


Tropical Weather Discussion
Issued by NWS
Issued by NWS
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155 AXNT20 KNHC 171800 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1815 UTC Fri Oct 17 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 1200 UTC surface analysis and satellite imagery through 1800 UTC. ...SPECIAL FEATURES... Atlantic Large Swell Event: Northerly swell generated from a storm force low over the Atlantic waters north of the discussion area will support rough to very rough seas over the western Atlantic through this weekend. Very rough seas in excess of 12 ft will propagate into the discussion waters between 60W and 70W beginning today. The area of 12 ft and greater seas will spread southeastward on Sat, covering the waters north of 27N between 43W and 70W by Sat night. The swell will then start to subside over the discussion waters allowing for seas to drop below 12 ft Sun night. Seas with this swell will peak near 18 ft over the waters north of about 30N between 50W and 65W on Sat. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details. ...TROPICAL WAVES... The axis of a central Atlantic tropical wave is near 41W from 16N southward, moving westward at around 15 kt. Scattered moderate to isolated strong convection is noted from 05N to 12N between 38W and 45W. Some gradual development of this system is possible over the next several days as it continues westward. Gradual development of this system is possible over the next several days while it moves generally westward at 15 to 20 kt. Regardless of development, this system is expected to bring heavy rainfall and gusty winds to the Windward Islands late this weekend and then move across the Caribbean Sea much of next week. This wave has a low chance of tropical cyclone formation in the next 48 hours. The axis of a central Atlantic tropical wave is near 52W from 16N southward. It is moving westward near 15 kt. Scattered moderate to isolated strong convection is noted from 06N to 13.5N between 48W and 58W. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic near 11N16W and extends southwestward to near 04N35W. Aside from convection noted in the tropical waves section, scattered moderate to isolated strong convection is noted from 00N to 08N between 15W and 36W. ...GULF OF AMERICA... A surface trough is supporting isolated moderate convection over the central part of the basin. Gentle to moderate E to SE winds prevail east of 94W with seas 3 to 5 ft. West of 94W, light winds and seas 2 to 3 ft prevail. For the forecast, moderate E to SE winds and slight to moderate seas are expected over much of the Gulf through late Sat as high pressure prevails over the southeastern United States. Occasionally fresh E winds will be possible in the central and eastern basin. A cold front is slated to enter the northwestern Gulf on Sun and progress southeastward through the basin into early next week, and moderate to locally fresh N to NE winds are expected in the wake of the front Sun into Mon. Generally moderate NE to SE winds and slight to moderate seas will return over the Gulf early next week as weak ridging builds over the region. ...CARIBBEAN SEA... A frontal trough extends from NW Haiti, to the Yucatan Passage. Satellite imagery shows clusters of scattered showers and thunderstorms along and near this boundary. A weak pressure gradient is across the Caribbean waters supporting gentle to moderate winds E of 65W, and light to gentle winds elsewhere. Seas are in the 3-5 ft range E of 64W, and 1-3 ft elsewhere. For the forecast, gentle to moderate winds and slight seas are expected over the Caribbean Sea through Sat. Moderate to fresh E to NE winds and moderate seas will develop over the eastern Caribbean Sat night and extend into the central basin on Sun as a tropical wave moves westward over the region. A second, stronger tropical wave is slated to move through the central Atlantic this weekend, entering the eastern Caribbean early next week. Fresh to strong winds and rough seas will accompany the wave as it passes over the waters east of the Leeward Islands on Sun, with increasing winds and building seas developing in the eastern basin Sun night into early next week. This system has a low chance of tropical development within the next 48 hours and next 7 days. Regardless of development, this system is expected to bring heavy rainfall and gusty winds to the Windward Islands late this weekend and then move across the Caribbean Sea much of next week. ...ATLANTIC OCEAN... Please refer to the Special Features section for further details on a large swell event that will begin to impact some sections of the north-central waters today. A cold front extends from 31N48W to 19N65W then becomes a trough to Hispaniola. Fresh to strong SW winds, and seas of 8-13 ft are N of 20N and E of the front to 40W. A reinforcing front extends from 31N56W to 25N68W then becomes stationary to the central Bahamas. Fresh to strong NW winds and seas of 8-12 ft are W of the front. Moderate to fresh winds, and seas of 8-9 ft are between the fronts. High pressure dominates the remainder of the discussion waters N of 20N, anchored by a 1018 mb high near 24N33W. Light to gentle winds are around the high center. Fresh to strong winds are in the vicinity of the tropical wave near 41W. Gentle to moderate winds prevail elsewhere. Seas are in the 5-7 ft range. For the forecast W of 55W, fresh to strong SW winds, with localized near-gale force winds, will occur over the central Atlantic north of 20N and east of 65W through Sat night as a cold front slowly migrates eastward. A second cold front, extending from 31N56.5W southwestward through the central Bahamas, will propagate eastward through this weekend, and fresh to strong N to NW winds will occur in the wake of the front north of 25N and east of 75W through Sun morning. Widespread rough seas associated with the first cold front will prevail north of 20N and east of 60W today, and will be reinforced by a new N to NW swell through this weekend, leading to rough seas north of 20N and east of 80W. Very rough seas over 12 ft can be expected north of 25N between 45W and 55W through Sat night. A second area of very rough seas will move into the forecast waters east 72W and north of 25N today, with seas in excess of 12 ft continuing through Sun. Rough seas will slowly subside from west to east Sun into next week. Elsewhere, a tropical wave is located over the central tropical Atlantic along 41W. Gradual development of this system is possible over the next several days while it moves generally westward. Regardless of development, this system will lead to increasing winds and building seas along its path. This system has a low chance of tropical development within the next 48 hours and next 7 days. $$ KRV