168
AXPZ20 KNHC 152203
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Sat Aug 15 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 1800 UTC surface analysis and satellite imagery through
2145 UTC.

...TROPICAL WAVES...

The axis of a tropical wave is along 86W north of 03N to inland
central Nicaragua and eastern Honduras, It is moving westward at
about 15 kt. Nearby convection is discussed in the ITCZ/monsoon
trough section below.

The axis of a tropical wave is near 105W south of 17N. It is
moving westward at 10 to 15 kt. Numerous moderate to strong
convection is seen from 07N to 13N between the wave and 110W.

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

The monsoon trough extends from 1007 mb low pressure over
northern Colombia at 10N75W westward to along the coast of
central Panama, through southern Costa Rica to 10N84W to 07N92W
to 07N105W, where it transitions to the ITCZ to 04N117W to
07N124W and to 12N130W. Numerous moderate to strong convection
is from 04N to 09N between 80W-86W, and from 05N to 08N between
86W-90W. Scattered moderate to isolated strong convection is
within 60 nm of the trough between 86W-92W, and from 10N to 14N
between 125W-131W.

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

Fresh to near gale north gap winds are over the Gulf of
Tehuantepec as noted in a satellite ASCAT scatterometer pass
from earlier today. Moderate to locally fresh northwest winds
are near the Pacific coast of Baja California. Elsewhere, winds
are moderate or weaker. Seas are 5 to 7 ft over the Gulf of
Tehuantepec, 4 to 6 ft over the remaining Pacific waters, and 1
to 3 ft over the Gulf of California. No significant deep
convection is occurring over the Mexican offshore zones.

For the forecast, the pressure gradient between high pressure
over the Gulf of America and relatively lower pressure south of
Mexico will continue to induce pulses of fresh to strong north
winds well into the upcoming week over the Gulf of Tehuantepec
through the period. Winds may again reach near gale force
through Tue. Moderate to fresh northwest winds are forecast off
of the Baja California peninsula through Tue, with winds reaching
strong speeds near and north of Punta Eugenia east of 117W.
Elsewhere, winds and seas should remain rather calm until at
least mid next week. Looking ahead, an area of low pressure could
form several hundred nautical miles south of the coast of
southern Mexico near the middle portion of next week. Some
gradual development of this system is possible, while the system
moves westward or west- northwestward well south of Mexico.

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

Fresh to strong northeast to east gap winds are over the
Gulf of Papagayo region. Seas there are 6 to 8 ft. Elsewhere,
winds are moderate or weaker across forecast waters, except
locally fresh near the entrance to the Gulf of Guayaquil. Seas
are 5 to ft in long-period southwest over the remainder of
forecast waters. Numerous moderate to strong convection is
over the waters off Panama and Costa Rica.

For the forecast, the pressure gradient between high pressure
over the western Caribbean and relatively lower pressure over
Central America will lead to fresh to strong northeast to east
gap winds over the Gulf of Papagayo region through Sun night
before weakening early next week with winds diminishing to
moderate to fresh there. Moderate to fresh southerly winds will
pulse south of the monsoon trough through Mon. Large southerly
swell will impact the waters mainly from Ecuador to the Galapagos
Islands through the next several days, largest expected by
around the middle portion of the upcoming week.

...REMAINDER OF THE AREA...

As of 21 UTC, the remnant low of former Tropical Depression
Hernan is centered near near 15.8N 135.9W, or about 1530 nm west
of the southern tip of Baja California and with a pressure of
1009 mb. It is moving westward at 10 kt. Northeast to east winds
of 20 to 25 kt are within 420 nm of the low in the northern
semicircle of the low, where a tight pressure gradient exists
between it and high pressure over the northern waters. A
satellite Ascat altimeter pass from 1829 UTC clearly revealed
these winds. Seas are 8 to 10 ft with these winds. Moderate to
fresh northeast to east trades are elsewhere from 15N to 26N west
of about 126W. Seas are 6 to 8 ft with these winds.

Otherwise, high pressure of 1024 mb is analyzed north of the
area at 34N129W, with a ridge extending southeastward to
26N120W and to near 20N114W. The pressure gradient between the
ridge and relatively lower pressure to the south in the
subtropics and tropics is generally allowing for mostly moderate
trades from 16N to 23N between 120W and 126W. Gentle to moderate
trades are from 07N to 16N between 120W and 126W. Seas are 5 to
7 ft over these waters per latest satellite altimeter data
passes. Winds are moderate or weaker across the remainder of the
waters north of the Equator with seas of 5 to 7 ft, except seas
to 8 ft near the Equator between 97W and 122W. Moderate to fresh
southeast winds and seas of 7 to 9 ft are south of the Equator.
Any convection is described above in the monsoon trough/ITCZ
section.

For the forecast, moderate to fresh southeast winds will prevail
south of the Equator. Rough seas will pulse on either side near
the Equator to the east of about 130W over the next several days
in persistent and reinforced southerly swells.

Looking ahead, the remnant low of Tropical Depression Hernan
is forecast to move west of 140W Sun night while continuing to
weaken. Winds will diminish to mostly moderate speeds from 16N
to 23N west of 130W, with occasional gusts to fresh speeds
Sun night and seas over those waters will lower to around
5 to 6 ft. With regards to potential tropical cyclone formation,
an area of low pressure is expected form well to the west-
southwest of the southern tip of the Baja California Peninsula
by early next week. Environmental conditions appear conducive
for gradual development of this system and a tropical depression
could form around the middle of next week while it moves
generally westward across the western portion of the east
Pacific. Also, an area of low pressure could form several hundred
nautical miles south of the coast of southern Mexico near the
middle portion of next week. Some gradual development of this
system is possible, while the system moves westward or west-
northwestward well south of Mexico.

$$
Aguirre