000 AXNT20 KNHC 191058 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Thu Oct 19 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 0600 UTC surface analysis and satellite imagery through 1050 UTC. ...SPECIAL FEATURES... Tropical Storm Tammy is centered near 13.5N 54.8W at 19/0900 UTC or 420 nm ESE of Guadeloupe, moving W at 15 kt. Estimated minimum central pressure is 1006 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Peak seas are currently around 18 ft. Numerous moderate isolated strong convection is noted from 06N to 15N and between 50W and 56W. On the forecast track, the center of Tammy will move near or over the Leeward Islands Friday and Saturday. Gradual strengthening is forecast during the next few days and Tammy could be near hurricane intensity by the end of the weekend. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest Tammy NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the tropical Atlantic through the coast of Guinea-Bissau near 11N16W and continues southwestward to 07N27W and then to 01N41W. Numerous moderate to isolated strong convection is observed from 04N to 13N between 18W and 35W. ...GULF OF MEXICO... The Gulf of Mexico remains under the influence of a surface ridge anchored by a 1023 mb high pressure center over the Carolinas, which is providing E to SE gentle to moderate winds and slight seas basin-wide. For the forecast, high pressure will continue to dominate the Gulf waters providing gentle to moderate anticyclonic winds through tonight. A frontal system will bring fresh winds to the NE Gulf Fri and Fri night. Light to gentle variable winds will dominate the basin afterward through Sun. Moderate to fresh E to SE winds are forecast to develop Sun night into early next week as the pressure gradient increases between a ridge over the E CONUS and a system of low pressure over the W CONUS. ...CARIBBEAN SEA... Please see the Special Features section above for more details on Tropical Storm Tammy located east of the Lesser Antilles. Tropical Storm Tammy is near 13.5N 54.8W at 5 AM EDT, and is moving west at 15 kt. Maximum sustained winds are 35 kt with gusts to 45 kt, and the minimum central pressure is 1006 mb. The pressure gradient between the Atlantic subtropical ridge and lower pressure in NW Colombia supports fresh to strong easterly trade winds in the south-central Caribbean and wave heights of 4-7 ft. Elsewhere, moderate or weaker winds and slight to moderate seas prevail. For the forecast, Tammy will move to 13.9N 56.4W this afternoon, 14.5N 58.2W Fri morning, 15.5N 60.0W Fri afternoon, 16.8N 61.3W Sat morning, 18.4N 62.4W Sat afternoon, and 19.9N 63.1W Sun morning. Tammy will strengthen to a hurricane near 23.3N 63.0W early Mon. A weakening stationary front extending from eastern Cuba to the Gulf of Honduras will dissipate later today. Fresh to locally strong trade winds over the central and portions of the SW basin will diminish tonight. Fresh to locally strong winds associated with Tammy will start affecting the NE Caribbean waters this evening. ...ATLANTIC OCEAN... Please see the Special Features section above for more details on Tropical Storm Tammy located east of the Lesser Antilles. Tropical Storm Tammy is near 13.5N 54.8W at 5 AM EDT, and is moving west at 15 kt. Maximum sustained winds are 35 kt with gusts to 45 kt, and the minimum central pressure is 1006 mb. A stationary front extends from 31N63W to eastern Cuba supporting scattered showers in the southern Bahamas as well as Turks and Caicos. Ahead of the front and well to the NE of Puerto Rico, upper level diffluence supports a broad area of showers and tstms from 19N to 27N between 57W and 65W. The remainder subtropical Atlc is under the influence of a ridge supporting mainly gentle to moderate winds and moderate seas. For the forecast W of 55W, Tammy will move to 13.9N 56.4W this afternoon, 14.5N 58.2W Fri morning, 15.5N 60.0W Fri afternoon, 16.8N 61.3W Sat morning, 18.4N 62.4W Sat afternoon, and 19.9N 63.1W Sun morning. Tammy will strengthen to a hurricane near 23.3N 63.0W early Mon. The stationary front will weaken today before dissipating. High pressure will build over the area in the wake of the front. The next frontal system will move offshore the southeastern United States Fri night. Fresh to strong winds and rough seas are forecast north of 27N Fri night through Sat night with this system. $$ Ramos