000 AXNT20 KNHC 110607 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Sun Jul 11 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 0430 UTC. ...TROPICAL WAVES... A newly analyzed Atlantic tropical wave is near 22W from 12N southward and moving W at 10 to 15 kt. Moderate convection is from 03N to 09N between the African coast and 26W. Another Atlantic tropical wave is along 37W from 09N southward and moving W near 15 kt. No significant convection is noted with this wave. A Caribbean tropical wave is near 61W from 21N southward, just W o the Lesser Antilles and moving W near 15 kt. Aided by divergent upper-level winds aloft, scattered showers are present from Jamaica and central Hispaniola southward to northern Columbia and Venezuela. Another Caribbean tropical wave is along 78W from 14N southward to eastern Panama, and moving W at 15 to 20 kt. Scattered moderate to isolated strong convection is flaring up over the SW Caribbean basin. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from Senegal and Guinea-Bissau near 12N16W to 03N28W. Segments of the ITCZ extend from 03N28W to 03N34W then from 03N40W to near the French Guiana-Brazil border. There is no significant convection other than the ones mentioned in the Tropical Wave section above. GULF OF MEXICO... A surface ridge extends westward across the N Gulf from a 1020 mb high pressure centering near 28N84W to S Texas. Divergent upper- level winds are coupling with convergent SE winds along the surface ridge to trigger scattered convection over the NW corner of the Gulf. Otherwise, light to gentle SE to S winds and seas of 2 to 4 ft prevail across the N Gulf. Gentle to moderate E to ESE winds and seas of 3 to 5 ft are present over the S Gulf. For the forecast, moderate SE winds persist over the western Gulf between a ridge extending from the western Atlantic to the north central Gulf and lower pressure over northern Mexico. The ridge will lift north of the area through Mon. This will support gentle to moderate winds and slight to moderate seas persist through mid week. The exception will be fresh to occasionally strong winds off the northwest Yucatan Peninsula and eastern Bay of Campeche during overnight hours through mid week, related to the surface trough that forms during the late afternoon each day. CARIBBEAN SEA... Please see the Tropical Wave section for information on convection. Moderate to fresh trade winds and 8 to 10 ft seas are noted across the central Caribbean, driven by the pressure gradient between the subtropical high north of the area and lower pressure over Colombia and W Venezuela. In the E Caribbean, Mainly moderate trades and seas of 5 to 7 ft are evident. Gentle to moderate trades and seas of 4 to 6 ft are found elsewhere. For the forecast, strong Atlantic high pressure ridge will begin to drift northward tonight and Sun and allow strong to near gale force tradewinds across the south-central Caribbean to weaken through Mon. Strong trades in the Gulf of Honduras will diminish Sun, but fresh trades will pulse nightly through the middle of next week. A large tropical wave approaching the Lesser Antilles today will bring a surge in wind and waves behind it as it moves across the E Carib tonight through late Sun, and across the central Carib Mon through Wed. ATLANTIC OCEAN... Please see the section above for information the tropical waves moving across the basin. An upper-level low ESE of Bermuda at 31N53W is triggering scattered moderate convection from 24N to 29N between 49W and 56W. Otherwise, a subtropical high centered north of the area continues to dominate the tropical Atlantic. Light to gentle winds and seas of 4 to 5 ft are found near the ridge axis N of 28N between 43W and the E Florida coast. Moderate to fresh ENE to E trades and seas of 6 to 8 ft are seen between 10N and 28N from 27W to the Bahamas and Less Antilles. Light to gentle NE to E trades and seas of 4 to 6 ft prevail elsewhere. For the forecast west of 65W, a surface ridge from Bermuda to central Florida will lift north through Mon and support moderate to fresh E winds south of the ridge axis, with winds pulsing to fresh to strong along the north coast of Hispaniola mainly during the evenings into mid week. A large tropical wave moving into the eastern Caribbean will bring a surge in wind and waves to the Atlantic waters north of the Leeward Islands tonight through Mon, then through the southern Bahamas late Mon and Tue. $$ Chan