000 AXNT20 KNHC 232339 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Tue Aug 24 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 2300 UTC. ...TROPICAL WAVES... An Atlantic tropical wave extends its axis along 23W from 19N southward and moving W at 10 to 15 kt. Scattered moderate convection is noted from 02N to 10N between 22W and 28W. Some slow tropical development will be possible over the next several days while the disturbance moves westward to west-northwestward over the eastern tropical Atlantic. A well defined Atlantic tropical wave is near 40W from 20N southward and moving W at 10 to 15 kt. Scattered showers are noted from 07N-21N between 34W and 44W. Little tropical development is expected during the next couple of days due to only marginally conducive ocean temperatures. Thereafter, however, some gradual development will be possible through the end of the week while the system over the central Atlantic. A weak Atlantic tropical wave is along 54W from 18N southward and moving W near 15 kt. Much drier air at mid and upper levels is hindering any significant convection near this wave. A robust Caribbean tropical wave is near 66W from 20N southward across the Virgin Islands to E Venezuela, and moving W near 10 kt. Enhanced by strong trade-wind convergence in the vicinity, scattered showers and isolated thunderstorms are occurring across the S central and SE Caribbean Basin, and farther E into the Atlantic from 9N to 14N between 55W and the Windward Islands. A broad low is expected to form with this wave over the southwestern Caribbean by late week. Thereafter, environmental conditions are forecast to become favorable for gradual development while the system moves over the northwestern Caribbean. Another Caribbean tropical wave is along 84W from 20N southward into the E Pacific, moving W at 10 to 15 kt. Scattered moderate convection prevails over land south of 16N between 82W and 87W. A tropical wave is over the E Bay of Campeche near 92W from 21N southward across S Mexico and Guatemala into the E Pacific, and moving W near 15 kt. Scattered moderate to strong convection prevails south of 22N between 89W and 95W. ...MONSOON TROUGH/ITCZ... A monsoon trough extends from the African coast near 15N17W through a 1011 mb low pressure near 13N42W to 13N44W. Aside from the convection described in the tropical waves section above, no other convection is noted at this time. ...GULF OF MEXICO... A surface ridge prevails across the basin anchored over the western Atlantic. Convergent surface winds N of the ridge axis are coupling with modest divergence aloft to trigger scattered showers and isolated thunderstorms from near New Orleans eastward including the Florida peninsula. An upper-level low over E central Mexico coupled with the northern extension of a tropical wave is enhancing similar conditions over the SW Gulf, including the W Bay of Campeche. Moderate to locally fresh winds and seas up to 4 ft are expected near strong thunderstorms. Otherwise, light to Gentle E to ESE winds associated with the ridge and seas at 1 to 3 ft prevail across much of the Gulf. For the forecast, high pressure will dominate the basin through Fri producing mainly gentle to moderate E to SE winds. Fresh winds will likely pulse west of the Yucatan Peninsula tonight and again Tue night. ...CARIBBEAN SEA... Refer to the section above for details on the tropical waves moving across the basin. Convergent trade winds are causing scattered showers and isolated thunderstorms over the W central basin, N of Panama and Colombia. The latest satellite scatterometer and altimeter data reveal fresh to strong NE to E trade winds and seas at 5 to 8 ft across the central and E basin. Gentle to moderate trades and seas of 2 to 4 ft prevail for the rest of the basin. For the forecast, fresh to strong trade winds will dominate most of east and central Caribbean through midweek building seas to 8 to 10 ft. Fresh to locally strong winds are also expected in the Windward passage through Tue night. A tropical wave currently over the eastern Caribbean seas is likely to form a broad low pressure in the SW Caribbean Sea late this week. ...ATLANTIC OCEAN... Refer to the section above for details on the tropical waves moving across the basin. Enhanced by an upper-level trough along the US E Seaboard near 34N74W, convergent SE winds are creating scattered showers off the Georgia-N Florida coast, N of 28N and W of 74W. The Atlantic ridge curves westward from the 1023 mb Azores high near 34N24W to the Bermuda high near 32N63W. These features continue to provide gentle to moderate winds and seas of 3 to 5 ft N of 23N between 23W and the Georgia-Florida coast. Moderate to fresh with locally strong trade winds and seas at 7 to 9 ft are found near the Canary Islands N of 16N between the NW African coast and 23W, and W of the Cape Verde Islands from 08N to 22N between 34W and 40W. Moderate to fresh trades and seas of 5 to 6 ft are found from 10N to 23N between 50W and the Lesser Antilles. Gentle to moderate SE to S winds and seas at 5 to 7 ft prevail for the rest of the Atlantic Basin. For the forecast W of 65W, high pressure located near Bermuda will dominate the forecast region through at least Wed. A surface trough is forecast to approach from the E Thu, possibly reaching the NE waters Fri. Fresh to locally strong winds are expected N of Hispaniola including the approaches to the Windward Passage through Tue night. The pressure gradient could increase some across the SW N Atlantic Tue night into Wed between high pressure located just N of Bermuda and the approaching surface trough. $$ ERA