Atlantic Tropical Weather Discussion
466 AXNT20 KNHC 122233 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0015 UTC Sun Sep 13 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 1800 UTC surface analysis and satellite imagery through 2230 UTC. ...SPECIAL FEATURES... Caribbean Gale Warning: Recent scatterometer data indicate fresh to strong winds over the central Caribbean, with near gale-force winds offshore Colombia. Seas are near 13 ft with the strongest winds based on recent altimeter data. Buoy 42058 located at 14N76W is reporting seas of 10-11 ft. A tight pressure gradient between a subtropical ridge north of the islands and lower pressures associated with the Colombian Low supports these wind speeds. These marine conditions are forecast to persist for the next several days. Winds will pulse to gale force tonight offshore Colombia, where a Gale Warning has been issued. Please read the latest High Seas Forecast issued by the National Hurricane Center at website: https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml ...TROPICAL WAVES... The axis of a tropical wave is near 43W from 06N to 20N, moving westward at around 20 kt. Scattered showers are seen near the wave axis. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic through the coast of Senegal near 14N17W, and continues westward to 10N24W to 12N35W to 10N45W. The ITCZ extends from 10N45W to the coast of NE Venezuela near 10N61W. Scattered moderate convection is noted from 08N to 13N between 44W and 61W. ...GULF OF AMERICA... Convection continues to develop over the Gulf region, mainly north of 26N, and over most of the Florida Peninsula as abundant tropical moisture remains in place. A diffluent pattern aloft is also helping to induce this convective activity. A surface trough is just E of SE Florida while another trough is over the central Bay of Campeche. Under this weather pattern, gentle to moderate winds with slight to moderate seas are noted. For the forecast, weak high pressure will bring relatively tranquil conditions to Gulf waters into the start of next week. The exception will be the Bay of Campeche, where a diurnal trough will move westward offshore the Yucatan Peninsula each evening, bringing nightly pulses of fresh NE winds. Starting later Tue, stronger high pressure building southward from the eastern United States will lead to increasing NE to E winds over the basin, with speeds reaching fresh to strong over the NE basin Wed and Thu. ...CARIBBEAN SEA... As previously mentioned, the pressure gradient between surface ridging over the western Atlantic and the Colombian low supports fresh to near gale-force easterly trade winds and rough seas over much of the central Caribbean, mainly S of 18N. Moderate to fresh easterly winds and moderate seas are found in the eastern Caribbean, while moderate or weaker winds and slight seas are prevalent elsewhere. An upper-level trough over the NW Caribbean is helping to induce convection over western Cuba and the NW Caribbean. Scattered showers and thunderstorms are noted over the remainder of the Greater Antilles due to local effects. For the forecast, a tight pressure gradient between a subtropical ridge north of the islands and lower pressures associated with the Colombian Low will continue to support strong to near-gale easterly trade winds and rough to locally very rough seas over the central Caribbean for the next several days. Winds will pulse to gale force tonight offshore Colombia, where a Gale Warning has been issued. Strong winds are expected tonight and Sun night in the Gulf of Honduras. Meanwhile, moderate to fresh easterly breezes are expected over the next few days in the eastern Caribbean. ...ATLANTIC OCEAN... An upper-level low located just N of Hispaniola, combined with upper diffluent over Florida and the far western Atlantic supports a band-like of showers and thunderstorms that roughly covers the area from 24N to 27N W of 55W. Farther E, another area of showers and thunderstorms is noted affecting the waters from 24N to 30N between 39W and 43W. This convective activity is related to a surface trough, that runs from 30N40W to 22N41W. A frontal trough remains over the forecast area, and extends from 31N44W to 26N55W to just south of Bermuda. A weak 1017 mb low is analyzed along the front and SE of Bermuda near 30N61W. The remainder of the forecast region is dominated by high pressure, with the main center of 1025 mb located well NE of the Azores. The pressure gradient between the high pressure and lower pressures over NW Africa is promoting moderate to fresh N to NE winds N of 20N and E of 30W, including the Canary Islands. Moderate to fresh trade winds are observed E of the Lesser Antilles to about 45W, and also just N of Hispaniola. Moderate or weaker winds prevail elsewhere. Seas are in general moderate across the Atlantic forecast waters based on altimeter data and Sofar buoys. Of note: A gale-force gap wind event is occurring in the Straits of Gibraltar. For the forecast west of 55W, the subtropical ridge will continue to dominate through Mon night, bringing mainly tranquil marine conditions. However, trades north of Hispaniola into the Windward Passage will be fresh to locally strong into Monday. On Tue, strong high pressure building SE through the eastern United States will bring a cold front into the NW waters, increasing NE winds to fresh to strong and causing seas to build to rough N of the Bahamas and W of 70W Tue night through Wed night.