{"msg": "138\nAXNT20 KNHC 150950\nTWDAT \nTropical Weather Discussion\nNWS National Hurricane Center Miami FL\n1215 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 0600 UTC surface analysis and satellite imagery through \n0925 UTC.\n...TROPICAL WAVES...\nA sharp tropical wave is along 55W, south of 21N, moving westward\nat 10-15 kt. Scattered moderate isolated strong convection is \nobserved from 10N to 21N and between 47W and 57W. \n...MONSOON TROUGH/ITCZ...\nThe monsoon trough enters the Atlantic along the coast of Guinea \nnear 11N15W and continues to 08N36W. The ITCZ extends from 08N37W\nto 11N54W. Scattered moderate to isolated strong convection is \nnoted from 04N to 17N and east of 25W.\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 NE Gulf supports moderate to fresh SE-E winds and moderate\nseas in the Bay of Campeche and in the western Gulf, west of 95W.\nElsewhere, light to gentle winds and slight seas 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\nnumerous showers and thunderstorms over the SW Caribbean. This\nenvironment 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 near gale-force\neasterly trade winds and moderate to rough seas across much of \nthe central Caribbean. Moderate to fresh NE-E winds and moderate \nseas are occurring in the eastern Caribbean, Windward Passage and \nlee of 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\ncentral Caribbean, with moderate to fresh trades elsewhere from\n11N to 18N. 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\nnear the Windward Passage and Lee of Cuba through midweek. Winds\nmay diminish across the basin by the end of the week into the\nupcoming weekend as the pressures gradient relaxes, with seas\nalso slightly subsiding.\n...ATLANTIC OCEAN...\nA pre-frontal trough is noted ahead of an approaching cold front\nto the NW waters producing scattered showers and isolated\nthunderstorms north of 28N and between 67W and 75W. Meanwhile, a\nlarge upper-level low over and east of the SE Bahamas is\nsupporting scattered showers south of 25N and between 61W and 75W.\nHigh 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 51W and north of 24N, producing\nnumerous showers and isolated thunderstorms north of 26N and\nbetween 45W and 61W. 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 30W and\n60W. Moderate or weaker winds and moderate seas are prevalent \nelsewhere.\nFor the forecast west of 55W, a cold front is approaching the\nwaters off NE Florida and then will become stationary from \nBermuda to the NW Bahamas into Wed. A tight pressure gradient \nbetween the building ridge over the eastern United States and the \nfront will result in fresh to locally strong NE winds and seas to \nbuild to rough N of the Bahamas and W of 70W through early Thu. \nConditions will improve later Thu into Fri. During the middle to \nlater portion of the week, a trough of low pressure is forecast to\nmove west- northwestward into the NE portion of the waters, \nbringing thunderstorms while also weakening the high and pressure \ngradient.\n", "title": "Atlantic Tropical Weather Discussion", "id": "1210434867846807554", "issued": "2026-09-15T12:15:00Z", "wmo": "AXNT20", "source": "NOAA/NWS National Hurricane Center, received via the National Weather Wire Service", "page": "https://hurricane.terrapin.com/text/1210434867846807554"}