767 WTNT41 KNHC 201459 TCDAT1 Hurricane Oscar Discussion Number 6 NWS National Hurricane Center Miami FL AL162024 1100 AM EDT Sun Oct 20 2024 Oscar remains a compact hurricane as it nears its next landfall in the northeastern coast of Cuba. The Air Force Reserve Reconnaissance has been performing another resources permitting mission, finding that Oscar remains a small hurricane, though the last several fixes do indicate the eye is a bit larger than observed yesterday, with a 15-20 mile wide eye. This eye feature is also being occasionally observed on radar imagery from Guantanamo Bay. On satellite, Oscar still remains well organized with a small central dense overcast with very cold cloud tops below -80 C. In fact, the subjective and objective intensity estimates based on satellite are quite a bit higher than yesterday at this time. From the aircraft in-situ data, a blend of the flight level, SFMR, and dropsonde data still supports a current intensity of 70 kt this advisory. Oscar has made its turn to the west-southwest, with the current estimated motion from recon fixes at 250/7 kt. The narrow mid-level ridge that was originally north of Oscar has shifted westward while a weakness develops farther east from a mid-latitude trough, and that has resulted in the steering over the hurricane shifting more equatorward, allowing the west-southwestward motion. However, the trough's weakness will continue to grow and also migrate westward, and Oscar still seems likely to slow to a crawl after it moves inland over Cuba. Ultimately Oscar is still expected to reemerge into the southwestern Atlantic in 36 h and migrate northeastward as it becomes captured by the deep-layer trough. The NHC track forecast remains close to the HCCA and TVCA consensus aids, and is quite similar to the prior track forecast. Oscar appears to be holding its own today, and not much change in intensity is expected before it reaches the northeastern Cuba coast this afternoon as a hurricane. There is high terrain in eastern Cuba that is likely to severely disrupt the small inner-core of Oscar after it moves inland. Some of the global model guidance (especially the GFS) shows that Oscar could weaken more over than shown here. Assuming Oscar survives its passage over Cuba, the NHC forecast shows it emerging back offshore as a tropical storm in 36-48 h. Environmental conditions will be quite unfavorable for additional tropical development by that time, with increasing northwesterly shear and very dry mid-level air. Ultimately Oscar will finally be absorbed by a larger deep-layer baroclinic trough over the western Atlantic after 72 h, similar to the prior forecast. 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 Wednesday. In addition, localized flash flooding will be possible across the southeastern Bahamas through Wednesday. FORECAST POSITIONS AND MAX WINDS INIT 20/1500Z 20.7N 73.9W 70 KT 80 MPH 12H 21/0000Z 20.4N 74.8W 65 KT 75 MPH...INLAND 24H 21/1200Z 20.5N 75.6W 45 KT 50 MPH...INLAND 36H 22/0000Z 21.1N 76.0W 40 KT 45 MPH...OVER WATER 48H 22/1200Z 22.1N 75.7W 40 KT 45 MPH 60H 23/0000Z 23.0N 75.0W 40 KT 45 MPH 72H 23/1200Z 24.0N 73.7W 35 KT 40 MPH 96H 24/1200Z...DISSIPATED $$ Forecaster Papin