Subtropical Storm Patty Forecast Discussion

000
WTNT42 KNHC 022032
TCDAT2

Subtropical Storm Patty Discussion Number   3
NWS National Hurricane Center Miami FL       AL172024
900 PM GMT Sat Nov 02 2024

Patty has not changed much during the past several hours. The storm 
has been maintaining a small core, though the cloud tops are not as 
cold as they were earlier today. The system is still co-located with 
an upper-level low and dry and stable air continues to wrap around 
the core region. These mixed tropical and extratropical 
characteristics continue to support Patty's subtropical designation. 
The initial intensity is held at 55 kt based on the earlier ASCAT 
data, but this is above the latest satellite estimates. Patty is 
located about 60 n mi south of the westernmost Azores, and it will 
be passing near the central and eastern Azores later tonight and 
Sunday.

Weakening should begin soon as the parent upper-level low weakens, 
leaving the storm in more stable conditions and stronger vertical 
wind shear. The models suggest that the low could lose its core and 
deep convection by late Sunday, which should cause it to become a 
post-tropical cyclone in 24 to 36 hours. Additional weakening is 
expected after that, and the storm will likely dissipate in 3 to 4 
days.

The subtropical storm is accelerating southeastward, and the latest 
initial motion estimate is 125/16 kt. An eastward motion is expected 
to begin overnight, taking Patty near or just south of the Azores 
through Sunday. An east-northeastward motion is expected after that 
toward western Europe. The models are in fairly good agreement, and 
this forecast remains near the middle of the guidance envelope.

Key Messages:

1. Tropical storm conditions are expected in the Azores through 
Sunday, where Tropical Storm Warnings are in effect.

2. Locally heavy rains are possible across the Azores through
Sunday.


FORECAST POSITIONS AND MAX WINDS

INIT  02/2100Z 38.0N  30.1W   55 KT  65 MPH
 12H  03/0600Z 37.5N  27.0W   50 KT  60 MPH
 24H  03/1800Z 37.3N  23.1W   45 KT  50 MPH
 36H  04/0600Z 37.8N  19.0W   40 KT  45 MPH...POST-TROPICAL
 48H  04/1800Z 39.0N  14.8W   35 KT  40 MPH...POST-TROPICAL
 60H  05/0600Z 40.5N  11.4W   30 KT  35 MPH...POST-TROP/REMNT LOW
 72H  05/1800Z 41.7N   9.8W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  06/1800Z...DISSIPATED

$$
Forecaster Cangialosi