{"msg": "693\nAXNT20 KNHC 151543\nTWDAT \nTropical Weather Discussion\nNWS National Hurricane Center Miami FL\n1815 UTC Tue Sep 15 2026\nTropical Weather Discussion for North America, Central America\nGulf of America, Caribbean Sea, northern sections of South\nAmerica, and Atlantic Ocean to the African coast from the\nEquator to 31N. The following information is based on satellite\nimagery, weather observations, radar and meteorological analysis.\nBased on 1200 UTC surface analysis and satellite imagery through \n1543 UTC.\n...TROPICAL WAVES...\nA well defined tropical wave is along 56W, south of 21N, moving \nwestward at 10-15 kt. Moderate to fresh E winds along with seas \n4 to 6 ft are found in the vicinity of the wave. Scattered \nmoderate to isolated strong convection is observed from 11N to 21N\nand between 51W and 59W. \n...MONSOON TROUGH/ITCZ...\nThe monsoon trough enters the Atlantic near 13N17W and continues \nto 07N45W. The ITCZ extends from 07N45W to 10N54W. Scattered \nmoderate to isolated strong convection is noted from 05N to 20N \nand east of 26W.\n \n...GULF OF AMERICA...\nA few showers and isolated thunderstorms are occurring in the\neastern Gulf waters and off Veracruz. A weak high pressure over\nthe N Gulf supports moderate E to SE winds and 3 to 5 ft seas in \nthe Bay of Campeche. Elsewhere, light to gentle winds and slight \nseas prevail.\nFor the forecast, a strong high pressure over the eastern United \nStates will build southward behind a weakening cold front that \nwill spread across the eastern Gulf waters. The tighter pressure \ngradient will support fresh to locally strong NE-E winds and rough\nseas starting in the NE Gulf tonight and spreading over the \nnorthern Gulf waters through Thu night. Elsewhere, a diurnal \ntrough will move westward offshore the Yucatan Peninsula each \nevening through Thu night, bringing nightly pulses of fresh to \nlocally strong NE winds. Conditions will improve across the basin \nFri, allowing for moderate or weaker winds and slight to moderate \nseas during the weekend. \n...CARIBBEAN SEA...\nThe interaction between an large upper-level low pressure system\nover the north-central Caribbean and tropical moisture support\nscattered showers and isolated thunderstorms south of Puerto Rico.\nThis environment is also generating a few showers in the eastern \nCaribbean, bringing some rain to Puerto Rico and the Virgin \nIslands. \nHigh pressure north of the area sustains fresh to strong easterly\ntrade winds and moderate to rough seas across much of the central\nCaribbean. Moderate to locally fresh NE-E winds and moderate seas\nare occurring in the eastern Caribbean, Windward Passage and lee \nof Cuba. Elsewhere, moderate or weaker winds and moderate seas \nprevail.\nFor the forecast, tight pressure gradient between the subtropical\nridge located north of the islands and lower pressures in \nColombia will support fresh to locally near gale-force easterly \ntrade winds and moderate to rough seas across much of the central \nCaribbean, with moderate to fresh trades elsewhere from 11N to \n18N. These conditions will persist through the workweek. \nElsewhere, moderate or lighter winds and slight to moderate seas \nare expected, except moderate to fresh mainly in the evenings near\nthe Windward Passage and Lee of Cuba through midweek. Winds may \ndiminish across the basin by the end of the week into the upcoming\nweekend as the pressures gradient relaxes, with seas also \nslightly subsiding. \n...ATLANTIC OCEAN...\nA pre-frontal trough is noted ahead of an approaching cold front\nover the NW waters producing scattered showers and isolated \nthunderstorms north of 27.5N and between 68W and 76W. Meanwhile, \na large upper-level low over and east of the SE Bahamas is \nsupporting scattered showers south of 26N and between 61W and \n72W. High pressure dominates the rest of the SW North Atlantic, \nsustaining moderate or weaker winds and slight to moderate.\nAnother upper-level low over the central Atlantic interacts with a\nsurface trough analyzed along 51.5W and north of 26N, producing \nnumerous showers and isolated thunderstorms north of 26N and \nbetween 46W and 54W. Environmental conditions are forecast to \nbecome more conducive for development in a few days, and a \ntropical depression could form late this week as the system moves \nslowly west-northwestward over the subtropical Atlantic. The \nsystem has a medium chance of formation over the next 7 days. A \nstrong subtropical ridge centered north of the Azores extends \nsouthward into the central and eastern Atlantic, supporting \nmoderate to fresh easterly winds and moderate seas between 25W \nand 53.5W. Moderate or weaker winds and moderate seas are \nprevalent elsewhere.\nFor the forecast west of 55W, a cold front is approaching the \nwaters off NE Florida and then will become stationary from Bermuda\nto the NW Bahamas into Wed. A tight pressure gradient between the\nbuilding ridge over the eastern United States and the front will \nresult in fresh to locally strong NE winds and seas to build to \nrough N of the Bahamas and W of 70W through early Thu. Conditions \nwill improve later Thu into Fri. During the middle to later \nportion of the week, a trough of low pressure is forecast to move \nwest- northwestward into the NE portion of the waters, bringing \nthunderstorms while also weakening the high and pressure gradient.\n\n", "title": "Atlantic Tropical Weather Discussion", "id": "1210504342778806274", "issued": "2026-09-15T18:15:00Z", "wmo": "AXNT20", "source": "NOAA/NWS National Hurricane Center, received via the National Weather Wire Service", "page": "https://hurricane.terrapin.com/text/1210504342778806274"}