219 AXNT20 KNHC 270937 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Mon Dec 27 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... ...Atlantic Gale Warning... A deepening storm center located southeast of Nova Scotia continues to move eastward into the central Atlantic. An associated cold front is moving southward between Bermuda and northeast Florida will continue to move southeast and reach a position from 31N45W to 24N60W to 27N83W by late tonight, and from 31N35W to near the Leeward Islands the Turks and Caicos by late Tue. Gale force winds following the front will reach as far south as 29N between 35W and 45W from late this morning through tonight. In addition, large swell in excess of 8 ft will reach as far south as 22N through mid week, with seas as high as 20 ft along 31N today and tonight. Both winds and seas should begin to subside Tue morning as the low pressure lifts out to the northeast. Please read the latest NWS High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more information. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Guinea near 10N14W to 10N20W. The ITCZ extends continues from 05N20W through 03N40W. No significant convection is noted. ...GULF OF MEXICO... 1020 mb high pressure is centered over the eastern Gulf of Mexico off Tampa Bay. Buoy data and a scatterometer satellite pass from 03 UTC indicated fresh SE winds over the northwest Gulf, with 3 to 5 ft seas. Gentle to moderate winds and 1 to 3 ft seas are evident elsewhere. No major showers or thunderstorms are noted across the basin. For the forecast, the high pressure over the eastern Gulf will continue to support moderate to fresh winds across the central and western Gulf through mid week. The high pressure will shift eastward, allowing gentle to moderate winds and slight to moderate seas across the entire basin Thu, as a weak frontal boundary stalls and dissipates along the Texas coast. Looking ahead, SE to S winds may increase over the western Gulf by late Fri as low pressure moves into the central and southern plains. ...CARIBBEAN SEA... A recent scatterometer pass confirmed fresh to strong northeast winds off the coast of Colombia. A concurrent altimeter pass showed seas to 8 ft there as well. A trough extends from the southeast Yucatan Peninsula to eastern Honduras. A pair of ship observations showed fresh SE winds over the northwest Caribbean, south of the Yucatan Channel, between the trough and the high pressure farther north. Elsewhere, 1020 mb high pressure north of the area over the eastern Gulf of Mexico dominates the pattern over the Caribbean Sea generating a moderate to fresh trades mostly across the eastern and central basin, to include the Windward Passage and in the lee of central Cuba. In addition to the 6 to 8 ft off central Colombia, seas are roughly 4 to 6 ft across the basin except for 2 to 4 ft in the northwest Caribbean. Regional radar shows a few showers over the Leeward Islands embedded in the trade wind flow, but no significant shower or thunderstorms activity is evident elsewhere. For the forecast, the high pressure over the eastern Gulf of Mexico will continue to maintain moderate to fresh winds across the Caribbean into Tue, with strong winds pulsing off Colombia mainly at night. The high pressure will move eastward into the western Atlantic and strengthen mid to late week, support fresh to strong winds over parts of the central Caribbean and Gulf of Honduras by mid week. ...ATLANTIC OCEAN... Please read the Special Features section on a Gale Warning issued for the central Atlantic. A trough is analyzed ahead of the aforementioned cold front approaching from the northwest. Scattered showers and thunderstorms are active within 90 nm east of the trough. The cold front reaches as far south as 29N between 55W and 75W, displacing the subtropical ridge southward to a position from north of the Canary Islands across the Atlantic to the southern Bahamas to high pressure over the eastern Gulf. Fresh to near gale force winds are active ahead of the front north of 26N between 35W and 65W, along with seas of 8 to 12 ft. Elsewhere, gentle to moderate winds and 5 to 7 ft seas are noted along the ridge axis, moderate to fresh trade winds and seas to 8 ft south of 12N. For the forecast, the cold front will move southeast of the region through Wed. High pressure currently over the eastern Gulf will shift eastward following the front, and strengthen northeast of the Bahamas Tue through Fri. High pressure near central Florida dominates the western Atlantic. Winds are generally increasing with latitude from a gentle to moderate northeasterly breeze and 3-5 ft seas near the Greater Antilles to a fresh westerly breeze with 8-10 ft seas north of 29N. Seas range 8-10 ft N of 28N and E of 70W, otherwise seas range 3 to 6 ft across the western Atlantic. East of 65W, a strong westerly breeze and greater fetch area are causing higher seas to propagate farther south with altimeter data confirming seas are greater than 10 ft north of 30N while 8 ft seas reach as far south as 25N in the central Atlantic. In the eastern Atlantic, a dying cold front extends from 31N28W to 28N35W where a dying stationary boundary continues to 26N46W. A fresh breeze is noted along the front. Moderate trade winds are noted south of 20N. Gentle winds dominate the remainder of the basin from 20N to 27N with moderate northerly swell. For the forecast, high pressure over the Bahamas will shift slightly west over Florida ahead of a cold front moving into the waters between northeast Florida and Bermuda tonight. The front will continue to move southeast of the region through Wed. The high pressure will shift eastward following the front, and strengthen northeast of the Bahamas Tue through Fri. $$ Christensen