053 WTNT43 KNHC 161452 TCDAT3 Potential Tropical Cyclone Eight Discussion Number 4 NWS National Hurricane Center Miami FL AL082024 1100 AM EDT Mon Sep 16 2024 The low pressure system that the NHC has been monitoring off the Carolina coast has not become better organized this morning. The low-level circulation remains elongated and not well defined, based on overnight data from the Air Force Hurricane Hunters and recent visible satellite images. The flight-level temperature data from the aircraft also suggested a frontal boundary remains in close proximity to the low, which is consistent with the cloud pattern of the system. The strongest winds and heaviest rains lie to the north and northeast of the estimated center and are currently spreading across southeastern North Carolina. Based on surface synoptic observations, the initial intensity is set at 45 kt. Aircraft data and satellite images indicate the elongated center lies a bit north of previous estimates, with an uncertain initial motion of north-northwestward at 4 kt. This general motion should continue today, bringing the center toward the coast of South Carolina and inland within the warning area later today. However, it should be noted that much of the hazardous weather conditions extend well to the northeast of the center and are currently moving onshore over the Cape Fear region of North Carolina. A northwestward motion is forecast to continue over land while the weakening low spins down. The updated NHC track forecast lies a bit to the right of the previous prediction based on the latest track consensus aids. With limited time before it moves inland, the chances of this system becoming a tropical or subtropical cyclone continue to decrease. The intensity guidance shows quick weakening once the low crosses the coastline, and the official NHC intensity forecast brings the system down to 30 kt in 12 h, on the lower end of the guidance envelope but consistent with the global model fields. Weakening should continue through dissipation, which is forecast to occur on Wednesday. Key Messages: 1. Tropical storm conditions are expected along portions of the coasts of South Carolina and North Carolina within the Tropical Storm Warning area during the next several hours. 2. Locally considerable flash and urban flooding and minor river flooding is possible across southeast North Carolina and northeast South Carolina through tonight. There is also a risk of isolated flash and urban flooding across much of the Mid-Atlantic region through Wednesday. 3. Coastal flooding and high surf are likely along portions of the southeastern U.S. coast through this afternoon. FORECAST POSITIONS AND MAX WINDS INIT 16/1500Z 32.9N 78.3W 45 KT 50 MPH...POTENTIAL TROP CYCLONE 12H 17/0000Z 33.7N 79.2W 30 KT 35 MPH...POST-TROP/EXTRATROP 24H 17/1200Z 34.3N 79.9W 25 KT 30 MPH...POST-TROP/EXTRATROP 36H 18/0000Z 35.0N 80.7W 20 KT 25 MPH...POST-TROP/EXTRATROP 48H 18/1200Z...DISSIPATED $$ Forecaster Reinhart
Potential Tropical Cyclone Eight Forecast Discussion
16
Sep