000 AXNT20 KNHC 200001 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Sun Oct 20 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 1800 UTC surface analysis and satellite imagery through 2300 UTC. ...SPECIAL FEATURES... Compact and powerful Oscar is moving very near the Turks and Caicos Islands. Hurricane Oscar is centered near 21.3N 71.6W at 19/0000 UTC or 30 nm WSW of Grand Turk Island, moving W at 9 kt. Estimated minimum central pressure is 987 mb. Maximum sustained wind speed is 75 kt with gusts to 90 kt. Numerous moderate to strong convection is noted mainly on the W semicircle of the hurricane from 20N to 23N between 70W and 72W. Peak seas are around 15 ft. Oscar is moving toward the west, and this motion with a gradual slowdown and turn to the west- southwest is forecast tonight into tomorrow. A sharp turn to the northeast is anticipated by Monday. A little more strengthening is possible tonight, but gradual weakening is expected to begin by Sunday night and Monday. Oscar is a very small hurricane. Oscar is expected to bring hurricane conditions to portions of the Turks and Caicos Islands and the southeastern Bahamas this evening and overnight, and could bring hurricane conditions to eastern Cuba during the next day or two. A Hurricane Warning is in effect for the Turks and Caicos and southeastern Bahamas, and a Hurricane Watch is in effect for portions of eastern Cuba. Locally heavy rainfall is possible across the Turks and Caicos Islands and the southeastern Bahamas later today and tonight. These rains are expected to spread to eastern Cuba on Sunday. Oscar is expected to produce a dangerous storm surge on the Turks and Caicos Islands beginning this evening. Minor coastal flooding is also possible along the north shore of Cuba later on Sunday. Nadine becomes a tropical depression over northern Guatemala. It is centered near 17.3N 90.0W at 19/0000 UTC or 100 nm W of Belize City, moving W at 11 kt. Estimated minimum central pressure is 1006 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. Numerous moderate to isolated strong convection is noted over Belize, northern Guatemala and the Yucatan Peninsula. On the forecast track, Nadine is expected to move across northern Guatemala and southern Mexico through early Sunday. Continued weakening is expected, and Nadine is forecast to dissipate on Sunday. Widespread rainfall amounts of 4 to 8 inches, with isolated areas of 12 inches, are expected across northern Belize, northern Guatemala, and southern Mexican states from Quintana Roo westward to Veracruz and Oaxaca through Tuesday. Localized areas of flash flooding are possible along the track of Nadine across southern Mexico, northern Guatemala, and northern Belize. Minor coastal flooding is possible in areas of onshore winds for a few more hours. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml, the latest NHC Forecasts/Advisories and Public Advisories for Oscar and Nadine at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave is along 31W from 20N southward, moving west at around 10 kt. Scattered moderate convection is noted on either side of the wave axis from 10N to 17N between 27W and 33W. A second tropical wave is moving across the central Caribbean. Its axis extends from Dominican Republic to western Venezuela. Scattered showers, with embedded thunderstorms, are behind the wave axis in a SE wind flow affecting the eastern Caribbean. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic near 17N16W and extends southwestward to 11N27W. The ITCZ runs from 09N34W to 08N55W. Aside for the convection associated with the tropical wave, scattered moderate convection is noted from 05N to 10N between 30W and 45W. ...GULF OF MEXICO... The pressure gradient between tropical cyclone Nadine to the south and strong high pressure over the eastern United States supports fresh to strong NE to E winds across most of the Gulf waters, including the Straits of Florida and the Yucatan Channel. Seas are in general 6 to 9 ft, except 9 to 12 ft over the SE Gulf per latest altimeter data. Seas of 7 to 10 feet, occasionally to 13 feet are expected in the Straits of Florida tonight. Outer bands, with embedded showers and thunderstorms, associated with the cyclonic circulation of Nadine are reaching the northern Yucatan Peninsula and regional waters and the central and eastern portions of Bay of Campeche. For the forecast, Tropical Storm Nadine moved inland on Saturday into Belize, and will weaken to a tropical depression over Guatemala and southern Mexico tonight, then dissipate. It may send some strong winds to the far southeastern Bay of Campeche tonight and early Sunday. Otherwise, fresh to strong NE winds and rough to very rough seas will continue to affect much of the basin through Mon morning as strong high pressure builds over the southeast United States. ...CARIBBEAN SEA... A diffluent pattern aloft is helping to induce convection across Cuba, the Cayman Islands, Jamaica and the NW Caribbean. An outer band of tropical cyclone Nadine is affecting the northern Yucatan Peninsula, including Cozumel and Cancun. Latest satellite derived wind data indicate fresh to strong NE to E winds over the NW Caribbean with seas of 7 to 10 ft. Fresh NE winds are noted in the Windward Passage and near Cabo Beata in Dominican Republic. Moderate to fresh trades and seas in the 4 to 6 ft range dominate the central Caribbean while gentle to moderate easterly winds are seen over the E Caribbean, including the waters between islands in the Lesser Antilles where mainly moderate winds are observed per scatterometer data. Seas are 3 to 5 ft in this area. For the forecast, Hurricane Oscar, currently located north of Hispaniola, may impact the Windward Passage and waters adjacent to eastern Cuba early next week. PLease, see the Special Features section for more information on Nadine and Oscar. ...ATLANTIC OCEAN... Please see the Special Features section for information on Hurricane Oscar. A cold front enters the region near 31N58W and extends SW to western Cuba. A few showers are near and ahead of the front but mainly N of 27N. Fresh to strong NE winds and seas of 8 to 12 ft are noted in the wake of the front. Strong high pressure located over the eastern of United States dominates the waters W of the front and the Florida Peninsula. Aside for Hurricane Oscar, the remainder of the Atlantic forecast waters is under the influence of a ridge, anchored by a 1023 mb high pressure situated in the vicinity of the Madeira Islands. Moderate to locally fresh winds are noted across the tropical Atlantic while mainly gentle to moderate winds prevail N of 20N and E of 60W. In general, seas are 5 to 8 ft with the highest seas NE and N of the Cabo Verde Islands to about 23N, NE of the easternmost Canary Islands, and from 09N to 12N between 38W and 42W. For the forecast west of 55W, Oscar will move to 21.2N 72.6W Sun morning, 21.0N 74.1W Sun afternoon, and 20.9N 74.9W Mon morning. Oscar will weaken to a tropical storm near 21.2N 75.6W Mon afternoon, reach 21.9N 75.3W Tue morning, and 23.3N 74.2W Tue afternoon. Elsewhere, the aforementioned cold front will move eastward north of 25N through Sun, then weaken to a trough through the early part of the week. Fresh to strong winds and rough seas will prevail west of the front through early next week. $$ GR