134
AXPZ20 KNHC 301539
TWDEP
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Tue Dec 30 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 1200 UTC surface analysis and satellite imagery through
1500 UTC.
...SPECIAL FEATURES...
Gulf of Tehuantepec Storm Warning: Gale-force northerly winds
are blowing across the Gulf of Tehuantepec and downwind to about
13N as high pressure builds southward the eastern slopes of the
Sierra Madre Mountains in Mexico. Winds will increase to storm
force this afternoon and evening, with seas building to 12 to 18
ft. Large seas generated from these gap winds will spread well
away from the Tehuantepec area, with seas 8 ft or greater
reaching as far west as 105W by this evening into tonight. Marine
interests transiting across or near the Gulf of Tehuantepec
through Wed should take the necessary action to avoid these
hazardous marine conditions. Although storm conditions will end
by Wed morning, gales will prevail through Wed night. Winds and
seas will gradually diminish Thu and Thu night.
Of note: The monthly distribution of Tehuantepec events shows
that the largest number of gale force events occurs in December.
Storm-force events occur most often in January.
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 extends from 10N85W to 06N92W. The ITCZ
stretches from 06N92W to 10N109W, then continues from 09N131W to
beyond 06N140W. No significant convection is associated these
features at this time.
...OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
A Storm Warning is in effect for the Gulf of Tehuantepec. Please
refer to the Special Features section for details.
A 1025 mb high pressure is located well north of the area near
41N130W. A ridge axis extends from the high southward to W of the
waters offshore Baja California, supporting gentle to moderate
north to northeast winds with moderate seas, with the exception
of moderate to locally fresh NE winds in the Bay of Sebastian
Vizcaino. Fresh to strong NW to N winds are evident across the
Gulf of California due to the presence of a strong 1043 mb high
pressure over the Great Basin. Seas are 6 to 8 ft within these
wind speeds. Fresh to strong N winds are also in the vicinity of
San Jose del Cabo. Elsewhere, gentle to moderate winds and
moderate seas in NW swell are noted.
For the forecast, aside from the storm conditions over the Gulf
of Tehuantepec, strong high pressure over the Great Basin will
support fresh to strong northwest winds and moderate to rough
seas across most of the Gulf of California through tonight.
Elsewhere, moderate or weaker winds and slight to moderate seas
are expected.
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA,
AND WITHIN 750 NM OF ECUADOR...
Strong high pressure building north of the region is supporting
fresh to strong northeast to east winds in the Gulf of Papagayo
and downwind to near 88W. Seas of 5 to 7 ft are within these
winds. Elsewhere, moderate or weaker winds and slight to moderate
seas prevail.
For the forecast, the aforementioned high pressure will continue
to support fresh to strong NE to E winds in the Gulf of Papagayo
with moderate to rough seas through the forecast period. The
forecast calls for winds of 20 to 30 kt, mainly at night, with
seas building up to 10 ft through Thu night. Gentle to locally
moderate northerly winds are expected in the Gulf of Panama
through Fri. Seas generated by strong winds in the Tehuantepec
region will propagate across the offshore forecast waters of
Guatemala and El Salvador today through Wed night. Light to
gentle winds and slight to moderate seas are expected elsewhere
through this work-week.
...REMAINDER OF THE AREA...
A 1006 mb surface low pressure is centered near 21N127W. A
surface trough extends from the low center to 16N124W to 10N128W.
An area of numerous moderate to isolated strong convection is
noted E of the trough axis from 12N to 21N between 110W and 123W.
This is associated with a broad upper-level cyclone over the
same area. Recent satellite derived wind data indicate that winds
related to this low have diminished below gale force, and the
Gale Warning is allowed to expired. However, a large area of
fresh to strong winds remains associated with this system, and
continues to dominate roughly the waters N of 16N W of 118W. Seas
of 8 to 12 ft, primarily in NE swell, are noted from 14N to 27N
W of 120W. As the low pressure moves northward over the next 24
to 48 hours winds and seas will gradually diminish. Elsewhere,
gentle to moderate winds and 5 to 7 ft seas primarily in NW swell
are evident elsewhere.
For the forecast, outside of the complex low pressure system and
the swell event, a cold front is forecast to reach near 30N140W
Wed night and move westward across the waters north of 25N into
Thu. A reinforcing front will also reach the same area later on
Thu, merging with the main front by Thu evening. At that time,
the front will extend from 30N134W to 24N140W. Fresh to strong
winds are expected on either side of the front. A new swell event
will follow the front bringing rough to very roughly seas.
$$
Konarik
