000 AXNT20 KNHC 131804 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Wed Dec 13 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURES... Central Atlantic Gale Warning: A newly developed 1014 mb low is centered along a stationary front near 24N43W. Near-gale to gale-force NE to ENE winds along with 14 to 16 ft seas are occurring northeast of the low from 26N to 29N between 38W and 43W. As this low gradually tracks west- northwestward through Thursday, these gale winds and even higher seas at 16 to 19 ft will shift westward. 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. Atlantic Significant North Swell: Large north swell continues to sustain 12 to 15 ft seas from the Virgin and northern Leeward Islands northeastward to near 45W between 18N and 30N. As this swell starts to decay this evening, both sea heights and coverage area will gradually decrease overnight. Seas are expected drop below 12 ft by late Thursday morning. Western Atlantic and Florida Offshore Gale Warning: A stationary front extends southwestward from near Bermuda across 31N68W and the central Bahamas and Florida Straits to beyond western Cuba. A strong high pressure is forecast to move offshore from the Carolinas early Thursday morning. Tight pressure gradient between these two features will cause fresh to strong NE winds currently across the offshore waters of southeast Florida and north of the Bahamas to become near-gale to gale-force by mid Thursday morning. Seas of 8 to 10 ft in these waters will also build further to between 11 and 15 ft by Thursday afternoon. Once the high has moved farther eastward toward the north-central Atlantic on Saturday, both winds and seas at these waters should gradually subside. Meanwhile, a low pressure system is anticipated to form near the stationary front at the southeastern Gulf of Mexico on Saturday, then moves northeastward across central and northern Florida into the western Atlantic through Sunday. This system might cause southerly gales and very rough seas in the central and northeast Florida offshore waters on Sunday, and western Atlantic waters Sunday night through Monday. For the Significant North Swell and Western Atlantic/Florida Offshore Gales, please read the latest High Seas and Offshore Waters Forecasts issued by the National Hurricane Center, at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and https://www.nhc.noaa.gov/marine/offshore.php for more details. ...MONSOON TROUGH/ITCZ... A monsoon trough stays mostly east of 10W along the central Africa coast. An ITCZ meanders west-northwestward from offshore of Liberia at 05N12W across 06N40W to just southeast of Trinidad and Tobago at 10N59W. Widely scattered to scattered moderate convection is seen up to 200 nm south, and 150 nm north of the ITCZ. ...GULF OF MEXICO... The stationary front mentioned in the Special Features section continues southwestward from the Florida Straits across western Cuba to just south of the Yucatan Channel. Convergent ENE winds to its north are causing widely scattered showers and isolated thunderstorms across the south-central and southeastern Gulf, and the Florida Straits and Yucatan Channel. Otherwise, a broad surface ridge extends southwestward from a strong 1037 mb high over northern Alabama to near Veracruz, Mexico. Fresh to strong ENE winds and seas of 6 to 9 ft are present across the eastern Gulf. Moderate to fresh ENE to ESE winds and 5 to 8 ft seas exist at the central and northwestern Gulf. Gentle to moderate NE to E winds and seas at 3 to 6 ft prevail for the rest of the Gulf. For the forecast, strong high pressure building across the eastern United States will continue to support fresh to strong winds over the eastern Gulf. Areal coverage of the fresh to strong winds will increase to the northwestern Gulf by early Thursday. A large area of near gale-force winds will develop over the north-central and eastern Gulf Thu through Fri night with the potential to reach gale force. Low pressure will develop north of the Yucatan Peninsula Fri night into Sat and then track northeastward across central Florida Sat night into Sun morning. A cold front will move into the western Gulf Sat, with strong to near-gale force winds and rough seas. The front will merge with the area of low pressure by Sat night and exit the Gulf Sun morning. ...CARIBBEAN SEA... A surface trough curves northeastward from a 1014 mb low at the western Gulf of Honduras to the southwestern end of a stationary front just south of the Yucatan Channel. Another surface trough is seen at the southwestern basin near the San Andres and Providencia Islands. Widely scattered moderate convection is occurring near these features over the northwestern basin and along the coast of Nicaragua and Costa Rica. Up to 8 inches of rain was reported at Havana, Cuba which caused some river flooding. Strong to near- gale ENE trade winds and seas of 11 to 13 ft are evident at the southwestern basin north of eastern Panama and northwestern Colombia. Fresh to strong ENE trades and 8 to 10 ft seas are found at the central and northeastern basin, and near the Windward Passage. Gentle to moderate NE to E winds and seas at 5 to 7 ft are noted at the Gulf of Honduras and waters near Costa Rica and western Panama. Moderate to fresh NE to ENE winds and 6 to 8 ft seas prevail elsewhere in the basin. For the forecast, strong high pressure north of the region will support fresh to strong trade winds across the central and eastern basin through tonight. Fresh to strong NE winds and rough seas over the northwestern basin will diminish to between moderate and fresh by this evening. Fresh to strong NE winds in the Windward Passage will diminish Fri night. ...ATLANTIC OCEAN... Please read the Special Features section at the beginning on Significant North Swell and multiple Gale Warnings. A stationary front extends southwestward from near Bermuda across 31N68W and the central Bahamas and Florida Straits to beyond western Cuba. Scattered showers and isolated thunderstorms are seen near and up to 200 nm northwest of this boundary. Another stationary front curves southwestward from south of the Azores across 31N30W and a 1014 mb low near 24N43W to east of the northern Leeward Islands at 18N57W. Scattered moderate convection is evident north 18N between 32W and 48W. Farther south, a surface trough is triggering scattered showers from 12N to 18N between 43W and 50W. Refer to the Monsoon Trough/ITCZ section for additional convection in the Atlantic Basin. Fresh to strong NE to ENE winds and seas of 7 to 10 ft are noted behind the first stationary front, including the northwest Bahamas and Florida offshore waters. Outside the winds and seas mentioned in the Special Features section, fresh to strong NE to E winds and 8 to 11 ft seas are exist from 16N to 30N between the second stationary front and the southeast Bahamas/Puerto Rico. Gentle to moderate E to SE winds and seas at 6 to 8 ft dominate the area in between these two areas, including the central Bahamas. To the south, gentle to moderate NE to SE winds and 6 to 8 ft seas are present from 04N to 16N/20N between 30W and the Lesser Antilles. Near the Canary and Cabo Verde Islands, gentle with locally moderate with locally fresh NE to SE winds and seas of 4 to 7 ft in moderate NW swell are found north of 07N between the Africa coast and 30W/second stationary front. Light to gentle winds and 4 to 6 ft seas in mixed moderate swells prevail for the remainder of the Atlantic Basin. For the forecast W of 55W, the first stationary front is forecast to lift northward towards the northwest Bahamas and the Straits of Florida today. Strong high pressure building north of the area will lead to the development of strong to near-gale force NE to E winds and building seas over the northern Bahamas and Straits of Florida today, with these winds spreading northward and eastward through Fri. Gale-force winds are expected east of Florida by the end of the week. An area of low pressure is forecast to move from the Gulf of Mexico, across Florida, and into the Atlantic waters this weekend. A large area of gale force winds are possible east of the low. $$ Chan