088 
AXPZ20 KNHC 301603
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Sat Dec 30 2023

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 1200 UTC surface analysis and satellite imagery through
1530 UTC.

...SPECIAL FEATURES...

Gulf of Tehuantepec Gale Warning: Strong high pressure centered
over NE Mexico is forcing gale force winds across the Gulf of 
Tehuantepec. The gale force northerly gap winds are expected to 
persist through tonight, diminishing early Sun morning. Seas of
12 to 13 ft will persist during that time. Seas will then 
subside by Sun night across the region. Strong winds will also 
briefly subside by early Mon morning.

Large Swell Event Across Eastern Pacific: A cold front stretches
across the Eastern Pacific from 30N120W to 25N123W to 22N131W,
dissipating to 21N135W. Large NW swell, with seas of 12 to 19 ft,
is occurring north of 05N and west of 115W, with highest seas
north of 20N between 120W and 135W. The 8 ft seas extend
southward beyond the Equator, and as far east as Cabo Corrientes,
Mexico. The front will dissipate tonight over the Baja 
California offshore waters. However, the reinforcing swell will 
continue to spread south and east across the waters through early
Mon. Seas will subside below 16 ft tonight and below 12 ft by 
Sun night.

Please refer to the High Seas Forecast issued by the National 
Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml
for details on both special features.

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

The monsoon trough extends from the coast of Costa Rica near
09N84W to 04N96W. The ITCZ continues from 04N96W to 07N118W to 
beyond 06N140W. Scattered moderate convection is noted from 04N 
to 09N between 104W and 118W, and from 05N to 08N between 131W
and 140W. 

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

See the Special Features Section above for details on a Gale 
Warning for the Gulf of Tehuantepec.

A cold front extends from 30N120W to 25N123W to 22N131W. To the
west of Baja California, mostly moderate NW winds prevail. Seas
west of Baja are 8 to 17 ft in large NW swell. In the Gulf of
California, gentle to moderate winds with 1-3 ft seas are 
present. Gentle to moderate winds are elsewhere offshore Mexico, 
except gale force in the Gulf of Tehuantepec. Seas west of 
Jalisco are 10 to 12 ft in NW swell. Seas off Guerrero are 5 to 
10 ft in NW swell.

For the forecast, the cold front extending from 30N120W to
25N123W to 22N131W will dissipate tonight as it moves eastward 
through the Baja California offshore waters. Very large NW swell
impacting the Baja California offshore waters will bring seas of
12 to 17 ft through early Sun. Seas of 8 to 11 ft are expanding 
across most of the southwest and southern Mexico offshore waters 
through the weekend. A second cold front will move through the 
Baja California offshore waters late Sun night through Mon,
keeping seas in the 8 to 10 ft range offshore early next week
through Tue.

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

Fresh NE to E gap winds are occurring in the Gulf of Papagayo
region. Elsewhere, quiescent marine conditions dominate the 
waters with gentle to moderate winds and seas of 4-6 ft in mixed 
swell.

For the forecast, a building ridge north of the area will 
support fresh to strong NE gap winds over the Gulf of Papagayo 
region tonight through Tue night. Seas will build to 8 ft Sun 
through Mon night. Meanwhile, gale-force gap winds in the Gulf 
of Tehuantepec will cause NW swell with seas 7 to 9 ft over the 
Guatemala and El Salvador offshore waters this afternoon into 
Sun night. Fresh N winds will pulse at night in the Gulf of 
Panama from Sun night through Tue night. Otherwise, a weak 
pressure gradient will result in moderate or lighter winds across
the rest of the area through early next week. 

...REMAINDER OF THE AREA...

See the Special Features Section above for details on the very 
large NW swell across most of the forecast waters. 

The weak pressure gradient between a 1025 mb high at 28N138W and
the ITCZ is yielding moderate to fresh NE trades from the ITCZ 
to 22N and west of 120W. South of the ITCZ and monsoon trough, 
winds are moderate or less. Seas of 8 to 14 ft prevail across 
most of the area west of 104W and SE of a line from 27N120W to 
10N140W. To the NW of that line, seas are 14 to 19 ft. East of 
105W, seas are 5 to 7 ft.

For the forecast, see the Special Features section above for 
details on the very large swell over much of our forecast 
waters. The current NW swell will subside to the 8 to 12 ft range
across most of the area by Sun afternoon. Elsewhere, the cold
front extending from 30N120W to 25N123W to 22N131W will 
dissipate tonight as it moves eastward. High pressure is 
expected to build across the northwest waters later in the 
weekend. This will enhance the NE trades between the ITCZ and 
20N, and to the west of 127W from Sun through most of the week, 
bringing fresh to strong winds and 8 to 12 ft seas to the area.
Another cold front will cross 30N140W tonight, reach from 30N126W
to 26.5N132W Sun evening, then weaken by Mon evening as it
approaches Baja California. Fresh to strong winds are expected
north of 27N with this front.

$$
Hagen