000 AXNT20 KNHC 101110 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 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 0600 UTC surface analysis and satellite imagery through 1000 UTC. ...SPECIAL FEATURES... Hurricane Lee is near 21.4N 60.5W at 5 AM EDT, or about 280 miles NE of the northern Leeward Islands, moving west-northwest at 8 kt. Maximum sustained winds are 90 kt with gusts to 110 kt. Minimum central pressure is 958 mb. Maximum sustained winds are 90 kt with gusts to 110 kt. Peak seas are estimated around 35 ft near the center. Numerous moderate to scattered strong convection is seen near within 75 nm N and 120 nm across the S semicircle. Scattered moderate to strong convection is present elsewhere up to 240 nm E and 120 nm W of the center. Lee is expected to maintain a slow W-NW to NW motion through Tue night, and slowly strengthen, while passing well north of the northern Leeward Islands, Virgin Islands and Puerto Rico. Large E to SE swell generated by Lee is propagating westward across the Atlantic, and has begun to reach the waters of Hispaniola and the Turks and Caicos Islands in recent hours. These large swells will spread west and northwestward and reach the Bahamas and 76W by late afternoon, the NW Bahamas and 78W by Mon morning, and then into the coasts of Florida and the southeastern U.S. Tue morning. These swells are likely to cause large and dangerous surf and life-threatening rip current conditions. These dangerous surf and rip currents are expected to worsen along much of the Atlantic coast of the U.S. throughout the week. Please consult products from your local weather office. Tropical Storm Margot is near 22.1N 39.6W at 5 AM EDT, or about 1100 miles W-NW of the Cabo Verde Islands, moving northwest at 7 kt. Maximum sustained winds are 45 kt with gusts to 55 kt. Minimum central pressure is 1000 mb. Peak seas are near 18 ft near the center. Numerous moderate to strong convection is near and east of the center within 240 nm, while scattered moderate convection is seen farther northeast and east from 19N to 27N between 33W and 39W. Margot is expected to gradually turn toward the N-NW to N with little change in forward speed through Mon night. Gradual strengthening is forecast over the next few days, and Margot is forecast to become a hurricane near 28.2N 40.8W Mon night. Margot will move north of the area Tue night. 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... An eastern Atlantic tropical wave is analyzed along 27W from 18N to 08N, with a 1011 mb low center (Invest AL97) near 13N27W. It is moving westward at 5 to 10 kt. Scattered moderate isolated strong convection is noted from 13N to 15N between 28W and 30W. Environmental conditions are marginally favorable for additional development on this low pressure system as it slowly moves westward. There is a low chance of tropical cyclone formation during the next 7 days. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic near Nouakchott, Mauritania then reaches southwestward through the aforementioned AL97 to 13N30W. It resumes farther west from 14N40W to 10N44W. The ITCZ continues westward from 10N44W to 08N52W. Numerous moderate to strong convection is present south of the first monsoon trough segment from 07N to 14N between the Senegal- Guinea coast and 21W. Scattered moderate isolated strong convection is seen from 07N to 11N between 32W and 46W. The eastern end of the East Pacific monsoon trough is triggering numerous heavy showers and scattered thunderstorms across the Caribbean waters just north of Panama and northwestern Colombia to the south of 12.5N. ...GULF OF MEXICO... A very weak stationary front curves westward from the Florida Panhandle through the north-central Gulf to just west of Galveston, Texas. Isolated showers are seen near this front. A surface trough near the west coast of the Yucatan Peninsula is producing scattered showers and isolated thunderstorms across the Bay of Campeche. Modest surface ridging is supporting light to gentle winds and seas at 1 to 2 ft over the eastern Gulf, including the Yucatan Channel. Gentle to locally moderate N to ENE winds and 2 to 3 ft seas prevail for the western Gulf, including the Bay of Campeche. For the forecast, weak ridging will continue to dominate the Gulf waters throughout midweek next week, supporting light to moderate winds and slight to moderate seas. ...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 persists from the Yucatan Channel southeastward to northern Colombia. Divergent southerly winds north of its axis are coupling with modest convergent northeasterly winds to produce scattered showers and isolated thunderstorms across the Gulf of Honduras. A weak trade-wind regime continues across much of the basin, except for moderate to locally fresh trades across the southeast and central portions, where seas of 4 to 7 ft prevail. Mainly gentle E winds and 2 to 4 ft seas exist at the northwestern basin. Gentle to moderate ENE to ESE winds and 3 to 5 ft seas prevail elsewhere in the basin, including the Windward Passage. Large E to E-NE swell generated from Lee is impacting the coastal waters of the northern Leeward Islands, and bleeding through the Caribbean Passages and into the extreme NE Caribbean waters. For the forecast, moderate to fresh trade winds will continue in the central and eastern basin through Mon. Large easterly swell from Lee is dominating the Atlantic waters of the northern Leeward Islands and Puerto Rico this morning, and will gradually become NE and then N today through Tue, allowing this swell to move through the Caribbean Passages and into the northeastern Caribbean waters this afternoon through Wed. ...ATLANTIC OCEAN... Please see the SPECIAL FEATURES section at the beginning for details on Major Hurricane Lee and on Tropical Storm Margot. A surface trough extends northward from the northwest Bahamas to near 30N78W. Widely scattered showers and thunderstorms are noted along and up to 180 nm east of this feature. An upper-level low at the central Atlantic near 30N43W is generating widely scattered moderate convection from 24N to 30N between 41W and 50W. Refer to the Monsoon Trough/ITCZ and Tropical Waves sections for additional weather in the Atlantic Basin. Outside the influence of Lee and Margot, a 1022 mb high near 33N35W is supporting gentle to moderate with locally fresh NE to E winds and 5 to 8 ft seas in mixed swell north of 20N between 30W and 65W. To the west, gentle to locally moderate E to SE winds and seas of 3 to 5 ft are found north of 20N between 65W and the Georgia-Florida coast. Near the Canary Islands, gentle NNE trades and seas at 2 to 4 ft are evident north of 23N between the Africa coast and 30W. Near the Cabo Verde Islands, gentle to moderate with locally fresh WNW to NE winds exist from 14N to 22N between the central Africa coast and 30W. To the south from 06N to 14N between the Guinea-Liberia coast and 30W, light to gentle monsoonal winds and 5 to 8 ft seas in moderate southerly swell are present. For the tropical Atlantic, gentle with locally moderate trade winds and seas of 6 to 8 ft in mixed swells dominate from 05N to 20N between 30W and the Lesser Antilles. Gentle to moderate southerly winds and seas of 7 to 10 ft in large southerly swell prevail for the remainder of the Atlantic Basin to the NW of Lee. For the forecast W of 55W, Hurricane Lee will reach near near 22.0N 61.5W this afternoon, near 22.8N 62.8W Mon morning, near 23.3N 64.0W Mon afternoon, near 23.6N 65.2W Tue morning, near 23.9N 66.1W Tue afternoon, and near 24.5N 66.9W Wed morning before turning toward the N. Large E to SE swell is dominating the waters east of 72W this morning, and will continue to propagate westward across the Atlc, reaching the central Bahamas and 75W this evening, the NW Bahamas and 78W Mon evening, and the Florida coasts and southeastern U.S. by Tue afternoon. $$ Stripling