000 AXNT20 KNHC 090506 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Sat Dec 9 2023 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 0445 UTC. ...SPECIAL FEATURES... Gulf of Mexico Gale Warning: A strong cold front will enter the NW Gulf Sat evening. The front will reach from Mobile, AL to Tuxpan, Mexico Sun morning, from Cedar Key, FL to Merida, Mexico in the NW Yucatan peninsula Sun evening, and exit the basin Mon morning. Strong to gale force winds are expected behind the front across the western Gulf, from offshore southern Texas southward to the Bay of Campeche Sat night through Sun evening. Minimal storm force NW winds are expected over the SW Gulf, including the Veracruz area Sun afternoon. Seas are forecast to build to 16 to 18 ft with the strongest winds. A line of strong thunderstorms is likely to accompany the cold front as it moves across the Gulf of Mexico. Winds and seas will gradually subside across the basin late Mon. Atlantic Significant Swell Event: A cold front extends from 31N39W to 23N50W, where it becomes a stationary front to the Dominican Republic near 20N69W. Although winds associated with this front have diminished south of 31N, large NW swell, with seas of 12 to 13 ft is present north of 29N and between 45W and 58W. Seas of 8 to 12 ft are noted behind the front to 70W, and also east of the front to 35W and north of 28N. These seas will subside gradually and decay below 12 ft by Sat. Please read the latest High Seas Forecast and the Offshore Waters Forecast issued by the National Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and www.nhc.noaa.gov/marine/offshores.php for details on both special features. ...MONSOON TROUGH/ITCZ... The monsoon trough is confined to the African continent. The ITCZ extends from 079N14W to 06N30W to 03N50W. Scattered moderate to strong convection is observed from 01N to 08N between 25W and 40W. ...GULF OF MEXICO... Please see the SPECIAL FEATURES section above for more information about the Gale Warning that will begin Saturday night over the Western Gulf of Mexico. A 1026 mb high pressure centered over the western Atlantic near 30N71W spreads a ridge over the Gulf of Mexico. Moderate to fresh return flow is noted in the latest scatterometer pass in the eastern basin east of 86W and in the western basin west of 92W. Gentle southerly flow was captured in the central portions of the basin where seas are 3 ft or less. Seas elsewhere are 4 to 6 ft. For the forecast, moderate to locally fresh return flow will continue over the western Gulf tonight and Sat ahead of the next cold front forecast to enter the NW Gulf Sat evening. A line of strong thunderstorms is likely to accompany the cold front as it moves across the Gulf of Mexico. Winds and seas will gradually subside across the basin late Mon. ...CARIBBEAN SEA... High pressure north of the Greater Antilles and lower pressures over Colombia are helping to sustain strong trade winds in the south-central Caribbean Sea, which were noted in a recent scatterometer pass. Seas are 9 to 11 ft offshore NW Colombia, mainly south of 15N. The scatterometer pass also confirmed fresh to strong NE winds within the Windward Passage, elevating seas up to 7 ft. Elsewhere, fresh trade winds are noted in the eastern Caribbean, where seas are 5 to 7 ft, and moderate NE to E winds are noted in the NW basin where seas are 3 to 5 ft. Scattered showers and thunderstorms are noted in the NW Caribbean north of 18N. For the forecast, fresh ENE to E winds in the lee of Cuba will persist tonight. Strong NE winds in the Windward Passage will continue through Sat night. Strengthening high pressure N of the area will bring an increase in the aerial extent of strong trade winds across the central Caribbean Sea tonight through Sun, with the strongest winds near the coast of Colombia. Looking ahead, the next cold front will enter the northwest Caribbean late Sun night or early Mon, followed by fresh N to NE winds with seas building to 9 ft in the Yucatan Channel. ...ATLANTIC OCEAN Please see the Special Features section above for details about very rough seas in the central Atlantic, north of 27N between 35W and 63W. The main feature in the basin is the front described in the Special Features section. West of the front, a 1026 mb high pressure is centered east of Florida near 30N71W. Gentle anticyclonic winds surround the high north of 25N. Fresh E-NE winds are noted south of 25N and west of 50W. A scatterometer pass noted fresh to strong winds near the entrance and within the Windward Passage. Farther east, fresh tradewinds are noted from 10N to 25N between 17W and 40W due to the pressure gradient between high pressure noted over the Madiera Islands and lower pressures from a trough along the west coast of Africa. Seas are 6 to 8 ft in this region. For the forecast W of 55W, the front will remain nearly stationary along 20N-21N Sat. Strengthening high pressure N of the area will push the front farther south on Sun toward the northern Leeward Islands as a dissipating front. The gradient between the strong high pressure along 31N and lower pressure associated with the stalled front will continue to produce fresh to strong NE to E trade winds south of 23N through Sun. On Sun, fresh to strong southerly flow will set up over the waters east of northeast Florida to about 70W in advance of the next cold front. This cold front is expected to move into the NW forecast waters late Sun. Strong to near-gale force winds are likely on both sides of the front, with brief gales possible Sun night N of 29N between NE Florida and 73W. Seas will build ahead and behind the cold front. $$ Mora