000 AXNT20 KNHC 232329 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Sat Jul 24 2021 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 2100 UTC. ...SPECIAL FEATURES... 1016 mb low pressure centered well east of Jacksonville, Florida, near 31N79W has a trough that extends S-SW to near Stuart, Florida. This low continues to produce a large region of disorganized showers and thunderstorms, currently within 60 nm east of Fort Pierce, Florida. Environmental conditions appear marginally conducive for additional development, and there is a medium chance a tropical depression could form over the next couple of days as the system meanders over the Gulf Stream, just offshore of the southeastern United States. Heavy Rainfall in Southern Central America: High moisture levels, persistent strong trade wind flow, and favorable conditions aloft will together support heavy rainfall for much of southern Central America through early next week. The heaviest rain is expected over the Caribbean coast of Costa Rica and southeast Nicaragua. These rains could cause significant flooding and mudslides in some areas. Currently, scattered moderate convection is noted along the Caribbean coast from northern Costa Rica through western Panama. ...TROPICAL WAVES... An Atlantic tropical wave is analyzed along 56W, from 04N to 19N, moving W 10 to 15 kt, approaching the Lesser Antilles. A few showers and thunderstorms are noted from 17N to 20N between the wave axis and the Leeward Islands. Patches of Saharan dust are following the tropical wave over the tropical Atlantic. A Caribbean tropical wave is analyzed along 70W, from the Dominican Republic to northwest Venezuela, moving W at 15 to 20 kt. No significant convection is associated with this wave. Another Caribbean tropical wave is analyzed along 82W, north of 14N through central Cuba. No significant convection is associated with this wave. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic Ocean near Guinea-Bissau near 12N16W to 08N25W to 10N40W. The ITCZ continues from 10N40W to 12N55W. Scattered moderate convection is noted over the eastern Atlantic from 09N to 11N between 18W and 20W, and also over the western Atlantic from 08N to 10N between 47W and 53W. GULF OF MEXICO... 1023 mb high pressure centered near 26N92W is the dominant features over the Gulf. Fresh NE winds may be funneling off the west coast of the Yucatan Peninsula, between the high pressure to the north and lower pressure farther south. A few showers and thunderstorms are also evident in this area, influenced by divergent flow aloft on the southeast side of an upper low parked over 20N93W in the Bay of Campeche. Moderate to locally fresh S winds are noted along the Texas coast, west of the high pressure. Elsewhere, the dominant high pressure is supporting light to gentle breezes and mostly 1 to 3 ft. For the forecast, the high pressure will drift westward over the weekend as low pressure meanders offshore of the Atlantic waters of Florida, providing tranquil marine conditions across the Gulf through early next week. CARIBBEAN SEA... A recent ship observation confirmed strong NE winds off Colombia, indicative of a large area of fresh to strong trade winds over the south-central and southwest Caribbean, with the strongest winds off northeast Colombia and the Gulf of Venezuela. Seas are 5 to 8 ft in this area. These enhanced winds are between high pressure centered across the central Atlantic extends W-SW to central Florida and low pressure over northern Colombia. The pressure gradient south of the high pressure is also supporting fresh winds just west of the Leeward Islands, south of Cabo Beata on the south coast of Hispaniola, and over the northern part of the Windward Passage. Elsewhere, generally moderate E winds and 3 to 5 ft seas are noted. No significant shower or thunderstorm activity is observed. For the forecast, the fresh to strong east winds over the central Caribbean are expected to continue across the central Caribbean through early Sat before the ridge weakens west of 75W. ATLANTIC OCEAN... Please see the Special Features section above for information related to the area of low pressure off northeast Florida. Elsewhere, an expansive 1027 mb high pressure near 34N43W is supporting mainly dry weather conditions across the basin. Fresh to locally strong E winds are probably active off the north coast of Hispaniola, reaching westward to the approaches of the Windward Passage, with 5 to 7 ft seas. Farther east, an area of fresh trade winds is found south of 25N and west of 45W due to the pressure gradient between the strong ridge and lower pressures over South America. Seas within this region are 6-8 ft. Another area of fresh to strong NE winds surrounds the Canary Islands east of 25W, with winds reaching near gale force between the islands. Seas are 5-7 ft east of 25W. Elsewhere, gentle to moderate flow prevails and seas of 4-6 ft. For the forecast, the current pattern will continue to support moderate to fresh trades south of 25N through Sun. Environmental conditions are forecast to be marginally conducive for additional development of the low off northeast Florida, with a medium chance for it to become a tropical cyclone over the weekend while it meanders just offshore of the southeastern United States. Regardless of development, showers and thunderstorms and moderate to fresh winds can be expected over the weekend off the Florida coast as the ridge remains in place. $$ Christensen