022
AXPZ20 KNHC 160914
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Mon Sep 16 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
0800 UTC.

...TROPICAL WAVES...

A tropical wave is along 104W from southwest Mexico to 08N,
moving W at 10 kt. Widely scattered small clusters of moderate
convection are noted along the Mexican coast and along the
monsoon trough between 98W and 105W.

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

The monsoon trough extends from 11N73.5W to 10.5N87W to 09N94W to
11N101W to 08.5N120W, where it transitions to ITCZ continuing on
to 06N131W. Another segment of ITCZ extends from low pressure
1011 mb near 15.5N127W to 12N133W to beyond 12N140W. Scattered
moderate to strong convection is noted from 06N to beyond 10N and
into the Caribbean between 78W to 85W. Scattered moderate
convection is noted from 09N northward to the coasts between 86W
and 94W. Scattered moderate isolated strong convection is noted
within 90 nm of the trough between 98W and 118W. Scattered
moderate to strong convection is seen from 06N to 09N between
120W and 133W.

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

Post-Tropical Cyclone Ileana continues to move slowly
northwestward across the Gulf of California, and is located near
26.5N110.5W in the central Gulf of California. Scattered showers
are noted within 30 nm north and 90 nm south of the center, while
a lone thunderstorm has recently develop within 15 nm south of
center. Peak winds of 15 to 20 kt are assumed to still be
occurring within 60 nm across the eastern semicircle, where
maximum seas are to 5 ft. This system will continue to move
slowly NW and weaken then dissipate by Mon. Elsewhere inside the
Gulf of California, moderate S to SW winds generally prevail
north of Ileana, and are strong SW across NW portions north of
30N. Seas across the area are 2-3 ft except 4 to 6 ft NW
portions.

A persistent broad and weak ridge extends southeastward into the
area waters tonight. The resultant pressure gradient is
producing gentle to moderate NW winds prevail across the
near and offshore waters of Baja California, and extend to Cabo
Corrientes and the Revillagigedo Islands. Seas across these area
waters are generally 3 to 5 ft except to 6 ft across the waters
NW of isla Guadalupe. Light and variable winds dominate the
waters from Manzanillo to the Tehuantepec region where seas are 4
to 5 ft in southerly swell east of 103W, with mixed NW and S
swell west of 103W. Widely scattered thunderstorms have shifted
off the coast and into the nearshore waters of Michoacan and
Colima.

For the forecast, Post-Tropical Cyclone Ileana will continue to
weaken as it moves northwestward and dissipates today. Fresh to
strong SW winds will continue over portions of the northern Gulf
of California through early Tue morning, where seas will build
to 5 to 6 ft. Elsewhere, broad high pressure will remain northwest
of the area and maintain gentle to moderate northerly winds
across the Baja offshore waters today before winds increase
slightly Mon night through Wed morning. Winds will pulse
to fresh during the afternoon and evenings off the Baja
California coast Mon through Fri. Expect seas of 3 to 6 ft to
persist through Tue morning. New northerly swell will move into
the regional waters Tue through Wed, bringing seas to 5 to 7 ft
before slowly subsiding Thu and Fri.

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

Winds have shifted offshore around 15 kt tonight across the
Papagayo region. Elsewhere Light and variable winds prevail
across the regional waters north of 10N. Seas there range 4 to 5
ft in south swell. S of 10N, 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.
Scattered thunderstorms continue within 150 nm of the coasts
from Guatemala to Costa Rica. Scattered to numerous strong
thunderstorms have developed recently across the waters of Panama
extending to 06N.

For the forecast, gentle to moderate southwest to west winds
will continue south of the monsoon trough through Tue, then
freshen modestly Wed and Fri. North of the trough, light to
gentle winds are expected through Thu. Moderate offshore gap
winds will continue across the Papagayo region and persist
through Tue night before shifting SE. Moderate seas in primarily
southwest swell will continue through Wed before increasing
Wed night through Fri.

...REMAINDER OF THE AREA...

A 1031 mb high continues across the NE Pacific along 145W,
extending a broad ridge southward into the region, dominating
the area north of the ITCZ and west of about 122W. The related
pressure gradient is producing generally moderate to fresh
northeast trades S of 23N and W of 123W per recent scatterometer
data. Fresh to locally strong winds are noted north of the ITCZ
to 20N and W of 135W where seas are 8 to 9 ft. Seas across the
rest of the area are 5 to 7 ft in mixed swell. Gentle to
moderate winds and seas 4 to 5 ft are noted N of 27N. Moderate
to fresh south to southeast 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 SW
through the week, 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 by Wed through Fri.
Moderate to fresh southwest to west 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