


Tropical Weather Discussion
Issued by NWS
Issued by NWS
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268 AXNT20 KNHC 040547 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0615 UTC Sat Oct 4 2025 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 0000 UTC surface analysis and satellite imagery through 0547 UTC. ...SPECIAL FEATURES... Significant Swell Event over the Western and Central Atlantic: Large northerly swell generated by hurricane force winds associated with previous Tropical Cyclones Imelda and Humberto in the northern Atlantic are propagating across the forecast waters S of 31N building seas to 16 to 18 ft over the central Atlantic. Seas 12 ft or greater dominate a large area, particularly N of 23N between 43W and 73W. Altimeter data and buoy observations confirmed the presence of these sea heights. This swell event will continue to expand southward this weekend, leading to widespread rough seas north of 10N. Very rough seas in excess of 12 ft are expected north of 23N this weekend, including near the northern Bahamas. In addition, this swell event will also sustain dangerous surf conditions, significant beach erosion and probable local coastal inundation along the east- facing shores of Georgia and Florida, the north and east-facing shores of the Bahamas, and the north- facing shores across Hispaniola, Puerto Rico, the Virgin and Leeward Islands. Refer to your local weather agencies for the latest statements. Please read the latest NWS High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for further details. ...TROPICAL WAVES... A tropical wave emerged yesterday afternoon off the coast of Africa. Its axis is along 18W. A cluster of moderate to isolated strong convection is depicted from 11N to 14N and east of 19W. Scattered moderate convection is found from 06N to 08N between 16W and 18.5W. The wave is forecast to interact with another disturbance over the eastern tropical Atlantic, and then move westward after that. Environmental conditions are expected to become conducive for some slow development of the system in a few days, and a tropical depression could form near or east of the Lesser Antilles by the end of next week. There is a medium chance of tropical development within the next 7 days. A central Atlantic tropical wave is near 40W from 20N southward. It is moving west at around 10 kt. Dryness at low to mid levels are prohibiting significant convection near this wave. Another tropical wave is east of the Lesser Antilles near 54.5W from 20N southward, and moving west around 5 kt. Scattered showers and isolated thunderstorms are noted E of the wave axis from 13N to 17N between 47W and 52W. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic Ocean near 13N17W, then continues southwestward to 06N26W and northwestward to 13N45W. Numerous moderate to isolated strong convection is present from 02N to 13N between 18W and 30.5W. ...GULF OF AMERICA... An old frontal boundary is producing scattered moderate convection north of 26N between 83W and 91W. A surface trough over the Bay of Campeche is supporting numerous showers, with embedded thunderstorms, across the central and eastern Bay of Campeche, and north of the Yucatan Peninsula. Fresh to strong NE to E winds, and moderate seas dominate the NE and N Gulf due to the pressure gradient between high pressure over the eastern United States and an old frontal boundary meandering across the Bahamas, south Florida, and across the eastern Gulf. Fresh N winds and seas of 4 to 6 ft are occurring near and offshore of Veracruz, Mexico. Gentle to moderate NE to E winds and slight to moderate seas prevail elsewhere. For the forecast, fresh to strong NE to E winds and locally rough seas will prevail over the northern Gulf, mainly north of 26N, tonight into early Sun, as a strong pressure gradient prevails between high pressure across the eastern U.S. and an old frontal boundary meandering across the Bahamas, south Florida, and across the eastern Gulf. This boundary will begin to lift northward as a warm front in the central Gulf early Sun and into the southeastern United States Mon, supporting slowly diminishing winds over the northern basin. Moderate E to SE winds and slight to moderate seas are expected over the rest of the Gulf into next week. ...CARIBBEAN SEA... A weak pressure gradient dominates the Caribbean Sea supporting moderate to locally fresh trades across the south-central Caribbean, and light to gentle winds elsewhere. Slight seas prevail across the basin, except for higher seas of 6 to 7 ft in N swell across the NE Atlantic passages, including the Mona and Anegada Passes. An upper-level low is spinning over Hispaniola, with an upper- level trough extending to eastern Panama. These features are enhancing convection over most of the western half of the basin, including Hispaniola, Jamaica and eastern Cuba as well as parts of the south-central Caribbean and central America. For the forecast, gentle to moderate trade winds will prevail over most of the Caribbean Sea into next week as a weak pressure gradient persists across the region. Large N to NE swell, generated by previous Tropical Cyclones Imelda and Humberto, will continue to produce rough seas in the Atlantic Passages and over the waters E of the Lesser Antilles into early next week. Seas will slowly subside early next week. Looking ahead, moderate to occasionally fresh E to SE winds will pulse in the Gulf of Honduras Sat night into early next week. ...ATLANTIC OCEAN... Please read the Special Features section at the very beginning about large northerly swell. The pressure gradient between high pressure over the eastern United States and an old frontal boundary and weak area of low pressure near the Bahamas is supporting fresh to strong NE to E winds off the coast of Florida and over the northern Bahamas, generally north of 25N and west of 70W. Farther east, a cold front enters the forecast area near 31N47W, then continues SW to near 23N61W where it becomes a stationary front that extends to a 1011 mb low pressure located over the central Bahamas. In addition, a pre frontal trough is analyzed from 31N44W to 24N56W. Scattered showers and thunderstorms are near the front and the pre frontal trough, more concentrated near the stationary front. Fresh to strong SW winds are N of 29N and E of the front to about 41.5W. North of the front, moderate to fresh winds prevail. Very rough seas, in northerly swell, follow the front. An upper-level trough is generating some convective activity north of 26N between 22W and 29W. Gentle to moderate winds are observed over the tropical Atlantic. For the forecast west of 55W, fresh to strong NE winds will continue off the coast of Florida and over the northern Bahamas, generally north of 25N and west of 70W, tonight into early next week, as an old frontal boundary and weak area of low pressure meanders across the NW Bahamas and south Florida over the next several days. Farther east, fresh NE to E winds are expected north of a cold front extending from 26N55W to 23N66W to the NW Bahamas into Sun. The front will lift northward and weaken this weekend. Large N to NE swell generated by previous Tropical Cyclones Imelda and Humberto will continue to propagate southward this weekend, leading to widespread rough seas north of 10N. Seas in excess of 12 ft are expected north of 23N this weekend, including near the northern Bahamas. Looking ahead, a tropical wave has just emerged off the coast of Africa. The wave is forecast to interact with another disturbance over the eastern tropical Atlantic, and then move westward after that. Environmental conditions are expected to become conducive for some slow development of the system in a few days, and a tropical depression could form near or east of the Lesser Antilles by the end of next week. $$ KRV