000
AXPZ20 KNHC 182035
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Mon Dec 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 1800 UTC surface analysis and satellite imagery through
2030 UTC.

...SPECIAL FEATURES...

Gulf of Tehuantepec Gale Warning: The pressure gradient between
high pressure along the eastern slopes of Mexico and the eastern
north Pacific monsoon trough is supporting gale-force north to 
northeast winds of 30-40 kt in the Gulf of Tehuantepec, with 
seas peaking at around 12 ft. A tight pressure gradient will 
support gale conditions through much of the week. Seas with this 
latest gale-force gap wind event are forecast to peak near 15 ft 
late tonight and Tue.

Eastern Pacific Significant Swell event: The NW swell over the 
far NW waters has subsided below 12 ft. A new set of northwest 
swell will move into the northwest waters midweek, and seas 
greater than 12 ft will move into the northern waters on 
Wednesday. Seas with this swell event will peak near 14 or 15 ft 
over the waters north of 29N between 125W-132W late Wed and early
Thu before starting to subside. 

Please read the latest NWS High Seas Forecast issued by the 
National Hurricane Center at 
https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details.

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

The monsoon trough extends from 09N84W to 05N95W. The ITCZ 
continues from 05N95W to 08N120W to 08N140W. Scattered moderate 
convection is noted from 01N to 10N between 110W and 132W. 

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

Please see the Special Features section for details on the 
ongoing Gulf of Tehuantepec Gale Warning.

Aside from the Gulf of Tehuantepec, light to gentle northwest 
winds, and seas of 1-3 ft, are over the Gulf of California. A 
weak pressure gradient dominates the Mexican offshore waters 
outside of the Gulf of Tehuantepec, with mainly light to gentle
winds across the rest of the offshore waters. Seas are in the 
6-8 ft range in long- period west to northwest swell off the 
Baja California peninsula, and 4-5 ft elsewhere.

For the forecast, NW swell over the outer offshore forecast 
waters of Baja California between Cabo San Lazaro and Punta 
Eugenia will subside on Tue. Low pressure may approach far 
northern Baja California Norte from the W on Fri bringing fresh 
west to northwest winds. A large set of northwest swell will 
begin to impact the waters west of Baja California Norte Thu, 
spreading across the Baja California Sur offshores Fri and Sat.

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

Fresh to strong winds are over the Gulf of Papagayo, with fresh 
winds extending downstream of the Gulf to near 90W. Seas of 6-7 
ft are over and downstream of the Gulf of Papagayo region. 
Northwest swell generated by the Gulf of Tehuantepec gale-force 
gap wind event is supporting seas in the 6-8 ft range over the 
outer offshore waters of Guatemala and El Salvador. Moderate to 
fresh north winds, and seas of 5-6 ft, are over the Gulf of 
Panama. Gentle winds, and seas of 4-5 ft, are elsewhere south of 
the monsoon trough.

For the forecast, fresh to strong northeast to east winds in the
Gulf of Papagayo will continue through the week, with periods of
near gale force through early Thu. Winds will diminish Sat. NW 
swell generated by the Gulf of Tehuantepec gale- force gap wind 
event will impact the outer Guatemala and El Salvador offshore 
waters for much of the week. Moderate to fresh north winds are 
over the Gulf of Panama, reaching strong speeds tonight through 
early Wed. Elsewhere, winds are expected to be moderate or weaker
for the next several days. 

...REMAINDER OF THE AREA...

Please see above for details on an upcoming significant swell 
event over the western portion of the basin.

A cold front extends from 30N123W to 23N127W. Moderate winds are
west of the front as well as within 120 nm east of the front. 
Moderate to locally fresh trades are N of the ITCZ to near 15N. 
Light to gentle winds are elsewhere N of the ITCZ. Gentle to 
moderate winds prevail S of the ITCZ. Seas of 8-11 ft are found 
over the waters N of 04N and W of 120W. Seas of 5-7 ft are
elsewhere over the discussion waters. 

For the forecast, winds south of the ITCZ will be in the 
moderate to fresh range through midweek. The 8 ft seas from the 
northwest swell over the western waters will gradually subside, 
with areal coverage of 8 ft seas decreasing over the next few
days.

$$
AL