000 AXNT20 KNHC 180913 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Mon Oct 18 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 0600 UTC surface analysis and satellite imagery through 1000 UTC. ...TROPICAL WAVES... The axis of a tropical wave is near 23W/24W from 02N to 17N, moving westward at 10-15 kt. Scattered moderate convection is from 08N to 10N between 20W and 26W. The axis of a tropical wave is near 43W/44W from 02N to 19N, moving westward at 10-15 kt. Scattered moderate convection is noted from 03N to 12N between 40W and 46W. The axis of a tropical wave is near 57W south of 20N, moving westward at 10-15 kt. Scattered moderate convection is seen from 12N to 20N between 55W and 60W, mainly associated with a sharp upper- level trough north of the tropical wave. The axis of a tropical wave is near 78W south of 20N, moving westward at 10-15 kt. Isolated moderate convection is noted from 11N to 17N between 75W and 80W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends off the coast of Africa near 12N17W to 07N25W. The ITCZ continues from 07N25W to 05N33W to 08N42W. It resumes from 08N45W to 06N50W. In addition to the convection mentioned above in the Tropical Waves section, scattered moderate convection is observed from 02N to 08N between 30W and 40W. Scattered moderate isolated strong convection is noted from 05N to 10N between 46W and 50W. GULF OF MEXICO... A cold front extends from SW Florida to 22N99W then becomes stationary to the Bay of Campeche. Winds off Veracruz have diminished below gale force, with fresh to strong winds now prevailing. Seas over this area are in the 8-11 ft range. Elsewhere, gentle to moderate winds prevail across the Gulf waters. Seas are in the 4-7 ft range. For the forecast, the aforementioned cold front will continue moving SE today. Winds off of Veracruz, Mexico are expected to further diminish today. Winds across the Gulf will gradually veer to the E late today through Tue as the front becomes aligned from just offshore of the N Yucatan Peninsula through the Straits of Florida and dissipates. CARIBBEAN SEA... A weak pressure pattern prevails across the Caribbean waters. Light to gentle winds and seas of 1-3 ft prevail across much of the Caribbean waters. For the forecast, the weak pressure gradient across the Caribbean basin will continue to lead to tranquil marine conditions today. A cold front across the NW Atlc will move SE through early Wed before stalling from near 25N65W to the Straits of Florida. High pressure building in the wake of the front will bring a return to moderate trade winds to the Caribbean tonight through Tue and then moderate to fresh winds late Wed. ATLANTIC OCEAN... A cold front extends across the Atlantic waters from near 31N70W to South Florida. Fresh to locally strong north to northeast winds are noted behind the front. Seas with these winds are in the 6-8 ft range. Gentle to moderate winds prevail within 420 nm east of the front. Farther east, a cold front extends from near 31N30W to 25N40W, then becomes stationary to 23N46W and transitions to a trough to near 20N56W. Scattered moderate convection is observed within 120 nm SE of the fronts. Elsewhere over the tropical and subtropical waters north of 20N, light to gentle winds prevail. Seas are in the 6-7 ft range north of 26N and between 27W and 40W, and 3-6 ft elsewhere over the open waters north of 20N. Over the tropical waters south of 20N, gentle to moderate winds and seas of 4-6 ft prevail. The Cumbre Vieja volcano, on the island of La Palma in the Canary Islands, has been erupting since 19 September 2021. Light to moderate volcanic ash is expected in the area east of the volcano, while high ash concentrations are close to 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 west of 65W, the cold front extending from 31N70W to SE Florida will reach from near Bermuda to the Straits of Florida this morning. Expect fresh to strong N to NE winds behind the front through this morning. High pres will shift ESE across the W Atlc along 31N-32N Tue through Wed while the front stalls from near 25N65W to the Straits of Florida. $$ AL