000
AXPZ20 KNHC 172200
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Tue Jan 17 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 1800 UTC surface analysis and satellite imagery through
2145 UTC.

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

The monsoon trough extends from NW Colombia near 10N75W, westward
to southern Costa Rica, continues west-southwestward to 07N93W 
to 08N100W to low pressure of 1012 mb near 07N103W to 04N110W and
to 05N120W, where latest scatterometer data indicates that it 
transitions to the ITCZ to 07N128W, where it is interrupted by a
trough that extends from 10N127W to 04N132W. The ITCZ resumes at
07N132W and continues to beyond 06N140W. Scattered moderate 
convection is seen within 120 nm south of the south of the trough
between 91W-97w.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

A cold front is pushing across the central Gulf of California 
and Baja California Sur. Southwest to west of 20-25 kt are south
of the front over the Gulf of California to near 29N along with 
seas of 4-6 ft. Moderate to fresh west to northwest are noted 
from 28N to 29N. Gentle to moderate south to southwest winds are 
over the central section of the Gulf, while gentle northwest to 
north winds are over the southern section of the Gulf. Seas of 
4-6 ft are over the northern section of the Gulf, while seas of 
3-4 ft are elsewhere over the Gulf. 

A ridge dominates the offshore waters of Baja California Sur. 
Fresh northwest winds are west of the northern and central 
sections of the Baja California Peninsula, while moderate
to fresh northwest to north winds are west of Baja California 
Sur, except from Cabo San Lucas to Cabo San Lazaro, where winds 
are slighter lighter, mostly moderate in speeds. These winds 
extend southward to near 15N. Similar winds are along the coast 
of Mexico between Manzanillo and Cabo Corrientes. In the Gulf of 
Tehuantepec region, gentle southerly winds are present there.
Long-period northwest swell continues to propagate across most 
of the offshore forecast waters of Mexico, with seas of 9-12 ft 
north of Punta Eugenia except 10-13 ft north of 28N, and 8-11 ft
between Cabo San Lazaro and Punta Eugenia. Seas of 6-8 ft are 
noted elsewhere.

For the forecast, fresh to strong winds will persist in the
northern Gulf of California will exist from 29N to 30N between 
112W-114W by early this evening, with seas of about 3-5 ft as the 
front slides farther to the east and southeast. These conditions
then diminish by around 12Z Wed as the front weakens while it 
clears the rest of the Gulf of California. Light to gentle winds 
will prevail in the Tehuantepec region through the week along 
with 4-6 ft seas. Long-period northwest swell will continue to 
propagate over the offshore waters of the Baja California 
Peninsula tonight through early Wed, with seas of 8-11 ft. The 
leading edge of the swell is expected to reach the vicinity of 
the Revillagigedo Islands by early Wed afternoon. Afterward, the
swell will slowly subside through late Thu allowing for seas to 
lower to 6-8 ft.

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

Mostly fresh northeast to east winds are in the Gulf of 
Papagayo. Gentle to moderate northerly winds are in the Gulf of 
Panama and near the Azuero Peninsula. Light to gentle winds are 
noted per scatterometer data elsewhere. Long-period northwest 
swell propagating through these waters has raised seas to the 
range of 6-8 ft over the offshore waters from northern Costa Rica
to Guatemala per latest altimeter data over these waters. Elsewhere,
seas are generally in the 4-6 ft range. 

For the forecast, mainly moderate to fresh winds will prevail in
the Papagayo region through Fri, then winds are forecast to
increase again to fresh to strong speeds Fri night and Sat. 
Gentle to moderate winds are expected in the Gulf of Panama, and 
east of the Azuero Peninsula the remainder of the work-week. Seas
from northern Costa Rica to Guatemala offshore waters subsided
to 5-6 ft, while seas of 5-8 ft due to a long-period northwest 
swell are over the waters between Ecuador and the Galapagos 
Islands. Winds will be moderate or weaker elsewhere through at 
least the next several days.

REMAINDER OF THE AREA...

As previously mentioned, a cold front extends from Baja
California Sur southwestward to near 21N120W, where it
transitions to a dissipating front to to 21N139W. Winds behind 
the front are of fresh speeds and northwest in direction. Long- 
period northwest swell producing seas in the range of 9-12 ft, 
with the exception 10-13 ft seas north of 28N east of 124W is 
propagating through the waters behind the front. Elsewhere, a 
surface ridge dominates the waters north of 10N west of about 
110W. Light to gentle winds under the influence of the ridge, 
except for moderate to fresh northeast winds confined to the 
southern periphery of the ridge, where a tighter pressure 
gradient exists between the ITCZ and 15N. Previous long-period 
northwest swell that in previous days had moved through the 
western and central waters is over the waters southeast and south
of the front reaching to near 05N. Associated seas are of 8-9 
ft. This swell is forecast decay through Thu, with the residual 
merging with the newer swell set that is being the aforementioned
cold front.

For the forecast, large and long-period northwest swell will 
continue to propagate across most of the forecast waters through 
Thu while slowly decaying allowing for a subsiding trend of the 
seas. The cold front is forecast to dissipate in about 24 hours 
while reaching the waters near 18N. At that time, a remnant 
frontal trough, is likely to be the analyzed feature. The fresh 
northwest winds behind the front are forecast to become gentle to
moderate north to northeast winds tonight into Wed as the front 
moves to just south of Baja California and extends westward along
or near 19N to 125W. These winds change little going into Thu as
the front weakens to a remnant frontal trough, and as seas 
continue to subside. Behind the trough, trade winds increase 
some Thu over the western part of the area between the ITCZ and 
25N as high pressure builds eastward roughly along 30N. 

$$
Aguirre