Official Discussion issued by the National Hurricane Center

Leslie (AL132018) DATA RELEASED: 10/11/2018 5:00:00 PM UTC

Copy of official data

Hurricane Leslie Discussion Number  62
NWS National Hurricane Center Miami FL       AL132018
500 PM AST Thu Oct 11 2018

Leslie's inner-core structure has improved a little during the day
today.  A ragged banding eye was present in visible imagery until
sunset, though this feature is not apparent in IR imagery. Recent
satellite intensity estimates range from 65 kt to 90 kt, so Leslie's
intensity has been raised to 75 kt as a compromise of all available
estimates.

Leslie continues to accelerate east-northeastward with an initial
motion estimate of 065/18 kt. Confidence remains high that Leslie
will continue gaining speed on that heading for the next 24 h or
so. Beyond that time, the ensemble spread is still very high,
though the 12Z deterministic global models are generally in
agreement that Leslie will separate from a mid-level trough, slow
down, and turn southward over the weekend. While the exact timing of
this turn is still highly uncertain, the multi-model consensus
brings Leslie near Madeira Island on Saturday as a tropical storm.
The new official forecast shows a very similar track, and the
government of Portugal has issued a Tropical Storm Watch for that
island. While the exact path of Leslie is still uncertain, the
cyclone is still expected to produce tropical storm conditions over
a wide area through Saturday, and interests on Madeira should not
focus on the exact track of Leslie.

No large changes in intensity are anticipated during the next 24 h,
though some fluctuations are possible, up or down. By 36 h, Leslie
will reach much cooler waters and encounter an increase in wind
shear which should lead to steady weakening. The intensity guidance
is in surprisingly good agreement given the continued large track
spread, and the NHC intensity forecast is near the middle of the
guidance envelope from 36 h onward. By 96 h, odds are increasing
that Leslie could lose all of its convection and become
post-tropical, though this possibility still depends heavily on
Leslie following a track similar to the NHC official forecast.

FORECAST POSITIONS AND MAX WINDS

INIT  11/2100Z 29.9N  36.5W   75 KT  85 MPH
12H  12/0600Z 31.0N  33.0W   75 KT  85 MPH
24H  12/1800Z 32.5N  27.4W   75 KT  85 MPH
36H  13/0600Z 33.3N  21.6W   65 KT  75 MPH
48H  13/1800Z 33.1N  17.4W   55 KT  65 MPH
72H  14/1800Z 30.9N  16.0W   40 KT  45 MPH
96H  15/1800Z 29.0N  18.5W   30 KT  35 MPH...POST-TROPICAL
120H  16/1800Z 28.0N  24.0W   30 KT  35 MPH...POST-TROP/REMNT LOW

$$
Forecaster Zelinsky