745 AXNT20 KNHC 210427 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Thu Dec 21 2023 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 0000 UTC surface analysis and satellite imagery through 0355 UTC. ...SPECIAL FEATURES... Atlantic Ocean Significant Swell Event: A cold front extends from 31N61W to Hispaniola. A 1032 mb high pressure is present in the eastern United States and a 1050 mb high pressure is centered near 45N25W. The strong pressure gradient due to these systems result in fresh to strong northerly winds west of the front and fresh to strong southerly winds east of the front to 48W and north of 25N. Rough to very rough seas prevail in these waters, peaking around 15 ft near 30N65W. The ridge will slide eastward and weaken during the next few days. The wind speeds will decrease and the sea heights will subside to less than 12 ft by Fri. Please read the latest NWS High Seas Forecasts, and the Offshore Waters Forecasts, that are issued by the National Hurricane Center, at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml, and www.nhc.noaa.gov/marine/offshores.php, for more details about the Very Rough Seas. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from 04N09W to 03N08W. The ITCZ continues from 03N08W to 02N30W. No significant convection is noted at this time. ...GULF OF MEXICO... A robust ridge over the eastern United States sustains moderate to locally strong easterly winds east of 89W. Seas in these waters are 5-8 ft. The strongest winds and highest seas are found in the Florida Straits and off NW Cuba. Moderate or weaker winds and slight to moderate seas prevail elsewhere. No deep convection is observed across the Gulf of Mexico. For the forecast, winds and seas will diminish through early next week as the high pressure shifts east, ahead of an approaching cold front. The cold front will move off the Texas coast Sun night, and reach from near Apalachicola, Florida to near Poza Rica, Mexico by Mon night. ...CARIBBEAN SEA... A stationary front stretches from southern Haiti to the border of Colombia and Panama near 08.5N77.5W. A few showers are noted within 90 nm on both sides of front from 12N to 16N. No deep convection is noted in the rest of the Caribbean Sea. The pressure gradient between the strong ridge north of the islands and the stationary front support fresh to strong N-NE winds north of 16N. Seas in these waters are 6-9 ft. The strongest winds and highest seas are occurring in the lee of Cuba and Windward Passage. Fresh to strong easterly winds are evident off southern Hispaniola and off NW Colombia. Seas are 5-8 ft in the areas described. Moderate or weaker winds and moderate seas are prevalent in the rest of the Caribbean. For the forecast, the aforementioned front will dissipate Thu. Building high pressure north of the area will bring a return to more typical E trade winds Fri through early next week. ...ATLANTIC OCEAN... Please, read the SPECIAL FEATURES section above for details about the Central Atlantic Ocean Significant Swell Event. A cold front enters the tropical Atlantic near 31N61W and continues southwestward to northern Hispaniola. A pre-frontal trough is evident ahead of the front, anchored by a 1009 mb low pressure system near 24N59W. Scattered showers and isolated thunderstorms are seen north of 24N and between 55W and 59W. More information on these features can be found in the Special Features section. An upper level low in the central Atlantic is enhancing the development of isolated showers from 17N to 26N and between 37W and 50W. The rest of the Atlantic is dominated by broad ridging. The pressure gradient between the 1050 mb high pressure system near 45N25W and lower pressures in the deep tropics result in fresh to strong easterly winds east of 40W. Seas in these waters are 9-13 ft with the highest seas occurring near 22N29W. Elsewhere, moderate or weaker winds and moderate seas prevail. For the forecast, the aforementioned front will shift east of region by late Fri, except for the southern portion of the front stalling across the northern Leeward Islands. Fresh to strong N to NE winds following the front will diminish through Thu night. Northerly swell will linger into Sun. Looking ahead, winds and seas will increase Sun night and Mon from the central Bahamas to northeast Florida ahead of a cold front approaching from the west. $$ Delgado