442 AXNT20 KNHC 131216 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Sat Jan 13 2024 Tropical Weather Discussion for North America, Central America Gulf of Mexico, Caribbean Sea, northern sections of South America, and Atlantic Ocean to the African coast from the Equator to 31N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0600 UTC surface analysis and satellite imagery through 1000 UTC. ...SPECIAL FEATURES... EASTERN ATLANTIC GALE AND SIGNIFICANT SWELL EVENT: Persistent large northerly swell is going to sustain seas of 12 to 14 ft, north of 25N and east of 45W through early this evening. Two low pressure systems are expected to merge into one near 33N38W tonight. This new low will deepen rapidly while moving southeastward, causing strong to gale-force NW winds north of 28N and east of 48W late tonight. The combination of existing northerly swell and building wind waves will cause seas north of 26N and west of 48W to peak at 14 to 22 ft. Once the low begins to gradually weaken late Sun afternoon, both winds and seas should slowly subside Sun evening through Mon. Please read the latest High Seas Forecast issued by the National Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details. METEO-FRANCE MARINE ZONE GALE WARNING: METEO-FRANCE is forecasting gale winds in the marine zone of IRVING until 15Z Saturday. Please refer to the METEO-FRANCE High Seas Warning at https://wwmiws.wmo.int/index.php/metareas/display/2 for more details. ...MONSOON TROUGH/ITCZ... A monsoon trough enters the Atlantic along the coast of Sierra Leone near Freetown, then runs southwestward to 05N20W. An ITCZ then continues westward from 05N20W across 03N25W to 05N36W. Scattered moderate convection is seen south of the monsoon trough from 05N to 07N between the Sierra Leone/Liberia coast and 19W. Widely scattered moderate convection is present near and up to 250 nm north of the ITCZ. ...GULF OF MEXICO... A cold front extends southwestward from south of Cedar Key, Florida to the eastern Bay of Campeche. Scattered showers and isolated thunderstorms are occurring up to 60 nm along either side of the front. Fresh to strong N to NE winds and seas of 8 to 10 ft are seen behind this front over the northeastern and central Gulf, including the eastern Bay of Campeche. For the western Gulf, a 1018 mb high over southern Louisiana is supporting gentle to moderate NE to E winds and 4 to 7 ft seas in moderate northerly swell. Gentle to moderate southerly winds and seas at 4 to 6 ft prevail for the rest of the Gulf, including the Florida Straits. For the forecast, the cold front will push further southeastward this morning, and fresh to strong northerly winds along with rough seas will persist behind this front across the central and eastern Gulf. Afterward, it is expected to stall from the Florida Straits to the Yucatan Channel this afternoon through Sun, which will cause a period of fresh to strong NE winds just north of the Yucatan Peninsula and Channel on Sun. Winds and seas across the Gulf will finally diminish by Sun evening as the 1018 mb high builds over the northern Gulf. Looking ahead, another front may enter the northwestern Gulf by late Mon, and exit southeast of the Gulf by late Wed night. Fresh to strong northerly winds and building seas will follow this second front, with winds possibly reaching gale force over the west-central and southwestern Gulf Tue and Tue night. ...CARIBBEAN SEA... A 1020 mb high to the northeast near 25N57W continues to promote a relatively fair trade-wind regime across much of the basin. Convergent trades are triggering widely scattered showers across the eastern basin, including the Lesser Antilles and Virgin Islands. Fresh to locally strong winds are from the E at the south-central basin, while from the SE at the Gulf of Honduras. Seas at both locations are between 5 and 7 ft. Gentle to moderate E to SE to S winds along with 3 to 5 ft seas are present at the southwestern basin, and near the Cayman Islands. Light to gentle winds and 2 to 4 ft seas are noted near the Windward Passage. Moderate to locally fresh easterly trades and seas at 4 to 6 ft prevail elsewhere in the Caribbean Sea. For the forecast, trade winds will pulse to between fresh and strong at the central Caribbean this morning and Sun morning. By Sun night, fresh to strong trades along with moderate to rough seas are expected to dominate the central Caribbean as high pressure develops north of the region. Fresh with locally strong SE winds and moderate seas are expected to persist over the northwestern Caribbean this morning ahead of a cold front in the eastern Gulf of Mexico. This front is forecast to weaken and stall across the Yucatan Channel this afternoon through Sun, allowing winds and seas to subside at the northwestern Caribbean. Looking ahead, another cold front may move into the Yucatan Channel by late Wed. ...ATLANTIC OCEAN... Please read the SPECIAL FEATURES section at the beginning about Gales and Significant Swell. A cold front is along the Georgia and northeast Florida coast this morning. Scattered showers and isolated thunderstorms are flaring up near and east of this front, north of 28N between 78W and the Georgia-NE Florida coast. Another cold front curves westward from a triple point near 33N39W across 31N40W to 29N56W. Widely scattered moderate convection is noted near and up to 80 nm south of this front. Convergent southwesterly winds farther southeast of this front are triggering similar convection north of 26N between 33W and 39W. A third cold front stretches southwestward from east of Madeira across 31N16W and the Canary Islands to 15N41W. Patchy showers are seen up to 40 nm along either side of this feature. A surface trough near 03N40W is generating numerous moderate convection from the Equator to 03N between 37W and 48W. Refer to the Monsoon Trough/ITCZ section for additional convection in the Atlantic Basin. Outside the Gale and Significant Swell area mentioned in the Special Features section, fresh to locally strong NW to N winds and 8 to 11 ft seas dominate north of 23N between 45W and 53W. Farther south, gentle to moderate N to ENE winds and seas of 8 to 11 ft in large N swell exist from 10N to 23N/25N between 35W and the Lesser Antilles. For the western Atlantic, a 1020 mb high near 25N57W is supporting gentle to moderate NE to SE winds and seas at 4 to 7 ft north of 20N between 53W and 70W. To the west, moderate southerly winds and seas of 4 to 6 ft are evident from 20N to 27N between 70W and the Bahamas. To the north, fresh to strong SW to W winds and 8 to 10 ft seas prevail north of 27N between 70W and the NE Florida/Georgia coast. For the forecast, fresh to strong southerly winds and rough seas will continue across the waters north of the Bahamas, and west of 70W this morning as a cold front is about to move off the northeast Florida coast. As this front progresses eastward across these waters, it will cause winds to shift to the NW later today. The front is going to weaken and reach from near Bermuda to the Great Bahama Bank tonight. Winds and seas will diminish as high pressure builds eastward along 30N following the front. The front will then become stationary south of Bermuda and over the northwest Bahamas on Sun, bringing a period of fresh to strong NE winds there. As it lifts northward as a warm front on Mon, these winds will decrease while shifting to the SE. Looking ahead, SW winds will increase north of 27N on Tue ahead of another cold front moving off the northeast Florida coast. Fresh to strong NW winds will follow the front north of 27N as the front reaches from Bermuda to eastern Cuba Wed night. $$ Chan