464
AXPZ20 KNHC 041551
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Sat Oct 4 2025

Tropical Weather Discussion for the eastern Pacific Ocean from
03.4S to 30N, east of 120W including the Gulf of California, and
from the Equator to 30N, between 120W and 140W. The following
information is based on satellite imagery, weather observations,
radar, and meteorological analysis.

Based on 1200 UTC surface analysis and satellite imagery through
1500 UTC.

...SPECIAL FEATURES...

Tropical Storm Octave is centered near 14.6N 123.6W at 04/1500
UTC, moving northwest at 6 kt, and a gradual turn toward the
north is expected tonight and tomorrow. Early next week, the
tropical storm is expected to turn northeastward and then
eastward. Estimated minimum central pressure is 1000 mb. Maximum
sustained wind speed is 50 kt with gusts to 60 kt. Slight
strengthening is possible during the next day or two. Peak seas
are 20 ft. Numerous moderate to strong convection is observed
within 120 nm SW semicircle.

Please read the latest NWS HIGH SEAS FORECAST issued by the
National Hurricane Center at website -
https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest
Octave NHC Forecast/Advisory and Public Advisory at
www.hurricanes.gov for more details.

Offshore of the Southwestern Coast of Mexico (EP99):
Showers and thunderstorms associated with a broad area of low
pressure a few hundred miles off the southwestern coast of Mexico
continue to become better organized this morning. If current
trends persist, advisories on a tropical depression could be
initiated later today or tonight. The system is forecast to move
slowly west-northwestward, remaining offshore of the southwestern
coast of Mexico during the next several days. Interests along
the southwestern coast of Mexico should continue to monitor the
progress of this system. For additional information, including
gale warnings, please see High Seas Forecasts issued by the
National Weather Service.

Please read the latest TROPICAL WEATHER OUTLOOK issued by the
National Hurricane Center at website -
https://www.nhc.noaa.gov/text/MIATWOEP.shtml and the latest NWS
HIGH SEAS FORECAST issued by the National Hurricane Center at
website - https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

The monsoon trough extends from 09N83W to 12N95W to low pressure
located near 15N105.5W, then resumes SW of Octave from 11N126W to
09N140W. Aside from the convection associated with Octave and
EP99, scattered moderate to isolated strong convection is noted from
07N to 13N between 90W and 100W.

...OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Please refer to the Special Features section for details on Invest
EP99 that has a high chance for tropical cyclone formation within
the next 48 hours. A Gale Warning is in effect for this system.

A ridge dominates the offshore forecast waters of Baja California
supporting moderate to fresh NW to N winds north of Cabo San
Lazaro and light to gentle winds between Cabo San Lazaro and Cabo
San Lucas. Light and variable winds and slight seas prevail in
the Gulf of California. Winds and seas are on increase across the
Mexican offshore forecast waters between Acapulco and Manzanillo
due to the presence of EP99. Fresh to strong northerly winds are
noted across the Tehuantepec region based on latest scatterometer
pass.

For the forecast, a ridge will continue to dominate the offshore
forecast waters of Baja California this weekend supporting
moderate to fresh NW to N winds N of Cabo San Lazaro, and gentle
to moderate winds between Cabo San Lazaro and Cabo San Lucas.
Marine conditions are forecast to deteriorate across the Mexican
offshore waters S of Cabo Corrientes this weekend due to a
developing tropical cyclone. Fresh to strong N to NE winds in
the Gulf of Tehuantepec will diminish below 20 kt later today.

Looking ahead, an area of low pressure is expected to form off
the southern coast of Mexico by the middle of next week. Gradual
development of this system is possible thereafter, and a tropical
depression could form during the middle to latter part of next
week while moving west-northwestward to northwestward, near or
parallel to the coast of Mexico. This system has a medium change
of tropical cyclone formation through 7 days.

...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA,
AND WITHIN 750 NM OF ECUADOR...

Unsettled weather conditions persist across the offshore waters
of Central America and Colombia. Meanwhile, a weak pressure
gradient continues to influence the region, sustaining gentle to
moderate S to SW winds S of the monsoon trough and light to
gentle winds to the N of it. Moderate seas in SW swell dominate
the area.

For the forecast, gentle to moderate southerly winds are expected
south of the monsoon trough into early next week. Southerly
swell will continue to propagate across the region, with a new
set of long period SW swell reaching the Galapagos Island tonight
into Sun. Light to gentle winds and moderate seas will persist
north of the monsoon trough.

...REMAINDER OF THE AREA...

Please refer to the Special Features section for details on
Tropical Storm Octave, and on Invest EP99 located offshore of SW
Mexico with the potential for tropical cyclone formation.

Outside of Octave, a surface trough is analyzed over the NW waters
and runs from 29N135W to 19N137W. Fresh NE to E winds and rough
seas are observed near the northern end of the trough axis due to
the pressure gradient between the trough and high pressure to
the N of the forecast region. High pressure dominates the
remainder of the area N of 20N W of 115W. Moderate to locally
fresh southerly winds are south of the monsoon trough W of 110W.
Moderate to rough seas are noted within these winds. Elsewhere,
moderate or lighter winds and moderate seas prevail.

For the forecast, Octave will move to 15.0N 124.1W this evening,
15.5N 124.1W Sun morning, 15.9N 123.5W Sun evening, 16.0N 122.6W
Mon morning, 16.0N 121.4W Mon evening, and 15.7N 120.2W Tue
morning. Octave will weaken to a tropical depression near 15.2N
118.0W early Wed. The area of NW swell will continue to spread
southward and weaken by Sun. Meanwhile, a new set of large southerly
swell will reach the equator today.

$$
GR