000 AXNT20 KNHC 300936 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1215 UTC Mon Dec 30 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... Central Atlantic Significant Swell Event: A 996 mb low centered near 30N45W will move northeastward through today, supporting near- gale force winds and rough to very rough seas of 12 to 18 ft covering the waters north of 18N between 30W and 60W. In addition, northerly swell of 8 to 12 ft expands beyond the strong winds and will cover the area north of 14N between 25W and 70W. The low pressure lifts north of the area through Tue, leaving an area of fresh to strong SW and 10 to 13 ft north of 24N between 25W and 45W, and linger 8 to 10 ft swell north of 20N between 20W and 50W. These winds and seas diminish south of 30N through Wed. The large swell may create hazardous rip current conditions for Puerto Rico and other areas in the northern Leeward Islands. Refer to local weather advisories for more information. For more details on the marine conditions, 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 from the coast of Liberia near 06N11W to 05N15W. The ITCZ extends from 05N15W to 02N42W. Scattered moderate convection is active from 03N to 05N between 15W and 25W, and from 02N to 04N between 30W and 40W. ...GULF OF MEXICO... A weak cold front extends from the Florida Big Bend area in the northeast Gulf to southwest Gulf near 24N90W. A few showers and thunderstorms are active ahead of the front over the southeast Gulf. Mostly gentle breezes and 2 to 4 ft prevail across the Gulf at this time. For the forecast, the weak cold front will move slowly to the southeast and weaken and dissipate through Tue. Another cold front will move into the NW Gulf late tonight to early Tue, then move slowly southeast and exit the basin Wed night into early Thu. Moderate to fresh winds and slightly building seas will follow the front through mid week. Looking ahead, another weak front may enter the northern Gulf Fri night. ...CARIBBEAN SEA... Scattered strong convection continues over the northwestern Caribbean off Honduras. Weakening high pressure north of the area is supporting fresh trade winds over the north-central Caribbean where seas are 5 to 7 ft. The pattern supports moderate breezes and 3 to 5 ft elsewhere over the eastern and central Caribbean, and gentle breezes with 1 to 3 ft over the northwest Caribbean. For the forecast, large northerly swell to 10 ft will persist over the Atlantic waters and passages of the Leeward and Windward Islands through Tue, then subside. High pressure centered north of the area will support moderate to fresh trade winds across the eastern and central Caribbean into mid week. The high pressure will build thereafter, following a weak cold front that will move into the Yucatan Channel by late Thu. This pattern will allow fresh to strong winds and occasional rough seas to pulse off Colombia Wed into Fri, and moderate to fresh NE winds elsewhere. ...ATLANTIC OCEAN... Please see the Special Features section for details about the significant swell event in the central Atlantic. The two main features over the northwest Atlantic continue to be the 999 mb low pressure near 30N45W, and 1024 mb high pressure centered to the northwest of the low pressure near 36N63W. The pressure gradient between these features is supporting the strong to near- gale force winds and rough to very rough seas described in the Special Features section, encompassing the area north of 20N between 30W and 65W. Fresh to strong SE winds and seas of 6 to 8 ft are evident off the coast of Florida, driven by the pressure gradient between the aforementioned 1024 mb high and a weak cold front moving through the southeastern United States. Moderate NE to E winds and seas of 6 to 8 ft are noted elsewhere west of 70W within the ridge axis. Gentle to moderate breezes and 4 to 6 ft seas in N swell are noted over the tropical Atlantic south of 20N and west of 35W. Moderate to fresh NE winds and 4 to 6 ft seas are noted east of 35W. Forecast for west of 55W, the deep low pressure system east of the region will support fresh N winds along with large swell today east of 65W. These winds will diminish today as the low moves farther to the northeast, but the swell in excess of 8 ft will persist east of 60W through tonight. Farther west, a weak cold front will move off the northeast Florida coast this morning, then stall and dissipate from roughly 30N75W to the Florida Keys into Tue, ahead of strong cold front expected to move off the northeast Florida coast Tue night. Looking ahead, the second front will reach from Bermuda to central Cuba by late Wed night into Thu morning, then weaken as it reaches from 31N55W to eastern Cuba Fri. $$ Christensen