000 AXNT20 KNHC 281008 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Tue Dec 28 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 low pressure system located over the central Atlantic is producing hurricane force winds N of the forecast area, with gale force winds that extend into the discussion area south of 31N. A cold front associated with the deepening low enters the Atlantic forecast region near 31N40W and extends westward to near 23N60W and then to 25N70W east of the Bahamas. SW winds to gale force are occurring north of 29n and east of the front to 35W. Very large seas are accompanying the front with NW swell. An altimeter satellite pass from around 0830 UTC indicated seas as high as 20 ft along 31N following the front. Scattered showers and thunderstorms are evident within 90 nm east of the front. The front will move southwest through Wed, with gale force winds lifting NE of the area midday today. Seas will subside accordingly, although 8 to 14 ft seas will persist north of 20N and east of 60W through tonight. 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 Sierra Leone near 08N13W to 06N20W. The ITCZ continues from 06N20W to the coast of NE Brazil near 00N47W. No significant convection is evident at this time. ...GULF OF MEXICO... The extension of a ridge that is centered near Abaco Island, Bahamas near 27N77W reaches westward across the Gulf waters. Gentle to moderate SE to S flow and seas of 1-3 ft prevail over the eastern half of the Gulf while moderate to fresh SE to S winds with seas of 3-6 ft are noted over the western half of the Gulf. For the forecast, the ridge extending from the western Atlantic into the Gulf will continue support moderate to fresh winds across the central and western Gulf through Wed. The ridge 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, southeast to south winds are expected to increase over the western Gulf by late Fri as low pressure moves into the Central Plains. A strong cold front associated with this low pressure may reach the Texas coast late Sat night. ...CARIBBEAN SEA... Weak high pressure centered north of the area over the northern Bahamas dominates the pattern across the Caribbean Sea. Earlier scatterometer and altimeter passes confirmed the presence of fresh to strong northeast winds and seas of 7 to 9 ft off the coast of Colombia with moderate to locally fresh trades and 5-7 ft prevalent across the remainder of the south- central Caribbean, including the Windward Passage. Elsewhere, seas of 3-5 ft are noted, with the exception of the far eastern part of the basin where gentle to moderate trades are observed. For the forecast, winds and seas will increase through mid week across the central Caribbean and the Gulf of Honduras as high pressure near the Bahamas builds. ...ATLANTIC OCEAN... Please see the Special Features section above for details about the gale warning in the Atlantic. High pressure is building over the waters west of 65W in the wake of the cold front moving through the region. This is supporting gentle to moderate winds and 3 to 5 ft seas over open waters. Farther east, the Atlantic ridge extends from 1025 mb high pressure over Morocco, southeastward to 20N50W, supporting light to gentle winds along the ridge axis. Moderate to fresh trade winds and seas of 4 to 7 ft prevail across the tropical Atlantic south of the ridge axis. For the forecast west of 65W, the cold front will move southeast of the region through Wed. High pressure currently over the northern Bahamas will shift eastward following the front, and strengthen northeast of the Bahamas through Sat. $$ Christensen