Tropical Cyclone Discussion
Issued by NWS

Home |  Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
115
WTPZ45 KNHC 072039
TCDEP5

Tropical Storm Octave Discussion Number  31
NWS National Hurricane Center Miami FL       EP152025
200 PM PDT Tue Oct 07 2025

Octave continues to produce clusters of deep convection, though this
activity is becoming more fragmented and displaced southwest of the
now exposed low-level center. This structure is largely the result
of increasing east-northeasterly shear related to much larger
Hurricane Priscilla to the northeast. While the subjective Dvorak
estimates remain T3.0/45-kt, the objective intensity estimates are
now all under 40 kt, and a recent scatterometer pass only had a peak
derived wind of 37 kt. Thus, the initial intensity for Octave is
lowered to 40 kt this advisory.

Now that the center is mostly exposed, its been a little easier to
track the center, with its motion estimated east-southeastward at
110/7 kt. Octave`s primary steering currents are low to mid-level
westerlies that are partially related to the circulation of
Priscilla and the larger monsoonal flow that has developed across
the eastern Pacific. As the storm reaches Priscilla`s longitude,
Octave`s track will likely bend more poleward as it rounds the outer
edge of Priscilla`s flow. The latest NHC track forecast is
close to the prior one, but is a little faster after 24 h, following
the latest trends in the HCCA and Google DeepMind guidance.

The current 20-25 kt of vertical wind shear is expected to increase
further to 30-35 kt over the next 24-36 h. Thus, Octave is expected
to continue weakening, but will likely to continue to produce
sheared bursts of deep convection as it continues to traverse warm
sea-surface temperatures. After 48 hours, most of the guidance shows
the cyclone degenerating into a trough, roughly between Priscilla to
its northwest and another developing system (EP90) to its southeast.
The NHC intensity forecast is a bit lower than earlier, and now
shows dissipation in 60 h, though this could occur sooner than shown
here given the hostile environmental conditions. This forecast is
roughly in the middle of the model consensus.


FORECAST POSITIONS AND MAX WINDS

INIT  07/2100Z 15.3N 118.8W   40 KT  45 MPH
 12H  08/0600Z 15.2N 117.7W   40 KT  45 MPH
 24H  08/1800Z 15.7N 115.6W   35 KT  40 MPH
 36H  09/0600Z 16.6N 113.1W   30 KT  35 MPH
 48H  09/1800Z 17.4N 110.5W   25 KT  30 MPH
 60H  10/0600Z...DISSIPATED

$$
Forecaster Papin