358 AXNT20 KNHC 072339 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Sat Jul 8 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 1800 UTC surface analysis and satellite imagery through 2210 UTC. ...TROPICAL WAVES... The axis of an eastern Atlantic tropical wave is near 23W from 19N southward, moving west at around 10 kt and showing signs of accelerating in forward speed. Isolated convection is noted at E of the wave axis this time. The axis of a central Atlantic tropical wave is near 46W from 09N to 19N, moving west at 10-15 kt. No significant convection is noted at this time. The axis of an Atlantic tropical wave is along 60W-61W, from 19N southward, moving west at 10-15 kt. The 1200 UTC Upper Air Sounding from Barbados captured the wave passage this morning. Scattered moderate convection is located within 30 nm east of the wave axis, south of 20N. Scattered strong convection is seen ahead of the wave across much of northeastern Venezuela. The axis of a Caribbean Sea tropical wave is along 85W from 21N southward into the tropical Pacific, moving west at 10-15 kt. Scattered moderate isolated strong convection is noted south of a line from 15N83W to 11N75W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Africa near 19.5N16.5W to 07N31W. The ITCZ continues from 07N32W to 04.5N45W to 06N55W. Scattered showers are near the boundaries, but no deep convection is observed outside the tropical wave associated convection at this time. GULF OF MEXICO... 1017 mb high pressure is centered along the Louisiana coast near 30N92W. A low level trough lingers across the northern Gulf along 28N-29N, were scattered moderate convection continues to develop and shift eastward. Scattered strong convection is occurring across portions of the Yucatan Peninsula and southern Mexico. Light to gentle winds prevail across the basin, with seas of 2-4 ft. For the forecast, moderate to fresh winds will pulse north and west of the Yucatan peninsula each evening as a daily trough develops and moves offshore. Otherwise, weak high pressure situated over the eastern Gulf will support gentle to moderate breezes and slight seas through the middle of next week. CARIBBEAN SEA... Please see the TROPICAL WAVES section for information on convection and tropical waves. Fresh trades were detected by satellite scatterometer in the central Caribbean late this morning, where seas are currently 6-9 ft. Moderate to fresh winds prevail this afternoon across western portions, associated with the passing tropical wave. Seas are 4-7 ft W of 80W. Elsewhere in the E Caribbean, trades are gentle to moderate with 4-6 ft seas. Other than convection associated with the tropical wave, only isolated heavy showers dot the NW portions of the basin. For the forecast, the Atlantic ridge to the north is expected to remain modest into next week. This pressure gradient will produce fresh winds across the central Caribbean through early next week, pulsing to strong at night. Fresh winds will also pulse to strong in the Gulf of Honduras tonight and Sat night, then again Tue night. Generally moderate winds and seas are expected elsewhere. ATLANTIC OCEAN... 1019 mb high pressure persist near 25N64W, to the west of a persistent weak 1017 mb low pressure center near 28N58W. This low center continues to disrupt the Azores High to the NE from extending a ridge across the entire Atlc. Currently, the 1019 mb high extends a modest ridge to the central Bahamas. A weak middle level trough moving eastward off the middle Atlantic Seaboard is supporting scattered moderate isolated strong convection across the NW waters, from 26N to 30N and W of 65W, that is embedded in the convergent SW low level flow. SAL continues to dominate the Atlantic north of the Greater Antilles between 62W and 76W, to the S of 25N. Farther E, the tropical Atlantic is dominated by the subtropical high pressure, anchored by a 1027 mb high SW of the Azores near 34N36W. Gentle to moderate trade wind flow persists across the basin between 35W and the Lesser Antilles, with fresh to locally strong NE flow in the eastern Atlantic south of 26N. Seas are 4-7 ft across the trade wind zone, south of 22N, except locally 8 ft south of 10N between 48W and 52W. In the eastern Atlantic, seas are 5 to 8 ft, with peak seas of 9 to possibly 10 ft in the strong NE winds occurring to the northwest of the Cabo Verdes. Another significant SAL outbreak is moving across the eastern Atlantic, and dominates the atmosphere N of 08N and E of 46W. For the forecast west of 55W, weak ridging will continue along 25N, south of a trough that will persist off the Carolina and Georgia coasts. This pattern will support moderate to fresh SW winds north of 27N, and moderate E trade winds south of 22N, occasionally pulsing to 25 kt off Hispaniola through early next week. Light breezes will persist elsewhere. Looking ahead, the eastern Atlantic ridge will build modestly into the region Tue and Wed, and lift northward to 26N-27N. This will allow moderate to fresh ESE trade winds to expand from Hispaniola into the central Bahamas. $$ Stripling