367 
AXPZ20 KNHC 092121
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Fri Jul 9 2021

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.

...TROPICAL WAVES...

The axis of a tropical wave extends along 85W and north of 04N 
continuing, moving W at around 10 kt. Scattered to numerous 
moderate convection prevails in the area enhanced by the monsoon
trough from 05N-13N and east of 100W.

The axis of a tropical wave extends along 105W from 08N to 18N, 
moving W at around 10 kt. Scattered moderate convection is noted 
from 03N to 15N between 104W and 110W.

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

The monsoon trough extends from 10N85W to 16N110W to low 
pressure near 15N112W 1011 mb to low pressure near 10N127W 1013 
mb to low pressure near 09N136W 1012 mb. Aside from the
convection described above, scattered moderate prevails from 06N
to 12N between 110W and 136W.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Light to gentle winds dominate the offshore waters of Mexico with
a broad surface ridge west of Baja California. Gentle to 
moderate southerly winds prevail in the Gulf of California with 
locally fresh in the northern Gulf in addition to the southern 
tip of Baja. Seas are mainly in the 5 to 7 ft range in long 
period southerly swell. Seas are 3 ft or less in the Gulf of 
California, higher near the entrance due to the southerly swell.

For the forecast, a ridge will continue to dominate the waters W
of Baja California peninsula during the next several days. This
will give way to producing gentle to moderate NW-N winds through
the weekend. Farther south, light to gentle breezes will persist
off southern Mexico through the weekend. In the Gulf of 
California, fresh to strong winds are possible late in the 
weekend into early next week over the northern half. Fresh to 
strong northerly winds could develop in the Gulf of Tehuantepec 
by Sun night and continue through midweek. A moderate long 
period southerly swell will gradually subside through the 
weekend. 

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

Moderate to fresh NE-E winds and seas to 7 ft are noted in the 
Papagayo region. Light winds are north of the monsoon trough with
gentle to moderate winds south of the monsoon trough. Seas are 
in the 5 to 8 ft range. The higher seas are reaching near Ecuador
and the Galapagos Islands.

For the forecast, fresh to strong winds will pulse across the 
Papagayo region through the weekend, supporting seas to 8 ft 
downstream. Elsewhere, moderate to locally fresh southerly flow 
will prevail south of 10N through Fri, with light to gentle 
breezes north of 10N. Cross equatorial SW swell is forecast to 
reach the waters between Ecuador and the Galapagos Islands late
this weekend, building seas 8 to 9 ft as north as the offshore 
waters of western Panama. 

REMAINDER OF THE AREA...

A surface ridge extends across the waters north of the 
convergence zone. The pressure gradient between the ridge and 
lower pressure along the convergence zone is supporting gentle to
moderate winds north of it, with moderate to fresh winds south 
of it. Seas are in the 5 to 8 ft range based on altimeter data in
mixed long period swell. 

For the forecast, little change in winds and seas are forecast
through the weekend. Fresh winds could develop over the waters N
of 25N and W of 130W on Sat and continue into Mon. The ridge 
will erode westward this weekend as a weak trough develops west 
of Baja California, shifting westward into early next week. This 
will allow for the trades to relax by that time. 

$$
ERA