Hurricane Ernesto Discussion Number  22
NWS National Hurricane Center Miami FL       AL052024
1100 PM AST Fri Aug 16 2024

Ernesto is very near Bermuda.  The island has been in the northern 
rainbands since this afternoon, and the eyewall is closing in on the 
island as seen in Bermuda's Doppler radar images.  So far, 
tropical-storm-force winds with gusts to hurricane force have been 
observed on Bermuda, and the strongest winds will likely occur there 
during the next several hours.  The Air Force Hurricane Hunters have 
been investigating Ernesto this evening and found that the minimum 
pressure has been steady around 969 mb.  A blend of the latest 
flight-level and SFMR winds support an initial intensity of about 80 
kt.  Recent microwave images indicate that the vortex is tilted to 
the east-northeast with height due to about 20 kt of 
west-southwesterly vertical wind shear.

The already tilted vortex coupled with continued moderate to strong 
shear and possible intrusions of dry air should cause some weakening 
during the next day or so.  However, the shear is expected to lessen 
during the 24- to 60-h time period, and since Ernesto will still be 
over the Gulf Stream Current then, the weakening trend should pause. 
In fact, Ernesto is forecast to strengthen some during that time, 
following the hurricane regional models and consensus aids.  On 
Monday, the cyclone is predicted to cross the north wall of the Gulf 
Stream and track over sharply cooler waters while moving into a 
strong wind shear environment.  Therefore, steady weakening is 
forecast at that point, and Ernesto is expected to complete 
extratropical transition shortly after day 3.  The NHC intensity 
forecast is largely an update of the previous one.

Ernesto is still moving northeastward at 11 kt, however, the 
hurricane is expected to slow down soon as the trough off Atlantic 
Canada continues to lift out.  The expected slower motion and 
Ernesto's large size will cause a long duration of impacts through 
Saturday night on Bermuda.  After the hurricane pulls away from 
Bermuda, another trough is forecast to push off the U.S. east coast. 
This feature should cause the cyclone to accelerate northeastward 
later in the weekend and early next week, taking Ernesto near 
Newfoundland Monday night.  The NHC track forecast is a little 
slower than the previous one to come into better agreement with the 
latest models.


Key Messages:

1. Ernesto is expected to bring a prolonged period of strong winds
and storm surge on Bermuda through Saturday night.  A hurricane
warning is in effect for the island.  Residents there should listen
to orders from local officials.

2. Heavy rainfall associated with Ernesto is expected to impact
Bermuda through Saturday and will likely result in considerable
life-threatening flash flooding, especially in low-lying areas on
the island.

3. Even though Ernesto is forecast to remain well offshore the U.S.
East Coast, swells generated by the hurricane are expected to affect
the area through 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 Bahamas, Bermuda, and Atlantic Canada
during the next few days.


FORECAST POSITIONS AND MAX WINDS

INIT  17/0300Z 31.4N  65.2W   80 KT  90 MPH
12H  17/1200Z 32.6N  64.6W   75 KT  85 MPH
24H  18/0000Z 33.7N  64.1W   70 KT  80 MPH
36H  18/1200Z 35.3N  63.4W   75 KT  85 MPH
48H  19/0000Z 38.1N  61.9W   80 KT  90 MPH
60H  19/1200Z 41.5N  59.1W   80 KT  90 MPH
72H  20/0000Z 45.1N  54.1W   65 KT  75 MPH
96H  21/0000Z 51.3N  36.9W   45 KT  50 MPH...POST-TROP/EXTRATROP
120H  22/0000Z 54.7N  17.4W   35 KT  40 MPH...POST-TROP/EXTRATROP

$$
Forecaster Cangialosi