Issued at 500 PM EDT Mon Oct 21 2024
000 WTNT41 KNHC 212042 TCDAT1 Tropical Storm Oscar Discussion Number 11 NWS National Hurricane Center Miami FL AL162024 500 PM EDT Mon Oct 21 2024 Although the circulation of Oscar is rather broad, visible satellite images show that the center is nearing the northern coast of eastern Cuba. Deep convection associated with the system has diminished during the day, at least partially due to a diurnal fluctuation. The intensity is kept, perhaps generously, at 35 kt for this advisory. Surface synoptic observations and earlier scatterometer data indicate that the strongest winds are over the eastern semicircle of the cyclone, and no tropical-storm-force wind radii are shown to the northwest or southwest of the center for this advisory. Oscar been turning fairly sharply to the right while the system executes a hairpin turn over eastern Cuba. The current motion estimate is around 330/6 kt. The tropical cyclone is expected to turn northward and northeastward with some increase in forward speed while it moves on the southeastern and eastern side of a mid-level trough. Since the system has moved a little farther west than previously estimated, the overall official track forecast has been shifted slightly west of the previous one. This is a blend of the simple and corrected dynamical model consensus predictions. The tropical cyclone should move back over water soon, so some restrengthening is possible during the next day or two. However, Oscar will be moving into an area of strong upper-level winds over the next couple of days which should impart significant westerly shear over the system. Also, the cyclone is expected to remain in a relatively dry air mass to the north of the Greater Antilles. Thus, only slight restrengthening seems possible. The official intensity forecast is above the latest SHIPS and LGEM guidance. In 2 to 3 days, the global models show the system being absorbed by a non-tropical low pressure system to the west of Bermuda. The primary hazard associated with Oscar will continue to be heavy rainfall and life-threatening flash flooding, particularly over the mountainous terrain of eastern Cuba. Over the last 24 hours, a rainfall total of nearly 15 inches was reported at Punta de Maisi on the eastern tip of Cuba. Key Messages: 1. Through midweek, heavy rainfall from Oscar will lead to areas of significant, life-threatening flash flooding along with mudslides across portions of eastern Cuba, especially within the Sierra Maestra. In addition, localized flash flooding will be possible across the southeastern Bahamas. 2. Tropical storm conditions are expected to continue into this evening across portions of eastern Cuba. Tropical storm conditions are also expected in portions of the southeastern and central Bahamas tonight and Tuesday. FORECAST POSITIONS AND MAX WINDS INIT 21/2100Z 21.0N 76.1W 35 KT 40 MPH...INLAND 12H 22/0600Z 21.8N 75.4W 35 KT 40 MPH...OVER WATER 24H 22/1800Z 23.3N 74.1W 40 KT 45 MPH 36H 23/0600Z 25.0N 72.4W 40 KT 45 MPH 48H 23/1800Z 27.4N 70.2W 40 KT 45 MPH 60H 24/0600Z 31.5N 67.4W 40 KT 45 MPH 72H 24/1800Z...ABSORBED BY NON-TROPICAL LOW PRESSURE AREA $$ Forecaster Pasch/Delgado
