000 AXNT20 KNHC 171059 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1215 UTC Tue Dec 17 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 1030 UTC. ...MONSOON TROUGH/ITCZ... A monsoon trough enters the Atlantic through the coast of Senegal and extends to 14N18W. The ITCZ extends from 06N17W to 05N49W. Widely scattered showers are noted within 120 NM of the ITCZ. ...GULF OF MEXICO... A 1027 mb high pressure is centered over the southeastern United States and ridging extends over the Gulf of Mexico. Moderate to locally fresh E to NE winds are noted over the eastern half of the Gulf of Mexico and into northern portions of the Bay of Campeche. Gentle to moderate E to SE winds prevail over the western Gulf. Seas of 4 to 7 ft are noted in the central basin south of 28N through the Florida Straits and the Yucatan Channel. Seas of 3 to 5 ft are occurring elsewhere. For the forecast, moderate to fresh E to NE winds will prevail this morning in the central and eastern Gulf, with moderate to locally fresh SE winds occurring in the western basin. Thereafter, gentle to moderate winds and slight to moderate seas are expected through Wed. A weakening cold front will enter the northwestern Gulf of Mexico Wed evening, and fresh to strong N to NW winds will occur along and behind the front. The front will weaken and dissipate over the central Gulf by early Thu. Looking ahead, building high pressure over the south-central United States will lead to moderate N to NE winds and slight to moderate seas across the basin Thu through Sat. ...CARIBBEAN SEA... A surface trough has been analyzed from 21N82W to the far northeastern portion of Nicaragua, and a 1009 mb is centered near 09N76W. Moderate NE winds are occurring to the west of the trough in the northwestern Caribbean, where seas of 4 to 7 ft are noted. Elsewhere, moderate to fresh E winds are occurring across central through southeastern portions of the basin, with light to gentle winds occurring in the southwestern Caribbean. Seas of 3 to 6 ft are noted in the aforementioned areas. For the forecast, a strong pressure gradient between high pressure over the northwestern Atlantic and a trough over the western Caribbean will continue to support moderate to locally fresh NE winds across the northwestern Caribbean this morning before winds diminish. The trough will slowly progress northwestward through midweek, and low pressure will strengthen over northwestern Colombia. Moderate to fresh trade winds will occur in response to these features over the central and eastern Caribbean through Fri. Strong NE winds will occur at times off the coast of Colombia and Venezuela, through the Atlantic Passages and in the lee of Hispaniola and Puerto Rico, with the strongest winds occurring at night. Locally rough seas will develop in areas of strong wind. ...ATLANTIC OCEAN... Residual NE swell from recent gale force winds persists across the central Atlantic, maintaining rough seas north of 20.5N. Fresh to strong NE to ENE winds are occurring over this area. Farther east, a cold front extends from 31N36W to 27N47W to 28N57W, with a stationary front continuing to 31N62W. Very rough seas of 12 to 14 ft and fresh to strong NE winds are noted behind the front. For the central Atlantic south of the large NE Swell, moderate ENE to E winds and seas at 8 to 9 ft are evident from 20N to 25N between 35W and 60W. In the Tropical Atlantic from 04N to 20N between 35W and the Lesser Antilles, moderate with locally fresh NE to E winds and 8 to 9 ft seas exist. Gentle to moderate SE winds and seas of 6 to 8 ft in mixed moderate swells prevail for the remainder of the Atlantic Basin west of 35W. For the forecast W of 55W, a tight pressure gradient between strengthening high pressure in the northwestern Atlantic and multiple troughs in the Bahamas and western Caribbean will continue to support widespread fresh E to NE winds and rough seas north of the Greater Antilles through Wed. Large NE swell generated by earlier gale force winds across the northern Atlantic will maintain rough seas across most areas north of the Greater Antilles and Cuba today before seas very slowly subside from north to south late Wed into Thu. Elsewhere, a cold front in the central Atlantic will progress southwestward through Wed, producing fresh to strong winds for areas north of 20N through Thu. Rough seas will accompany the winds, with seas in excess of 8 ft extending as far south as 18N by this evening, as to 14N by Wed morning. South of 20N, moderate to fresh trades and rough seas will prevail through late this week. Looking ahead, the next cold front is forecast to move off the northeastern Florida coast Wed night into Thu, reach from near 32N76W to south-central Florida by late Thu night and stall. A strong cold front may quickly merge with the stalled front late on Fri, followed by fresh to strong NW winds. $$ ADAMS