711 AXNT20 KNHC 162110 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 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 1800 UTC surface analysis and satellite imagery through 1815 UTC. ...SPECIAL FEATURES... Central Tropical Atlantic (AL94): A broad area of 1012 mb low pressure located over the central tropical Atlantic near 10N39W, about midway between the Windward Islands and western Africa is producing a large area of disorganized showers and thunderstorms. Numerous moderate isolated strong convection is evident from 05N to 12N between 34W and 44W. Winds are currently 20-25 kt with seas of 8 ft at most. Satellite data indicate that the low-level circulation continues to become better defined and, since environmental conditions are expected to remain conducive for further development, a tropical depression is likely to form within a few days. This system is forecast to move westward to west-northwestward across the central and western tropical Atlantic during the next several days. This system has a medium chance of tropical cyclone formation through the next 48 hours, and a high chance of tropical cyclone formation through the next 7 days. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave is in the Atlantic Ocean along 32W, from 18N southward, moving W at around 10 kt. No significant deep convection is present with this tropical wave. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the border of Guinea-Bissau and Guinea near 11N15W to 08N30W to low pressure (AL94) near 10N39W to 08N44W. The ITCZ extends from 08N44W to 08N58W. Other than the convection associated with AL94 described in the SPECIAL FEATURES section above, scattered moderate isolated strong convection is evident from 02N to 08N between 18W and 26W, and from 08N to 12.5N between 44W and 59W. ...GULF OF MEXICO... High pressure located over the central United States dominates the basin in the wake of the first strong cold front of the season. Fresh to strong NW-N winds prevail across the entire Gulf as sampled by an earlier ASCAT scatterometer pass. Seas are 7-10 ft, except 3-6 ft in the northern Gulf coastal waters. For the forecast, high pressure dominates the Gulf waters. Fresh to strong N winds will continue across most of the Gulf of Mexico through tonight before gradually diminishing Tue. Seas will gradually subside into mid week as high pressure continues to build over the region in the wake of a cold front now located SE of the area. ...CARIBBEAN SEA... The first strong cold front of the season is in the NW Caribbean, extending from central Cuba to near the Gulf of Honduras. Fresh to locally strong NW-N winds are filtering in behind the front including through the Yucatan Channel. Seas of 4-7 ft are also building behind the front, highest near the Yucatan Channel. Scattered showers and isolated thunderstorms are present within 75 nm along and ahead of the front, with similar activity in the Gulf of Honduras. Scattered moderate isolated strong convection is found in the SW and S-central Caribbean due to the proximity of the eastern Pacific monsoon trough which extends along 11N/12N. Otherwise, fair weather is found in the Caribbean. Winds are mainly light to gentle SE of the cold front, locally moderate offshore Venezuela including across the A-B-C Islands. Seas are mainly 3 ft or less SE of the cold front. For the forecast, the front will reach from eastern Cuba to the Gulf of Honduras by Tue morning before stalling, and then gradually dissipating into mid-week. 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 midway between the Windward Islands and western Africa has now a medium chance of tropical cyclone formation trough 48 hours. This system is forecast to approach the waters E of the Leeward Islands late Fri into Sat bringing increasing winds and seas. ...ATLANTIC OCEAN... Please see the SPECIAL FEATURES section above for more details on a broad area of 1012 mb low pressure (AL94) located over the central tropical Atlantic about midway between the Windward Islands and western Africa near 10N39W. A strong cold front extends from SE of Bermuda through 31N65W to the SE Bahamas, with another front and frontal trough 120-300 nm ahead of it N of 22N. Scattered showers and thunderstorms are N of 24N between the two boundaries. Fresh to locally strong winds follow the parent front, with fresh SW winds ahead of it. Seas are mainly 5-8 ft W of the leading front/frontal trough. Low pressure, the remnants of Sean, is near 18N52W with associated winds of moderate to fresh and seas of 6-7 ft. A ridge of high pressure extending from near the Canary Islands through 27N38W to along 22N dominates the remainder of the waters. Gentle to moderate winds are found under the ridge. Seas are mainly 4-7 ft across the open waters, except 7-10 ft N of 29N between the Canary Islands and 35W associated with a low pressure system well N of the area. For the forecast W of 55W, the strong cold front will reach from 31N63W to eastern Cuba by Tue morning, then stall on Wed before dissipating on Thu. Expect fresh to locally strong winds over waters north of 25N through tonight, on both sides of the front. Winds and seas will diminish into mid week as high pressure builds over the area in the wake of the front. Looking ahead, a broad area of low pressure located over the central tropical Atlantic about midway between the Windward Islands and western Africa has now a medium chance of tropical cyclone formation trough 48 hours. This system is forecast to approach the waters E of the Leeward Islands late Fri into Sat bringing increasing winds and seas. $$ Lewitsky