Official Discussion issued by the National Hurricane Center

Leslie (AL132018) DATA RELEASED: 10/1/2018 5:00:00 PM UTC

Copy of official data

Tropical Storm Leslie Discussion Number  22
NWS National Hurricane Center Miami FL       AL132018
500 PM AST Mon Oct 01 2018

The cloud pattern of Leslie has improved throughout the day, and
the system now has a ragged eye with multiple mesovorticies within
it.  In addition, the associated convection has become more
symmetric this afternoon, but the cloud tops are not very cold south
of the center.  Even though the system looks better organized, the
satellite intensity estimates are again unchanged.  Accordingly, the
initial intensity is held at 50 kt near the high end of the
satellite estimates.

Leslie will likely strengthen gradually during the next day or
so as it heads toward slightly warmer SSTs and remains in relatively
low wind shear conditions.  Most of the models show Leslie
becoming a hurricane on Tuesday, and the NHC forecast follows that
guidance.  Leslie is expected to move north-northeastward back over
its own upwelled cool waters late this week and this weekend,
which should promote a gradual weakening trend.  The NHC intensity
forecast is identical to the previous one and in line with the HCCA
and IVCN models.

Leslie continues to drift to the southwest on the east side of a
mid-level high.  There has been no change to the track forecast
philosophy.  Leslie is expected to continue to move slowly southward
to southwestward in weak steering currents during the next couple of
days.  Thereafter, a developing shortwave trough to the west of
Leslie should cause it to move north-northeastward to northeastward
at a slightly faster pace.  The guidance has shifted south and west
this cycle, and the NHC track forecast has been adjusted in those
directions.  Regardless of the details of the forecast track, there
is high confidence that Leslie will meander for quite a while over
the central Atlantic.

Large swells generated by Leslie will continue to affect portions
of the southeastern coast of the United States, Bermuda, the
Bahamas, and most of the Greater and Lesser Antilles through
tonight.  These swells could cause life-threatening surf and rip
currents.  Although the swells will diminish slightly by Tuesday,
they are expected to increase again over the Bahamas and most of the
Greater and Lesser Antilles late Wednesday and Thursday.


FORECAST POSITIONS AND MAX WINDS

INIT  01/2100Z 32.8N  54.6W   50 KT  60 MPH
12H  02/0600Z 31.9N  55.4W   55 KT  65 MPH
24H  02/1800Z 30.9N  55.9W   65 KT  75 MPH
36H  03/0600Z 30.2N  56.2W   70 KT  80 MPH
48H  03/1800Z 30.0N  56.4W   70 KT  80 MPH
72H  04/1800Z 33.3N  55.8W   65 KT  75 MPH
96H  05/1800Z 36.4N  55.0W   60 KT  70 MPH
120H  06/1800Z 37.2N  52.8W   60 KT  70 MPH

$$
Forecaster Cangialosi