653
AXPZ20 KNHC 180321
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Wed Sep 18 2024

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
0200 UTC.

...TROPICAL WAVES...

A tropical wave is along 94W extending from Chiapas, Mexico
southward over the eastern Pacific to near 06N, moving westward
at 10 kt. Scattered moderate to strong convection is described
below, and is noted within 180 nm either side of the trough
axis.

A tropical wave is along 110W from 16N to near 06N, moving
westward at about 10 kt. Scattered moderate isolated strong
convection is noted from 14N-16N between 109W-113W, and widely
scattered along the monsoon trough between 107W and 110W.

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

The monsoon trough extends from 11N73.5W to 11N83W to 09N96W to
11.5N104W to 08.5N123W, where it transitions to the ITCZ, and
continues to 10.5N131W to beyond 08N140W. Scattered moderate to
strong convection is noted from 06.5N-12N between 81W and 104W,
from 08N-11N between 107-128W, and from 08N-13N west of 128W.
Scattered to locally numerous moderate to strong convection is
noted within 75 nm of the coasts from central Nicaragua along 86W
to Jalisco, Mexico along 105W.

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

A broad surface ridge extends southeastward into the region
through 30N126W to 19N109W. Over the waters west of the Baja
California peninsula, moderate to fresh NW winds prevail, with
small areas of strong winds along the coast N of 26N. Seas are
4 to 5 ft in moderate period swell except to 6 ft in the areas of
strong winds. Moderate NW to N winds prevail elsewhere to the
south across the Revillagigedo Islands to Manzanillo. Light to
gentle NW to W winds cover the remaining waters eastward to
Tehuantepec. Seas sough of 20N are 4 ft in long period SW swell.
Variable winds at 12 kt or less dominate the Gulf of California
this evening, with seas of 1 to 3 ft, except to 4 ft in SW swell
across the entrance.

For the forecast, the current Pacific ridge will remain in place
and fluctuate throughout the week. This pattern will produce
moderate to fresh NW to N winds over the near and offshore waters
of the Baja California peninsula tonight, weakening by Wed
morning to moderate through Wed night, then weakening slightly
on Thu. High pressure will strengthen modestly Fri and Sat to
bring a return to moderate to fresh winds. Variable winds less
than 15 kt are expected across the Gulf of California, except for
pulses of moderate to fresh SW gaps winds N of 30N each evening
and night.

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

Gentle to moderate SW to W winds are occurring south of the
monsoon trough, along about 10N. North of the monsoon trough,
moderate or weaker winds are observed, with moderate easterly gap
winds flowing across the Papagayo region. Seas are 4-5 ft in SW
swell except to 6 ft south through west of the Galapagos
Islands. Scattered strong convection occurring to the east of a
tropical wave along 94W is moving westward across Central
America, and into the waters within 75 nm of the coasts between
NW Nicaragua and Tehuantepec.

For the forecast, gentle to moderate SW to W winds will continue
south of the monsoon trough near 10N through tomorrow afternoon,
then begin to freshen Thu through Sat. Seas will build to 5 to 7
ft during this time in a mix of SW swell and westerly wind swell.
Active weather is expected south of 10N Fri into the weekend.
North of the monsoon trough, moderate or weaker winds are
expected for the next several days.

...REMAINDER OF THE AREA...

Surface ridging from a 1031 mb high centered near 38N156W
extends east-southeastward to 30N126W to offshore of Cabo
Corrientes near 19N109W. The pressure gradient between the ridge
and the ITCZ/monsoon trough to the south is forcing moderate to
locally fresh NE trades, strongest from 12N to 22N west of 132W.
Seas are 6-7 ft in mixed swell south of 17N west of 128W, and 4-6
ft elsewhere.

For the forecast, little overall change is expected over the
open Pacific waters for the next several days, as the ridge
dominates the region. A weak cold front will sink across 30N east
of 130W Wed night and push southeastward before dissipating by
Fri morning. This will induce a slight decrease in winds during
that time period, with winds then increasing slightly Fri
through Sat.

$$
Stripling