991 AXNT20 KNHC 272223 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Sun Nov 28 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 2200 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough remains over land. The ITCZ extends from 08N13W to 01N50W. Scattered moderate convection is noted from 01N to 09N between 15W and 40W. GULF OF MEXICO... A 1017 mb surface low is centered near 25N96W. A stationary front is associated to this low, which extends from 24N80W to the low. A surface trough extends from 28N97W to the low to 20N95W. Fresh to locally strong NW to N winds and 5 to 8 ft seas are ongoing over the far western Gulf, west of 95W and along the Mexican coast. Moderate N to NE winds and 3 to 5 ft seas are noted north of the front, with light to gentle N winds and slight seas south of the front. Clouds with embedded showers are increasing over the northwestern Gulf near the low/trough. For the forecast, the low and front will remain nearly stationary tonight before a reinforcing cold front moves into the NW Gulf Sun and moves SE across the basin, pushing the weakening low SE across the central Gulf. The front will sink into the NW Caribbean and exit the basin Mon night through Tue. High pressure will prevail across the basin Tue through Thu. CARIBBEAN SEA... A surface trough extends across the Anegada Passage from 20N63W to 17N64W with no significant convection at this time. Scattered showers and isolated thunderstorms are active off Panama S of 11N, associated to the monsoon trough. No significant convection is noted elsewhere. Seas to 9 ft were observed over the Atlantic waters east of the Leeward Islands by a recent altimeter pass. This is due to continued northerly swell moving into the region. Seas of 5 to 6 ft are across the Atlantic Passages in the northeast Caribbean with 3 to 5 ft elsewhere, except in the Lee of Cuba and Atlantic Coast of Nicaragua and Costa Rica, where 2 ft or less are noted. For the forecast, moderate to fresh NE to E winds will persist over all but the NW Caribbean through Mon. Moderate N to NE swell will continue across the Atlantic waters east of 70W and through the NE Caribbean passages through late Sun. Looking ahead, a weak cold front will move into the northwest Caribbean Mon night, then stall and dissipate Tue night through Wed. High pressure N of the front will induce strong trade winds across the S central Caribbean Tue night through Thu night. ATLANTIC OCEAN... A cold front extends from 31N65W to 24N80W. Moderate NW winds are evident in recent scatterometer data behind the front mainly north 28N. Ahead of the front, scatterometer data indicated mostly fresh southerly winds N of 30N and near 60W. Buoy and altimeter satellite data showed 7 to 9 ft seas north of 28N, likely in a mix of NE and NW swell. Light to gentle winds and 5 to 7 ft seas in NE swell are noted elsewhere over open waters west of 65W. Farther east, scatterometer data indicates a wind shift associated with a weakening stationary front over the central Atlantic that extends from 31N48W to 20N55W. Seas of 8 to 12 ft seas in N swell are noted over much of the area north of 22N between 35W and 60W, with gentle to moderate winds elsewhere. A strong high pressure prevails across the Atlantic waters E of 48W. The Cumbre Vieja volcano, on the island of La Palma in the Canary Islands, has been erupting since 19 September 2021. Low to medium ash concentration is possible near the volcano and is drifting southwestward to the west of Hierro Island. 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 will stall and dissipate from 28N65W to northwest Cuba late Sun into early Mon. A reinforcing cold front will move off NE Florida late Sun, then reach from Bermuda to NW Cuba by late Mon, then start to stall from 27N65W to central Cuba Tue through Wed. Meanwhile, northerly swell will continue to move through the waters E of the Bahamas into early next week, then subside Mon night through Tue. $$ ERA