. .THU NIGHT...W winds less than 10 kt, shifting to NW after midnight. Seas 3 to 5 ft. .FRI...N winds 10 to 20 kt. Seas 3 to 5 ft. .FRI NIGHT...NE winds 10 to 15 kt. Seas 3 to 5 ft. .SAT...SE winds less than 10 kt. Seas 3 to 5 ft. .SAT NIGHT...E winds less than 10 kt. Seas 3 to 4 ft. ATLC waters from 22N to 27N between 65W and the Bahamas .THIS AFTERNOON...NW winds 15 to 25 kt W of 70W, and W 10 to 20 kt elsewhere. Seas 7 to 10 ft. .TONIGHT...NW winds 15 to 25 kt. Seas 9 to 14 ft. .WED...NW winds 15 to 25 kt W of 70W, and W 20 to 30 kt elsewhere. Seas 12 to 17 ft. .WED NIGHT...NW winds 15 to 25 kt W of 70W, and NW 20 to 30 kt elsewhere. Seas 13 to 18 ft. .THU...NW winds 10 to 20 kt. Seas 10 to 15 ft. .THU NIGHT...NW winds 10 to 15 kt. Seas 7 to 10 ft. .FRI...W winds 10 to 15 kt. Seas 6 to 8 ft. .FRI NIGHT...N winds 10 to 15 kt. Seas 6 to 9 ft. .SAT...NE winds 10 to 15 kt, shifting to E in the afternoon. Seas 6 to 8 ft. .SAT NIGHT...SE winds less than 10 kt. Seas 6 to 8 ft. ATLC waters S of 22N W of 65W .THIS AFTERNOON...W winds less than 10 kt, increasing to 10 to 15 kt in the afternoon. Seas 4 to 6 ft. .TONIGHT...NW winds 10 to 20 kt. Seas 6 to 8 ft. .WED...NW winds 10 to 20 kt. Seas 6 to 8 ft. .WED NIGHT...NW winds 10 to 20 kt. Seas 6 to 9 ft. .THU...NW winds 10 to 15 kt, diminishing to less than 10 kt in the afternoon. Seas 7 to 10 ft. .THU NIGHT...NW winds less than 10 kt. Seas 6 to 9 ft. .FRI...Variable winds less than 10 kt, becoming NW less than 10 kt in the afternoon. Seas 4 to 6 ft. .FRI NIGHT...NE winds less than 10 kt. Seas 3 to 5 ft. .SAT...E winds 10 to 15 kt. Seas 3 to 5 ft. .SAT NIGHT...E winds 10 to 15 kt. Seas 4 to 6 ft. ATLC waters from 19N to 22N between 55W and 65W .THIS AFTERNOON...SW winds 10 to 15 kt. Seas 7 to 9 ft. .TONIGHT...SW winds 10 to 15 kt. Seas 6 to 8 ft. .WED...SW winds 10 to 15 kt. Seas 6 to 8 ft. .WED NIGHT...SW winds 10 to 15 kt. Seas 6 to 9 ft. .THU...SW winds 10 to 15 kt. Seas 8 to 11 ft. .THU NIGHT...W winds 10 to 15 kt, diminishing to less than 10 kt after midnight. Seas 8 to 11 ft. .FRI...S winds less than 10 kt. Seas 7 to 10 ft. .FRI NIGHT...S winds less than 10 kt, shifting to NE after midnight. Seas 6 to 8 ft. .SAT...E winds less than 10 kt. Seas 4 to 6 ft. .SAT NIGHT...E winds 10 to 15 kt. Seas 4 to 6 ft.