927
WTPZ45 KNHC 032035
TCDEP5

Tropical Storm Octave Discussion Number  15
NWS National Hurricane Center Miami FL       EP152025
200 PM PDT Fri Oct 03 2025

While Octave`s overall appearance has remained steady since this
morning, its center appears to be just embedded enough within the
central dense overcast produced by its convection for recent
subjective Dvorak estimates to come up to T3.5 or 55 kt. Objective
intensity estimates are still a little lower, so the intensity has
been nudged up slightly to 50 kt for this advisory. There was no
useful ASCAT data available for this afternoon`s analysis, but
earlier SAR data also generally supported an intensity near 50 kt
with wind radii similar to what NHC previously analyzed.

No changes of note were made to the NHC track or intensity
forecasts, but both aspects of the forecast remain highly uncertain,
especially beyond the next 24 hours. Octave should still continue
west-northwestward for another day or so, before it slows down and
turns northward. Next week Octave will likely begin moving slowly
eastward, but exactly how fast and how far north it moves before
will depend on how much Octave interacts with a trough well to its
north and a large disturbance developing to its east. The NHC track
forecast is still near the middle of the multi-model and
single-model ensemble envelopes but confidence in the forecast has
not increased, especially beyond 72 hours.

Similarly, Octave`s intensity will probably change little for the
next 12 to 24 hours. After that, it will have a brief period of a
day or so where the shear is expected to lessen and the cyclone
could intensity further. The Google DeepMind Ensemble Mean continues
to be an outlier in showing Octave reaching hurricane strength, but
the ensemble shows that there is a wide range of possibilities from
a near steady-state tropical storm to a strong hurricane. The
official forecast is still on the high end of the other intensity
guidance, but is lower than the GDM mean. By the end of the
forecast period, Octave will likely weaken as it interacts with the
much larger disturbance currently located to its east.


FORECAST POSITIONS AND MAX WINDS

INIT  03/2100Z 13.7N 121.7W   50 KT  60 MPH
 12H  04/0600Z 14.1N 122.8W   50 KT  60 MPH
 24H  04/1800Z 14.7N 123.7W   50 KT  60 MPH
 36H  05/0600Z 15.2N 124.1W   55 KT  65 MPH
 48H  05/1800Z 15.6N 123.8W   55 KT  65 MPH
 60H  06/0600Z 15.7N 123.4W   50 KT  60 MPH
 72H  06/1800Z 15.7N 122.5W   50 KT  60 MPH
 96H  07/1800Z 15.2N 120.5W   40 KT  45 MPH
120H  08/1800Z 15.0N 118.0W   35 KT  40 MPH

$$
Forecaster D. Zelinsky