466 
WTNT45 KNHC 140238
TCDAT5

Tropical Storm Joyce Discussion Number   6
NWS National Hurricane Center Miami FL       AL102018
1100 PM AST Thu Sep 13 2018

Beginning around 6 hours ago, convection redeveloped near the center
of Joyce.  Since then, the cyclone has become displaced from the
upper-level low, and an ASCAT overpass around 2330 UTC showed that
Joyce has a small radius of maximum winds of around 30 n mi. Based
on these factors, it appears Joyce has become a tropical cyclone.
The ASCAT pass showed maximum winds of just over 30 kt, but its
possible the instrument slightly under-sampled the maximum winds of
the small cyclone.  In addition, convection near the center
increased somewhat after the time of the ASCAT pass. The initial
intensity has therefore been held at 35 kt, making Joyce a tropical
storm.

Joyce has accelerated a little toward the west-southwest, perhaps
more than previously anticipated.  As a result, the forecast has
been shifted south at most forecast hours, but not quite as far as
the consensus models would suggest. There is otherwise no change
to the track forecast reasoning, and Joyce is still expected to move
slowly generally southward while Helene passes to the east until
accelerating toward the northeast ahead of a mid-latitude trough in
a day or two.

Despite the recent, and perhaps temporary, resurgence of
convection, no change has been made to the intensity forecast.
None of the guidance shows much intensification, and the NHC
forecast continues to rely on a blend of the intensity consensus
and the GFS and ECMWF, which only show gradual weakening throughout
the forecast period.  Considering that the cyclone has only
gradually weakened to this point, this still seems like a reasonable
forecast.

FORECAST POSITIONS AND MAX WINDS

INIT  14/0300Z 32.9N  44.4W   35 KT  40 MPH
 12H  14/1200Z 32.2N  44.7W   35 KT  40 MPH
 24H  15/0000Z 31.7N  44.2W   35 KT  40 MPH
 36H  15/1200Z 32.2N  43.3W   35 KT  40 MPH
 48H  16/0000Z 33.3N  42.1W   30 KT  35 MPH
 72H  17/0000Z 36.0N  37.5W   30 KT  35 MPH
 96H  18/0000Z...DISSIPATED

$$
Forecaster Zelinsky