Official Discussion issued by the National Hurricane Center
Debby (AL042024) DATA RELEASED: 8/5/2024 9:00:00 PM UTC
Copy of official data Tropical Storm Debby Discussion Number 14 NWS National Hurricane Center Miami FL AL042024 500 PM EDT Mon Aug 05 2024 Debby continues to move over land, and based on surface synoptic and radar observations the center is estimated to be near the Florida/Georgia border. Assuming a continued weakening since landfall, the intensity estimate has been reduced to 45 kt, which is reasonably consistent with the latest WSR-88D radar velocities aloft. Debby continues to move through a weakness in the subtropical high, and the forward motion has slowed to about 035/6 kt. The cyclone is expected to turn eastward, while moving quite slowly, in a region of weak steering currents for the next couple of days. This motion should bring the center of the system back over water by late Tuesday. In around 72 hours, a mid-level ridge to the east of Debby is forecast to build somewhat, and as a result, the center should move inland over South Carolina and turn northward and northeastward over the eastern U.S. for the remainder of the forecast period. The NHC track forecast is similar to the previous one and is in good agreement with the corrected model consensus, HCCA, guidance. The tropical cyclone should continue to weaken while it moves over land for the next day or so. By late Tuesday, assuming the center of the system moves back over water, some re-intensification is forecast. The NHC forecast continues to show only modest restrengthening due to the uncertainties, although this may be conservative. Given the sluggish forward motion of Debby, extremely large amounts of rainfall over the Southeastern U.S. is anticipated. Key Messages: 1. Potentially historic heavy rainfall across southeast Georgia and the coastal plain of South Carolina through Saturday morning will likely result in areas of catastrophic flooding. Heavy rainfall will likely result in considerable flooding impacts from portions of central and northern Florida and across portions of central and northeast North Carolina through Saturday morning. 2. Dangerous storm surge and tropical storm conditions will spread northward along the southeast U.S. coast from northeastern Florida to North Carolina through the middle of the week. Storm Surge and Tropical Storm watches and warnings have been issued for portions of these areas. Residents in the Storm Surge watch and warning area should follow any advice given by local officials. 3. In portions of Florida where Debby has passed, deadly hazards remain, including downed power lines and flooded areas. Ensure generators are properly ventilated to avoid carbon monoxide poisoning. Exercise caution when using chainsaws and power tools, and drink plenty of water to avoid heat exhaustion. FORECAST POSITIONS AND MAX WINDS INIT 05/2100Z 30.5N 82.9W 45 KT 50 MPH 12H 06/0600Z 31.2N 82.1W 35 KT 40 MPH...INLAND 24H 06/1800Z 31.7N 81.2W 35 KT 40 MPH...INLAND 36H 07/0600Z 31.7N 80.1W 35 KT 40 MPH...OVER WATER 48H 07/1800Z 32.1N 79.2W 40 KT 45 MPH...OVER WATER 60H 08/0600Z 32.6N 79.1W 45 KT 50 MPH...OVER WATER 72H 08/1800Z 33.2N 79.2W 50 KT 60 MPH...INLAND 96H 09/1800Z 35.3N 79.1W 30 KT 35 MPH...INLAND 120H 10/1800Z 38.5N 75.5W 30 KT 35 MPH...INLAND $$ Forecaster Pasch |