361
AXPZ20 KNHC 170925
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Tue Sep 17 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 0600 UTC surface analysis and satellite imagery through
0830 UTC.

...TROPICAL WAVES...

The southern portion of a tropical wave is along 90W extending
from Guatemala southward over the eastern Pacific to near 07N,
moving westward at 10 kt. isolated moderate convection is
occurring over the Pacific waters within 180 nm of this wave.

A tropical wave is along 107W from offshore of Cabo Corrientes
to near 07N, moving westward at about 10 kt. A lone cluster of
moderate convection is occurring along the base of the wave where
it intersects with the monsoon trough.

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

The monsoon trough extends from 11.5N73.5W to 10.5N86W to 08N93W
to 11N102W to 10N120W. The ITCZ extends from 10N120W to 11N130W
to beyond 09N140W. Scattered moderate to strong convection is
seen N of 03N and E of 83W, within 60 nm of the Mexican coast
from 94W to 101W, from 8.5N to 11.5N between 98W and 106W, within
75 nm N of a line from 15N109W to 12N120W to 10N122W, and from
08N to 12N between 125W and 136W.

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

Gentle to moderate S to SW winds prevail across the central Gulf
of California, in the wake of Ileana, whose remnants are now
across northern Sonora. Seas there are 3 ft or less. A narrow
plume of fresh to strong SW gap winds extends northeastward
across the northern Gulf from the coast along Campo Huerfanito to
near La Choya, where recent scatterometer data showed winds 20 to
30 kt. Seas there are 4 to 7 ft, while winds and seas are lower
on either side. Elsewhere, light and variable winds prevail
across the southern Gulf south of 24.5N, where seas are 2 to 3
ft.

A persistent broad and weak ridge extends southeastward into the
area waters tonight. The resultant pressure gradient is
producing gentle to moderate NW winds across the near and
offshore waters of Baja California, and extend to Cabo Corrientes
and the Revillagigedo Islands. Winds have increased to fresh
tonight along the coast of Baja Norte. Seas across these area
waters are generally 4 to 5 ft except to 6 ft across the waters
NW of Isla Guadalupe. Generally, light NW to W winds dominate
the waters from Manzanillo to the Tehuantepec region where seas
are 4 to 5 ft in southerly swell east of 103W, and with mixed NW
and S swell west of 103W. Scattered moderate to strong
thunderstorms continue across the nearshore waters within 75 nm
of the coast from Tehuantepec to Zihauntanejo.

For the forecast, fresh to strong SW gap winds will weaken
through morning as a dying cold front moves into the far northern
Gulf, allowing fresh to strong N winds to briefly spill into the
northern basin. Elsewhere, broad high pressure northwest of the
area supporting gentle to moderate northerly winds across the
Baja offshore waters will strengthen slightly tonight through
Wed morning, leading to a slight increase in seas. Winds will
pulse to fresh during the afternoons and evenings off the Baja
California coast through Wed. A dying cold front will sink into
the northern waters Thu and early Fri and act to weaken the
ridge ahead of it.

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

Moderate to fresh NE gap winds prevail across the Papagayo
region tonight, where seas are 4 to 5 ft. Elsewhere Light and
variable winds prevail across the regional waters north of 09N.
Seas there range 4 to 5 ft in south swell. S of 09N, gentle to
moderate southwest to west winds prevail. Seas are 4 to 6 ft in
south to southwest swell there, except 2 to 3 ft inside the Gulf
of Panama. Thunderstorms across Colombia have shifted into the
adjacent waters tonight, and cover the Colombian waters N of 03N
extending into the Gulf of Panama, and the coastal waters of
western Panama.

For the forecast, gentle to moderate southwest to west winds
will continue south of the monsoon trough through Tue, then
freshen modestly Wed through Fri, leading to a modest increase in
seas. North of the trough, light to gentle winds are expected
through Thu. The moderate to fresh gap winds across the Papagayo
region will become gentle to moderate east winds today before
shifting SE tonight. Moderate seas in primarily southwest swell
will continue through Wed before increasing Wed night through
Fri, with little change expected afterward.

...REMAINDER OF THE AREA...

A 1030 mb high continues across the NE Pacific along 153W,
extending a broad ridge southward into the region, dominating the
area north of the ITCZ and west of about 115W. The related
pressure gradient is producing generally moderate northeast
trades W of 128W, except W of 135W where fresh trades are
occurring due to a weak low level trough shifting westward across
that area. Seas there are 7 to 8 ft in NE swell west of 136W,
while seas over the rest of the area are 5 to 7 ft in mixed
swell. Moderate to fresh S to SE winds continue south of the
ITCZ W of 130W, with gentle to moderate winds elsewhere south of
the monsoon trough. Seas are 5 to 7 ft south of the monsoon
trough, and 4 to 7 ft east of 120W.

For the forecast, the aforementioned high pressure will drift W
through Wed, then reorganize to the NE Thu and Fri, with the
associated ridge changing little. This will result in moderate to
fresh trades south of 20N and west of 130W, and seas 6 to 8 ft
in NE swell through Wed morning. Winds will become moderate to
locally fresh S of 23N Wed through Fri. Moderate to fresh SW to
W winds and mostly seas of 4 to 7 ft are expected elsewhere south
of the monsoon trough through Wed night before a modest increase
E of 110W Thu and Fri.

$$
Stripling