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| #1149663 (Received by flhurricane at: 11:03 AM 27.Aug.2023) TCDAT5 Tropical Depression Ten Discussion Number 4 NWS National Hurricane Center Miami FL AL102023 1000 AM CDT Sun Aug 27 2023 So far this morning, the overall cloud pattern of the tropical cyclone has not become significantly better organized. The small center is partially exposed on GOES-16 visible imagery, and convective banding features are still not very well defined. The current intensity is held at 30 kt for this advisory which is in line with the latest Dvorak Satellite estimates. A NOAA Hurricane Hunter aircraft, flying at around 12000 ft, is near the center of the system taking Doppler radar wind velocity measurements. These data should provide valuable information on the structure of the cyclone for initializing the numerical weather prediction models. The center of the cyclone appears to have been moving in a small clockwise loop overnight and into this morning, and it will probably complete this loop today. The initial motion estimate is now around 090/2 kt. Steering currents should remain weak through today and tonight. Beginning on Monday, a mid-level ridge starts to build near southern Florida and eastward. This evolution should cause a generally northward motion during the next couple of days. In 48 to 72 hours, a mid-level trough dropping into the eastern U.S. will likely induce a turn toward the north-northeast and take the system across the northeast Gulf of Mexico coast on Wednesday. The official forecast track has been nudged to the right of the previous one, but is not quite as far east as the latest corrected consensus, HCCA, prediction. Users are reminded not to focus on the exact forecast track, since strong winds, heavy rains and dangerous storm surges extend well away from the center. The cyclone will be moving over waters of high oceanic heat content over the eastern Gulf of Mexico and within a moist mid- to low-level air mass for the next few days. An upper-tropospheric trough is predicted to develop over the western Gulf of Mexico in 48 to 72 hours. Although this feature could produce some moderate southwesterly vertical wind shear over the system, positive vorticity advection and diffluent upper-level flow to the east of the trough will likely be conducive for strengthening. The official forecast, like the previous one, calls for the cyclone to reach hurricane status over the eastern Gulf of Mexico in 48 to 72 hours. This is at the high end of the latest intensity model guidance. KEY MESSAGES: 1. The depression is forecast to become a hurricane over the eastern Gulf of Mexico, and there is an increasing risk of life-threatening storm surge, flooding from heavy rainfall, and hurricane-force winds along portions of the west coast of Florida and the Florida Panhandle beginning as early as Tuesday. Although it is too soon to specify the exact location and magnitude of these impacts, residents in these areas should monitor updates to the forecast, have their hurricane plan in place, and follow any advice given by local officials. Storm surge and hurricane watches may be required for portions of the Gulf coast of Florida later today. 2. Heavy rainfall is expected across the eastern Yucatan Peninsula and western Cuba and may produce areas of flash and urban flooding and landslides across western Cuba. The depression is forecast to become a tropical storm later today, and tropical storm conditions are expected over portions of the Yucatan Peninsula and extreme western Cuba with tropical storm conditions possible on the Isle of Youth. 3. Scattered flooding from heavy rainfall is likely over in portions of the southeast U.S. by mid to late week. FORECAST POSITIONS AND MAX WINDS INIT 27/1500Z 19.9N 85.8W 30 KT 35 MPH 12H 28/0000Z 19.7N 85.9W 40 KT 45 MPH 24H 28/1200Z 20.6N 85.7W 45 KT 50 MPH 36H 29/0000Z 21.9N 85.5W 50 KT 60 MPH 48H 29/1200Z 24.0N 85.2W 60 KT 70 MPH 60H 30/0000Z 26.2N 85.0W 75 KT 85 MPH 72H 30/1200Z 28.9N 84.0W 80 KT 90 MPH 96H 31/1200Z 33.0N 79.5W 45 KT 50 MPH...INLAND 120H 01/1200Z 34.5N 74.0W 45 KT 50 MPH...OVER WATER $$ Forecaster Pasch |
