292
AXPZ20 KNHC 150921
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Fri Nov 15 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
0915 UTC.

...SPECIAL FEATURES...

Gulf of Tehuantepec Gale Warning: Minimal gale force winds are
ongoing in the Tehuantepec region as high pressure continues to
surge southward along the eastern slopes of the Sierra Madre
Mountains in Mexico behind a cold front moving across the Gulf of
Mexico. Seas with these are expected to peak to around 12 ft
early this morning, with the plume of seas exceeding 8 ft
reaching as far south as 10N today. An overnight scatterometer
pass caught the eastern edge of the gap winds where it indicates
winds of 20-30 kt there. Winds will lower to below gale force by
early this afternoon, with fresh to strong winds persisting
through Sat morning.

Eastern Pacific Swell Event: Large, long-period NW swell of 8 to
11 ft is impacting most of the region north of 10N west of 115W.
A reinforcing set of NW swell is propagating through the NW
waters, building seas to 12 to 14 ft NW of a line from 30N126W
to 25N140W. This swell set follows a cold front that extends
from near 30N117W to 25N129W. The reinforced NW swell will
continue to propagate across the waters N of 20N and W of 115W
today. Seas will subside north of 25N by Sat, but 12 to 14 ft
seas will persist from 15N to 20N west of 130W by Sat evening,
where the NW swell will mix with shorter-period NE waves
associated with the fresh to strong NE trade wind flow. Combined
seas in excess of 8 ft are expected mainly north of 05N and west
of 105W into early next week.

For more details, please read the latest NWS High Seas Forecast
issued by the National Hurricane Center at website
https//www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details.

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

The monsoon trough axis extends from 12N87W to 10N97W to 14N104W
to low pressure of 1011 near 12N109W to low pressure of 1011 mb
near 12N118W to low pressure of 1009 mb near 09N129W to 08N140W.
Scattered strong convection is within 30 nm of the trough between
110W-112W. Scattered moderate to isolated strong convection is
seen within 60 nm north of the trough between 87W-89W and between
118W-120W. Scattered moderate convection is within 120 nm north
of the trough between 137W-140W.

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

Please see the Special Features section for details on an
ongoing Gulf of Tehuantepec Gale Warning.

A broad area of fall/winter-type strong high pressure is
building over the eastern Pacific behind and across the southern
portion of a cold front approaching Baja California from the
west. This pattern is supporting fresh NW winds over the central
and southern parts Gulf of California this afternoon where seas
are in the 3 to 5 ft range. Light to gentle NW winds are over
the offshore waters of Baja California Sur south of Cabo Sab
Lazaro, while mostly fresh NW winds are north of that location.
Seas of 7 to 9 ft in NW swell are impacting the outer offshore
waters of the Baja California peninsula. Farther south, a gap
wind gale event is ongoing in the Gulf of Tehuantepec as
described in the Special Features section. Light to gentle winds
dominate the remainder of the Mexican offshore waters with seas
of 4 to 6 ft in mixed NW and SW swell.

For the forecast, a Gale Warning remains in effect until early
this afternoon for the Gulf of Tehuantepec. The gale winds are
producing rough seas. Elsewhere, large NW swell will continue to
move through the waters off Baja California through late Sat
while slowly subsiding. A cold front that extends from just W of
northern Baja California to beyond the offshore waters will begin
to weaken this afternoon and dissipate tonight. Expect fresh to
strong SW to W winds in the northern Gulf of California ahead of
the front this morning. Looking ahead, another round of
reinforcing NW swell will reach the waters off Cabo San Lazaro
today, and the Clarion Island Sat through Sun night. The swell
will gradually subside early next week.

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

Persistent SW flow in the eastern Pacific region will continue to
bring a fair amount of tropical moisture across southern Central
America maintaining the risk of locally heavy rain. The monsoon
trough is now propagating under the influence of Tropical Storm
Sara that is presently in the western Caribbean. Available
moisture is going to begin to decrease in Costa Rica and Panama
in the coming days. The highest accumulation totals is expected
to occur in the Pacific Sur region of Costa Rica and the NW
Pacific coast of Panama today. This information is provided by
the Weather Prediction Center`s International desk team. Please
refer to your national weather agency for details. Gentle to
moderate S to SW winds are offshore southern Central America,
except for slightly higher winds of fresh speeds that are
offshore El Salvador and northern Costa Rica. Gentle to moderate
winds are also noted elsewhere along with seas generally in the 3
to 5 ft range due to S to SW across the entire region.

For the forecast, gentle to moderate SW winds will increase to
moderate to locally fresh speeds across the coastal waters from
Panama to Nicaragua, including the Gulf of Panama through Sat,
supported by the cyclonic circulation associated to Tropical
Storm Sara that is located in the western Caribbean Sea. Farther
north, large northerly swell related to a gap wind event in the
Gulf of Tehuantepec will impact the outer offshore waters of
Guatemala and El Salvador through Sat. Elsewhere, gentle to
moderate winds and moderate seas in SW swell are expected.

...REMAINDER OF THE AREA...

Please refer to the Special Features sections for details about
large swell propagating through the eastern Pacific waters.

A cold front is moving across the NE forecast waters, and extends
from near 30N117W to 25N129W. Fresh to strong N to NE winds and
seas of 9 to 14 ft follow the front. The front is forecast to
weaken to a frontal trough, reaching from NW Mexico to 20N120W to
19N130W and to 19N130W and to 17N140W by early this evening.
Building high pressure in the wake of the front is supporting a
broad area of fresh to strong trades from 15N to 26N W OF 135W.
Seas are 8 to 11 ft in NW swell within these winds. Multiple low
pressure centers remain along the monsoon trough. See above under
ITCZ/Monsoon Trough section for low pressure positions.
Increasing scattered to numerous showers and thunderstorms are
near these systems. An area of fresh to strong winds is noted on
the W semicircle of the westernmost low pressure. It will
continue to move westward over the next couple of days. The
eastern most low is forecast to acquire fresh to strong winds in
its SE quadrant starting tonight.

For the forecast, the aforementioned cold front will dissipate
tonight as a frontal trough. Long-period NW swell behind the
front will reinforce the existing field of swell across the
waters ultimately extending as far as south of 05N and west of
105W through Sun. Wave heights to 14 ft can be expected north of
20N through at least Fri night. Fresh to strong trade winds will
also cover the basin N of 10N and west of 110W as a broad and
strong area of high pressure builds in the wake of the front.

$$
Aguirre