000 AXNT20 KNHC 151030 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Tue Dec 15 2020 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 32N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0600 UTC surface analysis and satellite imagery through 0850 UTC. ...SPECIAL FEATURES... Gulf of Mexico Developing Gale: Northerly gales behind the current cold front across the Gulf ended this evening, with winds diminishing considerably, and seas slowly subsiding. Another cold front will move into the NW Gulf early tonight and cross the basin Wed through Thursday. Behind the front, brief gales are expected offshore of Veracruz on Wednesday afternoon. Please read the latest High Seas Forecast at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough axis extends from the west coast of Africa near 07.5N13W and continues to 05N20W. The ITCZ begins near 05N20W and continues to 04N35W to the coast of N Brazil near 00N50W. Scattered moderate isolated strong convection is from 02N-09N between Africa and 23W, and from 02N-09N between 24W- 47W. GULF OF MEXICO... A cold front extends from near Venice, Florida to 25N84W. From there, a stationary front continues to 19N93W to the coast of Mexico near 18.5N93.5W. Widely scattered showers are seen over the eastern Bay of Campeche between the front and Progreso, Mexico. Winds has diminished considerably in the past several hours behind the front, with N to NE winds around 15 kt to the northwest of the front across the Bay of Campeche, and NE winds 15 kt across the NE Gulf north of 28.5N. Mainly gentle winds prevail across the remainder of the basin. Seas in the Bay of Campeche and far SW Gulf are still 7-10 ft in north swell and are expected to subside to 6-8 ft by sunrise this morning. Winds and seas will diminish this morning as the front stalls and starts to dissipate from SW Florida to the eastern Bay of Campeche. Another cold front will move into the NW Gulf early tonight and cross the basin Wed through Thu. Brief northerly gales are expected offshore of Veracruz Wed afternoon. Winds and seas will then diminish through Fri as high pressure builds across the northern Gulf in the wake of this front. The next cold front will move into the northwest Gulf by Sat night. CARIBBEAN SEA... A mid to upper level ridge covers the western two-thirds of the Caribbean, leading to subsidence, dry air and mainly fair weather across the entire basin. Weakening high pressure north of the area is supporting gentle to moderate trade winds across the basin. Overnight ASCAT data showed fresh trades confined to the south-central Caribbean, south of the 14N between 70W-78W. Seas of 2-4 ft prevail over the eastern and NW Caribbean, while 4-7 ft seas cover the area from the central to the SW basin. High pressure north of the area will begin to re-strengthen by Wed, and trade winds offshore of Colombia will begin to pulse to strong each night, and then to near gale force Fri and Sat nights. A weakening cold front will move slowly SE across the Yucatan Channel and western Cuba Thu night through Fri before dissipating. Strong high pressure north of the front will produce fresh to strong NE trade winds across much of the area Fri and Sat. ATLANTIC OCEAN... A cold front extends from 32N73W to just south of New Smyrna Beach, Florida to near Venice, Florida. Widely scattered showers are along the front. Fresh winds are noted on both sides of the front north of 28N, with strong northerly winds beginning to cross 31N. A surface ridge extends from a 1025 mb high near 32N39W to 32N55W to a 1018 mb high near 28N66W to the central Bahamas. Gentle anticyclonic winds are within 180 nm either side of the ridge axis. To the south of the ridge, a 1012 mb low is near 23N58W, directing below a deep layered upper level cyclone. Fresh E to SE winds are on the north and east sides of the low and are producing scattered moderate showers and isolated tstorms from 18N-26N between 50W- 57W. A surface trough oriented SSW- NNE extends through the low from 18N to 27N. Upper-level diffluence to the east of the upper low is enhancing this convection. In the NE Atlantic, fresh NE winds extend from the Azores southwestward to 17N and east of 27W. The cold front off NE Florida will sweep eastward across the waters north of 27N through Wed. Meanwhile, the deep layer trough will remain nearly stationary along 57/58W today before drifting westward and weakening tonight through Thu. The next cold front will move into the waters east of northern Florida Wed night then slide slowly SE and reach from near Bermuda through the NW Bahamas to W Cuba Fri morning, then drift southeast of the area through late Sat. Behind the front, expect fresh N winds across the western Atlantic. $$ Stripling