000
AXPZ20 KNHC 160920
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Thu Dec 16 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 0600 UTC surface analysis and satellite imagery through
0840 UTC.

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

The monsoon trough extends from 09.5N75W to 10.5N81W to 06N102W.
The ITCZ extends from 06N102W to 08N110W, then resumes W of a 
surface trough from 09N114W to 09.4N124W, then resumes W of a 
surface trough from 08.5N129W to beyond 07N140W. Scattered 
moderate isolated strong convection is noted from 06N to 08N 
between 91W and 104W, and from 06.5N to 12N between 107W and 123W.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO

A high pressure ridge along 30N to 33N west of the area continues
to settle across the region tonight, and extends SE to near
18N111W. The ridge is forcing fresh NNW winds within 120 nm of 
the Pacific coast of Baja and throughout the all but the far
north portion of the Gulf of California. Seas inside the Gulf 
are 3-6 ft and 8 to 13 ft in strong NW swell across the offshore
waters. Moderate N winds and 5-7 ft seas prevail offshore Cabo 
Corrientes to offshore the Mexican state of Guerrero. Northerly 
gap winds to near 30 kt continue across the Gulf of Tehuantepec 
region, where seas are 7-9 ft. 

Fresh NW to N winds will continue through Thu morning on both 
sides of Baja California. A period of fresh to strong NW to N 
winds is expected west of Baja California Norte Thu night. 
Similar winds are forecast in the northern Gulf of California Fri
night into Sat. Large NW swell will peak in size across the Baja
offshore waters overnight as it continues to propagate 
southward, and slowly subside to 8-11 ft on Thu. In the Gulf of 
Tehuantepec, the current strong gap wind event is expected to 
prevail through tonight before diminishing significantly in 
strength and areal coverage Thu. Winds are expected to diminish 
and remain confined to the Gulf of Tehuantepec Thu and Thu night 
before shutting down Fri.

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

Fresh to strong E winds prevail across the Papagayo region, and 
are expected to pulse to strong again Thu and Fri nights before
diminishing. Seas will generally persist at 5-6 ft. Gentle to 
moderate northerly winds and seas 3 to 4 ft in the Gulf of Panama
are forecast to pulse again tonight. Moderate S to SW winds are 
south of the monsoon trough with seas of 5-6 ft in SW swell. 
Light to gentle variable winds are elsewhere. These conditions 
are forecast to remain through the upcoming weekend.

REMAINDER OF THE AREA...

A high pressure ridge continues to settle across the northern 
waters tonight, extends WNW to ESE along 33N to 30N to offshore
of Cabo Corrientes. Large NW swell continues over the Pacific 
waters. Seas of 9 to 14 ft prevail across the water N of 08N and
W of 112W, with highest seas between 120W and 130W. The swell 
will gradually subside as it moves southward, but seas of 12 ft 
will reach as far south as 09N latitude tonight into early Thu 
then gradually subside across the regional waters through Fri.

Fresh NE trade winds prevail across most of the waters S of 24N 
and W of 120W tonight, and will become the zone of highest seas 
overnight through Thu as the peak swell moves through this area.
Two surface trough are analyzed along the ITCZ, along 112W and
along 126W, accompanied by active weather, winds to 25 kt and 
seas 10 to 12 ft. Fresh trades will continue through Sat north 
of the ITCZ to 23N and west of 120W as the ridge prevails.

Looking ahead, a cold front is forecast to move southeast of
30N140W on Sun, with large swell behind it.

$$
Stripling