000
AXPZ20 KNHC 260132
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Sun Sep 26 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 0000 UTC surface analysis and satellite imagery through
0100 UTC.

...TROPICAL WAVES...

A tropical wave is along 95W/96W, from 02N to 15N, moving west 
at 10 to 15 kt. Precipitable water animations and wave 
diagnostics show a clear wave signal propagating westward off of 
Central America the past two days. Associated convection is
described below.

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

The monsoon trough extends from northern Colombia from 11N74W to
across northern Costa Rica to 10N86W to 09N97W to 12N120W to
09N134W. The ITCZ extends from 09N134W to 09N140W. Isolated to
scattered moderate to strong convection is noted from 05N to 14N
between 92W and 104W, and within 13N133W to 17N120W to 15N114W to
04N127W to 05N137W to 13N133W. Isolated to scattered moderate 
convection is noted from 08N to 14N between 106W and 113W.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Fresh to near gale force N-NE winds are noted in the Gulf of
Tehuantepec along with seas of 5 to 8 ft. Moderate NW-N winds are
noted west of Baja California and in the central and southern
Gulf of California. Light to gentle winds are noted elsewhere.
Seas are 4 to 7 ft across the remainder of the open waters, and 2
to 4 ft in the Gulf of California, except 3 ft or less in the
northern Gulf.

For the forecast, fresh to strong northerly gap winds will 
continue across the Gulf of Tehuantepec through Sun night.
Mainly moderate NW-N winds will prevail west of Baja California,
pulsing to fresh during the afternoon through evening hours. 
S-SW winds will pulse to moderate to fresh in the northern Gulf 
of California. Otherwise, gentle to moderate winds will prevail. 
Large NW swell will impact the waters west of Baja California by 
late Tue as a cold front sinks southward through Wed. Seas are 
expected to peak at 8 to 11 ft across the Baja California Norte 
waters Wed morning.

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

Moderate to fresh offshore winds prevail across the Papagayo 
region, with light to gentle winds elsewhere north of the monsoon
trough. Gentle to moderate S-SW winds are south of the monsoon 
trough. Seas are in the 4 to 6 ft range from offshore of Colombia
northward, and 5 to 7 ft in building SW swell offshore of 
Ecuador.

For the forecast, moderate to fresh offshore winds will pulse 
across the Papagayo region. Otherwise, light to gentle winds will
prevail north of the monsoon trough, with mainly moderate winds 
south of the monsoon trough. Cross equatorial SW swell will 
propagate through the regional waters through early Tue.

REMAINDER OF THE AREA...

A surface trough is along 130W from 16N to 21N. Isolated 
moderate convection is noted north of the trough from 22N to 23N.
Moderate to locally fresh NE-E winds are west of the trough. 
Broad and weak ridging and gentle to moderate trades dominate 
the remainder of the open waters north of the convergence zone. 
Gentle to moderate southerly winds prevail south of the 
convergence zone. Seas are in the 5 to 7 ft range north of 11N, 
and 6 to 7 ft south of 11N, except locally to 8 ft between 93W
and 120W.

For the forecast, winds associated with the trough along 130W 
will gradually diminish through late Sun as it shifts westward 
and weakens. A cold front is expected to move into the NW waters 
Mon night into early Tue and quickly weaken as it moves southward
and gradually dissipates along 21N by the end of the week. 
Associated long period NW swell is expected to build seas to 8 to
11 ft to the west of 120W, spreading southward through the 
middle of this coming week.

$$
Lewitsky