000
AXPZ20 KNHC 281006
TWDEP
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Sun Dec 28 2025
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
0945 UTC.
...SPECIAL FEATURES...
Gulf of Tehuantepec Gale Warning: Strong high pressure over
the southern United States and across eastern Mexico in the
wake of an upcoming Gulf of America cold front will result
in a tight pressure gradient that is expected induce gale-force
winds north winds into the Gulf of Tehuantepec region beginning Mon
night. These winds may peak to 45 kt going into the middle part
of the upcoming week. Brief gusts to storm force cannot be ruled
out Tue night. Seas with these winds are expected to rapidly
build to the range of 11 to 18 ft (3.5 to 5.5 m) with these
winds. Mariners transiting through the Gulf of Tehuantepec
during this upcoming gap wind gale event are urged to take the
necessary action to avoid the hazardous marine conditions that
will be impacting these waters. Conditions in the Tehuantepec
region are forecast to begin to improve early on Thu.
Developing Low Pressure: A surface trough analyzed from near
20N124W to 15N127W and to near 11N127W in conjunction with a
rather vigorous and broad upper trough that is digging southward
is producing a large area of moderate to heavy rain with embedded
scattered to numerous showers and thunderstorms generally from
15N to 27N between 117W and 125W. Scattered moderate convection
is noted from 12N to 15N between 116W and 125W, and also from 12N
to 20N between 125W and 134W. An overnight scatterometer
satellite data pass indicated that strong to gale-force winds
are occurring with the strongest convection. Global models
suggest that low pressure will develop in association with this
trough across the waters south of about 22N between 120W and 128W
today into early next week. The interaction between this feature
and strong high pressure building into the region is expected to
result in a rather broad zone of increasing winds reaching to
strong speeds roughly from 16N to 26.5N and west of the
Revillagigedo Islands, accompanied by numerous areas of moderate
to heavy rain along with embedded scattered showers and isolated
thunderstorms. There is a possibility that these winds may attain
gale-force speeds, especially in the showers and thunderstorms.
Rough to very rough seas will spread over much of the basin north
of 10N and west of 115W. Seas may reach up to 15 ft with the
strongest winds. Conditions are forecast to improve by the middle
of the week.
Significant Swell over the Central Waters: Large northwest swell
continues to generate mostly rough seas north of about 18N and west
of about 114W, with seas peaking to 13 ft (4 m) from 20N to 24N
between 121W and 123W. Wave period with these seas is of 12-14 sec.
Rough seas extend southward to near 10N and east-northeast to the
offshore waters of Baja California, including Sebastian Vizcaino
Bay. The swell will slowly subside through this evening south of
28N. Rough seas of 8 to 12 ft are likely to prevail into Mon over
the waters just west of the Baja California Sur offshore zones,
roughly from 15N to 25N.
Please read the latest High Seas Forecast issued by the National
Hurricane Center at website:
https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more information.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough axis extends from northern Colombia to 08N79W
to 08N91W to 08N100W, where latest scatterometer satellite data
indicates that it transitions to the ITCZ to 09N115W to 10N124W
to 08N133W and to beyond the area at 07N140W. Scattered moderate
convection is seen within 180 nm north of the trough between
116W and 120W.
...OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
Please refer to the Special Features section for details on
a gale warning that is in effect for the Gulf of Tehuantepec.
Strong high pressure of 1033 mb is located well north of the
area near 41N132W. A ridge axis extends from the high southward
to near 20N and west of the Revillagigedo Islands. Its related
gradient is allowing for fresh north to northeast winds to exist
across the offshore waters of Baja California. A decaying
northwest swell is providing for seas of 8 to 10 ft offshore Baja
California, except for lower seas of 6 to 9 ft south of Cabo San
Lazaro. Moderate to locally fresh northwest winds and slight to
moderate seas are found in the Gulf of California. while moderate
north winds are in the Gulf of Tehuantepec region. Seas over
these waters are 4 to 6 ft. Elsewhere, moderate or weaker winds
and slight to moderate seas prevail.
For the forecast, northwest swell propagating through the
offshore waters of the Baja California peninsula will gradually
subside through early Mon. Fresh to locally strong northwest
winds are likely to develop in the Gulf of California today and
continue into Tue night as high pressure strengthens across the
region. Gentle to moderate north winds in the Gulf of Tehuantepec
region will become fresh north winds early on Mon. Looking
ahead, a strong cold front will move across the Gulf of America
Mon into Tue. High pressure building in behind the front will
support the next gap wind event in the Gulf of Tehuantepec as
describe above under the Special Features section.
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA,
AND WITHIN 750 NM OF ECUADOR...
High pressure centered over the eastern Gulf of America has an
associated broad ridge that stretches southwestward toward
Central America. The gradient between the ridge and relatively
lower pressure to its south is allowing for fresh to strong
northeast to east winds to exits in the Gulf of Papagayo region
along with seas of 4 to 6 ft. Weak low pressure off Colombia is
producing isolated showers and thunderstorms south of the Gulf
of Panama from 05N to 07.5N between the coast of Colombia and
80W. Elsewhere, moderate or weaker winds and moderate seas
prevail.
For the forecast, the aforementioned high pressure will
continue to support pulsing fresh to strong easterly trade winds
in the Gulf of Papagayo through the forecast period. Gentle to
moderate northerly winds are expected in the Gulf of Panama
through the period, pulsing to fresh at night at times. Gentle or
lighter winds and slight to moderate seas are expected elsewhere
through the period.
...REMAINDER OF THE AREA...
Please read the Special Features section for details on significant
swell over the waters central portion of the area, and for conditions
that will soon be associated with low pressure impacting most of
the northern waters and portions of the central waters.
Broad ridging associated to strong high pressure that is
centered well north of the area reaches southward into the area
to near 20N. A trough is analyzed from 20N124W to 15N127W and to
near 11N 127W. The gradient between the ridge and relatively
lower pressure in the tropics is allowing for moderate to fresh
trade winds north of about 10N and west of 120W. Seas outside of
the Special Feature significant swell area are 8 to 11 ft.
Elsewhere, moderate or weaker winds and moderate seas are
prevalent.
For the forecast, the slowly decaying northwest swell is
forecast to maintain that trend through early Mon as high
pressure builds into the regional waters. The aforementioned
trough will serve as the seedling for the development of a
broad low today, perhaps near 18N125W. The tight pressure
gradient between the subtropical ridge and the low pressure will
sustain a large area of strong to near gale-force winds and
rough to very rough seas, across most of the forecast waters
north of about 15N and west of 117W into the early part of
the week. Winds may reach gales at times, more likely in
scattered showers and thunderstorm, but with some possibility
of winds become sustained at gale-force speeds in the tight
gradient north of the low. Conditions are forecast to improve
by the middle of the week. Looking ahead, a cold front will move
across the NW waters late next week, followed by fresh to strong
NW winds and rough to very rough seas.
$$
Aguirre