WTPZ43 KNHC 270239

TCDEP3

 

Tropical Storm Sonia Discussion Number  10

NWS National Hurricane Center Miami FL       EP182025

800 PM PDT Sun Oct 26 2025

 

Satellite imagery indicates that Sonia has degraded during the past 

12 to 24 h as persistent moderate southerly wind shear has displaced 

deep convection mostly north of the low-level circulation center. 

The circulation is now partially exposed on the southern edge of the 

deep convection. Based on a blend of the subjective Dvorak and 

objective intensity estimates, the initial intensity is set at 40 

kt.

 

Sonia is moving west-northwestward at about 295/5 kt, and this 

general motion is expected to persist over the next day or so, as 

the subtropical ridge remains positioned to the north. By Tuesday, 

Sonia should gradually turn toward the west as it becomes a shallow 

system embedded within the low-level trade-wind flow. The NHC track 

forecast is little changed from the previous one and remains close 

to the multi-model consensus aids.



Moderate southerly wind shear continues to affect Sonia and is 

expected to generally hold steady during the next couple of days, if 

not increase slightly. This, combined with cooler waters and a 

drier, more stable environment ahead of the cyclone, should result 

in a gradual weakening trend beginning within the next 12 to 24 

hours. Simulated satellite imagery from the GFS and ECMWF shows 

convection diminishing significantly by Tuesday, suggesting that 

Sonia will lose organized deep convection and become a post-tropical 

remnant low by that time. Dissipation is expected by Wednesday as 

the remnant low continues westward and opens into a trough. The 

updated NHC intensity forecast closely follows the consensus aids 

and remains similar to the previous one.

 

 

FORECAST POSITIONS AND MAX WINDS

 

INIT  27/0300Z 14.1N 120.0W   40 KT  45 MPH

 12H  27/1200Z 14.3N 120.6W   40 KT  45 MPH

 24H  28/0000Z 14.6N 121.7W   35 KT  40 MPH

 36H  28/1200Z 14.8N 123.2W   35 KT  40 MPH

 48H  29/0000Z 14.8N 124.7W   30 KT  35 MPH...POST-TROP/REMNT LOW

 60H  29/1200Z 14.7N 126.6W   25 KT  30 MPH...POST-TROP/REMNT LOW

 72H  30/0000Z...DISSIPATED

 

$$

Forecaster Gibbs (CPHC)