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Eastern North Pacific Tropical Weather Discussion


538 
AXPZ20 KNHC 210249
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Fri Aug 21 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 0000 UTC surface analysis and satellite imagery through
0230 UTC.

...SPECIAL FEATURE...
An area of low pressure has developed in the tropical wave
environment, analyzed along 114W. The low is centered near 
07.5N114W, with minimum pressure of 1008 mb. A large area of 
disorganized showers and thunderstorms prevails from 02N to 16N
between 111W and 120W. Environmental conditions appear favorable
for gradual development, and a tropical depression could form 
this weekend or early next week while the system moves west- 
northwestward or northwestward at 5 to 10 kt. THis system has a
medium chance for tropical formation within 48 hrs and 7 days.

Please refer to the latest NHC Tropical Weather Outlook at 
website: https://www.nhc.noaa.gov/text/MIATWOEP.shtml for more 
details on these systems.

...TROPICAL WAVES...

The axis of a tropical wave is moving over eastern portions of 
the Tropical Pacific basin along 85W, N of 03N, moving westward 
at 15 to 20 kt. Scattered moderate to strong convection is noted 
S of 09N and E of 89W.

The axis of a tropical wave is near 100W, N of 05N, moving 
westward at 10 to 15 kt. Scattered moderate to strong convection
stretches from 05N to 15N between 94W and 110W, as the wave 
interacts with a middle level trough extending off the SW coast 
of Mexico. Environmental conditions appear favorable for gradual 
development, and a tropical depression is likely to form this 
weekend or early next week while the system moves west-northwestward 
or northwestward, remaining well offshore of Mexico. This system
has a high chance for tropical formation within the next 7 days.

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

The monsoon trough extends from 10N85W to 08N137W. Aside from the
convection related to the tropical waves described above,
scattered moderate convection is noted within 200 nm on either
side of the trough.

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

Please refer to the Tropical Waves section above for information
on a tropical wave that has a potential for tropical development
offshore Mexico this upcoming weekend, and for related
convection. 

A modest pressure gradient continues across the Gulf of
Tehuantepec area, where the northern portion of a tropical wave 
has moved W of the Gulf, and is producing strong N to NE gap 
winds in the Gulf and downstream to near 13N98W. Seas are 5 to 7
ft across that area. Across the remainder of the offshore waters 
of Mexico, typical ridging has been disrupted by a low level 
trough offshore of Punta Eugenia, along about 118W, resulting in 
a weak pressure gradient across the region. Latest scatterometer
data showed that this current pattern is producing light to 
gentle NW to N winds, except moderate near Cabo Corrientes. Seas 
are 4 to 5 ft across the waters away from the Gulf of 
Tehuantepec. Gentle southerly winds prevail across the far 
northern Gulf of California, and become gentle NW to N across the
remainder of the Gulf. Seas there are 1 to 3 ft. An upper level 
trough extending offshore of SW Mexico continues to support 
clusters of strong thunderstorms along the coasts and nearshore 
waters of Guerrero and Michoacan, and continue to shift westward,
ahead of an approaching tropical wave.

For the forecast, fresh northerly gap winds will continue to 
pulse to strong winds over the Gulf of Tehuantepec during the 
overnight into the early morning hours through the next several 
days, with seas occasionally building to rough. High pressure 
will begin to build back modestly across the Baja offshore waters
Fri afternoon through Sat night to produce a more typical 
moderate to fresh NW wind flow there. Southerly wind flow will 
return to the Gulf of California Sat night and become fresh to
locally strong Sun. Winds and seas are expected to build across 
the outer offshore waters of southwestern Mexico tonight into 
early next week in association with a developing area of low 
pressure moving westward and just outside of the offshore 
waters.

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

Refer to the Tropical Waves section above for details on any
convection.

Recent satellite scatterometer data shows fresh to strong NE to E 
gap extending across the Papagayo region to near 90W, where seas
are 5 to 7 ft. Fresh easterly winds then continue westward and 
downstream, and S of 12.5N, across the outer offshore waters of 
El Salvador and Guatemala, where seas are 6 to 7 ft. Mainly 
moderate or weaker winds are found elsewhere, with fresh winds near
the border of Peru and Ecuador close to the entrance to the Gulf
of Guayaquil. Seas are 4 to 6 ft across the remainder of the 
waters north of 04N, and 6 to 8 ft south of 04N. Clusters of 
strong thunderstorms are over the waters south of Panama and 
Costa Rica, due to the passing tropical wave there, described 
above.

For the forecast, high pressure will persist over the eastern
Gulf of America and northwestern Caribbean into early next week, 
leading to fresh NE to E gap winds pulsing to strong winds over 
the Papagayo region each evening and night. Moderate to fresh 
winds extending well downwind of Papagayo will impact the outer 
waters offshore of El Salvador and Guatemala through at least 
early next week. South of the monsoon trough, winds will 
gradually diminish and remain light to gentle through the
weekend. Mainly moderate seas will prevail away from the Gulf of
Papagayo area through the next several days. Southeasterly swell
producing rough seas across the southern waters will subside
this evening through Fri.

...REMAINDER OF THE AREA...

Please see the Special Features section and the Tropical Waves 
section above for information on systems that have the potential
for tropical cyclone formation, and any associated convection 
currently present leading to higher winds and seas.

High pressure across the NE Pacific extends a ridge south- 
southeastward into the regional waters to offshore of Baja Surf.
Fresh easterly winds and seas to 7 ft are noted in the periphery
of Tropical Depression Two-C in the Central Pacific basin are 
impacting the waters between 10N to 20N and W of 135W. Elsewhere, 
moderate to fresh trades are found from 10N to 22N between 124W 
and 140W , where seas are 5 to 7 ft. Moderate to fresh winds are
found south of 06N to the east of 118W and south of 04N to the 
west of 120W. Rough seas over the southern waters are gradually 
subsiding, and now cover the waters south of 02.5N E of 120W.

For the forecast, regardless of tropical development, the 
features described above will bring increasing winds and seas to
area waters south of 25N, as they move south of the current 
ridge in place. Away from these features, little change is 
expected in marine weather through the next several days, except 
for the rough seas over the southern waters, which are forecast 
to fully subside by the start of the weekend.

$$
ERA