000 AXNT20 KNHC 110556 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Mon Sep 11 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... Hurricane Lee is centered near 22.6N 62.2W at 11/0300 UTC or 270 nm N of the Northern Leeward Islands, and moving NW at 7 kt. Estimated minimum central pressure is 950 mb. Maximum sustained winds are 105 kt with gusts to 130 kt. Peak seas range from 39 to 41 ft near the center. Numerous moderate to scattered strong convection is within 70 nm of the center. Scattered moderate convection is seen farther north from 24N to 26N between 58W and 65W, and farther east from 20N to 24N between 58W and 61W. Lee is expected to continue its current motion for the next few days, passing well north of the northern Leeward Islands, Virgin Islands, and Puerto Rico during the next day or two. Lee remains a category 3 hurricane on the Saffir-Simpson Hurricane Wind Scale. Additional strengthening is forecast for the next day or so, then followed by a gradual weakening trend. Swells generated by Lee are affecting the Leeward and Virgin Islands, Puerto Rico, Hispaniola, the Turks and Caicos Islands, the Bahamas, and Bermuda. These swells are likely to cause life-threatening surf and rip current conditions. Dangerous surf and rip currents have begun to reach portions of the southeast U.S. East Coast and are forecast to worsen and spread northward along much of the U.S. East Coast during the next couple of days. Please consult products from your local weather office. Tropical Storm Margot is centered near 24.6N 39.9W at 11/0300 UTC or 1030 nm WNW of the Cabo Verde Islands, and moving N at 7 kt. Estimated minimum central pressure is 996 mb. Maximum sustained winds are 55 kt with gusts to 65 kt. Peak seas range from 19 to 21 ft near the center. Scattered moderate convection is within 50 nm of the center. Similar conditions is found near a banding feature farther northeast and southeast from 20N to 34N between 34W and 38W. Margot is expected to continue its current motion for the next several days. Additional strengthening is forecast, and Margot is likely to become a hurricane on Monday. 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 far eastern Atlantic tropical wave is near 19W from 18N southward, and moving west around 5 kt. Widely scattered moderate convection is from 08N to 15N between the Senegal-Guinea Bissau coast and 24W, including the southern Cabo Verde Islands. Environmental conditions appear conducive for gradual development of this system during the latter part of this week, and a tropical depression could form by next weekend as it moves westward to west-northwestward over the central tropical Atlantic. There is a low chance of tropical cyclone formation during the next 2 days and a medium chance from 3 to 7 days. An eastern Atlantic tropical wave is near 29W from 18N southward through a 1012 mb low (Invest AL97) near 14N29W, and moving westward around 10 kt. Widely scattered moderate convection is noted from 09N to 15N between 27W and 34W. This system is forecast to merge with the aforementioned tropical wave upstream in a couple of days. As a result, there is a low chance of tropical cyclone formation during the next 7 days. ...MONSOON TROUGH/ITCZ... A monsoon trough enters the Atlantic near Nouakchott, Mauritania then reaches southwestward through the low (Invest AL97) near 14N29W to 15N34W. It resumes farther west from 14N41W to 08N49W. Other than convection associated with the two tropical waves, there is no additional convection near the monsoon trough. No ITCZ is present based on the latest analysis. ...GULF OF MEXICO... A very weak stationary front curves westward from the Florida Panhandle through the north-central Gulf to near Corpus Christi, Texas. Isolated thunderstorms are seen near and up to 110 nm south of the front. A surface trough moving off the west coast of the Yucatan Peninsula is triggering scattered showers and thunderstorms at the central and eastern Bay of Campeche. A modest surface ridge is supporting gentle to locally moderate E to SSE winds and 2 to 3 ft seas for the entire Gulf. For the forecast, the surface ridge will continue to dominate the Gulf waters through most of this week with 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 running east-southeastward from western Cuba to Hispaniola is inducing widely scattered showers and isolated thunderstorms from the Gulf of Honduras eastward across Jamaica to Hispaniola. The presence of Hurricane Lee in the Atlantic is sustaining a weak pressure gradient across the basin. Light to gentle winds and 4 to 6 ft seas in moderate easterly swell are present at the northeastern basin, except 6 to 9 ft seas in large easterly swell near the Virgin Islands and Anguilla. Light to gentle winds and seas at 3 to 5 ft in moderate easterly swell are found near Costa Rica and Panama. Gentle to moderate with locally fresh ENE to ESE winds and seas of 3 to 6 ft prevail for the rest of the basin. For the forecast, moderate to fresh trade winds will continue in the central and eastern basin through Mon before Lee in the Atlantic disrupts the pressure pattern. Large easterly swell from Lee is dominating the Atlantic waters from the northern Leeward Islands to the Central Bahamas. This large swell from Lee will gradually become NE and then N tonight through Thu, and move through the Caribbean Passages into the Caribbean waters between the Leeward Islands and the Mona Passage, before diminishing significantly Thu night through Fri. ...ATLANTIC OCEAN... Please see the SPECIAL FEATURES section at the beginning for information about Hurricane Lee and Tropical Storm Margot. An upper-level trough near 27N44W is causing isolated thunderstorms from 25N to 29N between 46W and 51W. A surface trough near 14N48W is generating similar conditions within 100 nm of 14N49W. Refer to the Tropical Waves section for additional convection in the Atlantic Basin. Outside the direct impact of Lee and Margot, a modest 1022 mb high near 32N32W is supporting gentle to moderate NE to SE winds and seas of 6 to 12 ft in mixed large swells north of 20N between 30W and 70W. Farther west, light to gentle with locally moderate ENE to ESE winds exist north of 20N between 70W and the Georgia- Florida coast. Near the Canary Islands, gentle to moderate NNE to NE trades and 4 to 6 ft seas are evident north of 18N between the northwest Africa coast and 30W. To the south, light to gentle with locally moderate monsoonal winds and seas at 4 to 6 ft in mixed moderate swells are noted from 07N to 18N/20N between the central Africa coast and 35W, including the Cabo Verde Islands. For the tropical Atlantic from 08N to 20N between 35W and the Lesser Antilles, light to gentle winds and 6 to 10 ft seas in mixed moderate to large swells prevail. Gentle to moderate with locally fresh southerly winds and 6 to 9 ft seas in large southerly swell dominate the remainder of the Atlantic Basin. For the forecast W of 55W, Hurricane Lee will reach near 23.1N 63.1W Mon morning, 23.6N 64.4W Mon evening, and 24.1N 65.5W Tue morning. Afterward, it will move to near 24.6N 66.4W Tue evening, 25.3N 67.2W Wed morning, and 26.5N 67.7W Wed evening. Lee is expected to turn northward and enter the northwestern Atlantic Wed night through Thu night. Large E to SE swell dominating the waters east of 75W tonight will continue to propagate westward across the Atlantic, reaching the northwest Bahamas and 78W early Mon evening, and the Florida coasts Tue afternoon. This swell will persist in these waters Tue night through Fri. $$ Forecaster Chan