Atlantic Tropical Weather Discussion
603 AXNT20 KNHC 210846 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1215 UTC Mon Sep 21 2026 Tropical Weather Discussion for North America, Central America Gulf of America, 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 0830 UTC. ...TROPICAL WAVES... An eastern Atlantic tropical wave has its axis near 30W, south of 18N, moving eastward at around 10 to 15 kt. No significant convection is noted with this wave. A central Atlantic tropical wave has its axis near 46W, south of 21N, drifting slowly westward. Scattered moderate convection is active on the northern end of the tropical wave from 18N to 21N between 43W and 45W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends off the coast of Africa near 15N17W to 09N25W. The ITCZ extends from 07N30W to 04N50W. Scattered moderate convection is noted from 10N to 15N and east of 20W. ...GULF OF AMERICA... A weak pressure gradient prevails across the area generating light to gentle winds and slight seas across the Gulf. An upper low centered over west-central Florida is supporting clusters of showers and thunderstorms south of Apalachicola, Florida, and over the Florida Straits. For the forecast, weak surface ridging across the southeastern U.S. will maintain generally gentle to moderate winds across the basin through midweek. A vigorous upper-level low and associated surface trough over the southern Gulf will contribute to scattered showers and thunderstorms over the eastern Gulf through midweek, with the Straits of Florida the most active area. A cold front may sink into the northern Gulf Thu night through Fri, leading to a modest increase in winds across the basin. ...CARIBBEAN SEA... A relatively weak pressure pattern is across the basin. Moderate to fresh winds and moderate seas prevail east of 80W. Light to gentle winds and slight to moderate seas prevail west of 80W. An upper trough reaches from the eastern Gulf into the northwest Caribbean. Divergent flow aloft on the southeast side of the upper trough is supporting clusters of showers and thunderstorms between Nicaragua and Jamaica, and off western Cuba. For the forecast, a modest pressure gradient between weak high pressure currently near Bermuda and the Colombian Low will maintain moderate to fresh trade winds over the south-central Caribbean through the week. A vigorous upper-level low over the eastern Gulf of America will continue to promote scattered to numerous showers and thunderstorms over the west and northwestern Caribbean through midweek. ...ATLANTIC OCEAN... For awareness purposes, Tropical Storm Fay is centered near 33.8N 32.1W at 21/0900 UTC or 350 nm SW of the Azores, moving SSE at 2 kt. Estimated minimum central pressure is 995 mb. Estimated minimum central pressure is 997 mb. Maximum sustained wind speed is 55 kt with gusts to 65 kt. An upper trough reaches from the eastern Gulf into the northwest Caribbean. Divergent flow aloft on the southeast side of the upper trough is supporting clusters of showers and thunderstorms from the Florida Straits, southeast Florida, and across the central and southern Bahamas. A weak pressure gradient prevails across the discussion waters. Light to gentle winds prevail across the waters west of 45W, except reaching moderate speeds near the central and southern Bahamas. Slight to moderate seas prevail over these waters. E of 45W, gentle to moderate winds and moderate seas prevail. For the forecast west of 55W, a very weak pressure gradient across the western Atlantic will promote variable gentle to moderate winds across forecast waters through early Thu. A vigorous upper-level low over the Gulf of America and Florida, and abundant tropical moisture across the Atlantic will force scattered showers and thunderstorms across the waters west of 70W through Wed. Low pressure will deepen offshore of the middle Atlantic coast of the U.S. late Wed through Fri, allowing a cold front to move into the far NW waters and N Florida Thu through Fri. The front will be accompanied by increasing winds and the potential for large N-NE swell. Meanwhile, Tropical Storm Fay will move to 33.2N 32.3W this afternoon, 32.3N 33.2W Tue morning, and 31.2N 34.9W Tue afternoon. Fay will weaken to a remnant low near 30.4N 36.7W Wed morning, then 29.8N 38.4W Wed afternoon, and 29.6N 40.1W Thu morning. Fay will change little in intensity as it moves to 29.5N 43.0W by early Fri.