000 AXNT20 KNHC 241002 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Tue Sep 24 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 0900 UTC. ...SPECIAL FEATURES... Potential Tropical Cyclone Nine is centered near 18.9N 83.0W at 24/0900 UTC or 100 nm WSW of Grand Cayman, moving NW at 7 kt. Estimated minimum central pressure is 1001 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. Seas are 8 to 11 ft in an area from 17N to 21N between 79W and 84W. Numerous moderate to scattered strong convection is noted from 12N to 22N between 77W and 85W. Nine is expected to become a tropical depression today, then strengthen into a tropical storm tonight. Additional strengthening is forecast over the next several days, and Nine is likely to become a hurricane Wednesday. Nine may become a major hurricane Thursday, before landfall Thursday night in Florida. Potential Tropical Cyclone Nine is expected to produce rainfall amounts of 4 to 8 inches over western Cuba and the Cayman Islands, with isolated amounts in excess of 12 inches. Over the eastern Yucatan Peninsula, 2 to 4 inches of rain is expected with localized amounts over 6 inches. These rainfall amounts bring a risk of considerable flooding. For the southeastern U.S. rainfall accumulations of 3 to 6 inches are forecast, with some totals over 10 inches possible. This will likely result in locally significant flash and urban flooding, with river flooding also possible. The combination of a dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. It is recommended that residents in the aforementioned areas stay alert on the latest information from their local meteorological agencies. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest Nine NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...TROPICAL WAVES... An eastern Atlantic tropical wave is near 26N south of 19N, now moving W of the Cabo Verde Islands at around 10 kt. Scattered moderate to isolated strong convection has increased and become a bit more concentrated overnight from 12N to 17N between 22N and 27W. Fresh to locally strong E winds accompany this wave, with seas of 6 to 8 ft. Environmental conditions appear favorable for gradual development of this system, and a tropical depression is likely to form in a few days while the wave moves W to WNW across the eastern and central Tropical Atlantic. There is a low chance of tropical formation in the next 48 hours and a high chance of formation within the next seven days. A western Atlantic tropical wave is along 50W, south of 17N, moving W at around 10 kt. A broad area of scattered, disorganized, moderate convection associated with this wave extends from 09N to 17N between 44W and 58W. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic near 17N16W, then curves southwestward to near 08N35W. The ITCZ extends from 07N38W to 09N46W. Convection in the vicinity of these features is primarily associated with the two tropical waves described in the section above. ...GULF OF MEXICO... Please refer to the Special Features section above for details on Potential Tropical Cyclone Nine. Moderate E winds are gradually increasing in the far SE Gulf of Mexico, including the Florida Straits and Yucatan Channel, in association with Nine. Weak high pressure of 1013 mb offshore the Florida Panhandle is dominating the rest of the basin, supporting light to gentle mainly E winds and slight seas. A surface trough that moved W off the Yucatan Peninsula overnight is leading to little sensible weather over the SW Gulf. For the forecast, Potential Tropical Cyclone Nine will move to 19.6N 84.2W this afternoon, 20.7N 85.7W Wed morning, 22.0N 86.2W Wed afternoon, and 24.3N 85.6W Thu morning. Nine is expected to become a large and powerful hurricane. Widespread showers and thunderstorms will shift into the area as Nine moves northward into the eastern Gulf late this week. ...CARIBBEAN SEA... Please refer to the Special Features section above for details on Potential Tropical Cyclone Nine. Away from Nine, moderate to locally fresh E tradewinds and slight to moderate seas dominate much of the basin. For the forecast, Potential Tropical Cyclone Nine will move to 19.6N 84.2W this afternoon, 20.7N 85.7W Wed morning, 22.0N 86.2W Wed afternoon, and 24.3N 85.6W Thu morning. Widespread showers and thunderstorms will continue across the W and NW Caribbean through Wed as Nine moves through and then exits the region. ...ATLANTIC OCEAN... See the tropical waves section for information on a wave in the far eastern Atlantic that has potential for tropical development this week. A weak surface trough extends from 31N60W to 25N72W. Convection associated with this trough has diminished overnight. Moderate to fresh E to NE winds are noted across much of the Atlantic east of 40W and north of the monsoon trough. Elsewhere, gentle to moderate winds prevail. Seas are generally 3 to 6 ft, with some 6 to 8 ft seas in N swell following the surface trough between Bermuda and the Bahamas. For the forecast W of 55W, Potential Tropical Cyclone Nine will move to 19.6N 84.2W this afternoon, 20.7N 85.7W Wed morning, 22.0N 86.2W Wed afternoon, and 24.3N 85.6W Thu morning. Nine will bring strong winds and large seas to areas offshore Florida and N of the Bahamas late this week. Tropical storm force winds are expected across portions of central and northeast Florida coastal waters Thu into early Fri. $$ Konarik