WTPZ43 KNHC 271435

TCDEP3

 

Tropical Storm Sonia Discussion Number  12

NWS National Hurricane Center Miami FL       EP182025

800 AM PDT Mon Oct 27 2025

 

Satellite images show that the low-level center is exposed, with

southerly wind shear causing convection to be displaced to the

north. Satellite intensity estimates range between 35 to 45 kt,

thus the initial intensity is held at 40 kt for this advisory.

 

The system looks to have turned back towards the west at an 

estimated motion of 275/6 kt. This general motion should continue as 

the system weakens and becomes more shallow, and steered by the 

low-level wind flow. The NHC track was nudged slightly south 

towards the HCCA corrected consensus and Google DeepMind solution.

 

Sonia is moving into an increasingly unfavorable environment. Wind 

shear is expected to increase, with cooling SSTs, and drier air  

along the forecast track. This should lead to a gradual weakening 

trend, and model simulated IR satellite shows convection diminishing 

by Tuesday. The latest NHC forecast follows these trends with the 

system becoming a post-tropical remnant low in 36 h. The system is 

forecast to dissipate and open into a trough in two to three days.

  

FORECAST POSITIONS AND MAX WINDS

 

INIT  27/1500Z 13.8N 121.1W   40 KT  45 MPH

 12H  28/0000Z 13.9N 122.0W   40 KT  45 MPH

 24H  28/1200Z 14.1N 123.4W   35 KT  40 MPH

 36H  29/0000Z 14.2N 124.9W   30 KT  35 MPH...POST-TROPICAL

 48H  29/1200Z 14.2N 126.7W   30 KT  35 MPH...POST-TROP/REMNT LOW

 60H  30/0000Z 14.0N 128.6W   25 KT  30 MPH...POST-TROP/REMNT LOW

 72H  30/1200Z...DISSIPATED

 

$$

Forecaster Kelly