000 AXNT20 KNHC 131030 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Fri Oct 13 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 0600 UTC surface analysis and satellite imagery through 1015 UTC. ...SPECIAL FEATURES... Tropical Storm Sean is centered near 14.3N 40.5W at 13/0900 UTC or 960 nm W of the Cabo Verde Islands, moving WNW at 11 kt. Estimated minimum central pressure is 1004 mb. Maximum sustained wind speed is 40 kt with gusts to 50 kt. Scattered moderate to isolated strong convection is noted from 13N to 17N between 36W and 41W. Peak seas are around 15 ft, with the 12 ft seas extending outward 120 nm in the NE quadrant, 90 nm in the SE quadrant, and 75 nm in the NW quadrant. A turn toward the northwest with a slight decrease in forward speed is expected during the next few days. Gradual weakening is expected during the next few days, and Sean is forecast to degenerate to a post- tropical remnant low later this weekend. Please read the latest High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. West Atlantic Gale Warning: A gale force 997 mb low pressure is centered just N of the area near 32N69W. A cold front extends SW from the low to 30N81W. A warm front extends SE from the low to 26N55W. Gale force winds are noted ahead of the cold front mainly N of 29N and W of 67W. Seas in the area are likely 8 to 12 ft. The low and cold front will move eastward, spreading gale winds across the Atlantic waters N of 27N through the weekend. Seas of 12 to 18 ft are expected within the gale force wind area, peaking by this afternoon through Sat night north of 27.5N between 40W and 62W. 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... An eastern Atlantic tropical wave has an axis along 26W from 17N southward, moving W at 10 kt. A 1010 mb low pres (AL94) is along the wave near 09N26W. Scattered moderate to isolated strong convection is noted along the southern half of the wave axis from 02N to 11N between 25W to 30W. Environmental conditions are expected to become more conducive for development of this system by early next week. A tropical depression could form by the middle of next week while it moves westward or west-northwestward at about 10 kt across the eastern and central tropical Atlantic. This system has a low chance of development within the next 48 hours and a medium chance within the next 7 days. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal plains of Senegal near 15N18W to AL94 to 10N31W. Scattered moderate convection is noted S of the trough and E of 23W. ...GULF OF MEXICO... A 1007 mb low over the Florida Panhandle and associated stationary front extending to 26N87W. A surface trough continues from 25N88W to 22N95W. Scattered showers and thunderstorms are noted in the SE Gulf. Recent ASCAT satellite data shows winds are moderate or weaker across most of the basin. Seas are 3-4 ft in the western Gulf and 4-7 ft in the eastern Gulf. For the forecast, the low and associated stationary front will continue weakening today. Scattered showers and thunderstorms in the SE Gulf will also move E of the area today also. High pressure across the Atlantic will build modestly westward into the eastern Gulf through early Sat, before the next cold front moves into the NW Gulf Sat morning and across the entire basin by Sun evening. ...CARIBBEAN SEA... Mid to upper level ridging over the Caribbean is bringing fairly benign conditions over the area, with little to no precipitation currently noted across the basin. Recent ASCAT data shows that winds are mostly moderate across the basin, except for fresh in the south-central Caribbean. Fresh to strong SE winds are likely occurring in the Gulf of Honduras. Seas are 2 to 5 ft east of 82W, except 4 to 6 ft in the south-central Caribbean. Seas are likely 5 to 7 ft in the Gulf of Honduras. For the forecast, moderate to fresh trade winds across the eastern and central Caribbean will diminish to gentle to moderate today and prevail through Tue. Fresh to strong SE to S winds in the Gulf of Honduras will continue through tonight. A cold front will sink S-SE across the western Atlantic over the weekend maintaining the weak trade wind flow across the basin and support moderate to fresh northerly winds in the NW Caribbean Mon and Tue. ...ATLANTIC OCEAN... Please read the Special Features section for details on the Gale Warning over the western Atlantic and T.S. Sean. Please read the Tropical Waves section for details on AL94. Scattered moderate isolated strong convection is occurring south of the gale-frontal system/low in the western Atlantic, north of 26N and west of 60W. To the east, a cold front extends from 31N38W to 27N46W. Scattered moderate convection prevails within 250 nm S of the front. A surface ridge extends from 1014 mb high pressure near 25N31W. Gentle winds with little to no precipitation is near the surface ridge. Areas of fresh to strong winds and seas over 8 ft include Tropical Storm Sean, as well as the area in the western Atlantic north of 27N between 64W and 76W. Moderate to fresh winds and 5 to 7 ft seas prevail north of 24N between 30W and 50W. Gentle to moderate winds prevail elsewhere across the basin. For the forecast W of 55W, see the Special Features section above. $$ ERA