000
WTNT42 KNHC 020846
TCDAT2

TROPICAL STORM GASTON DISCUSSION NUMBER  43
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL072016
500 AM AST FRI SEP 02 2016

Conventional satellite imagery and two earlier microwave images
show the center of circulation decoupled well to the west of the
remaining deep convection.  The initial intensity is decreased to
55 kt for this advisory and is based on a blend of the subjective
and objective satellite intensity estimates.  Continued weakening is
expected as the cyclone traverses cooler oceanic sea surface
temperatures and remains in a strong vertical shear environment.
Gaston is forecast to degenerate into a remnant low in 36 hours,
with dissipation in about 48 hours.  The NHC intensity forecast is
similar to the previous one, and is close to the IVCN intensity
consensus model.

Because Gaston's low-level circulation has decoupled from the
mid-level flow due to the persistent strong shear, the cyclone's
forward speed has decreased while moving eastward, or 080/13 kt.
This general motion is expected to continue during the next couple
of days.  At the 36-hour period, Gaston should turn northeastward in
response to a frontal system approaching from the northwest and
open up into a trough of low pressure in a couple of days.  The NHC
track foreast remains near the middle of the tightly clustered model
guidance and is similar to the previous advisory.

FORECAST POSITIONS AND MAX WINDS

INIT  02/0900Z 38.5N  34.5W   55 KT  65 MPH
 12H  02/1800Z 38.9N  31.8W   50 KT  60 MPH
 24H  03/0600Z 39.7N  29.0W   40 KT  45 MPH
 36H  03/1800Z 41.3N  26.3W   30 KT  35 MPH...POST-TROP/REMNT LOW
 48H  04/0600Z...DISSIPATED

$$
Forecaster Roberts/Stewart