Tropical Storm Leslie Discussion Number  49
NWS National Hurricane Center Miami FL       AL132018
1100 AM AST Mon Oct 08 2018

For the fourth (and hopefully final) time as a tropical or
subtropical cyclone, Leslie has crossed 48W.  The convective pattern
of the tropical storm hasn't changed significantly over the past
several hours, though there is some evidence of a convective band
attempting to wrap around the western side of the storm.  The
initial intensity is still 45 kt, based on a blend of the most
recent current intensity estimates from TAFB, SAB, and the UW-CIMSS
SATCON.

There has been little change in the intensity forecast.  Just about
all of the typically reliable intensity models still call for
Leslie to gradually strengthen over the next 3 days, despite
marginal SSTs.  All of the dynamical models call for Leslie to
become a hurricane once again by 72 h, but SHIPS and LGEM
are a little lower.  The official intensity forecast remains near
the HCCA and IVCN consensus aids, and calls for Leslie to become a
hurricane by the end of the week.

Leslie has continued to move east-southeastward, now at 12 kt, and
the global models are in good agreement that this motion will
continue through today. After that time, most of the guidance
generally shows that Leslie will separate from a mid-latitude
trough, causing the tropical storm to turn toward the southeast or
south-southeast and slow down. A day or so after that, another
mid-latitude trough will approach from the west and cause Leslie to
accelerate toward the east-northeast.  The timing of Leslie's
acceleration is still very uncertain, and the model spread beyond
72 h remains very high.  Until the spread decreases, I don't feel
confident making a big change to the forecast, so the official track
forecast has only been slightly tweaked to bring it closer to HCCA
and TVCN.

FORECAST POSITIONS AND MAX WINDS

INIT  08/1500Z 34.6N  47.0W   45 KT  50 MPH
12H  09/0000Z 33.6N  45.2W   50 KT  60 MPH
24H  09/1200Z 32.0N  43.5W   50 KT  60 MPH
36H  10/0000Z 30.2N  42.2W   55 KT  65 MPH
48H  10/1200Z 29.1N  41.2W   60 KT  70 MPH
72H  11/1200Z 29.5N  37.0W   65 KT  75 MPH
96H  12/1200Z 33.0N  28.0W   70 KT  80 MPH
120H  13/1200Z 39.0N  18.0W   65 KT  75 MPH

$$
Forecaster Zelinsky