Tropical Storm Leslie Forecast Discussion

000
WTNT43 KNHC 102031
TCDAT3

Tropical Storm Leslie Discussion Number  34
NWS National Hurricane Center Miami FL       AL132024
500 PM AST Thu Oct 10 2024

The center of Leslie has been exposed for the past 6 h, thanks to 
strong northerly wind shear.  The center has continued to move 
farther away from the convection as the afternoon has progressed.  
The initial intensity is brought down to 60 kt, which agrees with a 
blend of the various objective intensity estimates from UW-CIMSS.

Leslie continues to plow through a zone of strong northerly shear, 
and the SHIPS guidance and model fields indicate Leslie will 
continue to experience 40 kt of northerly to northeasterly shear for 
another 12 to 24 h.  In addition, Leslie is forecast to continue 
moving through a relatively dry environment.  Rapid weakening is 
expected to continue over the next 12 to 24 h, and the latest NHC 
intensity forecast is lower than the previous one due to the weaker 
initial intensity.  If Leslie survives as a tropical cyclone for 
another two days, which is not guaranteed, it will approach a 
frontal zone in 2 to 3 days and could take on some frontal 
characteristics.  While all of the models show Leslie dissipating 
by 4 to 5 days, there is significant uncertainty on whether Leslie 
will become extratropical or just dissipate.

Leslie is moving northwestward, or 315/7 kt.  Model guidance is in 
good agreement that a northward turn will happen very soon as 
Leslie moves around the southwestern periphery of a subtropical 
ridge over the eastern Atlantic.  On Friday and Friday night, the 
hurricane should speed up and turn to the northeast, followed by an 
east-northeastward turn as it accelerates further over the weekend.  
There is a bit of along-track spread in the guidance after 48 h, as 
some of the models show Leslie accelerating faster toward the 
east-northeast.  Only minor changes are made to the previous NHC 
track to account for the models being slightly farther west during 
the first 36 h of the forecast.


FORECAST POSITIONS AND MAX WINDS

INIT  10/2100Z 23.9N  50.9W   60 KT  70 MPH
 12H  11/0600Z 24.9N  51.1W   45 KT  50 MPH
 24H  11/1800Z 27.0N  50.1W   40 KT  45 MPH
 36H  12/0600Z 29.6N  47.6W   40 KT  45 MPH
 48H  12/1800Z 32.5N  43.3W   40 KT  45 MPH
 60H  13/0600Z 34.8N  38.2W   40 KT  45 MPH...POST-TROPICAL
 72H  13/1800Z 36.1N  32.8W   40 KT  45 MPH...POST-TROPICAL
 96H  14/1800Z 36.0N  23.5W   30 KT  35 MPH...POST-TROPICAL
120H  15/1800Z...DISSIPATED

$$
Forecaster Hagen