000 AXNT20 KNHC 240558 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Thu Jun 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 0530 UTC. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 29W/30W, from 17N southward, moving W from 10 knots to 15 knots. Precipitation: broken to overcast multilayered clouds and possible rainshowers cover the areas that are from 14N to 22N between 25W and 33W. Any other significant deep convective precipitation is related more to the monsoon trough. An Atlantic Ocean tropical wave is along 44W/45W from 12N southward, moving W 10 knots. Precipitation: isolated moderate is within 300 nm on either side of the tropical wave, from 01N to 10N. An Atlantic Ocean tropical wave is along 56W/57W from 15N southward, moving W from 5 knots to 10 knots. A 1012 mb low pressure center is along the tropical wave near 12N. Precipitation: scattered strong is within 165 nm of the center in the E quadrant. The sea heights range from 4 feet to 6 feet from 20N southward between 50W in the Atlantic Ocean and 62W in the Caribbean Sea. Fresh-to-strong winds are from 60 nm to 180 nm of the center in the NE quadrant. The low pressure center is about 160 nm to the ESE of Barbados, and about 210 nm to the ENE of Tobago. Increasing upper level winds are likely to prevent more development of this system, while it moves west-northwestward about 10 mph. It is possible that low pressure center and tropical wave may produce increased rainshower activity and some gusty winds, when it moves across the Lesser Antilles on Friday. A Caribbean Sea tropical wave is along 71W/72W from 19N southward, moving W 10 knots. Broad upper level cyclonic wind flow covers the Caribbean Sea, to the west of the line that runs from the Windward Passage to Nicaragua. Precipitation: widely scattered moderate to isolated strong, in individual clusters, covers the areas that are from Jamaica to Cuba between Hispaniola and 84W. Fresh winds are within 135 nm to the south of Hispaniola, and within 150 nm to the east of the tropical wave. Fresh winds also are within 60 nm to the north of Hispaniola between 71W and the northern part of the Windward Passage. The sea heights range from 4 feet to 6 feet within 150 nm on either side of the tropical wave. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal areas of Guinea-Bissau near 11N15W, to 07N20W, 06N25W, 06N31W, and 05N35W. The ITCZ is along 05N35W 03N43W. Precipitation: scattered moderate to widely scattered strong is within 90 nm to the south of the coast of Africa from 07W eastward. Widely scattered moderate to isolated strong is within 250 nm to 500 nm to the south of the monsoon trough between 10W and 30W. Isolated moderate to locally strong is elsewhere, from 10N southward from 60W westward. GULF OF MEXICO... A stationary front is along 31N/32N between 80W in the Atlantic Ocean, and northern Louisiana. Precipitation: widely scattered moderate to isolated strong in clusters covers the areas that are from Cuba northward between 73W in the Atlantic Ocean and 88W in the Gulf of Mexico. A diurnal surface trough is inland, from central Guatemala, through the Isthmus of Tehuantepec of southern Mexico, beyond 20N100W. Precipitation: numerous strong is inland, and in the coastal waters, between the NW sections of El Salvador and Mexico, between 88W and 100W. A surface ridge passes through central Florida near 28N82W, toward the NW corner of the Gulf of Mexico, toward the coast of Mexico near 21N98W. The sea heights have been ranging from 3 feet to 4 feet from 90W westward, and from 2 feet to 3 feet from 90W eastward. High pressure will prevail across the northern waters. A diurnally-induced trough will develop in the Yucatan Peninsula each evening. This will result in a pulsing of fresh E to SE winds each night NW of the Yucatan Peninsula through Thursday night. CARIBBEAN SEA... A Caribbean Sea tropical wave is along 71W/72W from 19N southward, moving westward 10 knots. Broad upper level cyclonic wind flow covers the Caribbean Sea, to the west of the line that runs from the Windward Passage to Nicaragua. Precipitation: widely scattered moderate to isolated strong, in individual clusters, covers the areas that are from Jamaica to Cuba between Hispaniola and 84W. Fresh winds are within 135 nm to the south of Hispaniola, and within 150 nm to the east of the tropical wave. Fresh winds also are within 60 nm to the north of Hispaniola between 71W and the northern part of the Windward Passage. The sea heights range from 4 feet to 6 feet within 350 nm to 450 nm on either side of the tropical wave. The monsoon trough is along 10N/11N between 74W in Colombia, and beyond NW Costa Rica, into the eastern Pacific Ocean. Precipitation: isolated moderate is from 14N southward from 70W westward, in the Caribbean Sea. Widely scattered moderate to isolated strong, in individual clusters, is within 300 nm to the south of the monsoon trough, between the 71W/72W tropical wave and 85W. A ridge of high pressure to the north of the area, combined with the low presssure that is in Colombia, will continue to support fresh to strong trade winds in the south central Caribbean Sea, and in the Gulf of Honduras, through tonight. The ridge will shift northward, loosening the pressure gradient, with a modest decrease in the wind speeds in these areas. A tropical wave, that is moving across the offshore tropical Atlantic Ocean waters, will interact with an upper level trough, which will enhance convection with locally higher winds and seas. ATLANTIC OCEAN... A surface trough covers the area that is from 22N to 31N between 48W and 51W. An upper level cyclonic circulation center is near 27N53W, about 120 nm to the west of the surface trough. Precipitation: widely scattered moderate to isolated strong is from 25N to 31N between the surface trough and 56W. A surface ridge extends from a 1025 mb high pressure center that is just to the north of Bermuda, to 30N74W, to central Florida near 28N82W. Fresh-to-strong N and NE winds are within 250 nm of the coast of Africa from the northern sections of Senegal to 25N off the coast of the Western Sahara. The sea heights have been ranging from 5 feet to 7 feet in the same area. A surface trough extends across the NW waters, with a surface ridge along 26W. The ridge will start to shift northward tonight, pushing the trough westward into the SE United States by Friday night. A surface trough, the result of an interaction of a tropical wave and upper level trough, will move north of the Lesser Antilles Friday night. The trough will continue to move westward across the southern waters to the north of Puerto Rico on Saturday, and to the north of Hispaniola on Sunday. $$ mt/ERA