000 AXNT20 KNHC 051548 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Wed Oct 5 2022 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 1545 UTC. ...SPECIAL FEATURES... Tropical Depression Twelve... As of 05/1500 UTC, Tropical Depression Twelve is centered near 15.6N 32.0W or about 460 nm west of the Cabo Verde Islands. It is moving WNW at 8 kt, with an estimated minimum central pressure of 1007 mb. Maximum sustained winds are 30 kt with gusts to 40 kt. Combined seas are in the 8-11 ft range near and north of the center. Satellite imagery shows that the depression is losing organization and now has an exposed low-level center displaced from the associated deep convection due to strong WSW shear. The current forecast indicates that the depression will become a remnant low in the next 24 hours. Please read the latest High Seas Forecast issued by Meteo-France at website http://weather.gmdss.org/ll.html and the latest NHC Forecast/Advisory and Public Advisory at www.nhc.noaa.gov/text/MIATCMAT2.shtml and www.nhc.noaa.gov/text/MIATCPAT2.shtml for more details. Tropical Wave/Broad Low Pressure... A tropical wave crossed the Windward Islands this morning and is now in the far eastern Caribbean along 62W from the coast of Venezuela to 17N. A 1007 mb low pressure center is analyzed along the wave near the southern Windward Islands at 11.5N 61.7W. Fresh to strong easterly winds are observed north of the low, with seas to 9 ft. This system is moving westward around 15 kt. While the system has not become any better organized since yesterday, upper- level winds are forecast to become more conductive for development, and a tropical depression is likely to form over the next several days if the system remains over water. Regardless of development, 2-4" of rainfall and strong winds are expected to impact the southern Windward Islands today before moving to the northern coast of South America and southern Caribbean Islands over the next few days. There is a medium chance of tropical cyclone development over the next 48 hours and a high chance through 5 days. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Senegal near 14N17W to 12N24W, where the convergent flow is interrupted by Tropical Depression Twelve. The monsoon trough continues southwest of TD12 from 13N33W to 08N72W. The ITCZ continues from 08N72W to 05N53W along the coast of French Guiana. Scattered moderate convection is observed from 08N to 12N, between 34W and 43W. The eastern segment of the East Pacific monsoon trough extends across the SW Caribbean and is triggering scattered moderate with isolated strong convection within 120 nm from the coast of Costa Rica, Panama and NW Colombia. ...GULF OF MEXICO... Overall, the Gulf of Mexico is under the influence of weak high pressure and favorable marine conditions. A NW-SE oriented surface trough extends from near Houston to the central Gulf of Mexico. NE of this trough, winds are gentle to moderate from the E with 2-3 ft seas. SW of the trough, winds are light to gentle from the NE with 1-2 ft seas. A cold front extends through the Florida Straits, with scattered weak showers along portions of the boundary. For the forecast, the tail end of a cold front extends across the Florida Straits along 24N and E of 86W with scattered showers. The front will drift south through the end of the week, then stall and dissipate by late Sat. High pressure north of the area will maintain gentle to moderate easterly winds and slight to moderate seas through Thu. Another cold front is expected to move into the northern Gulf Fri, the central Gulf Sat and the southeastern Gulf and Straits of Florida Sun and Sun night, then stall. Expect fresh northeast to east winds across the southeastern Gulf starting Fri and through Sun night as the pressure gradient tightens between high pressure north of the fronts and lower pressure in the western Caribbean. ...CARIBBEAN SEA... Please read the Special Features section for more details on the tropical wave and associated broad low pressure area located near the southern Windward Islands. Outside of impacts from the tropical wave, the gradient between subtropical high pressure and lower pressure over South America is supporting moderate easterly winds in the central and eastern Caribbean, with 3-5 ft seas. The gradient relaxes in the western Caribbean with gentle winds and 2-4 ft seas. For the forecast, a broad area of low pressure located near the southern Windward Islands continues to produce a large area of disorganized showers and thunderstorms. Regardless of development, heavy rainfall with localized flooding, as well as gusty winds to gale force, are expected over portions of the Windward Islands, northern portions of South America, and the ABC Islands during the next couple of days. Interests in those locations, in addition to those in Central America, should continue to monitor the progress of this system. Elsewhere, gentle to moderate northeast winds slight to moderate seas are expected across the basin through late Fri, except for winds increasing to moderate to fresh over most of the western Caribbean Fri through Sun night as the pressure gradient tightens between the low pressure area and strong high pressure north of the Caribbean. ...ATLANTIC OCEAN... Please read the Special Features section for details on Tropical Depression Twelve in the eastern Atlantic Basin. A mostly dry cold front is analyzed from 31N67W, across the northern Bahamas to the Florida Straits. Behind the front winds are moderate from the north with 5-7 ft seas, some of which is swell from a mid-Atlantic storm. Ahead of the front, winds are gentle from the W with 5-7 ft seas. East of 65W, winds are moderate from the S with 5-7 ft seas. In the central Atlantic, high pressure north of the area is the dominate feature with moderate easterly winds and 4-6 ft seas. A tighter pressure gradient in the eastern Atlantic is causing fresh to strong NE winds and 6-8 ft seas. For the forecast west of 55W, a cold front that extends from near 31N68W to 24N79W will stall from near Bermuda to the southern Bahamas and the Straits of Florida Fri. The front will dissipate by late Sat. Another cold front will sweep southeastward reaching from near Bermuda to the central Bahamas and to vicinity South Florida and the Straits of Florida Sun and also stall. Expect for northeast winds to increase to fresh speeds over the southwest part of the area and Straits of Florida starting late Thu as the gradient tightens between the fronts and strong high pressure to the north of them. Seas to 8 ft in northeast swell north of the Bahamas and east of northeast Florida will subside by this afternoon. $$ Flynn