000
WTPZ43 KNHC 262050
TCDEP3
 
Tropical Storm Sonia Discussion Number   9
NWS National Hurricane Center Miami FL       EP182025
200 PM PDT Sun Oct 26 2025
 
Visible satellite imagery and a recent ASCAT-B scatterometer pass 
show that the low-level center was slightly further east than the 
previous advisory, on the southeastern side of the convection. 
Convection has been waning over the last few hours, with warming 
cloud tops. The latest satellite intensity estimates range from 30 
to 44 kt, and the peak satellite derived winds from ASCAT-B were 36 
kt. Using this data, the initial intensity is held at 40 kt for this 
advisory. The wind radii have been adjusted and refined with the 
scatterometer data.
 
Sonia is moving slowly west-northwestward at an estimated motion of 
295/03 kt. This west-northwest motion at a slightly faster forward 
speed is anticipated over the next day or so. Once the system begins 
to weaken, the storm will turn back towards the west steered by the 
low-level wind flow. The latest NHC track forecast lies near the 
previous, between the HCCA corrected consensus and Google DeepMind 
aids.
 
Sonia continues to deal with moderate southerly wind shear, which 
will increase over the next couple of days. The latest sea surface 
temperature analysis shows that the system is moving into sub 27C 
ocean temperatures, with even cooler SSTs, and a drier more stable 
airmass along the forecast track. Given the latest satellite trends 
and the less than favorable environmental conditions, intensity aids 
show a gradual weakening trend. The GFS and ECMWF model simulated IR 
satellite shows that the system will struggle to produce enough 
convection to be categorized as a tropical system by 60h. The latest 
NHC intensity forecast follows these trends and lies near the 
consensus aids, becoming a remnant low in 60h and then dissipating 
by day 4.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  26/2100Z 13.8N 119.8W   40 KT  45 MPH
 12H  27/0600Z 14.1N 120.3W   40 KT  45 MPH
 24H  27/1800Z 14.3N 121.4W   35 KT  40 MPH
 36H  28/0600Z 14.5N 122.6W   35 KT  40 MPH
 48H  28/1800Z 14.7N 124.0W   30 KT  35 MPH
 60H  29/0600Z 14.7N 125.7W   25 KT  30 MPH...POST-TROP/REMNT LOW
 72H  29/1800Z 14.5N 127.8W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  30/1800Z...DISSIPATED
 
$$
Forecaster Kelly