000 WTNT41 KNHC 200844 TCDAT1 Hurricane Oscar Discussion Number 5 NWS National Hurricane Center Miami FL AL162024 500 AM EDT Sun Oct 20 2024 Animation of 1-minute GOES infrared satellite images indicates that Oscar's center has made landfall on the eastern side of Great Inagua Island in the southeastern Bahamas. Small convective bursts have occasionally been noted close to the center during the overnight hours, suggesting that the hurricane still has a very tight inner core. Overall, the satellite presentation is not quite as well organized as it was yesterday afternoon, and with the small core now over Great Inagua, the estimated intensity is lowered slightly to 70 kt--albeit with a very large error bar. An Air Force Reserve Hurricane Hunter mission is scheduled to investigate Oscar in a few hours. Oscar is moving south of due west (260 degrees), still at about 10 kt. Due to strong mid-level ridging to the north and west, Oscar is forecast to turn west-southwestward this morning, which will bring the center to the coast of northeastern Cuba later this afternoon. The ridge is expected to be replaced by a developing mid- to upper-level trough over the western Atlantic in 24-48 hours, which should cause Oscar to turn westward and then northward while inland over Cuba on Monday. Oscar is then forecast to accelerate northeastward over the central Bahamas on Tuesday ahead of the trough. The NHC track forecast is very close to the HCCA consensus aid for the first 36 hours of the forecast, and then more closely follows a blend of HCCA with TVCA after that time. This forecast is not too different from the previous prediction. Oscar's small size will continue to make it susceptible to intensity fluctuations, but the cyclone is expected to reach northeastern Cuba as a hurricane later this afternoon. That small size will also make the core vulnerable to being heavily disrupted by the terrain of eastern Cuba, which rises several thousand feet above sea level. Because of this, the GFS and ECMWF global fields in particular show Oscar's circulation becoming less compact and less well defined in about 36 hours. Oscar is forecast to weaken over Cuba, but it could still be a tropical storm when it emerges back over the Atlantic and moves across the central Bahamas in 2-3 days. Alternatively, it's also possible the Oscar could degenerate into a remnant low or dissipate entirely while over eastern Cuba. If Oscar does survive Cuba, it is likely to be absorbed by a larger non-tropical area of low pressure over the western Atlantic, and the new NHC forecast therefore shows dissipation by day 4. Key Messages: 1. A Hurricane Warning remains in effect for the southeastern Bahamas and for a portion of the northeastern coast of Cuba. 2. Oscar is expected to produce a dangerous storm surge on portions of the southeastern Bahamas this morning, especially Great Inagua Island, and along the north shore of Cuba later this afternoon and evening. 3. Heavy rainfall from Oscar will lead to areas of flash flooding along with possible mudslides across portions of eastern Cuba, especially within the Sierra Maestra, through Tuesday. FORECAST POSITIONS AND MAX WINDS INIT 20/0900Z 21.1N 73.1W 70 KT 80 MPH 12H 20/1800Z 20.6N 74.3W 70 KT 80 MPH 24H 21/0600Z 20.4N 75.4W 50 KT 60 MPH...INLAND 36H 21/1800Z 20.8N 76.1W 40 KT 45 MPH...INLAND 48H 22/0600Z 21.7N 76.0W 40 KT 45 MPH...OVER WATER 60H 22/1800Z 22.7N 75.2W 35 KT 40 MPH 72H 23/0600Z 23.8N 74.0W 35 KT 40 MPH 96H 24/0600Z...DISSIPATED $$ Forecaster Berg