Official Discussion issued by the National Hurricane Center
Ernesto (AL052024) DATA RELEASED: 8/14/2024 3:00:00 PM UTC
Copy of official data Hurricane Ernesto Discussion Number 12 NWS National Hurricane Center Miami FL AL052024 1100 AM AST Wed Aug 14 2024 An Air Force Reserve Hurricane Hunter aircraft measured a peak 700-mb flight-level wind of 70 kt northeast of Ernesto's center, and the crew reported a 50 percent eyewall. In addition, Tail Doppler radar from the NOAA P-3 aircraft measured winds over 75 kt at an elevation of 500 meters. Based on these data, Ernesto is upgraded to a 65-kt hurricane. Ernesto continues to move northwestward, or 310/14 kt, but is expected to turn north-northwestward and northward later today and tonight as it moves through a break in the subtropical ridge caused by a deep-layer trough off the east coast of the United States. This trough is expected to leave Ernesto behind later this week, which should cause a reduction in speed on Saturday and Sunday while the storm is passing Bermuda. By early next week, a second trough moving across the eastern United States should cause Ernesto to accelerate toward the north and north-northeast over the waters south of Atlantic Canada. The track guidance is in good agreement during the first 48 hours, and the official forecast was only shifted slightly westward to account for Ernesto's recent motion. After 48 hours, there is more divergence in the track models, with the GFS on the eastern edge of the envelope while the ECMWF shows less turning and is on the western edge of the envelope. The NHC forecast has been nudged westward during this period and is very close to the dynamical hurricane models. Although Ernesto is moving over very warm waters, the hurricane might have to deal with bouts of increased shear and nearby dry air during the next several days. That said, the intensity guidance shows continued gradual strengthening, and the official forecast still reflects the possibility of Ernesto becoming a major hurricane in about 48 hours. Much of the intensity guidance has come down on the peak intensity this cycle, but for now we'll maintain continuity and wait to see if this trend continues. Key Messages: 1. Heavy rainfall will result in locally considerable flash flooding and mudslides today over the Virgin Islands and into portions of Puerto Rico. 2. Tropical storm conditions, especially in gusts, are expected to continue over the Virgin Islands, Puerto Rico, Culebra, and Vieques through today. 3. Ernesto is likely to bring impacts to Bermuda late this week, and interests there should monitor the progress of this system. A Hurricane Watch may be required later today. 4. Even though Ernesto is forecast to remain well offshore the U.S. East Coast, swells generated by the storm are expected to reach the area late this week and into the weekend. Beach goers should be aware of a significant risk of life-threatening surf and rip currents, and stay out of the water if advised by lifeguards. Surf and rip currents are also possible on the Virgin Islands, Puerto Rico, the Dominican Republic, the Turks and Caicos, and the Bahamas during the next few days. FORECAST POSITIONS AND MAX WINDS INIT 14/1500Z 20.5N 67.6W 65 KT 75 MPH 12H 15/0000Z 22.3N 68.7W 70 KT 80 MPH 24H 15/1200Z 24.5N 69.2W 80 KT 90 MPH 36H 16/0000Z 26.6N 68.6W 90 KT 105 MPH 48H 16/1200Z 28.5N 67.2W 100 KT 115 MPH 60H 17/0000Z 30.4N 66.1W 95 KT 110 MPH 72H 17/1200Z 32.0N 65.8W 90 KT 105 MPH 96H 18/1200Z 36.0N 65.4W 85 KT 100 MPH 120H 19/1200Z 42.6N 61.0W 80 KT 90 MPH $$ Forecaster Berg |