000 AXNT20 KNHC 141747 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Thu Sep 14 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 1600 UTC. ...SPECIAL FEATURES... Hurricane Lee is centered near 31.0N 68.4W at 14/1800 UTC or 200 nm WSW of Bermuda, moving N at 12 kt. Estimated minimum central pressure is 957 mb. Maximum sustained wind speed is 75 kt with gusts to 90 kt. Lee is a very large hurricane. Hurricane force winds extend outward up to 80 NM from the center, and tropical storm force winds extend outward up to 270 NM from the center. Seas of 12 ft or greater extend outward from the center 435 NM NE quadrant, 450 NM SE quadrant, 390 NM SW quadrant and 450 NM NW quadrant with peak seas to 47 ft. A Saildrone - an uncrewed vessel - just reported 26 ft significant wave height at 29.4N 66.7W. Numerous moderate and isolated strong convection is noted within 120 NM of the center. A turn toward the north-northeast and then northeast is forecast Saturday night and Sunday. On the forecast track, the center of Lee will pass west of Bermuda today and tonight, approach the coast of New England and Atlantic Canada Friday and Saturday, and move across Atlantic Canada Saturday night and Sunday. Weakening is forecast, but Lee is expected to remain a large and dangerous hurricane for the next couple of days. Hurricane Margot is centered near 36.5N 39.8W at 14/1500 UTC or 620 nm W of the Azores, moving NNE at 5 kt. Estimated minimum central pressure is 978 mb. Maximum sustained wind speed is 70 kt with gusts to 85 kt. Large swell of up to 10 ft continues north of 25N between 36W-55W. The winds at least 25 kt associated with Margot will remain N of 31N for the remainder of the cyclone's lifetime. 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 Lee and Margot NHC Forecast/Advisory and Public Advisories at www.hurricanes.gov for more details. Invest AL97 in the Central Tropical Atlantic: Showers and thunderstorms associated with a broad low pressure area located around 13N39W have increased and become a little better organized since yesterday. Environmental conditions are expected to be conducive for additional development, and this system is likely to become a tropical depression during the day or so while it moves west-northwestward to northwestward at 10 to 15 kt across the central tropical Atlantic. The chance of this feature developing into a tropical cyclone during the next 48 hours is high. Peak winds forecast are 25 kt and peak seas of 12 ft through 48 hr in connection with this system. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...TROPICAL WAVES... An Atlantic Ocean tropical wave previously along 33W has merged with the tropical wave associated with Invest AL97 along 39W, from 19N southward, moving westward at 10-15 knots. Scattered moderate to strong convection is noted from 10N-15N between 28W- 35W. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Guinea Bissau near 13N17W 14.5N17W to AL97 low pressure near 13N39W to 10N50W. Outside of convection described above, scattered to numerous moderate to strong convection is from 18N-25W between 43W-47W and from 05N-12N east of 26W. ...GULF OF MEXICO... A stationary front is draped across the N Gulf coast from the Upper Texas coast at 29N95W to the Florida Panhandle at 30N84W. Scattered moderate convection is noted north of 28N west of 89W. A weak 1015 mb high is centered over the central Gulf of Mexico near 27N89W and light to gentle winds prevail over the Gulf. Seas are 1-3 ft. In the forecast, a weak ridge across the northern Gulf will dominate the basin throughout the forecast period, supporting mainly light to gentle winds N of 24N and gentle to moderate winds S of 24N. Scattered thunderstorms can be expected across the western Yucatan and eastern Bay of Campeche each late afternoon and evening through the period. ...CARIBBEAN SEA... With Hurricane Lee to the north of the Caribbean, a weak surface ridge is present along the spine of the Greater Antilles. The resulting trades are gentle to moderate over the entire Caribbean. 4-7 ft swell are propagating through the Mona Pass this morning into the central and eastern Caribbean, with seas 2- 4 ft elsewhere. In the forecast, Hurricane Lee will slowly weaken as it passes west of Bermuda near 32.2N 68.0W this evening with maximum sustained winds 75 kt gusts 90 kt. Large N-NW swell across the adjacent Atlantic will move through the NE Caribbean Passage will gradually diminish this afternoon and tonight and then decrease quickly Fri. Moderate E trade winds will return to the Caribbean on Fri. ...ATLANTIC OCEAN... Please, read the SPECIAL FEATURES section, for details about Hurricane Lee, Hurricane Margot, and the INVEST AL97. A weak 1024 mb high is centered just north of our waters near 34N27W with a ridge extending west-southwestward to 27N45W. Trades are moderate to fresh from the ridge equatorward to the monsoon trough with seas of 5-9 ft. South of the monsoon trough and ITCZ winds are gentle to moderate with seas 5-7 ft. Farther west over the southwestern North Atlantic, the winds are dominated by the circulation of Lee with cyclonic winds extending all the way from north of 20N between 60W-80W. Notably the N to NW winds over Florida, the Florida Straits, and the Bahamas are not due to a cold front passage, but instead the circulation of Lee. For the forecast W of 55W, Hurricane Lee will slowly weaken as it passes west of Bermuda near 32.2N 68.0W this evening with maximum sustained winds 75 kt gusts 90 kt, then moves farther north to near 35.0N 67.2W Fri morning and eventually weaken as an extratropical cyclone well north of the area over the NW Atlantic by Sat evening. Long-period swell generated by Lee is expected to impact all waters north through east of the Bahamas through the weekend. High pressure will build across the area late Fri through Sun. Low pressure across the eastern Atlantic, AL97, will approach the far eastern part of the area Mon and Mon night, possibly as a tropical cyclone. $$ CWL/JA