Atlantic Tropical Weather Discussion
999 AXNT20 KNHC 201000 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1215 UTC Tue Oct 20 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 0930 UTC. ...SPECIAL FEATURES... Atlantic Significant N Swell: A 1001 mb low pressure centered between the Outer Banks and Bermuda continues to produce a large area of strong to gale-force winds north of our area. A cold front extends from this low to 34N63W and continues as a stationary front to 31N67W and to the Florida Straits. Fresh to locally strong northerly winds and rough to very rough seas, peaking around 14 ft, are noted behind the front south of 31N. These seas will subside below 12 ft this morning. Seas to 8 ft will persist thereafter over the waters west of 65W and north of 25N through Thu night. Please read the latest High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers FZNT02 KNHC/HSFAT2 or at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for further details. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic through the coast of Senegal near 14N17W and continues west-southwestward to 09N25W. The ITCZ extends from 09N25W to 09N60W. Scattered moderate to isolated strong convection is observed from 08N to 12N and east of 25W. ...GULF OF AMERICA... Scattered showers and tstms persist this morning over the southwest Gulf and off the Yucatan Peninsula, along a trough reaching from north of Tampico, Mexico to Ciudad del Carmen, Mexico. A recent scatterometer satellite pass captured strong winds off Veracruz, where seas are estimated to be 8 ft. Elsewhere, 1028 mb high pressure centered over the Ohio Valley is supporting moderate to fresh NE winds and mainly 5-7 ft seas across the Gulf. For the forecast, the high pressure over the eastern U.S. will continue to support fresh to NE winds are across the basin through the latter part of the week, except for strong NW to N winds over the SW Gulf offshore Veracruz through Wed. Looking ahead, strengthening high pressure over the eastern U.S. will support strong to near-gale NE winds and rough seas over the eastern Gulf Sat. ...CARIBBEAN SEA... Trade wind convergent and favorable divergent flow aloft is supporting scattered showers and thunderstorms across the southwest Caribbean from Colombia to Nicaragua. An upper trough is also supporting a few thunderstorms from Jamaica to Grand Cayman and in the Windward Passage. High pressure over the eastern U.S. is maintaining moderate to fresh NE to E winds across the Yucatan Passage. Elsewhere, relatively weak pressure gradient is supporting only limited fresh trade wind flow off Colombia with 4-6 ft seas, with gentle to moderate trade winds and 2-4 ft elsewhere. For the forecast, the high pressure over the eastern U.S. will continue to support moderate to fresh NE winds across the far northwest Caribbean and Yucatan Channel through late today. These winds will diminish by mid week as the high pressure weakens, leaving gentle to moderate winds and slight to moderate seas across the basin through mid week. Looking ahead, expect moderate to fresh winds across the south-central Caribbean by Thu, and fresh winds across the far northwest Caribbean by late Sat as high pressure builds again north of the area. ...ATLANTIC OCEAN... See the Special Features section above for information on significant north swell behind a cold front in the western Atlantic. A broad upper-level low near 25N52W is producing a large area of showers and thunderstorms from 20N to 31N and between 43W and 57W. A surface trough reaches from 28N49W to 1010 mb low pressure near 25N56W to 21N60W. This pattern is supporting moderate to locally strong easterly winds and seas of 6-9 ft north of 26N and between 45W and 55W. Farther east, scattered showers and thunderstorms are active along a weak surface trough extends from the Canary Islands to 1012 mb low pressure near 27N21W to 24N25W. Gentle to moderate winds and 4-6 ft are noted elsewhere across the basin. For the forecast west of 55W, moderate to fresh N to NE winds and large NE swell persist west of a stationary reaching from 31N67W to the central Bahamas to northwest Cuba. Winds will diminish tonight into Wed as the front dissipates, and lingering swell will subside through Thu. Looking ahead, a tightening pressure gradient developing late Fri is expected to induce widespread near to gale-force NE winds over the waters north of about 25N well into the weekend. Seas with these winds are expected to quickly build to rough to very rough. Mariners should monitor the latest marine forecasts, and have avoidance plans in place.