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Eastern North Pacific Tropical Weather Discussion


000
AXPZ20 KNHC 122131
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 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 1800 UTC surface analysis and satellite imagery through
2100 UTC.

...SPECIAL FEATURES...

Tropical Storm Norbert is centered near 17.6N 129.6W at 12/2100
UTC, moving west-northwest at 10 kt. Estimated minimum central
pressure is 1000 mb. Maximum sustained wind speed is 45 kt with
gusts to 55 kt. Peak seas are 20 ft within 150 nm N semicircle 
of the center. Numerous moderate to scattered strong convection 
is noted within 150 nm NW semicircle. Norbert is moving toward 
the west- northwest. A turn toward the west is forecast on 
Sunday, and Norbert should continue in this direction during the 
next several days. Only modest strengthening is expected through 
the weekend. By early next week, a gradual weakening trend is 
expected to commence, and Norbert should degenerate into a post- 
tropical remnant low toward the end of next week.

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 (Invest EP97): Showers and 
thunderstorms associated with an area of low pressure located 
several hundred miles southwest of the southwestern coast of 
Mexico have become a little less organized this morning. 
Environmental conditions appear conducive for development, 
however, and a tropical depression is expected to form during the
next couple of days 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. A Gale Warning is in effect 
with this system. Regardless of tropical cyclone development, 
winds strong winds with rough seas are expected to the south and
southwest of Clarion Island through Mon.

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

...TROPICAL WAVES...

A tropical wave is along 91W north of 03N extending into Guatemala,
moving west at 10 to 15 kt. Scattered moderate to isolated strong 
convection is active from 04N to 12N between 83W and 98W.

A tropical wave is along 114W from 07N to 20N, moving westward 
at 10 to 15 kt. A 1008 mb surface low (EP97) is along the wave 
axis near 17N114W. A well defined swirl of low clouds is evident
in visible satellite imagery in association with this low.

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

The monsoon trough extends from 10N85W to 05N100W to 16N115W to 
11N110W, and from 12N130W to beyond 13N140W. In addition to the 
convection associated with T.S. Norbert and Invest EP97, 
scattered moderate convection is found from 04N to 12N between 
83W and 98W, from 07N to 11N between 105W and 112W, and from 07N
to 14N between 117W and 125W. Scattered moderate to isolated 
strong is noted from 04N to 10N W of 130W.

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

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

Recent scatterometer satellite pass indicates fresh to strong 
winds within 90 nm on the E semicircle of Invest EP97, that is a
1008 mb low pressure, located south of Clarion Island near 
17N114W. Moderate to locally rough seas accompany these winds. 
Scatterometer data also show moderate to locally fresh NW winds 
off the coast of SW Mexico. Similar winds speeds are also noted 
over the northern Gulf of California. Light to gentle winds and 
moderate seas dominate the offshore forecast waters of Baja 
California. 

For the forecast, away from the impacts of T.S. Norbert and 
Invest EP97, 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 due to the pressure gradient 
between the ridge and lower pressure over the Colorado River 
valley. Looking ahead, fresh to strong N to NE gap winds will 
pulse again in the Tehuantepec region by the middle of next week,
building seas to 8 or 9 ft.

...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 90W. Elsewhere, moderate or
weaker winds and moderate seas are prevalent. Convection continues
to develop on either side of the monsoon trough. Gusty winds and
higher seas are likely occurring near thunderstorms. 

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 135W. A 1020 mb high pressure located
N of area near 34N133W dominates the 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 116W to Baja 
California Peninsula.

For the forecast, Tropical Storm Norbert will move to 18.0N 131.1W 
Sun morning, 18.5N 133.2W Sun afternoon, 18.8N 135.4W Mon morning,
19.1N 138.0W Mon afternoon, 19.3N 140.7W Tue morning, and weaken
to a tropical depression near 19.3N 143.4W Tue afternoon. Norbert
will become a remnant low well W of area to near 18.5N 149.0W 
Wed afternoon. 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. 

$$
GR