000 FZNT31 KNHC 240317 OFFN20 Marine Weather HF Voice Broadcast NWS National Hurricane Center Miami, FL 1117 PM EDT Thu Sep 23 2021 Marine Weather HF Voice Broadcast for the Tropical N Atlantic from 07N to 22N between 55W and 64W, the SW N Atlantic S of 31N W of 65W including 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 between 55W and 64W .SYNOPSIS...Tropical Storm Sam near 11.2N 40.9W 997 mb at 11 PM EDT moving W at 13 kt. Maximum sustained winds 60 kt gusts 75 kt. Sam will strengthen to a hurricane near 11.4N 42.9W Fri morning, move to 11.8N 45.0W Fri evening, 12.1N 46.6W Sat morning, 12.5N 47.8W Sat evening, 13.0N 49.1W Sun morning, and 13.5N 50.4W Sun evening. Sam will change little in intensity as it moves to 15.3N 53.2W by late Mon. Meanwhile, moderate trade winds will persist over much of the Caribbean into early next week, becoming fresh over the south-central Caribbean starting Fri night as high pressure builds east of the Bahamas. Fresh to strong winds are forecast in the Gulf of Honduras Sun night. NW Caribbean W of 85W .OVERNIGHT...E winds less than 10 kt. Seas 2 ft or less. .FRI...Variable winds less than 10 kt, becoming E less than 10 kt in the afternoon. Seas 2 ft or less. .FRI NIGHT...E winds 10 kt. Seas 2 ft or less. .SAT...E winds less than 10 kt. Seas 2 ft or less. .SAT NIGHT...E winds 10 to 15 kt. Seas 2 ft or less. .SUN...E winds 10 to 15 kt. Seas 2 ft or less. .SUN NIGHT...E winds 10 to 20 kt. Seas 2 ft or less. .MON...E winds 10 to 20 kt, diminishing to less than 10 kt in the afternoon. Seas 2 ft or less. .MON NIGHT...E winds 10 to 15 kt. Seas 2 ft or less. .TUE...E winds 10 to 15 kt, diminishing to less than 10 kt in the afternoon. Seas 2 ft or less. Caribbean N of 15N between 72W and 85W .OVERNIGHT...S of 18N, E winds less than 10 kt, increasing to 10 to 15 kt after midnight. Elsewhere, E winds less than 10 kt. Seas 2 ft or less. .FRI...E winds 10 to 15 kt S of 18N, and SE less than 10 kt elsewhere. Seas 2 ft or less. .FRI NIGHT...E winds 10 to 20 kt S of 18N, and E less than 10 kt elsewhere. Seas 2 ft or less. .SAT...E winds 10 to 20 kt S of 18N, and E less than 10 kt elsewhere. S of 18N, seas 2 ft or less, building to 5 ft in the afternoon. Elsewhere, seas 2 ft or less. .SAT NIGHT...E winds 10 to 20 kt S of 18N, and E less than 10 kt elsewhere. Seas 5 ft S of 18N, and 2 ft or less elsewhere. .SUN...E winds 10 to 20 kt S of 18N, and NE less than 10 kt elsewhere. Seas 5 ft S of 18N, and 2 ft or less elsewhere. .SUN NIGHT...NE winds 10 to 20 kt. Seas 5 ft S of 18N, and 2 ft or less elsewhere. .MON...NE winds 10 to 15 kt S of 18N, and NE less than 10 kt elsewhere. S of 18N, seas 5 ft in the morning, subsiding to 2 ft or less. Elsewhere, seas 2 ft or less. .MON NIGHT...E winds 10 to 15 kt S of 18N, and NE less than 10 kt elsewhere. Seas 2 ft or less. .TUE...E winds 10 to 15 kt S of 18N, and NE less than 10 kt elsewhere. Seas 2 ft or less. Caribbean from 11N to 15N W of 72W .OVERNIGHT...E winds 10 to 15 kt. Seas 2 ft or less. .FRI...E winds 10 to 15 kt. Seas 2 ft or less. .FRI NIGHT...E winds 10 to 20 kt. Seas 2 ft or less, building to 5 ft after midnight. .SAT...E winds 10 to 20 kt. Seas 5 to 6 ft. .SAT NIGHT...E winds 10 to 20 kt. Seas 5 to 6 ft. .SUN...E winds 15 to 25 kt. Seas 5 to 6 ft. .SUN NIGHT...NE winds 10 to 20 kt. Seas 5 to 6 ft. .MON...E winds 10 to 20 kt. Seas 5 to 6 ft. .MON NIGHT...NE winds 10 to 20 kt. Seas 5 ft. .TUE...E winds 10 to 20 kt. Seas 5 ft. SW Caribbean S of 11N .OVERNIGHT...NW winds less than 10 kt. Seas 2 ft or less. .FRI...SE winds less than 10 kt. Seas 2 ft or less. .FRI NIGHT...NE winds less than 10 kt. Seas 2 ft or less. .SAT...NE winds less than 10 kt. Seas 2 ft or less. .SAT NIGHT...NE winds 10 to 20 kt. Seas 2 ft or less, building to 5 ft after midnight. .SUN...NE winds 10 to 20 kt. Seas 5 ft. .SUN NIGHT...N winds 10 to 15 kt. Seas 5 to 6 ft. .MON...NE winds 10 to 20 kt. Seas 5 ft. .MON NIGHT...N winds 10 to 15 kt. Seas 5 ft. .TUE...E winds 10 to 15 kt. Seas 2 ft or less. Caribbean between 64W and 72W .OVERNIGHT...E winds 10 to 15 kt. Seas 2 ft or less. .FRI...SE winds 10 to 15 kt. Seas 2 ft or less. .FRI NIGHT...E winds 10 to 20 kt. Seas 2 ft or less, building to 5 ft after midnight. .SAT...E winds 10 to 20 kt. Seas 5 ft. .SAT NIGHT...E winds 10 to 20 kt. Gulf of Venezuela, seas 2 ft or less, building to 5 ft after midnight. Elsewhere, seas 5 ft. .SUN...E winds 10 to 20 kt. Seas 5 ft in the morning, subsiding to 2 ft or less. .SUN NIGHT...E winds 10 to 20 kt. Seas 2 ft or less. .MON...E winds 10 to 20 kt. Seas 2 ft or less. .MON NIGHT...E winds 10 to 20 kt. Seas 2 ft or less. .TUE...E winds 10 to 15 kt. Seas 2 ft or less. Offshore Leeward Islands and adjacent ATLC waters from 15N to 19N W of 55W .OVERNIGHT...SE winds 10 to 15 kt. Seas 5 to 6 ft. .FRI...SE winds 10 to 15 kt. Seas 5 to 6 ft. .FRI NIGHT...E winds 10 to 15 kt. Seas 5 to 6 ft. .SAT...E winds 10 kt. Seas 5 to 6 ft. .SAT NIGHT...E winds 10 kt. Seas 5 ft. .SUN...E winds 10 kt. Seas 5 to 6 ft. .SUN NIGHT...E winds 10 to 15 kt. Seas 5 to 7 ft. .MON...HURRICANE CONDITIONS POSSIBLE. E winds 10 to 15 kt. Seas 5 to 7 ft. .MON NIGHT...HURRICANE CONDITIONS POSSIBLE. .TUE...HURRICANE CONDITIONS POSSIBLE. Offshore Windward Islands and adjacent ATLC waters from 07N to 15N W of 55W .OVERNIGHT...E winds 10 to 15 kt. Seas 5 ft. .FRI...SE winds 10 to 15 kt. Seas 5 to 6 ft. .FRI NIGHT...E winds 10 to 15 kt. Seas 5 to 6 ft. .SAT...E winds 10 to 15 kt, diminishing to less than 10 kt in the afternoon. Seas 5 to 6 ft. .SAT NIGHT...E winds less than 10 kt, increasing to 10 to 15 kt after midnight. Seas 5 to 6 ft. .SUN...E winds 10 to 15 kt, diminishing to less than 10 kt in the afternoon. Seas 5 to 7 ft. .SUN NIGHT...E winds less than 10 kt. Seas 5 to 7 ft. .MON...HURRICANE CONDITIONS POSSIBLE. E winds less than 10 kt. Seas 5 to 7 ft. .MON NIGHT...HURRICANE CONDITIONS POSSIBLE. .TUE...HURRICANE CONDITIONS POSSIBLE. Synopsis for the the SW N Atlantic including the Bahamas .SYNOPSIS...A cold front extending from 31N77W to 28N80W will stall overnight, then dissipate through early Sun just before a second weak front possibly moves into the region late Sun. Farther east, Tropical Storm Sam near 11.2N 40.9W 997 mb at 11 PM EDT moving W at 13 kt. Maximum sustained winds 60 kt gusts 75 kt. Sam will strengthen to a hurricane near 11.4N 42.9W Fri morning, move to 11.8N 45.0W Fri evening, 12.1N 46.6W Sat morning, 12.5N 47.8W Sat evening, 13.0N 49.1W Sun morning, and 13.5N 50.4W Sun evening. Sam will change little in intensity as it moves to 15.3N 53.2W by late Mon. ATLC waters from 27N to 31N W of 77W .OVERNIGHT...E winds less than 10 kt. Seas 5 ft. .FRI...NW winds less than 10 kt, shifting to N in the afternoon. Seas 5 ft. .FRI NIGHT...NE winds 10 to 15 kt, shifting to E after midnight. Seas 5 ft. .SAT...N winds 10 to 15 kt. Seas 5 ft. .SAT NIGHT...N winds 10 to 15 kt. Seas 2 ft or less. .SUN...N winds 10 to 15 kt. Seas 2 ft or less, building to 5 ft in the afternoon. .SUN NIGHT...NE winds 10 to 15 kt, diminishing to less than 10 kt after midnight. Seas 5 ft in the evening, subsiding to 2 ft or less. .MON...N winds less than 10 kt, increasing to 10 to 15 kt in the afternoon. Seas 2 ft or less. .MON NIGHT...NE winds 10 to 15 kt, diminishing to less than 10 kt after midnight. Seas 2 ft or less. .TUE...NE winds less than 10 kt, increasing to 10 to 15 kt in the afternoon. Seas 2 ft or less. ATLC waters from 27N to 31N between 65W and 77W .OVERNIGHT...SE winds less than 10 kt W of 70W, and E 10 to 15 kt elsewhere. Seas 5 to 6 ft. .FRI...E winds less than 10 kt. Seas 5 to 6 ft. .FRI NIGHT...W of 70W, S winds less than 10 kt in the evening, becoming variable winds less than 10 kt. Elsewhere, N winds less than 10 kt. Seas 5 to 6 ft. .SAT...W winds less than 10 kt. Seas 5 to 6 ft. .SAT NIGHT...W winds less than 10 kt. Seas 5 ft. .SUN...W of 70W, NW winds 10 to 15 kt, diminishing to less than 10 kt in the afternoon. Elsewhere, NW winds less than 10 kt in the morning, becoming variable winds less than 10 kt. Seas 2 ft or less. .SUN NIGHT...W of 70W, NE winds 10 to 15 kt. Elsewhere, W winds less than 10 kt in the evening, becoming variable winds less than 10 kt. Seas 2 ft or less. .MON...W of 70W, NE winds 10 to 15 kt. Elsewhere, Variable winds less than 10 kt, becoming S less than 10 kt in the afternoon. Seas 2 ft or less. .MON NIGHT...E winds 10 to 15 kt W of 70W, and S less than 10 kt elsewhere. Seas 2 ft or less. .TUE...SE winds less than 10 kt, shifting to N in the afternoon. Seas 2 ft or less. Bahamas N of 22N .OVERNIGHT...E winds less than 10 kt. Seas 2 ft or less. .FRI...SE winds less than 10 kt. Seas 2 ft or less. .FRI NIGHT...SE winds less than 10 kt. Seas 2 ft or less. .SAT...SE winds less than 10 kt. Seas 2 ft or less. .SAT NIGHT...E winds less than 10 kt. Seas 2 ft or less. .SUN...NE winds 10 to 15 kt. Seas 2 ft or less. .SUN NIGHT...NE winds 10 to 15 kt. Seas 2 ft or less. .MON...NE winds less than 10 kt, shifting to N in the afternoon. Seas 2 ft or less. .MON NIGHT...NE winds 10 to 15 kt. Seas 2 ft or less. .TUE...N winds less than 10 kt. Seas 2 ft or less. ATLC waters from 22N to 27N between 65W and the Bahamas .OVERNIGHT...NE winds 10 to 15 kt. Seas 5 to 6 ft. .FRI...W of 70W, NE winds 10 kt in the morning, becoming variable winds less than 10 kt. Elsewhere, N winds 10 to 15 kt. Seas 5 to 6 ft. .FRI NIGHT...Variable winds less than 10 kt W of 70W, and N 10 to 15 kt elsewhere. Seas 5 ft. .SAT...E winds less than 10 kt. Seas 5 ft. .SAT NIGHT...NE winds less than 10 kt. Seas 5 ft. .SUN...E winds less than 10 kt. Seas 2 ft or less. .SUN NIGHT...E winds less than 10 kt. Seas 2 ft or less. .MON...SE winds less than 10 kt. Seas 2 ft or less. .MON NIGHT...SE winds less than 10 kt. Seas 2 ft or less. .TUE...S winds less than 10 kt. Seas 2 ft or less. ATLC waters S of 22N W of 65W .OVERNIGHT...NE winds 10 to 15 kt. Seas 5 ft. .FRI...S winds 10 to 15 kt. Seas 5 ft. .FRI NIGHT...NE winds 10 to 15 kt, shifting to E after midnight. Seas 5 ft. .SAT...SE winds less than 10 kt. Seas 2 ft or less. .SAT NIGHT...E winds less than 10 kt. Seas 2 ft or less. .SUN...E winds less than 10 kt. Seas 2 ft or less. .SUN NIGHT...E winds less than 10 kt. Seas 2 ft or less. .MON...E winds less than 10 kt. Seas 2 ft or less. .MON NIGHT...E winds less than 10 kt, increasing to 10 to 15 kt after midnight. Seas 2 ft or less. .TUE...SE winds 10 to 15 kt, shifting to E in the afternoon. Seas 2 ft or less. ATLC waters from 19N to 22N between 55W and 65W .OVERNIGHT...SE winds 10 to 15 kt. Seas 5 to 6 ft. .FRI...S winds 10 to 15 kt. Seas 5 to 6 ft. .FRI NIGHT...SE winds 10 to 15 kt. Seas 5 to 6 ft. .SAT...SE winds 10 kt. Seas 5 to 6 ft. .SAT NIGHT...E winds less than 10 kt. Seas 5 ft. .SUN...E winds less than 10 kt. Seas 5 to 6 ft. .SUN NIGHT...E winds 10 to 15 kt. Seas 5 to 6 ft. .MON...E winds 10 to 15 kt. Seas 5 to 7 ft. .MON NIGHT...TROPICAL STORM CONDITIONS POSSIBLE. E winds 10 to 15 kt. Seas 6 to 8 ft. .TUE...HURRICANE CONDITIONS POSSIBLE.