Tropical Storm Leslie Discussion Number   4
NWS National Hurricane Center Miami FL       AL132024
500 AM AST Thu Oct 03 2024

The satellite structure of Leslie has changed little since the 
previous advisory, with small curved bands of convection primarily 
on the eastern side of the storm. Upper-level outflow from distant 
Hurricane Kirk continues to impinge on the western portion of the 
circulation. The initial intensity is held at 35 kt, in best 
agreement with a T2.5/35-kt TAFB subjective Dvorak classification.

Leslie is moving slowly westward (265/5 kt) to the south of a 
subtropical ridge over the eastern Atlantic. A gradual turn to the 
west-northwest and northwest, along with a slight increase in 
forward speed, is forecast on Friday and over the weekend while the 
storm moves around the western extent of the ridge. The models are 
in reasonably good agreement on this scenario through the 5-day 
forecast period. The updated NHC prediction is virtually unchanged 
from the previous one, and lies near or in between the multi-model 
consensus aids HCCA and TVCA.

As the distance between Kirk and slow-moving Leslie grows, the wind 
shear over Leslie should diminish. This will provide a more 
conducive environment for the storm to steadily strengthen within a 
moist environment over warm waters. There is some spread in the 
intensity guidance regarding how much strengthening will occur 
during the next 2-3 days, with the HAFS-A/B models much higher than 
the global models and statistical-dynamical aids. Given the storm's 
current structure and slow forward speed, the NHC forecast remains 
near the middle of the guidance envelope, closest to the IVCN simple 
consensus aid. This forecast brings Leslie to hurricane strength by 
early Saturday. As previously noted, the intensity of Leslie could 
plateau thereafter if it follows a similar track to Kirk and 
encounters the cool wake left behind by the hurricane.


FORECAST POSITIONS AND MAX WINDS

INIT  03/0900Z 10.3N  30.5W   35 KT  40 MPH
12H  03/1800Z 10.1N  31.2W   40 KT  45 MPH
24H  04/0600Z 10.2N  32.3W   50 KT  60 MPH
36H  04/1800Z 10.5N  33.6W   60 KT  70 MPH
48H  05/0600Z 11.1N  35.0W   70 KT  80 MPH
60H  05/1800Z 11.8N  36.4W   80 KT  90 MPH
72H  06/0600Z 12.7N  37.6W   85 KT 100 MPH
96H  07/0600Z 15.3N  40.4W   85 KT 100 MPH
120H  08/0600Z 18.0N  44.0W   90 KT 105 MPH

$$
Forecaster Reinhart