000
WTNT45 KNHC 260237
TCDAT5

Tropical Storm Dorian Discussion Number   7
NWS National Hurricane Center Miami FL       AL052019
1100 PM AST Sun Aug 25 2019

Dorian's cloud pattern hasn't changed much since this afternoon,
with deep convection oscillating up and down.  There are few banding
features evident, and the upper-level outflow is somewhat restricted
over the eastern semicircle of the circulation.  The intensity
estimate remains at 45 kt and is in agreement with a recent Dvorak
estimate from TAFB.  The intensity forecast for this storm is a
challenge, since the numerical guidance depicts a wide range of
possibilities.  The GFS and ECMWF global models dissipate Dorian
over the Caribbean in about 4 days, probably due to the hostile
environment associated with an upper-level low near Hispaniola.
Another unfavorable factor could be dry air that is also forecast by
the global models over the Caribbean.  On the other hand, the
statistical/dynamical models DSHIPS and LGEM do not weaken the
system until it interacts with the land mass of Hispaniola.  The
official forecast is close to the intensity model consensus, IVCN,
but it should be noted that there is greater than usual uncertainty
associated with this forecast.

The motion continues to be slightly north of due west or 280/12.
Dorian is moving along the southern side of the subtropical ridge.
The track models are in good agreement that the cyclone will
gradually turn toward the west-northwest on Monday.  A slight
weakness in the ridge near 70W longitude in a couple of days should
induce a gradual turn to the northwest later in the forecast period.
The official track forecast is close to the corrected consensus,
HCCA prediction and is also very close to the previous NHC track.

Key Messages:

1. Dorian is expected to bring tropical storm conditions to
portions of the Lesser Antilles, where tropical storm watches and
warnings are in effect.  Residents in these areas should refer to
advice from local government officials and products from their
local meteorological service for additional information.

2. Dorian is expected to produce 2 to 4 inches of rainfall across
portions of the Lesser Antilles, with isolated amounts as high as 6
inches.

3.  While it is too soon to determine the specific time or
magnitude of possible direct impacts in Puerto Rico, the Virgin
Islands, or Hispaniola interests in those areas should monitor the
progress of Dorian.


FORECAST POSITIONS AND MAX WINDS

INIT  26/0300Z 11.7N  55.3W   45 KT  50 MPH
 12H  26/1200Z 12.1N  57.0W   50 KT  60 MPH
 24H  27/0000Z 12.8N  59.3W   55 KT  65 MPH
 36H  27/1200Z 13.7N  61.5W   55 KT  65 MPH
 48H  28/0000Z 14.8N  63.6W   60 KT  70 MPH
 72H  29/0000Z 17.2N  67.6W   65 KT  75 MPH
 96H  30/0000Z 19.5N  71.0W   40 KT  45 MPH...INLAND
120H  31/0000Z 21.5N  74.0W   25 KT  30 MPH...OVER WATER

$$
Forecaster Pasch/Latto