


Tropical Weather Discussion
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Issued by NWS
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860 AXNT20 KNHC 041033 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1215 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 0600 UTC surface analysis and satellite imagery through 0940 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, creating seas of 16 to 18 ft over the central Atlantic N of 28N between 50W and 60W. Seas 12 ft or greater dominate a large area, particularly N of 23N between 42W and 75W, as recently verified by satellite altimeter data and buoy observations. This swell event will continue to spread southward this weekend, leading to widespread rough seas north of 12N. High 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, and 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 is offshore of the coast of Africa along 19W, moving west at 10 kt. A large cluster of moderate to strong convection is depicted from 11N to 14.5N and east of 21.5W. Scattered moderate convection is found elsewhere from 02.5N to 14.5N between 18W and 28W. The wave is forecast to interact with another disturbance over the eastern tropical Atlantic, and then continue to 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 41W from 20N southward. It is moving west at around 10 kt. Dry and relatively stable conditions at low to mid levels are prohibiting significant convection near this wave. Another tropical wave is east of the Lesser Antilles near 55W from 20N southward, and moving west around 5 kt. Scattered showers and isolated thunderstorms are noted E of the wave axis from 12.5N to 18N between 47.5W and 54W. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic Ocean near 14N17W and continues south-southwestward to 09N21W then northwestward to 14N50W. Scattered moderate isolated strong convection is present from 02.5N to 13N between 22W and 47.5W. ...GULF OF AMERICA... An old frontal boundary extends from near Andros Island, Bahamas through the Straits of Florida to near 27N91W in the north-central Gulf. High pressure across the middle Atlantic states extends a ridge southward into the northeast Gulf, and is producing fresh to strong NE to E winds north of the frontal boundary and E of 94W. Seas across this area are 5 to 8 ft. Low level convergence along this boundary is producing scattered moderate convection along and within 120 nm north of it between 82W and 91W. A surface trough over the Bay of Campeche is supporting scattered showers and isolated thunderstorms across the central and eastern Bay of Campeche, and north of the Yucatan Peninsula. Fresh N winds and seas of 4 to 6 ft are occurring near 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, into early Sun, as a tight 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 into the central Gulf early Sun and then inland across 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 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 9 ft as large N swell moves through the NE Caribbean passages, including the Mona and Anegada Passes. An upper-level low is spinning over Hispaniola and the Mona Passage, with an associated upper-level trough extending to eastern Panama. These features are enhancing convection over most of the western half of the basin, including scattered moderate to strong convection S of 16N between the coasts of Colombia and Nicaragua. 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 Atlantic waters E of the Lesser Antilles into Sun night. Seas will slowly subside early next week. Looking ahead, moderate to occasionally fresh E to SE winds will pulse in the Gulf of Honduras Sun night into early next week. Looking ahead, a tropical wave is offshore of Africa and inducing active convection there. The wave is forecast to interact with another disturbance over the eastern tropical Atlantic, and then continue to 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. ...ATLANTIC OCEAN... Please read the Special Features section about the large northerly swell event currently dominating Atlantic seas. The pressure gradient between high pressure over the eastern United States and an old frontal boundary and weak area of low pressure across the central Bahamas is supporting fresh to strong NE to E winds off the coast of Florida north of Miami, and over the northern Bahamas, generally north of 25N and west of 70W. Seas are 8 to 13 ft in NE swell across this area. Farther east, a cold front enters the forecast area near 31N45W, then continues SW to near 22N64W where it becomes a stationary front that extends to a 1011 mb low pressure located over the central Bahamas near 24N77.5W. Fresh to locally strong NE to E winds generally prevail north of the cold front to 70W. Scattered showers and thunderstorms are near the front, more concentrated near the stationary portion of front. Fresh to strong SW winds are N of 29N and E of the front to about 41.5W. Very rough seas, in northerly swell, follow the front, with seas 12 ft and higher N of 23N between 42W and 75W. Peak seas along 31N between 50W and 60W are 18 ft. Gentle to moderate trade winds are observed over the tropical Atlantic between 30W and the Lesser Antilles. Seas there are 6 to 9 ft in building NW to N swell. 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, 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 to strong NE to E winds are expected through Tue north of a cold front extending from 26N55W to 24N70W to the NW Bahamas. 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 12N. Seas in excess of 12 ft are expected north of 23N this weekend, including near the northern Bahamas through this morning. Looking ahead, a tropical wave has 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 this system in a few days, and a tropical depression could form near or east of the Lesser Antilles by the end of next week. $$ Stripling