000 AXNT20 KNHC 141650 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Tue Dec 14 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 1645 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Sierra Leone near 07N12W to 05N17W. The ITCZ continues from 05N17W to 06N35W to the coastal border of French Guiana and Brazil near 04N50W. Scattered moderate convection is noted within 150 nm north and 90 nm south of the ITCZ between 20W and 46W. GULF OF MEXICO... High pressure prevails over area with two low pressure troughs in the Bay of Campeche producing isolated moderate convection. Moderate to fresh winds prevail over the southeast Gulf with gentle to moderate winds elsewhere. Seas are 4-6 ft over the southeast Gulf including the Yucatan Channel, 1-3 ft over the northeast Gulf, and 3-5 ft elsewhere. For the forecast, high pressure will prevail across the northern forecast waters through the week. Fresh east winds will spread westward through the Straits of Florida and into the eastern Gulf S of 26N through midweek along with building seas. CARIBBEAN SEA... The pressure gradient from high pressure centered over the southeast U.S. combined with lower pressure over Colombia is supporting fresh to strong easterly winds over the central Caribbean including the Windward Passage, south of Hispaniola, and offshore Colombia. Fresh winds prevail across most of the remainder of the basin. Seas are generally 5 to 7 ft, with a recent altimeter pass finding up to 8 ft in the central Colombian basin. Scattered showers and thunderstorms are noted between 70W- 82W and from 14N-17N as well as along the coasts of Costa Rica and southern Nicaragua. For the forecast, fresh to strong trades will continue over the south-central Caribbean through the week. Moderate to fresh trades will prevail elsewhere. Strong high pressure will prevail over the western Atlantic through the forecast period. This will result in fresh to locally strong northeast to east winds in the Windward Passage, Mona Passage, the lee of Cuba, and south of Hispaniola through the week. ATLANTIC OCEAN... Scattered moderate convection and fresh NE winds associated with a low pressure trough near Florida extend 180 nm from the coast. A cold front extends from 31N51W to 29N56W. Scattered moderate convection is noted within 60 nm of this boundary north of 30N. A 1028 mb Azores high is centered near 37N28W. The pressure gradient between this area of high pressure and lower pressure within the monsoon trough and in the vicinity of the ITCZ is supporting a large area of fresh to locally strong easterly trade winds across the Atlantic from 13N to 24N with 8 to 10 ft seas. North of 24N and west of 35W, gentle to moderate trades prevail with 4 to 7 ft seas. North of 24N and east of 35W, moderate to fresh NE winds prevail with 7 to 9 ft seas. South of 13N, moderate to fresh trades prevail with 7 to 9 ft seas. The Cumbre Vieja volcano, on the island of La Palma in the Canary Islands, has been erupting since 19 September 2021. Feeble ash concentrations are expected near 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, high pressure will prevail across the western Atlantic, supporting moderate to fresh winds over the forecast waters. High pressure will build southward from the middle to end of the week resulting in an increase in winds and seas. This pattern will also increase winds and seas east of 65W through the week. $$ FLYNN