000 AXNT20 KNHC 011555 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Tue Aug 1 2023 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 1200 UTC surface analysis and satellite imagery through 1550 UTC. ...SPECIAL FEATURES... Central Tropical Atlantic (Invest AL96): A 1014 mb low pressure is centered near 25.7N 54.9W or about 650 nm northeast of the northern Leeward Islands, moving NW at 10 to 15 kt. Scattered moderate convection is observed from 23N to 28N between 51W and 55W. Strong to near-gale force winds accompany the low, mainly in the E semicircle, with seas of 9 to 12 ft. Environmental conditions still could support tropical cyclone formation during the next two to three days while the system moves northwestward and then northward at 10 to 15 kt over the central subtropical Atlantic. Formation chance through 48 hours is medium. Please read the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...TROPICAL WAVES... An eastern Atlantic tropical wave extends along 25W from 07N to 21N, moving west at around 15 kt. No significant convection is observed near this wave due to the presence of dry Saharan dust. A central Atlantic tropical wave extends along 44W from 03N to 19N, moving west at 20-25 kt. No significant convection is observed near this wave. A central Caribbean tropical wave extends along 73W from Haiti to Colombia, moving west at around 15 kt. No significant convection is observed near this wave. A western Caribbean tropical wave over SE Mexico and central America extends along 80W, moving west at 10 to 15 kt. Scattered moderate convection is observed in the Gulf of Honduras. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Africa near 21N17W to 08N50W. The ITCZ continues from 08N50W to 07N58W. Scattered moderate convection is observed from 07N to 10N between 37W and 41W. Additional convection south of the monsoon trough is isolated and weak. A portion of the eastern Pacific monsoon trough extends across the SW Caribbean, generating scattered moderate and isolated strong convection west of 79W and south of 13N. GULF OF MEXICO... A surface trough extends from the Bay of Campeche to the central Gulf of Mexico. Isolated moderate convection is observed from 23N to 25N between 85W and 91W. Similar convection is observed along the west coast of Florida. Otherwise, a weak pressure gradient persists across the region. Winds are light to gentle across the basin with 1-2 ft seas. For the forecast, weak surface ridging prevails across the northern Gulf. The ridge will stay in place over the next few days, supporting gentle to moderate winds over most of the basin. A thermal trough will emerge off the Yucatan Peninsula and will produce nightly moderate to fresh winds by the middle to latter part of the week. High pressure will shift SE into the east Gulf today and Wed and allow for moderate return flow to develop across the W Gulf Wed night through Fri. CARIBBEAN SEA... Please refer to the Tropical Waves and Monsoon Trough/ITCZ sections above for information on convection in the Caribbean Sea. The gradient between subtropical high pressure and lower pressure in the SW Caribbean is partially disrupted by Invest AL96. Moderate to fresh with locally strong easterly trade winds are noted in the majority of the basin with 3-6 ft seas. Conditions are more favorable in the NW Caribbean with gentle to moderate winds and 2-4 ft seas. For the forecast, fresh to locally strong trades in the south- central Caribbean, and moderate to fresh winds elsewhere in the central Caribbean will persist through most of the week. Fresh to strong trades will develop in the S central Caribbean Thu through at least Sat night. ATLANTIC OCEAN... Please refer to the Special Features section for details on Invest AL96 well NE of the Leeward Islands that has potential for tropical cyclone development. A surface trough and upper level divergence is supporting scattered moderate convection north of 24N and west of 65W. Otherwise subtropical high pressure prevails across the basin. A ridge extends from the central Atlantic to the Florida Straits. North of the ridge winds are moderate from the SW. South of the ridge, winds are moderate from the SE. Winds are gentle within the ridge axis. Seas are 3-5 ft across the western Atlantic. In the central Atlantic, Invest AL96 is supporting seas to 12 ft with 8ft or greater seas from 24N to 30N between 50W and 57W. Otherwise easterly winds are moderate with 5-7 ft seas. In the eastern Atlantic the gradient between subtropical high pressure and lower pressure over Africa is supporting fresh to locally strong NE winds and 6-8 ft seas. For the forecast west of 55W, moderate to locally fresh trade winds will continue S of 23N through early today before diminishing. Fresh trades will pulse this afternoon and early evening N of Hispaniola and over the Windward Passage. A weak frontal trough will sink S into the waters offshore of NE Florida tonight and move SE and reach from near Bermuda to the northwest Bahamas by Thu. Ridging will dominate the basin by the end of the week into the weekend. $$ Flynn