000 AXNT20 KNHC 150538 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0615 UTC Sun Dec 15 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 0000 UTC surface analysis and satellite imagery through 0500 UTC. ...SPECIAL FEATURES... Western Atlantic Gale Warning: The pressure gradient between a 1051 mb high pressure over southeastern Canada and 1009 mb low pressure and a sharp trough over and north of Hispaniola continues to support NE near-gale to gale-force winds north of 27N between 68W and 75W. Seas in this general area are peaking at 17 to 19 ft. These conditions are forecast to continue through early Sunday morning. As the low and related trough weaken Sunday afternoon through Sunday night, winds and seas will gradually subside as the pressure gradient decreases. Eastern Atlantic Gale Warning: A broad 1001 mb oceanic low pressure near 30N30W is generating northerly near-gale to gale- force winds north of 28N between 32W and 37W. Seas under these winds are peaking at 18 to 21 ft. This low pressure is forecast to move north-northeastward Sunday and Sunday night. This should allow marine conditions to gradually improve starting late Sunday afternoon. In addition, Meteo-France has also issued GALE WARNINGS for the CANARAIS, IRVING, METEOR, and MADEIRA Marine Zones due to the same oceanic low. Please refer to the Meteo- France High Seas Warning/Forecast at website: https://wwmiws.wmo.int/index.php/metareas/affiche/2 for more details. For both Gale Warnings, please read the latest High Seas and Offshore Waters Forecasts issued by the National Hurricane Center at website: https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and https://www.nhc.noaa.gov/marine/offshores.php for more information. ...MONSOON TROUGH/ITCZ... A monsoon trough stays mostly over the Africa Continent. An ITCZ extends westward from off the coast of Sierra Leone at 07N15W to 04N35W, then turns northwestward to 09N55W. Scattered moderate convection is noted near and up to 150 nm north of the ITCZ. ...GULF OF MEXICO... A broad surface ridge runs southwestward from the Florida Panhandle to a 1020 mb high near Tampico, Mexico. Fresh to strong ENE winds and seas at 6 to 8 ft are present across the Florida Straits. Fresh ENE to E winds and 4 to 6 ft seas are present for the rest of the eastern Gulf. Gentle to moderate with locally fresh NE to SE winds and seas of 3 to 6 ft prevail elsewhere in the Gulf. For the forecast, a strong ridge over the eastern United States will continue to support fresh to strong NE to E winds and moderate to rough seas over the eastern Gulf, including the Straits of Florida, through early Mon. Then, gentle to moderate winds and slight to moderate seas are expected Mon and Tue. Looking ahead, the next cold front should reach the northwestern Gulf by Wed night. ...CARIBBEAN SEA... A broad 1009 mb low and related sharp surface trough is causing scattered showers and isolated strong thunderstorms over and near Hispaniola. Fresh to strong NE winds and seas at 5 to 8 ft are evident at the northwestern basin. Moderate to fresh NNE to NE winds with 5 to 7 ft seas are seen in the rest of the western basin, including waters near the Windward Passage and Jamaica. Gentle to moderate NE to SE winds and seas of 3 to 5 ft prevail for the remainder of the Caribbean Sea. For the forecast, a strong pressure gradient will continue to produce fresh to strong NE winds over the northwestern basin and through the Windward Passage until early Sun. The broad low and associated surface trough will drift westward across the central Caribbean on Sun while weakening. This will cause the pressure gradient to relax across most of the basin, allowing for gentle to moderate trades through Tue. Looking ahead, a building ridge north of the area may enhance the trade wind flow over the central basin, reaching fresh to strong Tue night through Wed night. ...ATLANTIC OCEAN... Please refer to the SPECIAL FEATURES section at the beginning on two Gale Warnings. Outside the Gale Warning area in the western Atlantic, fresh to strong with locally near-gale ENE to E winds and seas of 12 to 17 ft are seen north of 23N between 63W and the Georgia/Florida coast. To the south from 20N to 23N, fresh to strong NE winds and 7 to 11 ft seas exist between 70W and the Great Bahama Bank, while gentle to moderate SE winds and seas at 7 to 9 ft dominate between 63W and 70W. Farther east, moderate to fresh ENE to SE winds and seas of 8 to 11 ft are found north of 20N between 55W and 63W. At the central Atlantic north of 20N between 44W and 55W, gentle to moderate NE to ESE winds and 8 to 10 ft seas in large NE swells are noted. North of 20N between 35W and 44W outside the Gale Warning area, moderate to fresh NW to N winds with 8 to 16 ft seas in large to very large northerly swell exist. For the Tropical Atlantic from 04N to 20N between 35W and the Lesser Antilles, gentle to moderate N to E to ESE winds and seas at 5 to 7 ft seas are evident. Light to gentle winds with 4 to 6 ft seas in mixed moderate swells prevail for the rest of the Atlantic Basin west of 35W. For the forecast W of 55W, gale-force winds between the Bahamas and Bermuda will prevail through Sun morning. Marine conditions will gradually improve late Sun and Mon, and by Tue and Wed winds will be reduced to between moderate and fresh across the entire area. $$ Chan