Tropical Weather Discussion

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Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 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 0000 UTC surface analysis and satellite imagery through 0550 UTC. ...SPECIAL FEATURES... A 1015 mb low pressure centered well east of Jacksonville, Florida, near 30N78W has a trough that extends S-SW to near Stuart, Florida. This low continues to produce showers and thunderstorms. This system has become better organized since yesterday, and a tropical depression could Form over the weekend while the low meanders offshore or near the Florida peninsula. Interest in Florida should monitor the progress of this system. There is a medium chance for development in the next 5 days. Please read the latest Tropical Weather Outlook at hurricanes.gov, for more information. Heavy Rainfall in Southern Central America: High moisture content, persistent strong trade wind flow, and favorable conditions aloft will continue to 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 to strong convection is noted along the Caribbean coast from southern Nicaragua through western Panama. ...TROPICAL WAVES... An Atlantic tropical wave is analyzed along 58W, from south of 19N, moving W 10 to 15 kt, approaching the Lesser Antilles. A few showers and thunderstorms are noted in the vicinity of the wave axis. Patches of Saharan dust are following the tropical wave over the tropical Atlantic. A Caribbean tropical wave is analyzed along 71W, from Haiti 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 western Cuba. No significant convection is associated with this wave. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic Ocean near Guinea-Bissau near 11N16W to 06N30W. The ITCZ continues from 06N30W to 07N51W. Scattered moderate convection is noted over the eastern Atlantic from 06N to 11N between 13W and 25W, and over the western Atlantic from 06N to 12N between 43W and 53W. GULF OF MEXICO... A line of showers and strong thunderstorms have moved offshore the Florida Panhandle extending from the Big Bend to south of Pensacola, Florida. Some of the stronger storms could produce gust up to 34 kts with frequent lightning. These strong thunderstorms will remain over open waters tonight. Across the northwest Gulf, a 1019 mb high pressure is centered near 27N92W, which is dominating the weather pattern across much of the Gulf. To the southeast, a surface trough is analyzed from 22N87W southwest into the Yucatan Peninsula. Scattered moderate to strong convection is noted in the west coast of the Yucatan Peninsula near the trough. Moderate to locally fresh S winds are noted along the Texas coast, west of the high pressure. Elsewhere, the dominant 1019 mb high pressure is supporting light to gentle breezes and mostly 1 to 3 ft across the basin. For the forecast, the high pressure in the northwest Gulf of Mexico will drift westward over the weekend as low pressure meanders offshore of the Atlantic waters of Florida. This is expected to produce tranquil marine conditions across the Gulf through early next week. CARIBBEAN SEA... Upper low centered north of Hispaniola near 21N83W interacting with the tropical wave to the east moving into the NE Caribbean is supporting squalls and strong thunderstorms to develop north of the U.S. Virgin Island and into the northern waters of Puerto Rico. Expect this activity to increment tonight into Saturday. Latest scatterometer indicates a large area of fresh to strong trades winds over the south-central and southwest Caribbean, with the strongest winds off northeast Colombia. 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. Fresh winds are also noted 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. For the forecast, high pressure centered across the central Atlantic extends W-SW to the NW Bahamas tonight. This ridge will weaken through early next week as the high shifts slowly NE and low pressure persists offshore of the NE Florida coast. This will lead to a gradual diminishing in the strength of tradewinds across the basin. Look for scattered squalls and tstms across the NE Caribbean tonight and Sat associated with a fast-moving tropical wave. ATLANTIC OCEAN... Please see the Special Features section above for information related to the area of low pressure off northeast Florida. Upper low centered north of Hispaniola near 21N83W interacting with the tropical wave to the east moving into the NE Caribbean is supporting squalls and strong thunderstorms to develop north of the U.S. Virgin Island and in the northern waters of Puerto Rico. Moderate to strong Convection is starting to increase north of Puerto Rico to 22N between 61W to 66W. Expect this activity to increment today as tropical wave moves across the eastern Caribbean. Elsewhere, an expansive 1028 mb high pressure near 34N41W is supporting mainly dry weather conditions across the remainder of 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 6 ft seas. Farther east, an area of fresh trade winds is found south of 25N and west of 43W 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, moderate to fresh trades will prevail south of 25N through Sun. Low pressure near 30N78.5W 1015 mb has a trough that extends S-SW to SE Florida. Environmental conditions are forecast to be marginally conducive for additional development of this low, with potential for it to become a tropical depression over the weekend while it meanders just offshore of Florida. Scattered squalls and tstms associated with a fast moving tropical wave will move across the SE waters and north of the Greater Antilles tonight through Sat. MTorres