000 AXNT20 KNHC 152106 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Tue Nov 16 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 2000 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coastal border of Guinea and Sierra Leone to 09N16W. The ITCZ continues from 09N16W to 07N25W, then resumes west of a surface trough from 08N30W to 03N48W. The surface trough extends from 11N27W to 05N29W. Isolated to scattered moderate convection is noted from 04N to 13N between 18W and 29W, and from 05N to 13N between 29W and 37W. GULF OF MEXICO... 1025 mb high pressure is centered along the coast of south-central Louisiana near 29N91W. Moderate to locally fresh NE winds dominate the southeast Gulf, with moderate SE-S return flow in the northwest Gulf. Light to gentle winds under ridging prevail elsewhere. Seas of 4 to 5 ft prevail in the southeast Gulf, with seas of 3 ft or less elsewhere in the basin. For the forecast, high pressure centered over the north-central Gulf near the Louisiana coast will strengthen some as it shifts to the southeastern United States on Tue. Fresh to strong east winds will develop over the southeastern Gulf and Straits of Florida Tue through early Thu along with building seas. A cold front will move across the NW Gulf Thu, then across the rest of the Gulf through Fri afternoon. The front will be followed by mainly fresh northeast winds, except for fresh to strong northwest to north winds along and just offshore the coast of Mexico Thu night and Fri. These winds will be confined to offshore Veracruz Fri night into early on Sat. Scattered showers and isolated thunderstorms are expected ahead of this front. CARIBBEAN SEA... A stationary front reaches from central Cuba to the Gulf of Honduras. Scattered moderate convection is noted within 90 nm of this boundary. The monsoon trough extends from the eastern Pacific Ocean across Costa Rica and Panama to the northwest coast of Colombia near 10N75W. Scattered moderate convection is occurring south of 11N with this feature. Additional scattered moderate convection is noted along and offshore of eastern Honduras and Venezuela from 12N to 16N between 82W and 85W. Moderate to fresh NE winds are noted west of the stationary front, in the Gulf of Honduras, and in the central Caribbean, locally strong in the south-central Caribbean. Mainly moderate to locally fresh trades prevail elsewhere. Seas of 4 to 6 ft dominate the basin, locally to 7 ft in the south-central Caribbean. For the forecast, the stationary front will gradually dissipate through Tue. Meanwhile, high pressure will continue to support moderate to fresh trades across most of the basin, pulsing to strong off the coast of Colombia. The ridge will begin to strengthen on Wed leading to increasing winds over the central Caribbean through most of Thu. ATLANTIC OCEAN... A cold front extends from 31N68W to the central Bahamas where the boundary transitions to stationary to central Cuba. Moderate to locally fresh winds are west of the front, with gentle to moderate winds east of the cold front. Seas are mainly 4 to 6 ft in easterly swell west of 65W to the Bahamas, locally to 7 ft. Scattered moderate convection is noted north of 27N within 90 to 180 nm ahead of the front. Farther east, a cold front extends down from 31N24W to 23N39W where it transitions to stationary to 24N48W. Scattered moderate convection is along the front north of 29N, with isolated to scattered showers elsewhere near the front. Fresh to strong winds are noted north of 30N between 32W and 38W, with moderate to fresh winds elsewhere within 60-90 nm behind the front. A 1025 mb high pressure center is just north of the area near 34N44W. Moderate to locally fresh trades dominate the remainder of the basin. Large northerly swell with seas of 8 ft or greater covers the waters north of 11N and east of 65W, with peak seas of 10 to 14 ft north of 27N between 26W and 40W. The Cumbre Vieja volcano, on the island of La Palma in the Canary Islands, has been erupting since 19 September 2021. 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 55W, the cold front will reach from near 28N65W to 25N70W by Tue afternoon, leaving a stationary boundary near 22N into Wed as strong high pressure builds in behind it. The gradient between the high pressure and the stationary front will lead to increasing east winds and building seas south of about 28N from Wed through late Thu. Looking ahead, a cold front will move into the waters off northeast Florida on Fri and reach from near 31N62W to 27N71W to central Cuba By Sat night. This front will be followed by fresh to strong northeast to east winds and building seas north and northeast of the Bahamas. $$ Lewitsky