202
AXPZ20 KNHC 192120
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Sat Oct 19 2024

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 1800 UTC surface analysis and satellite imagery through
2100 UTC.

...SPECIAL FEATURES...

Gulf of Tehuantepec Gale Warning: A ridge across the eastern slopes
of the Sierra Madre Mountains in Mexico will continue to support
gale force winds in the 30 to 40 kt range across the Tehuantepec
region through early Sun morning. Seas are forecast to build to
14 or 15 ft tonight within these wind speeds. Seas generated
from this gap wind event will spread well away from the Tehuantepec
area, with seas 8 ft or greater reaching as far south as 08N on
Sun morning. Marine interests transiting across the Gulf of
Tehuantepec this weekend should be aware of this gap wind event,
and take the necessary action to avoid hazardous marine conditions
over the affected waters. Looking ahead, after tropical cyclone
Nadine dissipates over southern Mexico, its remnants are expected
to move into the eastern Pacific. The combination of the remnants
of Nadine and influences from the Gulf of Tehuantepec gap wind
event are forecast to result in the formation of a new low pressure
system off the coast of southwestern Mexico in a couple of days.
As a result, fresh to strong winds are expected to persist in
the Tehuantepec region through at least Tue.

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

The monsoon trough extends from 10N86W to 08N100W to a 1012 mb
low pressure centered near 14N116W to 11N125W to 12N140W.
Clusters of moderate to strong convection are noted over parts of
Panama and the Gulf of Panama, mainly N of 06N between 78W and
81W. Scattered moderate convection is noted from 07N to 11N
between 100W and 111W, and from 09N to 13N between 115W and 132W.

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

A Gale Warning remains in effect for the Gulf of Tehunatepec.
Please see the Special Features section for more details.

A 1027 mb high pressure located N of area near 36N135W extends a
ridge across the waters west of Baja California while a frontal
boundary is analyzed over the central Gulf of California and a
trough extends through central Mexico. The pressure gradient
between these features is supporting gentle to moderate NW winds
over the waters offshore of Baja California, with moderate NW
winds near Cabo San Lucas. Seas are 4 to 7 ft N of Cabo San
Lazaro and 3 to 5 ft between Cabo San Lucas and Cabo San Lazaro.
Gentle to locally moderate NW winds and seas of 1 to 3 ft are
observed in the Gulf of California. Elsewhere away from the gale
force winds in the Gulf of Tehuantepec, light to gentle winds and
slight to moderate seas in NW swell prevail across the remainder
of the Mexican offshore waters.

For the forecast, gale force winds are expected in the Gulf of
Tehuantepec through early Sun Morning, then fresh to strong winds
will persist through at least Tue. Seas are forecast to build to
14 or 15 ft tonight within the strongest winds. Ridging will
prevail over the offshore waters while a trough will meander
between the Gulf of California and Baja California. This pattern
will promote gentle to moderate NW winds across the offshore
forecast waters of Baja California, and moderate to fresh NW
winds across the central and southern parts of the Gulf of
California through Tue. Looking ahead, after tropical cyclone
Nadine dissipates over southern Mexico, its remnants are expected
to move into the eastern Pacific. The combination of the
remnants of Nadine and influences from the Gulf of Tehuantepec
gap wind event are forecast to result in the formation of a new
low pressure system off the coast of southwestern Mexico in a
couple of days. Additional development is expected after that
time, and a tropical depression is likely to form during the
early to middle part of next week while the system moves westward
at about 10 to 15 kt away from the coast of Mexico. This system
has a low chance of tropical cyclone development through 48
hours, and a high chance through the next 7 days.

Please, read the latest NHC Tropical Weather Outlook at
www.hurricanes.gov for more details.

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

Once again, scatterometer satellite data show gentle to locally
moderate S to SW winds south of the monsoon trough, and light to
gentle winds to the north. Seas are generally 3 to 5 ft in the
offshore waters of Central and South America, except in the lee
of the Galapagos Islands, where wave heights are 1 to 3 ft.

For the forecast, gentle to moderate S to SW winds will occur
south of the monsoon trough while light to gentle winds will
prevail to the north. Seas generated in the Tehuantepec region
will propagate across the outer offshore waters of Guatemala and
El Salvador through Sun, with seas likely building to 8 to 12
ft. Then, seas are forecast to subside to 5 to 7 ft in this area
on Mon. Elsewhere, mainly moderate seas in cross equatorial SW
swell are expected, with the highest seas, in the 5 to 7 ft
range, between Ecuador and the Galapagos Islands.

...REMAINDER OF THE AREA...

High pressure dominates the forecast waters N of 15N and W of
110W producing gentle to moderate winds N of the monsoon trough
and W of 120W, and mainly light to gentle winds between 110W and
120W. Seas are generally 5 to 7 ft based on altimeter data,
except 8 to 10 ft in NW swell N of 26N between 120W and 126W.
Seas of 8 to 10 ft are also noted per altimeter data S of the
Equator between 105W and 120W in cross equatorial SW swell.
Elsewhere, gentle to moderate winds and moderate seas prevail.

For the forecast, the high pressure will move SW and weaken as a
cold front approaches from the west. The cold front will approach
30N140W on Mon and become stationary. A low pressure may form
along the frontal boundary on Tue, with a cold front reaching the
NW corner of the forecast region by Tue night. A swell event is
forecast to follow the front. Rough seas north of 26N will
slowly subside tonight.

$$
GR