{"msg": "432\nAXNT20 KNHC 180908\nTWDAT \nTropical Weather Discussion\nNWS National Hurricane Center Miami FL\n1215 UTC Fri Sep 18 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 \n0810 UTC.\n...TROPICAL WAVES...\nA central Atlantic tropical wave has its axis along 37W from 02N \nto 17N, moving westward around 10 kt. Scattered moderate isolated\nstrong convection is from 06N to 175N between 29W and 42W.\nA central Caribbean tropical wave has its axis along 73W from\nportions of Haiti southward to near the border of Colombia and\nVenezuela, moving westward at around 10 kt. Scattered moderate \nconvection is noted from 16N to 19N between 69W and 77W.\n...MONSOON TROUGH/ITCZ...\nThe monsoon trough enters the Atlantic near 18N16W and continues \nsouthwestward to 10N39W, where it transitions to the ITCZ to \nthe border of French Guiana and Suriname at 06N54W. Aside from \nconvection associated to the tropical waves as described above, \nscattered moderate isolated strong is evident south of the monsoon\ntrough to 04N between 18W and 29W.\n...GULF OF AMERICA...\nA frontal trough continues to be analyzed from the NW Bahamas\nsouthwestward to across the Florida Keys and into the SE Gulf to\nthe north of the Yucatan Peninsula. Scattered moderate convection\nis noted from 19N to 25N to the east of 90W. Moderate to fresh\neasterly winds are across the Gulf waters north of 24.5N, along\nwith 4-7 ft seas. Gentle to moderate easterly winds are south of\n24.5N, along with 2-4 ft seas. A weak diurnal surface trough is \nnoted west of the Yucatan Peninsula with another trough offshore \nSE Texas and NE Mexico, supporting scattered showers and \nthunderstorms within 90 nm of Veracruz, Mexico.\nFor the forecast, the pressure gradient between high pressure \nover the southeastern U.S. and a weakening frontal trough over the\nSE Gulf supports fresh NE to E winds and moderate seas over the \nnorthern Gulf. These conditions will gradually improve later today\ninto Sat. Meanwhile, a rather broad upper-level low will move \ntowards Florida from the western Atlantic today, and into the NE \nGulf on Sat. This feature will lead to increasing shower and \nthunderstorm activity over Florida, and then over the eastern and \ncentral Gulf waters. Fairly tranquil marine conditions are \nforecast by the end of the weekend into early next week. \n...CARIBBEAN SEA...\nPlease refer to the tropical wave section for details on a wave in\nthe central Caribbean including associated convection.\n \nThe pressure gradient between weakening high pressure over the \nwestern Atlantic and relatively lower pressure in northern South \nAmerica is allowing for fresh to strong trades over the central \nCaribbean from 11N to 18N between 64W and 76W, where seas are 6-9\nft. Moderate to fresh trades are found elsewhere from 10N to 19N \nto the east of 80W, along with 4-7 ft seas. Gentle to moderate\nwinds and 2-5 ft seas prevail across the remainder of the basin.\nUpper-level divergence east of an upper-level low that is over the\nnorthern Yucatan Peninsula is supporting scattered showers and \nisolated thunderstorms over the northwestern Caribbean. An upper-\nlevel disturbance riding along a jet stream branch is keeping \nactive weather in the form of numerous moderate convection over \nthe waters from 16N to 20N west of 76W.\nFor the forecast, the pressure gradient between high pressure \nover the western Atlantic and the Colombian Low will generally \nmaintain fresh to strong trades along with moderate to locally \nrough seas over most of the central Caribbean through Sat. Winds \nwill diminish to moderate to fresh speeds thereafter as the \npressure gradient relaxes across the area. Moderate or weaker \nwinds and slight to moderate seas are forecast elsewhere. \n...ATLANTIC OCEAN...\nA stationary front extends from near 31N72W southwestward to\nacross the NW Bahamas and to the Florida Keys. Moderate to locally \nfresh northeast winds and 4-6 ft seas are north of of the front. \nScattered moderate convection is seen north of about 23N and east\nof the front to around 68W. Well to the east, fresh to strong N-NE\nwinds and 6-9 ft seas are found from 17N to 22N between Africa \nand 21W due to a tight pressure gradient, with moderate to fresh \nN-NE winds and 6-9 ft seas elsewhere from 16N to 31N to the east\nof 28W. Moderate or weaker winds and moderate seas dominate the\nremainder of the tropical Atlantic waters.\nOther than the convection described above with the tropical wave\nin the central Atlantic and the monsoon trough, scattered moderate\nisolated strong is found from 22N to 26N between 29W and 42W, and\nfrom 25N to 31N between 41W and 54W where a couple of surface\ntroughs are present.\nFor the forecast west of 55W, a stationary front that extends \nfrom near Bermuda to the NW Bahamas will gradually wash out today.\nConditions will improve early on Fri as high pressure becomes the\ndominant feature across the basin into the weekend into early \nnext week. Meanwhile, abundant tropical moisture, combined with an\nupper- level low located east of Florida, will continue to \nsupport scattered to numerous showers and thunderstorms, mainly W \nof 70W, through at least Sun. \n", "title": "Atlantic Tropical Weather Discussion", "id": "1211276059096088578", "issued": "2026-09-18T12:15:00Z", "wmo": "AXNT20", "source": "NOAA/NWS National Hurricane Center, received via the National Weather Wire Service", "page": "https://hurricane.terrapin.com/text/1211276059096088578"}