000 AXNT20 KNHC 092338 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Sun Sep 10 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 1800 UTC surface analysis and satellite imagery through 2350 UTC. ...SPECIAL FEATURES... Hurricane Lee is centered near 20.7N 59.1W at 09/2100 UTC or 270 nm NE of the Northern Leeward Islands, moving WNW at 9 kt. Estimated minimum central pressure is 958 mb. Maximum sustained wind speed is 100 kt with gusts to 120 kt. Peak seas are 40 kt in the area of strongest winds. Numerous moderate to strong convection is from 18N to 24N between 55W and 63W. On the forecast track, Lee is expected to pass well to the north of the northern Leeward Islands, the Virgin Islands, and Puerto Rico into early next week. Lee is a category 3 hurricane on the Saffir- Simpson Hurricane Wind Scale. Gradual restrengthening is possible during the next couple of days. Swells generated by Lee are affecting portions of the Lesser Antilles, and are spreading westward to the British and U.S. Virgin Islands, Puerto Rico, Hispaniola, the Turks and Caicos Islands, the Bahamas, and Bermuda through this weekend. These swells are likely to cause life- threatening surf and rip current conditions. Dangerous surf and rip currents are expected to begin along most of the U.S. East Coast on Sunday and Monday and worsen through the week. Please consult products from your local weather office. Tropical Storm Margot is centered near 21.0N 38.7W at 09/2100 UTC or 890 nm WNW of the Cabo Verde Islands, moving NW at 8 kt. Estimated minimum central pressure is 1004 mb. Maximum sustained wind speed is 40 kt with gusts to 50 kt. Peak seas are 16 ft. Numerous moderate to strong convection from 20N to 23N between 34W and 39W. Scattered moderate convection is elsewhete from 18N to 27N between 32W and 39W. Margot is expected to continue to move toward the northwest during the next day or so. A NNW to N motion is forecast to begin by late Sunday. Gradual strengthening is forecast over the next several days, and Margot is forecast to become a hurricane next week. 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 NHC Forecast/Advisory and Public Advisory on Lee and Margot at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave is in the eastern Atlantic with axis just W of the Cape Verde Islands near 26W, moving westward around 10 kt. Scattered moderate convection is from 08N to 15N between 25W and 31W. This wave is expected to become entrained in the prevailing southeasterly wind flow that is guiding Margot, which will weaken it and transport it off to the NW through Sun. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic near 16N16W then reaches SW to south of the Cabo Verde Islands at 13N25W, before resuming from 10N35W to 07N43W. The ITCZ begins at 07N43W and ends at 08N53W. Numerous moderate to strong convection is across the Guinea-Bissau and Guinea offshore waters. Otherwise, scattered moderate convection is elsewhere from 04N to 10N between 32W and 45W. ...GULF OF MEXICO... A very weak stationary front curves westward from the Florida Panhandle southward to near 27N and across the Louisiana/Texas border coastal waters. Isolated thunderstorms are occurring near the front. However, isolated small clusters of showers and moderate thunderstorms are occurring across the Florida Big Bend, and offshore of south-central Texas. In addition, an outflow boundary has developed in the offshore waters of south- central Texas. A surface trough near the west coast of the Yucatan Peninsula is causing isolated showers and thunderstorms across the Bay of Campeche. Otherwise outside of convection, modest ridging related to a 1016 mb high along the E Texas coast is producing light to gentle winds with 1 to 2 ft seas across the basin. For the forecast, a weak ridge will dominate the Gulf waters throughout the forecast period supporting light to moderate winds. ...CARIBBEAN SEA... Please read the SPECIAL FEATURES section about large swell generated by Major Hurricane Lee impacting the northeast Caribbean islands. An upper-level trough extends southward from western Cuba to northwestern Colombia. Combining with modest convergent easterly trades, widely scattered showers and thunderstorms are occurring across the Gulf of Honduras, and south of 10.5N, along the monsoon trough. A weak trade-wind pattern is persisting across east and west portions of the basin this morning, with fresh to locally strong ENE to E winds and seas of 6 to 9 ft occurring in the south- central basin, including the Gulf of Venezuela. Strong ENE swell from Lee has begun to enter the passages of the NE Caribbean recently and will build throughout the day as this swell propagates westward across the eastern basin. For the forecast, Hurricane Lee will move to 21.4N 60.3W Sun morning, 22.1N 61.6W Sun afternoon, 22.9N 62.9W Mon morning, 23.3N 64.1W Mon afternoon, 23.6N 65.3W Tue morning, and 23.9N 66.3W Tue afternoon. Lee will change little in intensity as it moves near 25.1N 67.8W Wed afternoon. In the Caribbean, moderate to fresh trade winds will continue in the central and E Caribbean through the weekend. Large easterly swell over the tropical Atlantic waters and affecting the passages of the NE Caribbean, will reach the the Mona Passage Sun. ...ATLANTIC OCEAN... Please see the SPECIAL FEATURES section above for details on Major Hurricane Lee and on Tropical Storm Margot. For convection information across the tropical Atlantic, please see the TROPICAL WAVES and MONSOON TROUGH/ITCZ sections. A modest but persistent surface trough extends northeastward from the central Bahamas to west of Bermuda near 31N72W. Scattered showers and isolated thunderstorms are present near and up to 180 nm east side of this feature, including the rest of the Bahamas. An upper-level low at the central Atlantic near 29N45W is producing scattered moderate convection north of 28N between 43W and 48W North of 20N, fresh to locally strong NE to ESE peripheral winds of Hurricane Lee and Tropical Storm Margot are found northward to 27N between 51W and 64W, and between 32W and 42W respectively. Otherwise, gentle to moderate NE to SE winds and seas of 5 to 8 ft in mixed swell dominates north of 24N between 25W and the Georgia-Florida coast. From 05N to 24N outside the direct influence of Lee and Margot, gentle to moderate with locally fresh NE to SE winds and 6 to 10 ft seas in mixed swells exist between 30W and the Lesser Antilles. Near the Canary Islands, gentle to moderate with locally fresh NNE to NE trades and seas at 5 to 8 ft are found north of 18N between the Africa coast and 25W. Near the Cabo Verde Islands, gentle monsoonal winds and 3 to 5 ft seas are seen south of 18N between the central Africa coast and 23W. Gentle to moderate with locally fresh southerly winds and 6 to 10 ft seas in moderate to large southerly swell prevail for the remainder of the Atlantic Basin. For the forecast W of 55W, Hurricane Lee will move to 21.4N 60.3W Sun morning, 22.1N 61.6W Sun afternoon, 22.9N 62.9W Mon morning, 23.3N 64.1W Mon afternoon, 23.6N 65.3W Tue morning, and 23.9N 66.3W Tue afternoon. Lee will change little in intensity as it moves near 25.1N 67.8W Wed afternoon. In the Caribbean, moderate to fresh trade winds will continue in the central and E Caribbean through the weekend. Large easterly swell will reach the Mona Passage on Sun, the Turks and Caicos Islands Sun evening and the southeastern Bahamas Mon. $$ Ramos