000 AXNT20 KNHC 272347 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Thu Nov 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 2300 UTC. ...SPECIAL FEATURES... Significant Swell Event: Long-period NW swell producing seas of 12 to 15 ft, with period of 13 to 15 seconds, is propagating through the north-central Atlantic subtropical waters in the wake of an old frontal boundary that extends from 31N30W to 28N40W to 27N50W. The highest seas currently dominate the waters N of 26N between 27W and 45W. Rough seas extend as far south as 15N and as far west as 58W. The swell set will continue to shift eastward and gradually subside through Thu. Please read the latest high seas forecast that was issued by the National Hurricane Center, at the website- https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml, for details. ...MONSOON TROUGH/ITCZ... The monsoon trough axis enters the Atlantic from the coast of Sierra Leone near 09N13W and continues to 07N20W. The ITCZ extends from 07N20W to 04N35W to 05N52W. Scattered moderate convection is noted from 02N to 06N between 32W and 45W. ...GULF OF MEXICO... A 1010 mb low has been analyzed inland near 27N99W, and a trough extends through the Bay of Campeche. This pattern is supporting fresh S to SW winds and moderate seas over the northwestern and western Gulf of Mexico. Elsewhere, high pressure dominates the Gulf, leading to gentle to moderate winds and slight seas across the remainder of the basin. For the forecast, a cold front is forecast to enter the NW Gulf waters Thu morning. Moderate to fresh S winds are expected over the western Gulf tonight ahead of this front. The front will shift across the Gulf waters before moving SE of the basin this weekend. Fresh to strong N to NE winds and building seas will follow this front. Gusty winds with occasional gusts to gale force may occur over the west-central and SW Gulf W of the front on Fri. High pressure building in the wake of the front will shift E through Sun night as a trough develops in the far western Gulf. The resulting pressure gradient will support fresh to strong E winds and building seas over the waters W of 90W by early next week. ...CARIBBEAN SEA... A plume of deep, tropical moisture ahead of a mid to upper-level trough that stretches from the Bahamas to Cuba and to Honduras is helping to sustain a large area of showers and thunderstorms over the central Caribbean. This convective activity extends from La Guajira Peninsula in Colombia northward to southern Hispaniola. This activity is accompanied by frequent lightning, heavy rain likely reducing visibility at times and gusty winds. A 1007 mb low pressure is analyzed near 15N75W. The eastern portion of the E Pacific monsoon trough extends from northern Costa Rica to northern Colombia. Scattered showers, with embedded thunderstorms, are near the trough axis. The pressure gradient between the aforementioned low and higher pressure over the western Atlantic is generally supporting moderate trade winds across much of the basin, with fresh winds occurring across the northwest Caribbean between Cuba and Honduras. Seas range from 3 to 5 ft, except for slightly higher seas of 5 to 7 ft between the Cayman Islands and NE Honduras. For the forecast, moderate to fresh trades are expected over most of the basin through Sat night, except for locally strong NE winds in the lee of eastern Cuba through early tonight. A cold front will move into the NW Caribbean this weekend, with winds strengthening over these waters in the wake of the front toward the end of the weekend. A large area of numerous thunderstorms accompanied by frequent lightning and heavy rain will reduce visibility and produce locally gusty winds and higher seas over portions of the central Caribbean tonight. ...ATLANTIC OCEAN... Please refer to the Special Features section for details about the ongoing long-period swell event affecting a portion of the north-central Atlantic waters. A surface trough is analyzed from near 26N73W to the Windward Passage. Moderate to locally fresh E to NE winds are noted surrounding the trough, particularly from 21N to 25N between 70W and 78W. Moderate to locally strong convection is also occurring in this region. To the north and east of the trough, ridging dominates the central waters. Farther east, the aforementioned old frontal boundary extends from near 31N30W to 28N40W and to 27N50W, and a trough has be analyzed to the south and east. Moderate to locally fresh trades exist farther south over the tropical Atlantic, where 5 to 8 ft seas persist. Elsewhere, gentle to moderate winds exist near a surface trough crossing the Canary Islands. Seas 6 to 7 ft in N swell are reaching these islands. Seas of 8 to 11 ft also in N swell dominate the waters N of 14N between 21W and 58W. Elsewhere, gentle to moderate winds and moderate seas prevail. A broad moisture plume is streaming north-northeastward from the central Caribbean Sea to across the Atlantic waters between 50W and 73W. Scattered showers along with small patches of light to moderate rain are underneath these clouds. An area of scattered showers and isolated thunderstorms is approaching the Lesser Antilles. For the forecast, high pressure prevails over the northern waters while a surface trough is near 26N73W to the Windward Passage. The trough will move westward, reaching the NW Bahamas and central Cuba late on Thu before weakening. A cold front is expected to move into the NW part of the area Thu night into Fri. The front is forecast to move across the waters through the weekend before becoming stationary from near 31N59W to central Cuba on Sun. Moderate to fresh winds and moderate seas will follow the front. A reinforcing front may move off the Florida coast early Sun, and merge with the stationary front Monday. $$ ADAMS