000
AXPZ20 KNHC 180832
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Mon Sep 18 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 0600 UTC surface analysis and satellite imagery through
0830 UTC.

...SPECIAL FEATURE...

A tropical wave extends its axis near 113W S of 17N, moving W at
10 kt. Scattered moderate and isolated strong convection is from
08N-17N between 110W-120W. Environmental conditions are expected 
to be conducive for gradual development during the next few 
days, and a tropical depression is likely to form by the mid to 
latter part of this week while the system moves west- 
northwestward over the central and western portions of the basin.
There is a medium probability of tropical cyclone development 
with this system over the next 2 days, and a high probability of 
tropical cyclone development in the next 7 days.

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

The monsoon trough extends from 09N84W to 09N92W to 13N112W to 
10N130W to 10N140W. Scattered moderate isolated strong 
convection is noted from 04N to 12N and E of 105W, and from 07N
to 13N between 120W and 140W.

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

A surface ridge dominates the offshore forecast waters of Baja 
California supporting moderate to fresh NW winds and seas of 5 
to 7 ft. In the Gulf of California, light to gentle winds 
prevail. Seas are 1-3 ft, except 3-4 ft near to the entrance of 
the Gulf. Moderate to fresh winds are noted in the Gulf of 
Tehuantepec. Light to gentle winds, and seas of 5-6 ft in S to SW
swell, prevail elsewhere across the Mexican offshore waters.

For the forecast, the surface ridge will remain in control of the
weather pattern across the region over the next several days.
Moderate to fresh NW to N winds will prevail over the waters
west of Baja California through the early part of the week, with
seas of 6 to 7 ft. Fresh to strong winds in the Gulf of 
Tehuantepec will diminish Tue.  

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

Moderate to fresh gap winds are noted over and downstream of the
Gulf of Papagayo, with light to gentle winds elsewhere N of the 
monsoon trough. S of the monsoon trough, gentle winds prevail, 
reaching moderate speeds between Ecuador and Colombia. Seas are 
4-6 ft.

For the forecast, gentle to moderate southerly winds over the 
waters between Ecuador and the Galapagos Islands will prevail 
through mid week before diminishing. Moderate to fresh gap winds 
will prevail in the Gulf of Papagayo through Tue before 
diminishing slightly. Elsewhere, light to gentle winds will 
prevail. 

...REMAINDER OF THE AREA...

Refer to the section above for details on the developing tropical
wave near 111W. 

Moderate to locally fresh winds and seas to 8 ft are impacting 
the waters from 15N to 18N and W of 138W. Gentle to moderate 
southerly winds are south of 05N. Seas are 5-8 ft in long period 
SE swell south of 05N and east of 120W. Elsewhere, winds are 
moderate or weaker with seas of 4-7 ft. 

For the forecast, winds and seas will start to increase by the
middle of the week in associated to the tropical wave discussed
above. Elsewhere, high pressure will prevail across the northern
waters, particularly N of 15N and W of 110W. Under the influence
of this system, gentle to moderate anticyclonic flow is expected
with seas in the 4-7 ft range. South of 05N, moderate southerly 
winds will prevail, with moderate southerly swell persisting 
through the weekend.

$$
AL