000 AXNT20 KNHC 112349 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 2328 UTC Tue Aug 11 2020 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 32N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 1800 UTC surface analysis and satellite imagery through 2300 UTC. ...SPECIAL FEATURES... Tropical Depression Eleven is centered near 11.7N 40.0W at 11/2100 UTC or 960 nm WSW of the Cabo Verde Islands moving W at 14 kt. Estimated minimum central pressure is 1007 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. Scattered moderate and isolated strong convection is noted within 180 nm in the NW semicircle. The westward motion is expected to continue through Wednesday. A west-northwestward motion at a similar forward speed is forecast to begin Wednesday night and continue through the rest of the week. Some strengthening is forecast during the next 48 hours, and the depression is expected to become a tropical storm by Wednesday night. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPAT1.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMAT1.shtml for more details. ...TROPICAL WAVES... An eastern Atlantic tropical wave axis is near 25W south of 18N, moving W at 10-15 kt. Scattered moderate and isolated strong convection is noted from 08N-14N between 17W-24W. A central Atlantic tropical wave axis is near 58W south of 22N, moving W at 10-15 kt. This wave is well-depicted in satellite imagery, despite the lack of significant convection. At this time, scattered showers are noted over the northern portion of the wave. A west-central Caribbean tropical wave axis is along 78W south of 20N, moving W at about 10 kt. No significant shower activity is noted in association with this wave. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Senegal near 17N16W to 12N26W to Tropical Depression Eleven near 12N40W. The ITCZ extends from near 10N44W to 10N56W. Aside from the convection related to the tropical waves described above, no other significant convection is noted. GULF OF MEXICO... Surface ridging prevails across the basin, anchored by a 1017 mb high centered near 29N91W. Light to gentle winds persist across the waters N of 25N, while moderate winds are noted offshore of the Yucatan peninsula in the Bay of Campeche. The high pressure centered over the NE Gulf will maintain a ridge across the northern waters this week, resulting in gentle to moderate winds with slight seas across much of the area. Fresh to locally strong winds are expected each evening for the next several nights in the eastern Bay of Campeche near the Yucatan peninsula due to local effects. CARIBBEAN SEA... Refer to the section above for details on the tropical wave moving across the basin. Recent GOES-16 satellite imagery show no significant convection over the Caribbean Sea currently. Fresh to strong trade winds persist in the south-central waters near the coast of Colombia and in the Gulf of Venezuela. Elsewhere, gentle to moderate winds prevail. Fresh to strong trade winds will prevail across the south- central Caribbean waters through Fri night, with near gale-force winds expected to pulse near the coast of Colombia and in the Gulf of Venezuela for the next couple nights. Fresh winds will pulse for the next several nights through the Windward Passage. A tropical wave approaching the eastern extent of an active phase of the Madden-Julian Oscillation (MJO) later this week will support enhanced moist low-level convergence and the potential for heavy rainfall across the SW Caribbean. This could result in localized flooding over portions of Nicaragua, Costa Rica, Panama, and W Colombia from Thu to Sun. ATLANTIC OCEAN... Please see the sections above for more details on Tropical Depression Eleven and the tropical waves moving across the basin. A surface trough lingers between the Bahamas and Bermuda, with isolated showers north of 30N between 68W-77W. Overall, the pressure pattern remains weak across the subtropical Atlantic, with light to gentle winds over the waters north of 25N. Moderate to locally fresh trades prevail across the central tropical Atlantic, south of 1023 mb high pressure near 33N44W. Earlier altimeter data indicated seas were 6-8 ft in this region. Farther east, fresh northerly winds are noted from the Canary Islands southward to 20N off the coast of Africa. The weak low pressure trough well offshore of the NW Bahamas will dissipate tonight. Fresh winds will pulse each night near the coast of Hispaniola and over the approach to the Windward Passage. $$ Landsea/ERA