000 AXNT20 KNHC 041521 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Wed Oct 4 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... Tropical Storm Philippe is centered near 21.2N 65.7W at 04/1500 UTC or 170 nm NNW of St. Thomas, moving NNW at 6 kt. Estimated minimum central pressure is 1004 mb. Maximum sustained wind speed is 40 kt with gusts to 50 kt. The center is partially exposed about 60 nm to the north of numerous strong to scattered moderate showers and thunderstorms. Associated heavy rainfall is expected to produce flash flooding across portions of the United States and British Virgin Islands through today. Scattered showers and thunderstorm are also evident within 75 to 90 nm to the northeast of the center. Seas in excess of 12 ft are noted with 180 nm to the north of the center and within 60 nm to the south of center, with peak seas to 18 ft. Philippe is expected to pick up speed moving northward tonight, maintaining tropical storm strength. Tropical storm conditions are possible on Bermuda beginning Friday morning, and a Tropical Storm Watch is now in effect for the island. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at the website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml, and the latest Philippe NHC Forecast/Advisory and Public Advisory, at www.hurricanes.gov, for more details. ...TROPICAL WAVES... An eastern Atlantic tropical wave has its axis along 31W from 03N to 15N. It is moving westward at 10 to 20 kt. No significant convection is noted near the wave axis at this time. A central Atlantic tropical wave has its axis along 56W south of 17N, moving westward at about 15 kt. Scattered moderate convection is active from 12N to 14N between 51W and 53W. ...MONSOON TROUGH/ITCZ... The monsoon trough axis extends from the coast of Mauritania near 19N16W to 10N30W. The ITCZ extends from 10N32W to 08N40W to 09N54W, and from 08N56W to 09N61W. Scattered moderate convection is noted from 11N to 13N between 25W and 28W, and from 06N to 08N between 35W and 45W. ...GULF OF MEXICO... A ridge extends from high pressure centered over the Carolinas to the north-central Gulf. A weak trough breaks up the ridge slightly over the coast of Texas. The pattern is supporting moderate to fresh E to SE winds across all but the far southwest Gulf, where light to gentle breezes are noted. Winds converging into the trough over Texas along with diffluent flow aloft are supporting scattered showers and thunderstorms in a line extending south of Freeport, Texas to around 25N95W. Wave heights are 4 to 6 ft across the basin, except 1 to 3 ft over the far southwest Gulf. For the forecast, high pressure will dominate the Gulf waters supporting moderate to fresh easterly winds over just about the entire basin. As the gradient slackens through Thu, this will allow for these winds to diminish to gentle to moderate speeds. Light to gentle winds are forecast elsewhere through Fri night. A cold front is forecast to reach the northern Gulf Fri into Sat followed by fresh to strong winds and moderate seas. ...CARIBBEAN SEA... Please refer to the Special Features section for details on Tropical Storm Philippe. A broad mid to upper level trough reaches from off the Carolina coast southward through central Cuba to off the coast of Nicaragua. Divergent flow aloft is supporting scattered showers and thunderstorms off the coast of southeast Cuba, south of Jamaica, and across Haiti and the Windward Passage. Fresh SE winds and 3 to 5 ft seas are noted over the eastern Caribbean east of 65W. Convergence related to these winds along with divergent flow aloft is supporting a cluster of moderate to strong thunderstorms about 60 nm to the northeast of Bonaire in the south- central Caribbean. Moderate NE winds and 3 to 5 ft seas are noted north of 20N, with mostly gentle breezes and 1 to 3 ft seas elsewhere west of 65W. Scattered showers and thunderstorms are active north the monsoon trough over Providencia Island in the southwest Caribbean, and off eastern Panama to the south of the monsoon trough. For the forecast, rough seas across the area east of the Leeward Islands generated by Philippe will continue to subside today. Light to gentle trade winds will be over the basin through the next few days, except for moderate to fresh southerly winds in the eastern Caribbean today. ...ATLANTIC OCEAN... Please refer to the Special Features section for details on Tropical Storm Philippe. A trough reaches from 31N52W to near 26N61W is starting to lose definition as Philippe moves northward from north of the Leeward and Virgin Islands. Moderate winds are noted outside of the immediate area of Philippe west of 55W, except for moderate to fresh NE winds off northeast Florida, with 6 to 8 ft seas. Farther east, a ridge extends from near the Azores Islands to 25N50W. Fresh SE winds and 5 to 7 ft seas are noted between the ridge and the aforementioned surface trough, north of 28N between 35W and 55W. Moderate to fresh easterly trade winds are evident south of ridge with 5 to 7 ft seas. Gentle breezes are noted along the ridge axis. Over the eastern Atlantic, a trough is noted east of the ridge and just west of the Canary Islands from 25N to 30N between 20W and 25W. Fresh to strong NE to E wind are noted across the Canary Islands east of the trough, with 6 to 8 ft seas. Gentle to moderate winds are noted elsewhere east of 35W, with 5 to 7 ft seas in mixed swell. For the forecast, Philippe will continue northward over the next two to three days, and is forecast to be well north of the area by late Sat as it transitions to an extratropical system. The pressure gradient over the western Atlantic will support fresh northeast winds north of the Bahamas through tonight, then diminish afterward. $$ Christensen