Official Discussion issued by the National Hurricane Center

Epsilon (AL272020) DATA RELEASED: 10/19/2020 9:00:00 PM UTC

Copy of official data

Tropical Storm Epsilon Discussion Number   3
NWS National Hurricane Center Miami FL       AL272020
500 PM AST Mon Oct 19 2020

Earlier this afternoon, Epsilon had a hybrid-type structure in 
satellite imagery, with a partially exposed center and a broken 
convective band that wrapped around the northern and eastern sides 
of the storm. However, recent satellite imagery shows a small 
convective burst near the center that gives Epsilon a more tropical 
appearance. ASCAT-B/C passes from this morning indicate the system 
has a large and asymmetric wind field, with 34-kt winds extending 
over 200 nm away from the center in the northern semicircle. This 
is, in part, attributable to the environmental pressure gradient 
with a strong high pressure ridge centered east of the Canadian 
Maritimes. The initial intensity is raised to 40 kt with this 
advisory, supported by a T2.5 subjective Dvorak classification from 
TAFB and a 37-kt objective 14Z SATCON estimate.

Warm sea-surface temperatures and moderate southwesterly vertical 
wind shear should allow for gradual strengthening over the next day 
or so. By 36-48 h, a period of weaker wind shear should allow 
Epsilon to continue strengthening while becoming better organized 
and eventually developing a more symmetric wind field. There is 
still increasing spread in the intensity guidance beyond 48 h, with 
a split between the stronger statistical-dynamical guidance and the 
weaker regional hurricane models. Given these mixed signals, little 
change was made to the intensity forecast with this advisory. The
official NHC intensity forecast lies on the higher end of the 
guidance consensus, but remains lower than SHIPS/LGEM. The official 
forecast now calls for Epsilon to become a hurricane on Wednesday.

Epsilon remains nearly stationary as it meanders over the central 
Atlantic under weak steering currents. The cyclone should begin 
moving slowly northward tonight, then turn northwestward with a 
faster forward speed through midweek as a mid- to upper-level ridge 
is expected to build to the north and northeast of Epsilon. The 
current NHC forecast track shows Epsilon making its closest approach 
to Bermuda on Friday. By this weekend, the cyclone should begin 
turning northward ahead of an upper-level trough expected to move 
off the northeastern U.S. coast. Most of the track guidance is 
tightly clustered for the next several days, except for the latest 
HWRF. The track guidance has shifted slightly to the right, and so 
the NHC track forecast has been adjusted similarly to reflect the 
latest guidance consensus.

Key Message:

1. Epsilon is forecast to be at or near hurricane strength when
it approaches Bermuda late this week.  While it is too soon to
determine the exact details of Epsilon's track and intensity near
the island, there is a risk of direct impacts from wind, rainfall,
and storm surge on Bermuda, and interests there should closely
monitor the progress of Epsilon.


INIT  19/2100Z 25.5N  55.5W   40 KT  45 MPH
12H  20/0600Z 25.9N  55.5W   45 KT  50 MPH
24H  20/1800Z 27.0N  56.1W   55 KT  65 MPH
36H  21/0600Z 28.1N  57.8W   60 KT  70 MPH
48H  21/1800Z 28.8N  59.4W   65 KT  75 MPH
60H  22/0600Z 29.8N  60.6W   70 KT  80 MPH
72H  22/1800Z 31.1N  61.5W   75 KT  85 MPH
96H  23/1800Z 32.8N  62.8W   80 KT  90 MPH
120H  24/1800Z 35.5N  62.3W   80 KT  90 MPH

Forecaster Reinhart/Brown