000 AXNT20 KNHC 051109 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Wed Oct 05 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 0600 UTC surface analysis and satellite imagery through 1100 UTC. ...SPECIAL FEATURES... Tropical Depression Twelve... As of 05/0900 UTC, Tropical Depression Twelve is centered near 15.8N 31.2W or about 420 nm west of the Cabo Verde Islands. It is moving NW at 7 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 a sheared system, with its center displaced to the southwest of the main area of related convection. This convection consists of numerous type intensity within about 240 nm of the center of the depression. The depression is forecast to maintain its current motion through Thu. Little change in strength is forecast and the system is expected to dissipate in a couple of days. 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.hurricanes.gov for more details. Tropical Wave/Broad Low Pressure... A tropical wave is approaching the Windward Islands, with axis along 60W and south of 17N to near the Guyana- Suriname border. Low pressure of 1007 mb is along the wave axis near 12N60W. This system is moving westward around 13 kt. Fresh to strong east to southeast winds along with seas of 8-10 ft are evident up to 270 nm north and east of the low center, including waters near Barbados. An overnight ASCAT pass captured these winds. Satellite imagery shows numerous moderate to scattered strong convection in clusters from the Venezuela- Guyana coast to 13N between 57W and 60W. Some of the surface observations from the Windward Islands indicated southeast winds gusting to gale force. For the chances of further development on this system, it is medium for the next 48 hours and high for the next 5 days. 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. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough axis enters the Atlantic Ocean along the African coast near the Senegal-Gambia border and continues west-northwestward to Tropical Depression Twelve, and from there southwestward to 10N37W and to 09N42W, where overnight scatterometer data indicates that it transitions to the ITCZ to 08N47W and to 12N56W. Besides convection associated with Tropical Depression Twelve, scattered moderate to isolated strong convection is within 60 nm north of the trough between 35W-39W, and scattered moderate convection is south of the trough from 09N to 12N between 28W-32W and also within 30 nm of the ITCZ between 52W-55W. The eastern segment of the East Pacific monsoon trough is triggering scattered to numerous moderate to strong convection in the extreme southwestern Caribbean south of 11n from the coastal section of Colombia to the waters along the coasts of southern Costa Rica and Panama. ...GULF OF MEXICO... A surface trough is analyzed south of Louisiana from near 29N92W to 25N91.5W. Isolated showers are near the trough. The trough is moving westward. A dry cold front extends from the the upper Florida Keys westward to near 25N88W. Otherwise, relatively weak high pressure is present over the area. Partial overnight ASCAT data passes depict gentle to moderate northeast to east winds along with seas of 2-3 ft over the eastern Gulf and Bay of Campeche. Mainly gentle northeast winds along with low seas of 1-2 ft remain over the rest of the Gulf. For the forecast, the aforementioned cold front will slowly move southward across the rest of the southeastern Gulf this morning, and continue to weaken as it reaches the Straits of Florida on Fri, where it will 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 east of the southern Windward Islands. A 1010 mb low is analyzed offshore the northern Nicaragua coast near 15.5N82W. A trough extends northeastward from the low to near 20N79W, and another trough extends from the low southeastward to near 12N81W. Scattered showers and thunderstorms are noted over the west central basin, including the Cayman Islands. Refer to the Monsoon Trough/ITCZ section for additional weather in the Caribbean Basin. Moderate to locally fresh easterly winds and seas of 5-7 ft are over the eastern basin. Gentle to moderate northeast to east winds and seas of 3-5 ft are over the central section of the sea. Light to gentle, with locally moderate northerly winds and seas of 2-4 ft continue over the western section of the sea. For the forecast, the broad low pressure mentioned in the Special Features section will move across the Caribbean through Sat night, possibly as a tropical cyclone. It will bring strong winds, some with possible brief gusts to gale force and rough seas to the Leeward and Windward Islands tonight, the eastern and central Caribbean through Fri, and the southwestern Caribbean through Sat night before moving into Central America. Interests across the region should monitor the progress of this system. Elsewhere, gentle to moderate NE winds with slight to moderate seas are expected 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 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, and the broad low pressure east of the Windward Islands. A mostly dry cold front is analyzed from a position of about 210 nm west of Bermuda, south-southwestward to 31N70W, to 27N73W and to the upper Florida Keys. Convergent southerly winds to the east are resulting in pockets of scattered moderate convection from 22N to 27N between 58W-69W A pronounced upper-level low near 26N34W is generating scattered moderate convection from 25N to 27N between 33W-35W, and farther east from the northern Cabo Verde Islands northeastward to the Canary Islands. The pressure gradient related to high pressure ridging near and north of 31N is channeling gentle to locally moderate northeast to east to southeast winds. Seas produced by these winds are 3-4 ft north of 21N between the northwest African coast and 65W. Farther west, moderate north to northeast winds and seas of 7-9 ft due to a north to northeast swell are present behind the aforementioned cold front, while mainly gentle south to southwest winds and seas of 5-7 ft are east of the front to 65W. Over the southern part of the area, outside the influence of the broad low pressure, gentle to locally moderate northeast to northeast to east winds and seas of 3-5 ft seas are evident from 10N to 21N between 34W and the Lesser Antilles. For the remainder of the Atlantic Basin outside the vicinity of the waters near Tropical Depression Twelve, light to gentle monsoonal and southerly winds with 5-7 ft seas in southerly swell are present. For the forecast west of 55W, the dry cold front will stall from near Bermuda to the central 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 9 ft in northeast swell north of the Bahamas and east of northeast Florida will subside by early this afternoon. $$ Aguirre