000
AXPZ20 KNHC 251549
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Sat Sep 25 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 1200 UTC surface analysis and satellite imagery through
1510 UTC.

...TROPICAL WAVES...

The axis of a tropical wave previously analyzed near 129W has
been dropped from the 1200 UTC analysis. No clear signal of this
wave is presently obvious across this area.

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

The monsoon trough extends from 1010 mb low pressure over coastal
Colombia near 10.5N74.5W to 08.5N89W to low pres 1009 mb near 
11N119W to 10N131W. The ITCZ extends from 10N131W to beyond 
09N140W. Scattered moderate to strong convection is noted N of 
06.5N E of 81W, from 05.5N to 16N between 90W and 102W, from 
09.5N to 15.5N between 107W and 121W, and from 07N to 17N between
121W and 132W.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Fresh to strong N-NE winds continue this morning across the Gulf
of Tehuantepec with seas of 6 to 8 ft. Gentle to moderate NW-N 
winds are noted west of Baja California and also offshore of Cabo
Corrientes. Light to gentle winds are elsewhere offshore of 
Mexico. Seas are 4 to 6 ft in a mixed of long period swells 
offshore of Mexico, except 3 ft or less in the central and 
northern Gulf of California.

Fresh to strong northerly gap winds will continue in the Gulf of
Tehuantepec through Sun. Mainly moderate NW-N winds will prevail
west of Baja California, pulsing locally 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. New large NW swell may 
impact the waters west of Baja California by the middle of next 
week as a cold front enters the waters well west of 120W.

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

Moderate to fresh offshore winds prevail this morning 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.

Moderate to fresh offshore winds will pulse in the Papagayo 
region, briefly to fresh to strong tonight and Sun night. 
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 
waters through early next week.

REMAINDER OF THE AREA...

A 1011 mb low pressure center previously analyzed near 20N128W 
has opened up into a trough, along 128-129W from 17N to 21.5N. 
Isolated moderate convection is noted north of the trough along 
23N. Moderate to locally fresh NE-E winds are also noted N 
through W of the trough. Broad and week 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 8 ft south of 11N, except to 9 ft in
southerly swell south of the equator and west of 95W.

Winds associated with the trough along 128W-129W will gradually 
diminish over the weekend 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. Associated 
long period NW swell is expected to build seas to 8 to 11 ft, 
spreading southward through the middle of next week.

$$
Stripling