000 AXNT20 KNHC 080558 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Fri Sep 8 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 0000 UTC surface analysis and satellite imagery through 0500 UTC. ...SPECIAL FEATURES... Major Category Five Hurricane Lee is centered near 17.3N 52.4W at 08/0300 UTC or 610 nm east of the Northern Leeward Islands, and moving WNW at 12 kt. Estimated minimum central pressure is 928 mb. Maximum sustained winds are 140 kt with gusts to 170 kt. Peak seas near the center are from 27 to 29 ft. Seas 12 ft or greater extend outward from the center up to 210 nm NE quadrant, 150 nm NE and SE quadrants, and 90 nm SW quadrant. Numerous scattered to isolated strong convection are seen up to 70 nm in a NW semicircle, and 100 nm in a SE semicircle. Lee is forecast to maintain its WNW movement through early next week with a significant decrease in forward speed by Sat. while gradually slowing down its forward speed. Lee is expected to pass well north of the Virgin and northern Leeward Islands, and Puerto Rico near Sun. Additional strengthening is expected overnight, then follows by some fluctuations in intensity afterward but Lee is forecast to remain a major hurricane through early next week. Large swells generated by Lee should reach the Leeward Islands by Fri night, and the Virgin Islands, Puerto Rico and Hispaniola this weekend, and finally the Bahamas and Bermuda by Mon. Long- period swell well west and northwest of Lee are likely to cause dangerous surf and rip currents along most of the U.S. East Coast beginning Sun. Please consult products from your local forecast weather office. Tropical Storm Margot is centered near 16.8N 29.3W at 08/0300 UTC or 310 nm west of the Cabo Verde Islands, and moving WNW at 14 kt. Estimated minimum central pressure is 1004 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Peak seas are from 28 to 30 ft near the center with seas 12 ft or greater extending outward up to 30 nm in a northern semicircle. Scattered moderate convection are found near the center and up to 170 nm in a northern semicircle. Margot is forecast to maintain its current motion through this weekend, then turn toward the northwest early next week. A gradual strengthening trend is anticipated for the next few days, and Margot could become a hurricane over 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 NHC Forecast/Advisory and Public Advisory on Lee and Margot at www.hurricanes.gov for more details. ...MONSOON TROUGH/ITCZ... A monsoon trough enters the Atlantic near the Mauritania/Senegal border and extends southwestward to 14N19W, then continues from 10N30W to 06N39W. Scattered showers and isolated thunderstorms are occurring near the first segment from 10N to 20N between Mauritania-Senegal coast and 20W. Widely scattered moderate convection is noted near and south of the second segment from 2N to 8N between 30W and 37W. There is no ITCZ present based on the latest analysis. The eastern end of the East Pacific monsoon trough is triggering scattered showers and isolated thunderstorms over the Caribbean waters near Costa Rica and Panama. ...GULF OF MEXICO... A surface trough curves southeastward from just southwest of New Orleans to the east-central Gulf. Scattered showers and thunderstorms are present near the Louisiana coast. Otherwise, a modest surface ridge related to a 1012 mb high at the northwestern Gulf dominate much of the Gulf. Light to gentle winds and 1 to 2 ft seas are evident across the central and eastern Gulf, including the Yucatan Channel. Gentle to locally moderate E to SE winds with seas at 2 to 3 ft prevail at the western Gulf. For the forecast, the high and associated surface ridge will continue to dominate the region with light to moderate winds through midweek next week. ...CARIBBEAN SEA... A broad upper-level trough over central Cuba is inducing scattered moderate convection at the northwest basin, and near Hispaniola and Puerto Rico. A modest trade-wind regime are present across much of the basin. Moderate to fresh ENE to E winds and seas of 5 to 7 ft are noted at the south-central basin. Gentle to moderate NE to E winds with 3 to 5 ft seas are evident at the eastern, north-central and southwestern basin, except near Costa Rica and Panama where light to gentle winds and 4 to 5 ft seas in moderate easterly swell are present. Gentle to moderate E winds and seas at 2 to 4 ft prevail at the northwestern basin. For the forecast, Hurricane Lee is expected to strengthen further through Fri morning, and move to near 18.1N 54.0W Fri morning and near 19.1N 56.1W Fri evening. It will reach near 20.1N 58.0W Sat morning, 20.9N 59.6W Sat evening, 21.5N 60.9W Sun morning and 22.1N 62.2W Sun evening. In the Caribbean, moderate to fresh trade winds will continue in the central and eastern basin into the weekend. Large E to NE swell produced by Lee will reach the passages of the northeastern Caribbean early Sat, then the Mona Passage Sun night. ...ATLANTIC OCEAN... Please see the SPECIAL FEATURES section at the beginning for information about Hurricane Lee and Tropical Storm Margot. A surface trough meander northeastward from the southeast Bahamas to near Bermuda at 31N64W. Scattered showers and isolated thunderstorms are found up to 120 nm along either side of this feature. Convergent easterly winds north of Hurricane Lee are generating widely scattered moderate convection from 23N to 26N between 45W and 53W. An upper-level low in the central Atlantic near 29N44W is producing similar conditions north of 26N between 41W and 45W. Farther southeast, a 1013 mb low and its related surface trough are causing widely scattered showers from 25N to 27N between 33W and 38W. Moderate to fresh NE to E winds and seas of 6 to 8 ft are also found in this area. The following descriptions are outside the areas impacted by Lee, Margot and the 1013 mb low mentioned above. Gentle to locally moderate NNE to E winds and seas of 4 to 6 ft in moderate northerly swell are evident north of 20N between the Africa coast and 65W, including the Canary Islands. Farther west, light to gentle with locally moderate E to SE winds and 3 to 5 ft seas dominate north of 20N between 65W and the Georgia-Florida coast. For the tropical Atlantic, gentle to moderate with locally fresh NE to SSE winds and seas at 5 to 8 ft are seen from 10N to 20N between 20W and the Lesser Antilles. Farther east, light to gentle monsoonal winds and seas of 4 to 7 ft in moderate northerly swell are present north of 10N between the central Africa coast and 20W. Gentle to moderate southerly winds and 6 to 9 ft seas in mixed northerly and southerly swells prevail for the rest of the Atlantic Basin. For the forecast W of 55W, Hurricane Lee is expected to strengthen further through Fri morning, and move to near 18.1N 54.0W Fri morning and near 19.1N 56.1W Fri evening. It will reach near 20.1N 58.0W Sat morning, 20.9N 59.6W Sat evening, 21.5N 60.9W Sun morning and 22.1N 62.2W Sun evening. Large swell from Hurricane Lee will reach waters near 58W Fri morning, then begin to impact the Anegada Passage and adjacent waters Sat afternoon, and the Mona Passage beginning Sun morning. Beyond Sun, Lee is expected to begin to turn more northwest and weaken very slowly. $$ Forecaster Chan