000 AXNT20 KNHC 180804 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Sun Dec 18 2022 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 0740 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal plains of Liberia near 06N10W to 05N15W. The ITCZ extends from 05N15W to 04N35W to the coast of French Guiana at 05N52W. Scattered moderate isolated strong convection is noted from 03N to 06N between 24W and 49W. GULF OF MEXICO... A cold front extends from near Tampa Bay, Florida to the SW Gulf stalls to the central Bay of Campeche. Earlier ASCAT scatterometer data showed fresh to strong N to NE winds north of the front and west of 87W. Fresh to strong NW to N winds are west of the stationary front offshore Mexico. Seas are 7 to 11 ft north of the front to 26N and west of 91W, and 3 to 6 ft elsewhere north of the front. Weak 1014 mb low pressure is southeast of the front near 25N84W along a trough which extends from SW Florida through the low to the north-central Yucatan Peninsula. Mainly gentle to moderate winds and 2 to 4 ft seas are south of the front. Some showers and thunderstorms are near the low per satellite imagery. Similar convection is noted near the Yucatan Channel southeast of the trough. For the forecast, the cold front will sweep southward across the SE Gulf into the Straits of Florida by tonight while low pressure ahead of it weakens while shifting southeast, except the western portion of the front will move northward over the western Gulf ahead of low pressure moving through northeast Mexico. The front may continue to lift northward early Tue as a warm front while the low pressure moves into the north-central Gulf. A trailing cold front over the western Gulf will dissipate through mid week. Looking ahead, a stronger cold front may move off the Texas coast into the far northwest Gulf Thu night followed by near-gale or gale force winds and building seas. CARIBBEAN SEA... Fresh to strong NE to E tradewinds prevail across the south- central and SW Caribbean Sea due to surface ridging across the Atlantic subtropical waters. Earlier ASCAT scatterometer data showed moderate to locally fresh trade winds in the E basin and gentle to moderate winds in the NW Caribbean. Seas are in the 5 to 7 ft range in the eastern half of the basin, 7 to 10 ft in the south-central and SW Caribbean, and 2 to ft in the north- central and NW Caribbean. Scattered thunderstorms are near and in the Yucatan Channel. Scattered showers are elsewhere in the NW Caribbean west of 85W. For the forecast, surface ridging north of the region will maintain fresh to strong NE to E tradewinds across the central and SW Caribbean Sea through at least Thu night. Moderate to locally fresh winds will prevail in the E Caribbean with gentle to moderate winds in the W Caribbean. Large, long-period N to NE swell will continue to move into the tropical Atlantic and through the Anegada Passage into the northeast Caribbean for the next several days. A cold front will dissipate as it toward the Yucatan Channel tonight into Mon. ATLANTIC OCEAN... A dissipating stationary front extends from 31N56W to near the northern Bahamas and to southern Florida. Fresh to locally strong winds are north of 30N and east of the front to 47W. Scattered showers and thunderstorms are noted north of 26N between 70W and 77W. A ridge axis extends along 25N from 1019 mb high pressure centered near 25N56W. Light to gentle anticyclonic winds are under the ridge north of 22N, except moderate offshore northern Florida where a cold front is moving into the coastal waters. Seas are mainly 4 to 7 ft in NE swell in the SW N Atlantic, except around the eastern periphery where they are 7 to 11 ft. In the eastern and central Atlantic, a cold front extends from southeast of the Azores through 31N26W to 24N35W where it continues as dissipating to 20N46W. Fresh to strong SW winds are north of 27N within 120 nm ahead of the front. Scattered thunderstorms are possible north of 26N within 75 nm ahead of the front per satellite imagery. Large northerly swell of 8 ft or greater dominates the central and eastern Atlantic, peaking around 17 ft along 31N between 26W and 35W, except 5 to 7 ft south and southeast of the Cabo Verde Islands. Moderate to fresh trades dominate the waters south of 20N and west of 35W. For the forecast west of 55W, the dissipating stationary front will completely dissipate today. The cold front off the northeast Florida coast will reach from Bermuda to NW Cuba by late tonight, and from 31N55W to central Cuba Mon night, before starting to weaken from 25N55W to the southeast Bahamas through Tue. Meanwhile, large long-period N to NE swell will continue to affect the NE half of the area for the next several days. Looking ahead, low pressure may move along the front from the eastern Gulf of Mexico across Florida Tue night, then continue to east of the northern Bahamas Wed while dissipating. Winds will become more southerly Thu ahead of a stronger cold front expected to move off the northeast Florida coast by the end of next week. $$ Lewitsky