000
AXPZ20 KNHC 120958
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Thu Dec 12 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.

...SPECIAL FEATURES...

Tehuantepec Storm Warning: The most significant gap wind event
thus far of the season continues tonight across the Gulf of 
Tehuantepec, and will continue through Fri morning. Strong high 
pressure across the NW Gulf of Mexico is building southward 
across the region, behind a cold front stretching across western 
Cuba to northern Honduras. This pattern is supporting storm-
force N winds from the Tehuantepec coast to near 14N, with 
strong to gale-force winds then extending 300 nm offshore of the
coast. Evening satellite altimeter data measured high seas of 14
to 18 ft downwind of Tehuantepec, and seas are likely peaking at
18 to 21 ft tonight. Winds are expected to diminish below storm-
force within the next few hours. Strong gales will then continue
Thu and very slowly diminish below gale-force near sunrise on 
Fri. Strong to near- gale force strength winds are then expected 
to continue Fri through Mon morning as strong high pressure 
persists across the Gulf of Mexico and the NW Caribbean. Large 
swell of 8 ft and greater generated from this significant event 
will spread as far south as 06N by Thu evening, extending between
the Papagayo region and 105W. Significant winds and seas 
occurring this weekend across Tehuantepec are only expected to 
extend to around 240 nm offshore.

Please read the latest High Seas and Offshore Waters Forecasts 
issued by the National Hurricane Center at website: 
https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and 
www.nhc.noaa.gov/marine/offshores_eastpac.php for more 
information.

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

The monsoon trough axis extends from 09N76W to 10N85W to 06.5N92W
to 07N102W. The ITCZ then continues from 07N102W to 09N118W to 
beyond 06.5N140W. Scattered moderate isolated strong convection 
is noted from 05N to 07.5N E of 80W and from 06N to 10N between 
96W and 125W.

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

Please refer to the Special Features section for information on
the Gulf of Tehuantepec Storm Warning.

Strong high pressure over the Four Corners region of the western
U.S. extending southward into the Gulf of California, to the 
west of troughing along the Sierra Madre Occidentals of northwest
Mexico, has weakened and begun to shift eastward tonight. Strong
winds across the Gulf of California and extending to offshore of
Cabo Corrientes this past afternoon are steadily weakening to 
moderate to locally fresh tonight, with seas subsiding to 4 to 7 
ft. Elsewhere a broad high pressure ridge extends southeastward 
into Baja California and southwestern Mexico. This pattern is 
producing gentle to moderate NW to N winds across the Baja 
offshore waters, where seas are 5 to 7 ft in NW swell, except to 
8 ft NW of Isla Guadalupe. Farther south, weak ridging prevails 
off the coast of southwestern Mexico, leading to light to gentle 
winds. Seas off the coast of southwestern Mexico range from 4 to 
6 ft in NW to W swell. 

For the forecast, winds and seas will slowly diminish across the
Tehuantepec region this afternoon through Thu night with gales 
forecast to end near sunrise on Fri. Winds are expected to remain
strong to near gale-force strength Fri through Mon morning there
as a strong high pressure ridge persists across the Gulf of 
Mexico and the NW Caribbean. Elsewhere, moderate to locally 
fresh NW winds and rough seas will build across the waters north 
of Punta Eugenia Thu night into Fri, as a weakening cold front 
moves into the Baja Norte waters. High pressure will build 
modestly across the area waters Sat afternoon through Mon behind
this dying front to bring a return to moderate to locally fresh 
NW to N winds across all waters W of Manzanillo. 

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

A tightening pressure gradient across Central America is
developing as strong high pressure over the Gulf of Mexico is
building southward into the region behind a cold front across 
the northwestern Caribbean that stretches from western Cuba to
northern Honduras. Fresh to strong NE winds are across the Gulf 
of Papagayo region, where seas are 6 to 7 ft. Elsewhere N of 10N
winds are light to gentle with seas generally 4 to 6 ft. S of 10N
light to moderate S to SW winds and seas of 4 to 5 ft are noted 
south of the monsoon trough, with moderate N winds occurring
across the western Gulf of Panama. 

For the forecast, fresh to strong NE gap winds are expected 
across the Gulf of Papagayo region through Fri morning as strong 
high pressure persists across the NW Caribbean behind a cold 
front. Winds across the Papagayo region will then pulse to strong
at night through Sun morning. Strong northerly winds and very 
rough seas occurring along the eastern edge of a strong 
Tehuantepec gale-force wind event will impact the offshore waters
of southwestern Guatemala through Fri, with associated NW swell 
spreading to offshore of Papagayo by Thu afternoon. Winds 
offshore of Guatemala will diminish Thu night with seas slowly 
subsiding through Fri afternoon. Moderate N winds across the 
western Gulf of Panama will pulse to fresh at night through this 
weekend. Otherwise, gentle to moderate S to SW winds and moderate
seas will prevail south of the monsoon trough, with gentle winds
and slight seas occurring north of the trough, away from the gap
winds. 

...REMAINDER OF THE AREA...

A 1027 mb high is centered northwest of the area near 38N140W, 
and extends a broad ridge south and southeastward to the north 
of the ITCZ. Moderate to fresh trades are occurring south of 25N
and west of 120W, with locally strong NE to E winds occurring 
between 08N and 20W west of 136W, where seas are 10 to 13 ft in
NW swell. North of 25N, gentle to locally moderate anticyclonic 
winds are noted, ahead of an approaching cold front along 32N 
Fresh NW swell is combining with residual seas north of the ITCZ,
to produce a broad swath of seas of 8 to 11 ft north of 05N and 
west of 120W. South of the ITCZ, moderate to locally fresh SE 
winds and seas of 5 to 8 ft prevail.

For the forecast, the NW swell will propagate southeastward over
the next several days, with this swell combining with trade wind
swell along and north of the ITCZ. This will maintain seas of 8
ft and higher north of 06N and west of 118W tonight through Fri.
Peak seas around 13 ft are expected in the far western waters 
between 10N and 20N west of 135W in the zone of strongest trade
winds. These fresh to strong trades winds will continue from 
north of the ITCZ to 20N, west of 120W. Farther east, moderate to
locally fresh trade winds will continue north of the ITCZ to
around 15N between 105W and 120W. Moderate NW swell moving
through the regional waters will merge with NE swell generated 
downwind of the Gulf of Tehuantepec to produce rough seas of 8 to
12 ft across these waters through Sun before conditions improve.
An E to W ridge will move into the area waters along about 27N
over the weekend to maintain fresh trade winds from 20N to the 
ITCZ into early next week.

$$
Stripling