Eastern Pacific Tropical Weather Discussion

306
AXPZ20 KNHC 121557
TWDEP 
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 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 1200 UTC surface analysis and satellite imagery through
1500 UTC.
...SPECIAL FEATURES...
Tropical Storm Norbert is centered near 17.3N 128.3W at 12/1500
UTC, moving west-northwest at 9 kt. Estimated minimum central
pressure is 999 mb. Maximum sustained wind speed is 50 kt with
gusts to 60 kt. Peak seas are 20 ft within 150 nm N semicircle 
of the center. Numerous moderate to 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): Earlier 
satellite-derived winds indicate that the surface circulation 
associated with an area of low pressure located several hundred 
miles southwest of the southwestern coast of Mexico remains 
poorly defined. Environmental conditions still 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 to minimal gale-force along 
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 90W north of 03N through Guatemala, 
moving west at 10 to 15 kt. Scattered moderate convection is 
active from 03N to 12N between 80W and 95W.
A tropical wave is along 114W from 07N to 20N, moving westward 
at 10 to 15 kt. A 1006 mb surface low (EP97) is along the wave 
axis near 15N114W. Numerous moderate convection is within 60 nm
of the center.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough extends from 10N85W to 07N95W to 16N115W to 
13N110W, and from 13N130W to beyond 13N140W. In addition to the 
convection associated with T.S. Norbert and Invest EP97, 
scattered moderate convection is found from 03N to 12N between 
80W and 95W, from 07N to 11N between 105W and 111W, and from 08N
to 16N between 116W and 125W. Scattered moderate to isolated 
strong is noted from 04N to 09N 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. 
The most recent scatterometer satellite pass confirmed fresh to 
strong winds near 1006 mb low pressure, Invest EP97, south of 
Clarion Island near 15.5N114W. Moderate to rough seas accompany 
these winds. The scatterometer pass also showed moderate to 
locally fresh NW winds off the coast of Colima and Michoacan. 
Farther north, 1003 mb low pressure is analyzed over the Colorado
River Valley between California and Arizona. This pattern is 
supporting moderate to fresh SE winds across the northern Gulf of
California, as noted in the scatterometer satellite pass. Gentle
to moderate winds and 3 to 5 ft seas are seen elsewhere. 
For the forecast, elsewhere, 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.
...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. A 1018 mb high pressure located
32N131W 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 118W to Baja California Peninsula.
For the forecast, Tropical Storm Norbert will move to 17.7N 
129.7W this evening, 18.1N 131.6W Sun morning, 18.4N 133.7W Sun 
evening, 18.6N 136.0W Mon morning, 18.7N 138.5W Mon evening, and 
18.6N 141.1W Tue morning. Norbert will weaken to a remnant low 
near 17.7N 146.3W early Wed. 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.