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693
WTPZ45 KNHC 052046
TCDEP5

Hurricane Octave Discussion Number  23
NWS National Hurricane Center Miami FL       EP152025
200 PM PDT Sun Oct 05 2025

The structure of Octave has changed little since the previous
advisory. The low-level center continues to be underneath the
eastern side of the tightly wound curved banding, associated with
the core of the hurricane.  There continues to be hints of an eye
in visible satellite imagery.  Subjective Dvorak estimates are a
consensus 65 kt from TAFB and SAB, while objective intensity
estimates range from 55-80 kt.  The initial intensity is held at 70
kt.

The initial motion estimate is slightly faster toward the northeast,
or 055 degrees at 5 kt.  A turn toward the east at a slightly faster
forward speed is expected Monday as the cyclone is pushed in that
direction by an upper-level trough to its northwest.  By early
Tuesday, the main weather feature affecting Octave`s track will
likely be a large and powerful Priscilla, which should cause Octave
to turn toward the east-southeast.  By Wednesday, models are in
agreement that Octave should be located south of Priscilla.  Once
Octave gets southeast of Priscilla, an acceleration toward the
northeast is expected until Octave`s circulation likely dissipates
in a little less than 4 days.  The NHC forecast has been adjusted
slightly to the north of the previous official forecast through 60
hours, and lies roughly in between the latest GFEX and the Google
Deep Mind Ensemble mean.

Octave is straddling the sea-surface temperature (SST) gradient and
is forecast to move parallel to the SST gradient for the next couple
of days, with the eye likely to encounter SSTs in the 26 to 26.5
degree C range.  Wind shear should remain relatively low through the
next 24-36 hours.  Octave is forecast to gradually encounter a
slightly drier and more stable airmass on Monday.  All of the models
show Octave weakening beginning shortly, but given the environmental
conditions, it wouldn`t be surprising to see the cyclone maintain
its intensity for another 12-24 h.  The NHC intensity forecast is
near the high end of the model guidance for the first 24 h, then
lies near the middle of the guidance envelope thereafter.  By 36 h,
increasing easterly shear, partially the result of the outflow from
Priscilla, is expected to lead to weakening.  Model guidance
suggests that either Octave will be absorbed by the stronger
Priscilla or that the outflow from Priscilla will disrupt Octave`s
circulation, opening it into a trough.  Regardless of which scenario
occurs, Octave should dissipate within 4 days.


FORECAST POSITIONS AND MAX WINDS

INIT  05/2100Z 16.0N 123.3W   70 KT  80 MPH
 12H  06/0600Z 16.2N 122.5W   65 KT  75 MPH
 24H  06/1800Z 16.3N 121.3W   60 KT  70 MPH
 36H  07/0600Z 16.1N 120.2W   55 KT  65 MPH
 48H  07/1800Z 15.7N 119.1W   50 KT  60 MPH
 60H  08/0600Z 15.5N 117.9W   50 KT  60 MPH
 72H  08/1800Z 15.8N 115.9W   45 KT  50 MPH
 96H  09/1800Z...DISSIPATED

$$
Forecaster Hagen