000 AXNT20 KNHC 301747 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1815 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 1200 UTC surface analysis and satellite imagery through 1800 UTC. ...SPECIAL FEATURES... Central Atlantic Significant Swell Event: A 997 mb low centered near 31N44W will move northeastward through today, supporting near-gale force winds and rough to very rough seas of 12 to 15 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 15N between 25W and 65W. The low pressure lifts north of the area through Tue, leaving an area of fresh to strong SW winds and 10 to 13 ft seas north of 21N between 25W and 45W, and lingering 8 to 10 ft swell north of 20N between 20W and 50W. These winds and seas diminish south of 31N 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 05N08W and continues to 04N13W. The ITCZ then continues from 04N13W to 00N48W. Scattered moderate and isolated strong convection are observed from the Equator to 06N between 25W and 42W. ...GULF OF MEXICO... A weak cold front extends from near Tampa Bay to about 26N87W, with a few showers in the vicinity of the front. Across the far western Gulf W of 95W, moderate to fresh S winds are occurring due to a deepening low over the central US. Otherwise, mostly gentle breezes and slight seas prevail across the Gulf at this time. For the forecast, a weak cold front extending from the Tampa Bay area to the central Gulf will move slowly to the southeast while weakening and dissipate late tonight into early 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 showers and isolated thunderstorms continue over the northwestern Caribbean generally north of 15N between 80W and the Yucatan Peninsula. Weakening high pressure north of the area is supporting moderate to fresh E winds and seas of 4-7 ft across much of the central and eastern Caribbean, with gentle to moderate E winds and seas of 3-5 ft in the NW 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 early Tue, then subside. High pressure centered north of the area will support moderate to fresh trade winds across the eastern and central Caribbean through Fri night, reaching strong speeds at night off Colombia Wed and Thu. The tail of a cold front will move into the Yucatan Channel by late Thu and dissipate early Fri. The passage of this front N of the area will support the development of moderate to fresh NE winds in the NW Caribbean through Fri night, including the Windward Passage. ...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 997 mb low pressure near 31N44W, and 1022 mb high pressure centered to the northwest of the low pressure near 35N63W. An expansive cold front associated with the low runs from 31N37W to 20N42W to 12N61W, with a pre-frontal trough roughly 75-100 nm ahead of and paralleling the front. Convergence between these features and another 1031 mb high in the NE Atlantic is leading to scattered moderate convection north of 20N between 25W and 40W. The pressure gradient between the aforementioned 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 SE winds and seas of 5 to 7 ft are evident north of 29N between 70W and 77W, driven by the pressure gradient between the aforementioned 1024 mb high and a weak cold front moving off the southeastern US coast. Moderate NE to E winds and seas of 4 to 7 ft are noted elsewhere west of 70W within the ridge axis stemming from the 1022 mb high. Across the remainder of the Atlantic, scattered showers and isolated thunderstorms are occurring from 06N to 12N between 26W and 46W. Gentle to moderate breezes and 4 to 7 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, moderate to fresh NNE winds along with large swell east of 60W associated with a deep low pressure system east of the region will diminish today as the low moves farther to the NE. However, swell in excess of 8 ft will persist east of 60W through tonight. A weak cold front over the NE Florida offshore waters will stall and dissipate from roughly 30N75W to South Florida tonight into early Tue. A stronger cold front is expected to move off the NE Florida coast Tue night, reach from Bermuda to central Cuba by late Wed night into Thu morning, and weaken as it reaches from 31N55W to eastern Cuba Fri. $$ Adams