Hurricane Ernesto Discussion Number  14
NWS National Hurricane Center Miami FL       AL052024
1100 PM AST Wed Aug 14 2024

The satellite structure of Ernesto has somewhat improved tonight. A 
series of earlier SSMI/S 91 GHz passive microwave images showed the 
formation of a mid-level eye, and there have been recent hints of an 
eye trying to emerge in proxy-visible satellite images. Data from 
the Air Force Hurricane Hunters showed the central pressure has 
fallen to 982 mb, and the aircraft measured peak 700-mb flight-level 
winds of 76 kt in the northeast quadrant. Based on these data, the 
initial intensity is set at 70 kt. The wind field remains quite 
broad and asymmetric, with the strongest aircraft winds well to the 
northeast of the center. The next aircraft reconnaissance mission 
into Ernesto is scheduled for tomorrow morning.  

Ernesto is now moving north-northwestward at 330/14 kt. The 
hurricane will continue on a north-northwestward to northward motion 
during the next day or so while moving through a break in the 
subtropical ridge over the western Atlantic. The global models agree 
the upper trough that weakened the ridge will not capture Ernesto. 
As a result, Ernesto will move slower to the north-northeast and 
north while the hurricane approaches and moves near Bermuda Friday 
night and Saturday. Later this weekend, a second trough will move 
across the eastern U.S., and Ernesto should accelerate northeastward 
early next week within the deep-layer southwesterly flow ahead of 
this feature. The NHC track forecast is essentially an update of the 
previous one, as the track guidance remains in good overall 
agreement. It is still too soon to know exactly how close Ernesto's 
center will move to Bermuda this weekend, but warnings will likely 
be required for the island on Thursday.

While there is still evidence of some drier air nearby Ernesto, the 
very warm ocean waters and weak to moderate shear should promote 
some strengthening during the next couple of days. This is supported 
by the bulk of the intensity guidance, and the regional hurricane 
models still favor Ernesto reaching major hurricane intensity on 
Friday. The latest NHC prediction remains on the high end of the 
guidance envelope, closest to the HFIP corrected consensus. Some 
gradual weakening is forecast thereafter as Ernesto moves into a 
drier, more sheared environment. There are some indications that 
positive interaction with the second upper trough could cause 
Ernesto's intensity to level off or even slightly increase during 
the 60-96 h time period while still over warm waters. By 120 h, the 
model fields suggest Ernesto will be on the verge of losing tropical 
characteristics while accelerating over cooler waters.


Key Messages:

1. Hurricane conditions are possible on Bermuda on Saturday, with 
tropical storm conditions possible by Friday afternoon. Rainfall 
associated with Ernesto may begin to affect Bermuda late Thursday 
and result in flash flooding across Bermuda later this week and this 
weekend.

2. 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  15/0300Z 23.0N  68.9W   70 KT  80 MPH
12H  15/1200Z 24.7N  69.1W   80 KT  90 MPH
24H  16/0000Z 26.8N  68.6W   90 KT 105 MPH
36H  16/1200Z 28.6N  67.4W  100 KT 115 MPH
48H  17/0000Z 30.5N  66.1W   95 KT 110 MPH
60H  17/1200Z 32.2N  65.5W   90 KT 105 MPH
72H  18/0000Z 34.0N  65.2W   90 KT 105 MPH
96H  19/0000Z 38.5N  63.0W   90 KT 105 MPH
120H  20/0000Z 45.0N  55.0W   75 KT  85 MPH

$$
Forecaster Reinhart