000 AXNT20 KNHC 222336 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Wed Jun 23 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 2200 UTC. ...TROPICAL WAVES... A tropical wave extends along 22W, from 17N southward, moving W at 10 kt. No significant convection is observed along this tropical wave. Another tropical wave extends along 39W from 11N southward, moving W at 5 to 10 kt. Scattered moderate convection is observed from 04N to 07N, between 37W-41W. A third tropical wave runs along 55W from 15N southward, moving W at 10 kt. Scattered moderate to isolated strong convection is noted from 09N to 14N between 50W and 60W. Enhanced showers and tstorms are possible over the SE Caribbean later this week. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal areas of Guinea-Bissau near 12N16W to 07N20W to 05N37W. The ITCZ continues from 05N40W to 07N53W. Scattered showers are seen from 03N to 05N between 25W-30W. GULF OF MEXICO... A cold front extends from central Alabama to southwest Louisiana, then is stationary just inland over the north Texas coast. An outflow boundary is evident from the Big Bend area of Florida to about 135 nm south of Mobile Bay. Convection is flaring along the outflow boundary and inland over coastal Mississippi and Alabama. This activity is supported by instability and lift ahead of an upper trough digging into the Deep South states. At the surface, a weak pressure gradient persists across the region, supporting gentle to moderate breezes over most of the area, except for locally moderate to fresh winds off the Yucatan Peninsula. Buoy and altimeter data indicates 4 to 6 ft seas over the western Gulf, 3 to 5 ft seas over the northeast Gulf, and 2 to 4 ft seas over the southeast Gulf. For the forecast, a ridge from the Atlantic will continue to dominate the Gulf region over the next several days. Pulsing fresh E to SE winds are expected each night into the early morning hours to the NW of the Yucatan peninsula through Thu night. CARIBBEAN SEA... A weak upper-level low centered over eastern Cuba and Jamaica is supporting areas of cloudiness across the central Caribbean south of Hispaniola and Puerto Rico. Along with daytime heating, this is also supporting a few thunderstorms across Hispaniola and eastern Cuba. Trade wind convergence is supporting a few thunderstorms over the far southwest Caribbean, mainly near San Andres Island. Observations from the Bay Islands confirm fresh to strong winds are active across the Gulf of Honduras, where seas may be reaching 5 to 7 ft. Ridging north of the area may also be supporting fresh to strong trade winds off the Guajira Peninsula of Colombia and in the Gulf of Venezuela. Seas are 4 to 6 ft over most of the remainder of the basin, except 2 to 4 ft in the lee of Cuba. For the forecast, the Atlantic high pressure combined with the Colombian low supports fresh to strong trades over the south- central Caribbean mainly at night through Wed night. Pulsing fresh to strong E to SE winds are expected in the Gulf of Honduras at night through Wed night. An active tropical with axis now along 55W is forecast to approach the Lesser Antilles by Thu, and move across those islands on Fri. Showers and thunderstorms remain disorganized in association with this wave. ATLANTIC OCEAN... Refer to the Tropical Waves section above for details on the tropical waves moving across the basin. West of 65W: A 1024 mb high near 29N60W extends surface ridging towards the northwest Bahamas. A line of showers and thunderstorms is noted off the northeast Florida coast, from 32N77W to near Cape Canaveral. Recent buoy data and earlier scatterometer data indicate gentle to moderate trades north of 22N along the ridge, with moderate to fresh trades farther south, possibly pulsing to 25 kt along the north coast of Hispaniola. Seas are 4 to 6 ft in open waters. For the forecast, fresh S to SW winds are expected across the waters off NE Florida through tonight ahead of a frontal boundary located over the SE of United States. A surface ridge will continue to dominate the area during the next several days. Fresh to locally strong winds are expected to pulse at night over Hispaniola adjacent waters including approaches to the Windward Passage through Fri night. East of 65W: a surface trough along 45W north of 20N bisects the subtropical ridge over the area. This pattern is supporting generally moderate trade winds across the region. Fresh to locally strong NE winds are noted along the coast of northwest Africa. Seas are generally 4 to 6 ft. $$ Christensen