Eastern Pacific Tropical Weather Discussion

375
AXPZ20 KNHC 121452
TWDEP 
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Thu Nov 12 2026
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
1430 UTC.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough extends from 1008 mb low pressure along the NW
coast of Colombia in the Caribbean Sea at 11N75W to across the
border of Costa Rica and Nicaragua to the Gulf of Papagayo at
11N86W to 06N100W to 05N120W to 09N132W to 07N140W. Scattered 
moderate to isolated strong convection is observed from 02.5N to
08N between 77W and 80W, from 01.5N to 05.5N between 81W and
85.5W, from 02S to 07.5N between 103W and 126.5W, and from 06N to
15.5N between 126.5W and 140W.
...OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
Fresh to strong northern winds are in the Gulf of Tehuantepec
supported by the pressure gradient between a high pressure 
system over the southern United States and lower pressures with
the monsoon trough SE of the area. Seas in this waters are 4-7 
ft. Meanwhile, a weak pressure gradient is present in the 
remainder of the Mexican offshore waters with mainly moderate or
weaker winds. Decaying NW swell is producing seas of 5-8 ft 
across much of the area, except for slight seas in the Gulf of 
California.
For the forecast, fresh northerly winds and rough seas around 8 
ft will pulse to strong at night across the Gulf of Tehuantepec 
through Fri night with locally rough seas. The next Tehuantepec 
gap wind event is forecast to begin early next week and continue 
through much of the next week. Winds may reach gale-force 
starting late Mon night. Meanwhile, a cold front will move 
across the offshore waters of Baja California Fri, bringing fresh
winds and a new batch of rough seas approaching 12 ft. Fresh to 
locally strong winds may also briefly impact the northern Gulf of
California Fri. Then, a larger NW swell arriving Sat will 
produce high seas to 20 ft. Rough seas will reach all the way to 
past 100W by early next week, while additional and reinforcing NW
swell sets continue to arrive. 
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, 
AND WITHIN 750 NM OF ECUADOR...
A broad subtropical ridge centered north of the area sustains
moderate to locally fresh easterly winds and seas of 2-4 ft in
the Gulf of Papagayo region. Elsewhere, moderate or weaker winds
and moderate seas are prevalent, except locally rough seas SW of
the Galapagos Islands in merging long period SW and NW swells.
For the forecast, moderate to fresh NE-E winds in the Gulf of
Papagayo will diminish later today. Moderate to fresh winds may 
return to the Papagayo region by the end of the weekend into 
early next week, possibly reaching strong speeds by late Mon 
night. Otherwise, moderate or weaker winds and moderate seas in 
merging SW and NW swell will prevail, except locally rough SSW of
the Galapagos Islands through Fri night.
...REMAINDER OF THE AREA...
A cold front continues to move quickly southeastward across the NW
waters, extending from 30N128.5W to 23N140W. The tight pressure 
gradient between high pressure centered well WNW of the area, 
and the aforementioned front sustains fresh to strong NW-N winds 
behind the front, along with seas of 8-18 ft, with the highest 
seas occurring near 30N137W. Old and decaying NW swell supports
seas of 7-9 ft out ahead of the front. In the western trade 
waters, a surface trough analyzed just W of 140W extending to the
monsoon trough E of 140W is producing a large area of showers 
and isolated thunderstorms as described above. Moderate to fresh 
easterly trade winds and rough seas are found from 12N to 19N and
west of 129W. Merging SW and NW swells supports combined seas of
7-10 ft across much of the waters S of 12N between 97W and 127W.
In the southern waters, moderate to fresh SE winds and rough 
seas are found south of 02N. Elsewhere, winds are moderate or 
lighter and a decaying NW swell is found across much of the 
remainder of the basin, supporting seas of 6-8 ft. Mainly
moderate or weaker winds and moderate seas are found across the 
remainder of the waters, except locally fresh S of the Equator 
and W of 100W.
For the forecast, the aforementioned cold front will move across
the northern waters today into early Fri, bringing with it fresh
to strong winds on either side of the front, and very large seas
in NW swell north of 20N through Fri. Another cold front will 
sweep across the area Fri into the weekend, bringing even larger 
reinforcing NW swell, possibly reaching 24 ft along 30N. This set
of swell with seas of 8 ft or greater will cover the waters N of
05N and W of 110W by late Sat night, then covering all of the 
waters W of 105W. Yet another set of large swell will arrive Sun,
with seas of 8 ft or greater across the entire waters W of 105W 
by late Sun night. Meanwhile, the mixed swell over the equatorial
waters will diminish by the weekend. Looking ahead, another cold
front may move into the NW waters by the end of the weekend into
early next week bringing a large area of fresh to strong winds 
behind it as high pressure builds in.