000 AXNT20 KNHC 080415 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Thu Dec 8 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 0000 UTC surface analysis and satellite imagery through 0400 UTC. ...SPECIAL FEATURES... Central Atlantic Storm Warning: A large, storm-force low pressure system is centered near 29N53W, or about 640 nm ESE of Bermuda. The central pressure is 980 mb. The maximum winds of 50-55 kt are located in the NW quadrant. The gales extend outward up to 450 nm from the center in the N semicircle, 330 nm SE quadrant and 450 nm SW quadrant. Winds of 25 kt or higher associated with the low are currently occurring north of 20N between 40W and 67W. Seas 12 ft or greater are occurring north of 20N between 43W and 68W. Seas 8 ft or greater are occurring everywhere north of 17N between 35W-74W. The estimated maximum seas of 35 ft are occurring in the NW quadrant near 30N 56W. An occluded front extends E from the low pressure to 29N38W. Scattered moderate convection is observed within 210 nm of the front. Although this system may acquire some subtropical characteristics tonight and Thursday, it is unlikely to become completely detached from a frontal zone. By Friday, the low will move northeastward over cooler waters and interact with a mid-latitude trough, limiting the chance for additional subtropical or tropical development of the system. Regardless of development, winds on the northern and western portions of this low will remain storm force through Thu afternoon. Gales will then continue in the central Atlantic through Fri. Overall, there is a medium chance of subtropical or tropical development within the next 48 hours. More information about this system, including the associated storm warning, can be found in the High Seas Forecasts issued by the National Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the Offshore Zone Forecasts at https://www.nhc.noaa.gov/text/MIAOFFNT3.shtml ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Sierra Leone near 08N13W to 07N17W. The ITCZ continues from 07N17W to 05N46W. Scattered moderate convection is observed from 02N to 08N, between 30W and 43W. GULF OF MEXICO... A 1026 mb surface high pressure is centered near the Florida Panhandle, causing gentle winds and 1-3 ft seas in the NE Gulf. This feature is also supporting areas of dense fog in the northern Gulf that will linger through Thu morning. In the southern Gulf, easterly winds are moderate to fresh with 3-5 ft seas. In the western Gulf, SE winds are moderate with 2-4 ft seas. For the forecast, the high pressure system will meander about the area through the forecast period. Gentle to moderate mainly SE winds will prevail through Mon night. CARIBBEAN SEA... The pressure gradient between subtropical high pressure in the western Atlantic and lower pressure over Colombia is generating fresh to locally strong NE winds in the central and western Caribbean Sea, including the Windward Passage. In the E Caribbean, gentle to moderate N winds prevail. Seas in the central and W Caribbean are 5-7 ft and seas in the E Caribbean 3-4 ft except 5-8 ft of N swell through the Mona and Anegada Passages. For the forecast, a strong low pressure system currently over the central Atlantic will continue to deepen during the next few days, maintaining NE-E winds across much of the forecast waters. Fresh to pulsing strong NE winds will affect the Caribbean Passages, the lees of the Greater Antilles, and offshore Colombia through Fri. Large NE swell across the central Atlantic will move through the Caribbean Passages and Tropical Atlantic waters through Sat. ATLANTIC OCEAN... Please read the Special Features section above for details on a storm force low pressure system, affecting the waters north of 18N between 35W and 75W. Elsewhere, a weak pressure pattern prevails off central and northern Florida, with gentle winds and 4-6 ft seas in the far western Atlantic. In the eastern Atlantic, a cold front extends from 31N13W to 24N24W. North of the front, moderate WNW winds and 8-12 ft seas dominate. South of the front, a 1015 mb high pressure center is analyzed near 19N32W, causing light to gentle winds and 5-8 ft seas. For the forecast W of 55W, large long-period north to northeast swell will impact the Atlantic waters and Caribbean Passages between the southeastern Bahamas and the E Caribbean producing high seas through the weekend, with large E swell reaching the Florida offshore waters N of 26N early Fri through Sat. $$ Flynn