Atlantic Tropical Weather Discussion
091 AXNT20 KNHC 091717 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1815 UTC Fri Oct 9 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 1200 UTC surface analysis and satellite imagery through 1600 UTC. ...SPECIAL FEATURES... Hurricane Isaias is centered near 27.7N 87.3W at 1500 UTC or 170 nm S of Pensacola, FL, moving NNE at 14 kt. Estimated minimum central pressure is 959 mb. Maximum sustained wind speed is 105 kt with gusts to 130 kt, making Isaias a major hurricane. Numerous moderate to scattered strong convection is across the eastern Gulf N of 26.5N between 85W and 88.5W, with the strongest storms within 90 nm of the center of Isaias. Seas near the center are up to 33 ft. A general northward motion is expected throughout the remainder of today, with landfall expected within the warning area tonight or early Saturday. Little change in strength is anticipatedbefore landfall, and Isaias will likely remain a dangerous hurricane until landfall. Swells from Isaias are affecting the coastlines of most of the eastern Gulf to SE Louisiana, and will increase along the Gulf coasts from SW Florida to Louisiana throughout the afternoon and evening. These swells are likely to cause large and powerful surf and life-threatening rip current conditions. Please consult products from your local weather office. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest Isaias NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...TROPICAL WAVES... An eastern Atlantic tropical wave is along 27W, south of 19N, moving westward at 5 to 10 kt. Scattered to locally numerous moderate isolated strong convection is observed from 05.5N to 16N and east of 29W to the coast of Africa. A western Caribbean tropical wave is along 79W-80W, south of 20N, moving westward at 10 kt. This wave continues to interact with an upper-level low over the NW Caribbean, and is producing scattered moderate isolated strong convection from 13.5N to 22N and between 76.5W and 81.5W. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic through the coast of Mauritania near 14.5N17W and continues southwestward to 09N24W to 11.5N35W to 09N40W. ITCZ extends from 09N48W to 10N62W. Scattered moderate convection is noted from 07.5N to 14N between 30W and 40W, and from 090N to 11N between 50W and 62W. Scattered moderate to strong convection is noted from 11N to 14.5N between 44.5W and 48W. ...GULF OF AMERICA... Please read the Special Features section above for more information on Major Hurricane Isaias centered over the northeast Gulf of America. Tropical storm force winds have moved to near or along the Gulf coast from Apalachicola, FL to SE Louisiana late this morning, with seas now 8 to 15 ft and rising across those waters. A 30 to 60 nm wide rainband extends from the eastern periphery of Isaias near 29N84W south-southwestward through the Yucatan Channel. Fresh to strong cyclonic winds spiral into Isaias from the Yucatan Channel northward between the western Florida coastal waters and the central Louisiana coastal waters near 93W. Elsewhere, a dissipating stationary front extends across N Florida and into the NE Gulf along 29N. Moderate to fresh cyclonic N to W winds prevail across the W and SW Gulf, where seas are 4 to 8 ft in NE to E swell from Isaias. Scattered showers are across the central Bay of Campeche. For the forecast, Isaias will move to near 29.7N 86.8W this evening, then move inland and weaken to a tropical storm near 32.1N 87.1W Sat morning with maximum sustained winds 55 kt, then weaken to a tropical depression well inland by Sun morning. Swell generated by Isaias will spread northward across the basin central Gulf through Sat night. In the wake of Isaias, weak high pressure will develop over the north- central Gulf by Sun evening resulting in moderate or weaker return flow over the western Gulf through midweek. ...CARIBBEAN SEA... Please read the Tropical Waves section for details on an active tropical wave in the western Caribbean. Weak 1019 mb high pressure has shifted southward into the western Atlantic near 26N62W, to the south of a cold front now along about 30N. The associated pressure gradient is sustaining moderate to fresh easterly winds and moderate seas to 6 ft across the basin between the tropical wave along 79W-80W and 63W. Moderate to fresh southerly winds and moderate seas are noted west of 84W through the Yucatan Channel, blowing into the general circulation of Hurricane Isaias. Light to gentle winds and seas of 2-4 ft are prevalent elsewhere. For the forecast, a weak pressure gradient is expected to continue across the basin through the next few days. Winds will pulse to strong speeds and seas will reach 8 ft tonight through Sun night in the south- central Caribbean and Gulf of Venezuela. Hurricane Isaias over the central Gulf of America is producing fresh southerly winds in the Yucatan Channel and these winds will lift northward later today. Meanwhile, a tropical wave near 80W, in combination with an upper- level low, is producing scattered showers and thunderstorms N of 16N between 76W and 82W. Unsettled weather conditions will remain associated with this wave as it moves across the western Caribbean through the weekend. ...ATLANTIC OCEAN... A cold front has drifted southward into the northern waters, extending from the central Atlantic through 31N60W to 29N64W, then meanders westward along about 30N into NE Florida. A weak 1019 mb high has developed south of this front near 26N62W. Fresh to strong NE winds and seas of 5-7 ft are found north of the front off NE Florida and GA. South of the front, a weak pressure gradient prevails west of 50W, supporting moderate or weaker winds and seas of 3-6 ft. An upper-level trough continues across the central Atlantic, extending S-SW across the area waters between 45W and 55W, and continues to produce scattered showers to the E between 40W and 52W. A surface trough along about 52W is drifting westward. A strong 1034 mb high pressure system is just north of the Azores and the surface trough along 52W combine to support moderate to fresh easterly winds and seas of 4-8 ft north of the monsoon trough and east of 46W. For the forecast west of 55W, the stationary front along about 30N and W of 64W will lift N as a warm front tonight into Sat. Fresh to strong E winds and rough seas are expected today off NE Florida as Hurricane Isaias tracks northward across the Gulf of America. These winds will veer to the SE at moderate to fresh speeds early on Sat before weakening to gentle to moderate speeds by Sun. Otherwise, as high pressure moves across the western Atlantic, a tightening pressure gradient will support NE to E winds of fresh to locally strong speeds and rough seas behind a cold front over the eastern waters, mainly N of 26N, Sun into Mon. Looking ahead, a new cold front is forecast to push off the U.S. southeastern coast early on Mon and move across the waters N of 29N through Tue night while it weakens. Light to gentle winds and moderate seas will dominate much of the basin early next week.