000 AXNT20 KNHC 272034 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0015 UTC Sat Dec 28 2024 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 1800 UTC surface analysis and satellite imagery through 2030 UTC. ...SPECIAL FEATURES... Central Atlantic Gale Warning and Significant Swell Event: Low pressure of 1012 mb is centered near 30N57W, with cold front extending SW to near 24N67W. The low will quickly move eastward and merge with a 1012 mb low pressure that is near 28N52W. The merged low pressure will deepen with northerly winds increasing to near gale to gale- force Sat, roughly north of 26N between 53W and 57W. Seas with these gale winds will build to 10 to 15 ft. The low pressure is forecast to transition to an occluded system and lift northeastward into the north-central Atlantic Sun through Tue. Winds will diminish below gale- force on Sunday, with the swell generated from the gale winds maintaining seas of 12 to 13 ft over the waters north of 20N between 25W and 55W into the middle part of next week. For more details please refer to the latest NWS High Seas Forecast issued by the National Hurricane Center at the website: https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml ...MONSOON TROUGH/ITCZ... The monsoon trough extends off the coast of Africa near 05N03W to 04N05W. The ITCZ continues from 04N05W to 05N40W. Scattered moderate convection is noted from 00N to 08N between 21W and 34W. ...GULF OF MEXICO... A relatively weak pressure is over the basin as a weak as broad ridge stretches southwestward from the eastern United States to the eastern Gulf. Gentle to moderate winds are found over the waters E of 90W, with gentle winds W of 90W. Seas are in the 4-6 ft range over the NE Gulf and 2-4 ft elsewhere. For the forecast, Fresh E to SE winds will develop in the Florida Straits this evening, with moderate to locally fresh SE winds expanding over the eastern Gulf by early Sat. Elsewhere, moderate to locally fresh SE winds will develop across the western Gulf Sat morning ahead of a weakening cold front moving through the south-central United States. The front will enter the northwest Gulf Sat night and weaken as it moves southeastward this weekend before dissipating over the central Gulf early next week. Looking ahead, another cold front will enter the basin next Tue and move into the central Gulf through midweek. ...CARIBBEAN SEA... Gentle to moderate winds prevail over much of the Caribbean, except over the NW Caribbean where gentle winds prevail. Seas are in the 4-6 ft range over much of the Caribbean, except the NW Caribbean where seas are in the 3-4 ft range. For the forecast, moderate to locally fresh trade winds will prevail across central and eastern portions of the basin this weekend. The strengthening pressure gradient between a building ridge in the western Atlantic, strengthening low pressure in the central Atlantic and low pressure in the south-central Caribbean will promote locally strong NE winds through the Windward Passage and south of Hispaniola tonight through Sun morning. These winds will diminish early next week. Looking ahead, building high pressure north of the area will support increasing winds and seas across the basin by the middle of next week. ...ATLANTIC OCEAN... Please see the Special Features section for details about an upcoming gale event that is forecast to begin on Sat afternoon. A 1012 mb low is centered near 30N57W, with cold front extending SW to near 24N67W. Fresh to strong winds, and seas of 8-10 ft are west of the front to near 68W. Moderate to fresh winds are over the remainder of the waters W of 60W, with seas of 5-8 ft. A stationary front extends over the waters from 31N37W yo 25N44W. Moderate to fresh winds, and seas of 7 ft, are within 120 nm east of the front. Gentle to moderate winds, and seas of 5-7 ft, prevail over the remainder of the discussion waters. For the forecast west of 55W, the low will strengthen and move eastward this weekend. A wide swath of fresh to strong N to NW winds will occur surrounding the low, with these winds occurring north of 25N between 55W and 68W by this evening, and north of 21N between 55W and 65W by Sat morning. Gale force winds are expected Sat afternoon into very early Sun north of 27N near 55W. Rough seas will accompany this system, and seas in excess of 12 ft will occur near the strong winds. These winds and seas will shift east of 55W through late Mon as the low pressure drifts eastward. Elsewhere, moderate to locally fresh E to NE winds will prevail north of the Greater Antilles and west of the low pressure system this weekend, along the periphery of high pressure moving off the coast of the United States. Looking ahead, expect increasing S to SE winds and building seas off northeast Florida late Sat through Sun night ahead of cold front approaching the region over the southeastern United States. $$ AL