072 AXNT20 KNHC 231803 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Sat Oct 23 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 1200 UTC surface analysis and satellite imagery through 1630 UTC. ...TROPICAL WAVES... An Atlantic tropical wave is near 51W from 16N southward to near the French Guiana-Brazil border, and moving W at 15 to 20 kt. Scattered showers and isolated thunderstorms are noted over NW French Guiana and adjacent waters. A Caribbean tropical wave is along 68W from 18N southward to W Venezuela, and moving W near 20 kt. Subsidence and drier air aloft is hindering any significant convection near this wave. Another Caribbean tropical wave is near 76W from SE Cuba southward across Jamaica to NW Colombia, and moving W at 15 to 20 kt. Scattered showers and thunderstorms are occurring across W Colombia, W Panama and nearby waters. A third Caribbean tropical wave is along 84W from 21N southward across Honduras, Nicaragua and Costa Rica to the Pacific Ocean; and moving W near 15 kt. Scattered showers and isolated thunderstorms are seen over the SW Caribbean Sea, including the coast of Nicaragua and Costa Rica. ...MONSOON TROUGH/ITCZ... A monsoon trough exits through the African coast near Guinea- Bissau/Guinea border at 11N15W through a 1011 mb low near 10N16W to well S of the Cabo Verde Islands at 07N22W. The ITCZ then continues from 07N22W to 04N42W. Scattered to numerous moderate to isolated strong convection is found near the monsoon trough from 04N to 08N between 14W to 29W. Scattered showers and isolated thunderstorms are evident near the low from 09N to 14N between the NW African coast and 19W. Based on the latest analysis, no significant convection is present near the ITCZ. ...GULF OF MEXICO... A surface trough and an embedded 1010 mb low pressure at the W Bay of Campeche near 21N94W are generating scattered showers and isolated thunderstorms over the N Bay of Campeche and near the N Yucatan Peninsula. A modest stationary front curves southwestward from N Florida across the N Gulf to near New Orleans. Scattered showers are present just S of this boundary from the NW Gulf east-southeastward through the central Gulf to central Florida. Gentle to moderate winds and seas of 2 to 4 ft are found across much of the Gulf, except locally fresh winds with seas up to 5 ft near showers and thunderstorms. For the forecast, the stationary front will linger across the N central and NE Gulf today before dissipating tonight. Gentle to moderate winds will prevail across the basin through the weekend and become light to gentle by early next week. ...CARIBBEAN SEA... Refer to the Tropical Waves section for details on convection across the Caribbean Basin. Otherwise, the latest satellite scatterometer and model data reveal moderate to fresh ENE to E trades with seas of 6 to 8 ft across the central and E basin. Moderate to gentle E to ESE trades and seas of 2 to 5 ft prevail for the W basin. For the forecast, high pressure N of the area will support fresh to locally strong trades E of the Windward Islands and across the E Caribbean through the early next week. Winds are also expected to pulse fresh to strong in the Venezuela Basin tonight through Mon evening. By Tue and Wed, gentle to moderate trade winds are expect to prevail across the basin. ...ATLANTIC OCEAN... A surface trough curves southwestward from SW of Bermuda at 28N71W across the central Bahamas to N Cuba. Scattered showers and thunderstorms are evident from the central Bahamas northeastward to S and E of Bermuda. Farther E, a shear line stretches west- southwestward from well SW of the Azores across 31N39W to SE of Bermuda at 29N53W. Scattered showers and isolated thunderstorms are noted N of 28N between 40W and 53W. Refer to the Tropical Waves and Monsoon Trough/ITCZ sections above for additional convection across the Atlantic Basin. Gentle to moderate with locally fresh trades and seas of 5 to 8 ft are present N of 16N between the NW African coast and 71W. W of 71W, gentle to moderate S to SW winds and seas at 2 to 4 ft are seen from the Greater Antilles northward to 31N. Moderate to fresh NE trades and seas of 8 to 10 ft are found from 05N to 16N between 36W and the Lesser Antilles. Gentle to moderate with locally fresh winds and seas at 5 to 7 ft prevail for the rest of the basin. The Cumbre Vieja volcano, on the island of La Palma in the Canary Islands, has been erupting since 19 September 2021. Continues ash emission is noted with small column height. Medium to high volcanic ash concentration in the vicinity of the volcano. Marine and aviation interests should monitor this ongoing situation by reading the Volcanic Ash Advisory issued by Meteo- France, at http://vaac.meteo.fr/volcanoes/la-palma/. For the forecast W of 65W, a trough extending across the NW Bahamas and off the southeast Florida coast will support convection across the region today. Meanwhile, a stationary front stretches across N Florida and adjacent Atlantic waters from 31N78W to 29N81W. This front will slowly meander southward toward S Florida and the NW Bahamas today and stall by Sun. The front is expected to dissipate by Mon morning. Moderate to locally fresh winds will develop N of this boundary on Sun off the Florida coast. Expect showers and thunderstorms along this boundary through the weekend. $$ Chan