Eastern North Pacific Tropical Weather Discussion

358 
AXPZ20 KNHC 120353
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Sat Sep 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 0000 UTC surface analysis and satellite imagery through
0300 UTC.

...SPECIAL FEATURES...

Tropical Storm Norbert is centered near 17.2N 126.6W at 12/0300
UTC, moving west-northwest at 10 kt. Estimated minimum central
pressure is 996 mb. Maximum sustained wind speed is 55 kt with
gusts to 65 kt. Peak seas are 24 ft within 150 nm NE quadrant of
the center. Numerous moderate to strong convection is noted from
within 180 nm NE and 90 nm SW semicircles. Norbert will continue
to move to the west- northwest over the next couple of days. 
Some strengthening is forecast during the next 48 hours, and 
Norbert could become a hurricane by late Sat.

Please read the latest HIGH SEAS FORECAST issued by the National
Hurricane Center at website - 
https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest 
Fourteen-E NHC Forecast/Advisory and Public Advisory at 
www.hurricanes.gov for more details.

Gale Warning south of Clarion Island (EP97): Showers and 
thunderstorms continue to become better organized in association 
with a broad area of low pressure located several hundred miles 
southwest of the southwestern coast of Mexico. Gradual 
development of this system is likely, and a tropical depression 
is expected to form during the next day or two while it moves 
generally west-northwestward to westward over the central and 
western portions of the eastern Pacific basin. This system has a 
high chance of tropical cyclone formation within the next 48 
hours. Regardless of tropical cyclone development, winds to
minimal gale-force along with rough seas are expected about 120
nm south and southwest of Clarion Island by late Sun.

Refer to the latest NHC Tropical Weather Outlook at website -
www.hurricanes.gov for more details.

...TROPICAL WAVES...

A tropical wave is along 86W north of 08N, moving west at 10 to
15 kt. Scattered moderate convection is active from 05N to 08N
between 83W and 87W. 

A tropical wave is along 113W/114W from 07N to 20N, moving 
westward at 10 to 15 kt. A 1009 mb surface low (EP97) is along 
the wave axis near 14N114W. Scattered moderate convection is 
present from 11N to 14N between 111W and 117W. 

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

The monsoon trough extends from 08N78W to 09N85W to 10N110W to
16N118W, and from 12N125W to 15N140W. In addition to the 
convection associated with T.S. Norbert and Invest EP97, 
scattered moderate convection is found from 06N to 11N between
90W and 100W.

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

Please see the Special Features section for more information 
about Tropical Storm Norbert and Invest EP97. 

Fresh to strong winds and building seas are likely within 120 nm
to the northeast of the 1008 mb low pressure area near 14N114W,
reaching the outer offshore waters south of the Revillagigedo
Islands. Farther north, 1000 mb low pressure is analyzed over the
Colorado River Valley between California and Arizona. This
pattern is supporting moderate to possibly locally fresh SE winds
across the northern Gulf of California. Gentle to moderate winds
and 3-5 ft seas are noted elsewhere. 

For the forecast, a ridge will build across the offshore waters 
of Baja California, bringing moderate to locally fresh NW to N 
winds Sun into early next week. Expect fresh winds across the 
northern Gulf of California early next week likely due to the 
pressure gradient between the ridge and the meandering trough 
that is in place in that area. Fresh to strong N to NE gap winds 
will pulse again in the Tehuantepec region early next week. 
Meanwhile, showers and thunderstorms are becoming better 
organized in association with a broad area of low pressure (EP97)
located several miles southwest of the southwestern coast of 
Mexico. Gradual development of this system is likely, and a 
tropical depression is expected to form late this weekend or 
early next week while it moves generally west- northwestward to 
westward over the central and western portions of the East 
Pacific. Regardless of tropical development, interests south of the
Clarion Island may see fresh to strong SE winds and rough seas by
late Sun as the low pressure moves W-NW to the south of the
island.

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

High pressure north of the area is promoting fresh to strong 
easterly trade winds and rough seas across the Gulf of Papagayo 
region, extending downstream to near 89W. Elsewhere, moderate or 
weaker winds and moderate seas are prevalent. Scattered showers 
and thunderstorms are occurring off Panama and Colombia. Gusty 
winds and higher seas are likely occurring with these storms.

For the forecast, a ridge north of the area will continue to
support pulsing fresh to strong easterly winds and moderate to 
rough seas across the Papagayo region through early next week. 
Meanwhile, gentle to moderate southerly winds and moderate seas 
are expected over the waters between Ecuador and the Galapagos 
through at least the middle of next week. Moderate or lighter 
winds and moderate seas in long period SW swell are forecast 
elsewhere.

...REMAINDER OF THE AREA...

Please see the Special Features section for more information 
about Tropical Storm Norbert and Invest EP97.

Away from the impacts of T.S. Norbert, moderate to locally fresh
SE winds and rough seas are found south of 04N and west of the 
Galapagos Islands to about 130W. 1020 mb high pressure located 
32N132W dominates waters north of 20N. Under the influence of 
this system, and away from Norbert, mainly moderate winds and 
moderate seas prevail, with the exception of light to gentle 
winds north of 20N and east of 115W to Baja California 
Peninsula.

For the forecast, Tropical Storm Norbert is near 17.2N 126.6W at 8 PM PDT, and is
moving west-northwest at 10 kt. Maximum sustained winds are 55
kt with gusts to 65 kt, and the minimum central pressure is 996
mb. Norbert will move to 17.4N 127.9W Sat morning, strengthen to
a hurricane near 17.8N 129.8W Sat evening, 18.2N 131.5W Sun
morning, 18.5N 133.3W Sun evening, weaken to a tropical storm
near 18.7N 135.5W Mon morning, and 18.6N 137.3W Mon evening.
Norbert will change little in intensity as it moves to the west
of 140W by late Tue. Elsewhere, a cross equatorial swell will 
persist over the next several days producing seas to 9 ft south 
of 04N. A tight pressure gradient will result in locally fresh N 
winds and rough seas in the NE waters late this weekend into 
early next week. 

$$
Christensen