855 
AXPZ20 KNHC 171629 CCA
TWDEP 

Tropical Weather Discussion...Corrected
NWS National Hurricane Center Miami FL
1605 UTC Thu Sep 17 2026

Corrected Special Features section

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
1545 UTC.

...SPECIAL FEATURES...Corrected

Gulf of Tehuantepec Gale Warning: The pressure gradient between high
pressure over southern Mexico and the eastern north Pacific 
monsoon trough will support strong to near-gale force N to NE gap
winds across the Gulf of Tehuantepec into Fri. Winds earlier 
this morning were at gale-force, but have recently diminished to 
just below gale-force. Winds may again reach minimal gale force 
briefly tonight along with seas of 7 to 9 ft. Winds will continue 
to pulse in the Gulf at fresh to strong speeds through Sat
morning, with seas lowering to a peak of around 6 ft. 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 details.

...TROPICAL WAVES...

A tropical wave has is its axis along 97W from 05N northward 
to extreme southern Mexico. It is moving westward at around 10 
to 15 kt. Numerous moderate to isolated strong convection is 
from 09N to 13N between 90W and 98W. An area of low pressure 
could form in association to this wave well offshore of 
southwestern Mexico within the next few days. Environmental 
conditions appear conducive for some gradual development, and
a tropical depression is likely to form late this weekend or 
early next week while it gradually moves northwestward turning 
northward off the coast of southwestern Mexico.

The axis of a tropical wave is near 115W from 06N to 18N, moving
westward at 10 to 15 kt. Numerous moderate to strong convection
is seen from 07N to 11N between 111W-119W, and from 12.5N to 
16N between 114W and 17W. Environmental conditions appear 
conducive for gradual development of this system, and a tropical 
depression is likely to form this weekend or early next week as 
it moves westward  across the western part of the East Pacific.

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

The monsoon trough axis extends from along the coast of northwest 
Colombia west-southwest to across central Costa Rica, then to 
10N85W to 07N102W to 10N110W and to 13N121W. Scattered moderate 
to isolated strong convection is from 02N to 07N between 79W-95W.
Scattered moderate convection is within 120 nm north of the
trough between 103W-107W, and from 07N to 12N between 117W-121W.

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

Please see Special Features section above for details on a gale 
warning for the Gulf of Tehuantepec. 

An overnight scatterometer satellite data pass generally indicated
mostly gentle to moderate northwest winds across the central and 
southern sections of the Gulf of California. Seas are 2 to 4 ft 
in the Gulf, except for slightly higher seas of 3 to 5 ft at 
the entrance due to long-period southwest swell.

For the forecast, please see the Special Features section for 
information about the gale warning in the Gulf of Tehuantepec. 
Gentle to moderate breezes and moderate seas will persist 
elsewhere through the end of the week. Meanwhile, a tropical 
wave is producing disorganized showers and thunderstorms south of
Acapulco. Looking ahead, environmental conditions appear 
conducive for gradual development, and there is a high chance a 
tropical depression may form late this weekend or early next 
week while it moves north-northwestward or northward at 5 to 10 
kt off southwest Mexico.

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

Fresh to strong easterly winds, and moderate to rough seas, 
prevail across the Gulf of Papagayo region, extending downstream 
to near 92W. Moderate to fresh east winds extend downstream from
the Gulf of Papagayo to the outer offshore waters of El Salvador
and Guatemala. 

For the forecast, the pressure gradient between a ridge north
of the area and the eastern north Pacific monsoon trough will 
support pulsing fresh to occasionally strong easterly winds and 
moderate to rough seas across the Papagayo region today, then 
pulsing to moderate to fresh thereafter. Moderate winds and seas 
will prevail elsewhere.

...REMAINDER OF THE AREA...

The 1005 mb remnant low of Tropical Depression Fifteen-E is 
located near 15N132W. An overnight 0641Z scatterometer satellite
data pass shows fresh to strong northeast winds over the waters
to the northwest of the low pressure near 26N. Seas are 7 to 10
ft with these winds per overnight scatterometer satellite 
altimeter data. satellite imagery shows numerous strong 
convection from 14N to 17N between 129W and 135W. Scattered 
moderate to isolated strong convection is present from 06N
tom 09N between 130W and 135W, and from 13N to 18N between
123W and 128W. Scattered moderate convection is within 
30 nm of a line from 06N to 09N between 130W and 135W. Fresh to 
strong winds, and rough seas, supported by the pressure gradient 
between the area of low pressure and the subtropical ridge north 
of the area, cover the waters from 15N to 25N west of 125W. 
Gentle to moderate winds and 4 to ft combined seas in mixed 
swell are noted elsewhere. 

For the forecast, environmental conditions appear conducive for 
gradual development of the tropical wave along 115W, and a 
tropical depression is likely to form this weekend or early next
week as it moves westward across the western part of the East 
Pacific. Farther west, a broad area of fresh to strong northeast
to east winds and moderate to rough seas in north swell will 
persist through the remainder of the week from 15N to 25N west of
125W. Also, as described in the tropical wave section above, 
there is some potential for tropical cyclone development 
associated with a tropical wave near 97W.

$$
Aguirre