000 AXNT20 KNHC 271742 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 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 1200 UTC surface analysis and satellite imagery through 1700 UTC. ...SPECIAL FEATURES... ...Atlantic Gale Warning... A deepening low pressure system located over the central Atlantic is forecast to produce hurricane force winds N of the forecast area, and gale force winds S of 31N. The associated cold front enters the Atlantic forecast region near 31N50W and extends westward to near 29N74W. The front will move SE through Wed. A surface trough is ahead of the front and stretches from 31N46W to 27N50W to 24N58W. Scattered showers and thunderstorms are ahead of the trough axis N of 27N. Recent scatterometer data indicate fresh to strong winds covering the waters N of 26N between 38W and 58W. Gale force winds following the front will reach as far south as 30N between 42W and 58W early this afternoon through early Tue morning. 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 Liberia near 06N11W to 05N16W. The ITCZ continues from 05N16W to 04N30W to 02N40W to the coast of Brazil near 03N51W. Scattered moderate convection is within about 60 nm S of the ITCZ between 17W and 21W. Similar convection is noted from 03N to 04N between 09W and 11W. ...GULF OF MEXICO... High pressure of 1021 mb located over Florida near Lake Okeechobee extends a ridge across the Gulf waters producing mainly gentle to moderate anticyclonic flow and seas of 1-3 ft over the eastern half of the Gulf, and moderate to fresh southerly winds with seas in the 3-5 ft range over the western half of the Gulf. Patches of low level clouds are noted but mainly over the NW Gulf. For the forecast, the high pressure will support moderate to fresh winds across the central and western Gulf through mid week. This system will shift eastward, allowing gentle to moderate winds and slight to moderate seas across the entire basin on Thu as a weak frontal boundary stalls and dissipates along the Texas coast. Looking ahead, southeast to south winds may increase over the western Gulf by late Fri as low pressure moves into the Central Plains. ...CARIBBEAN SEA... High pressure located over Florida dominates the pattern over the Caribbean Sea. A recent scatterometer pass confirmed the presence of fresh to strong northeast winds off the coast of Colombia, and just S of Cabo Beata, Dominican Republic. Moderate to locally fresh trades prevail elsewhere. Seas are 7-9 ft off the coast of Colombia and 5-7 ft across the remainder of the south-central Caribbean. Seas of 3-5 ft are noted elsewhere, except in the far eastern part of the basin. A trough is over the northern Leeward Islands and extends from 20N60W to 16N63W. Patches of low level clouds with possible showers are along the trough axis. Similar cloudiness, carried by the trade wind flow, is observed over parts of Central America. For the forecast, high pressure over Florida will 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 by mid to late week, supporting fresh to strong winds over parts of the central Caribbean and Gulf of Honduras by mid week. ...ATLANTIC OCEAN... A cold front enters the Atlantic forecast region near 31N50W and extends westward to near 29N74W. The front will move SE through Wed. A surface trough is ahead of the front and stretches from 31N46W to 27N50W to 24N58W. A Gale Warning is in effect over the central Atlantic in association with these features. Please read the Special Features section for more details. High pressure over central Florida dominates the western Atlantic. Mainly gentle westerly winds are observed off the Florida Peninsula to about 77W per satellite derived wind data with gentle to moderate NE-E winds across the Straits of Florida. Seas are 1 to 3 ft in this area. High pressure of 1023 mb situated near the coast of Morocco dominates the eastern Atlantic, producing light to gentle winds along the ridge axis that extends to near 22N35W. For the forecast W of 65W, a cold front along 27N east of 74W will move southeast of the region through Wed. High pressure currently over Florida will shift eastward following the front, and strengthen northeast of the Bahamas Tue through Fri. $$ GR