634 
AXPZ20 KNHC 130404
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Wed Sep 13 2023

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
0330 UTC.

...SPECIAL FEATURES...

A tropical wave is along 128W from 04N to 15N, moving W at 15 kt.
Disorganized scattered moderate isolated strong convection is
noted from 04N to 16N between 116W and 136W. Environmental 
conditions are conducive for development of this system during the 
next few days as it moves generally northwestward, and a 
tropical depression is likely to form later this week. The system
is then forecast to turn westward over the weekend, at which 
time further development is not anticipated. There is a medium 
chance of tropical cyclone formation within the next 48 hours. 
Refer to the latest NHC Tropical Weather Outlook at 
www.hurricanes.gov for more details.

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

The monsoon trough extends from 10N85.5W to 10N100W. The ITCZ 
continues from 10N100W to 12N110W to 11N124W to 09N127W. The ITCZ
continues west of the tropical wave from 06.5N130W to 03N140W.
Aside from the convection mentioned above in the Special Features
section, scattered moderate convection is noted from 05N to 08N
between 78W and 89W, and from 06N to 12N between 103W and 114W.

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

A ridge dominates the offshore forecast waters of Baja
California. Moderate to locally fresh NW to NNW winds extend to
the west of Baja California Norte with seas 6-7 ft, while gentle
to moderate NW winds are west of Baja California Sur with 5-6 ft
seas. Gentle S to SW winds are in the Gulf of California, with
seas of 1-3 ft. Fresh N winds are in the Gulf of Tehuantepec 
with seas to 7 ft. Light to gentle and variable winds prevail 
elsewhere with seas of 5-7 ft in long period S swell.

For the forecast, fresh N gap winds will prevail in the Gulf of 
Tehuantepec through Wed morning. Mainly moderate to locally fresh 
NW to N winds are forecast over the waters west of Baja 
California through the upcoming weekend. Seas are expected to 
build to 6 to 7 ft off Baja California Sur with these winds. 

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

Long period S to SW swell is affecting the waters offshore
Central America and northern South America. N of 05N, winds are 
light to gentle. South of 05N, gentle to moderate southerly 
winds prevail. Seas are 8-9 ft in between Ecuador and the 
Galapagos Islands based on altimeter data. Seas are 5-7 ft 
offshore Central America and Colombia, except up to 8 ft off 
southern Colombia, in long period S to SW swell.

For the forecast, southerly winds over the waters between 
Ecuador and the Galapagos Islands will increase Wed to moderate
to fresh and prevail through Thu before diminishing late in the
week. Seas of 8 to 9 ft in long period S to SW swell will
continue over these waters through Thu or Thu night before
subsiding. Elsewhere, light to gentle winds will prevail through
Fri night, except for moderate NE to E winds in the Gulf of 
Papagayo through early Wed morning. Long-period southerly swell,
with seas of 6-7 ft, will continue to propagate across the 
offshore waters of Central America through Wed night before 
gradually subsiding Thu and Thu night.

...REMAINDER OF THE AREA...

A surface trough is along 133W from 20N to 25N. An area of fresh
to strong NE winds remains between the northern end of the 
trough axis and a ridge to the N. Seas are 8 to 10 ft within 
these winds. Fresh winds and seas 7 to 8 ft are occurring in
association with the aforementioned tropical wave along 128W. 
Moderate to fresh SE to S winds are south of 06N between 100W 
and 130W, where seas are 8-10 ft in long period S swell. S swell
is reaching 8 ft as far north as 09N. Elsewhere, winds are 
moderate or weaker, with seas of 5-7 ft.

For the forecast, the surface trough near 133W will drift west- 
southwestward until it moves west of 140W Wed night. An area of 
fresh to strong winds between the trough and a high pressure to 
the N is forecast to persist through early Wed morning. Elsewhere
north of the ITCZ and E of 125W, mainly gentle to moderate NE to
E winds will prevail. To the south of 09N and east of 128W, seas
of 8 to 10 ft in long-period southerly swell will continue 
through tonight before gradually subsiding Wed through Thu night.

$$
Hagen