000 AXNT20 KNHC 171756 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Tue Oct 17 2023 Tropical Weather Discussion for North America, Central America Gulf of Mexico, 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 1745 UTC. ...SPECIAL FEATURES... Central Tropical Atlantic (AL94): A 1010 mb low pressure is located near 10.9N42.3W. Numerous moderate to isolated strong convection is evident from 05N to 15N and between 39.5W and 49W. Strong to near gale easterly winds are found northeast of the system, especially from 11.5N and 15N and between 37W and 45W. While, fresh to strong easterly winds are found north of the system, especially from 9.5N and 20N and between 39W and 43W. Furthermore, a Gale Warning will be in effect starting at 18/12Z. Environmental conditions are expected to remain conducive for gradual development, and a tropical depression will likely form during the next day or two while the system moves westward to west- northwestward across the central and western tropical Atlantic. Interests in the Lesser Antilles should monitor the progress of this system. This disturbance has a high chance of tropical cyclone formation through the next 48 hours. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. Additional information, regarding the Gale Warning, can be found in High Seas Forecasts issued by the National Weather Service. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic through the coast of Mauritania near 17.5N16W and continues southwestward to 06N27W to AL94 near 10.9N42.3W to 08N52W. Other than the convection associated with AL94 described in the Special Features section above, scattered moderate convection is observed from 01N to 07N and between 12W and 31.5W. ...GULF OF MEXICO... The Gulf of Mexico remains under the influence of a 1022 mb high pressure system extending from the U.S. Great Plains southward to Heroica Veracruz, Mexico, allowing for a dry continental airmass to dominate the basin. Moderate to fresh northerly winds are still occurring over most of the basin, except gentle to moderate winds over the NW Gulf. Additionally, locally strong NW winds are likely still occurring near Veracruz, with seas around 8 ft offshore Veracruz. Elsewhere south of 26N, seas are 5 to 9 ft. Seas are 4 to 6 ft over the NE Gulf and 2 to 5 ft in the NW Gulf. For the forecast, high pressure dominates the Gulf waters. Fresh N winds across the Gulf will gradually diminish today from north to south. Seas will gradually subside tonight into Wed as high pressure continues to build over the region. A frontal system will bring moderate to fresh winds for the NE Gulf on Fri. ...CARIBBEAN SEA... A stationary front extends from eastern Cuba to the Gulf of Honduras. Satellite imagery continues to depicts scattered showers and thunderstorms near the frontal boundary in the southern Gulf of Honduras, off the coast of Nicaragua, and between Jamaica and eastern Cuba. Scattered showers and thunderstorms are also seen from 12N to 15.5N between 73W and 76W in association to deep layer trough. To the northwest of the stationary front, moderate to fresh north winds are occurring, along with seas 5 to 7 ft. Moderate to locally fresh easterly trade winds are evident in the south- central and southeast Caribbean, along with seas of 3 to 5 ft. Elsewhere, light to gentle winds and slight seas prevail. For the forecast, the aforementioned stationary front should remain in place through Wed before dissipating Wed night. Fresh NE winds and moderate seas will persist over the northwest Caribbean through Wed as high pressure builds over the area. Looking ahead, a broad area of low pressure located over the central tropical Atlantic about 1100 miles east of the Windward Islands has a high chance of tropical cyclone formation trough 48 hours with a high chance of formation beyond 48 hours. This system is forecast to approach the waters E of the Leeward Islands Fri into Sat bringing increasing winds and seas. ...ATLANTIC OCEAN... Please see the SPECIAL FEATURES section above for more details on Invest 94L. A stationary front extends from 31N64W to eastern Cuba. A clusters of scattered thunderstorms are noted along and within 120 nm SE of the front over the SE Bahamas. Elsewhere, along the front isolated to scattered thunderstorms are depicted. Moderate to fresh winds and seas 6 to 9 ft are occurring from 25N to 31N between 55W and 81W. Winds are mainly gentle farther south, to the north of eastern Cuba, Hispaniola and Puerto Rico. Farther east, a surface trough is associated with the remnants of Sean and are producing scattered showers and isolated thunderstorms from 16N to 23N between 53W and 60W. A surface ridge extends from 30N31W to 1021 mb high pressure near 27N42.5W to 26N47W to 23N61W. Light to gentle winds and 5 to 7 ft seas are near the ridge axis. In the far NE part of the area, north of 29N and east of 29W, large swell of 7 to 9 ft is subsiding, due to a departing storm system far to the north. For the forecast W of 55W, the aforementioned stationary front will remain in place before dissipating Wed night or Thu. Expect fresh winds over waters north of 25N through this morning, on both sides of the front. Winds and seas will diminish tonight as high pressure builds over the area in the wake of the front. Looking ahead, the next frontal system will move offshore the southeastern United States Fri night. Fresh to strong winds and rough seas are forecast north of 27N Fri night through Sat night with this system. A broad area of low pressure located over the central tropical Atlantic about 1100 miles east of the Windward Islands has a medium chance of tropical cyclone formation trough 48 hours and a high chance of formation beyond 48 hours. This system is likely to be near the northern Leeward Islands by Sat, bringing increasing winds and seas. $$ KRV