000 AXNT20 KNHC 042221 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Sun Dec 5 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 the African continent. The ITCZ extends west-southwestward from 07N14W to 02N39W. Scattered moderate convection is noted from 02N to 09N between 15W and 36W. GULF OF MEXICO... A weak surface trough is supporting isolated showers over the central Gulf. Otherwise, a surface ridge extends westward over the basin from a 1022 mb high over N Florida. The ridge is causing a weak pressure pattern across the entire Gulf, with mainly gentle winds noted across the basin. Seas of 1 to 2 ft prevail across the Gulf of Mexico. For the forecast, high pressure across the northern Gulf will shift slowly ESE across the basin by Sun. Tranquil conditions are expected to continue through the rest of the weekend. A weak cold front is expected to briefly enter the NW Gulf late Mon with moderate to locally fresh northerly winds behind it. The front could linger through Tue night with gentle to moderate winds along it. The next front is expected to enter the NW Gulf Wed and stall through Thu. CARIBBEAN SEA... Mid-level ridging prevails across the Caribbean Sea, leading to subsidence and relatively dry air, especially east of 75W. Convergent trade winds are producing scattered showers and thunderstorms over the W central basin near the Honduras coastline, and scattered showers across Jamaica. Convergent surface winds N of the E Pacific monsoon trough are generating scattered showers and isolated thunderstorms over the SW Caribbean, including Panama and W Colombia. Strong ENE trades with 8 to 9 ft seas continue over the south-central Caribbean off the coast of Colombia. Fresh trades and 5 to 7 ft seas prevail elsewhere across the central Caribbean. Fresh trades are also occurring in the Windward Passage and in the Lee of Cuba. Moderate winds and 3 to 5 ft seas prevail elsewhere across the Caribbean. For the forecast, high pressure near Bermuda will maintain fresh NE to E winds across the Caribbean into next week. Strong winds off the coast of Colombia and in the Gulf of Venezuela will pulse to near gale force at night. Winds will pulse to strong at night south of Hispaniola. NE winds will also pulse to strong near the Windward Passage tonight. Active weather across the western Caribbean will end by Sun night. ATLANTIC OCEAN... A surface ridge extends from a 1023 mb high pressure near Bermuda to a 1022 mb high pressure over the northern Florida peninsula. Gentle anticyclonic winds prevail between Florida and Bermuda. Moderate to fresh NE to E trades are occurring farther south, through the southeastern and central Bahamas. Seas are 2 to 5 ft west of 70W and 4 to 6 ft between 65W-70W. A surface trough extends southwestward from a 1018 mb low near 31N54W to 24N59W to 20N59W. Scattered moderate convection is occurring north of 26N between 46W-55W. Fresh winds and 6 to 7 ft seas are in this area. Three surface troughs embedded within the ENE trades are causing isolated to scattered showers from the Equator to 10N between 42W and 55W. A strong 1034 mb high pressure centered over the Azores is dominating the E central Atlantic with fresh trades and seas of 7 to 9 ft N of 10N between the African coast and 45W. Similar winds and seas prevail from 10N to 20N between 45W-60W. Moderate winds and seas of 5 to 7 ft prevail for the remainder of the basin. 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/. The latest advisory states that ash concentration near the volcano is low at this time. For the forecast west of 65W, the weak high pressure ridge extending from Bermuda to the NE Gulf of Mexico will slowly build south and east into the area through Mon. This will support generally tranquil conditions north of 23N for the next several days. Fresh trades will continue north of Hispaniola through the southeastern Bahamas. Moderate to fresh S to SW winds are expected offshore of the N Florida waters Wed and will become light to moderate by Thu. Fresh to strong NE winds and seas of 8 to 10 ft will continue over the NE Atlantic, north of 25N and east of 35W, including near the Canary Islands, for the next few days. $$ Hagen