000
AXPZ20 KNHC 140844
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Tue Dec 14 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
0800 UTC.

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

The monsoon trough extends from 09.5N74W to 09.5N84W to 06.5N100W.
The ITCZ extends from 06.5N100W to 07.5N112W to beyond 08N140W. 
Scattered moderate convection is within 180 nm S of the trough
between 82W and 99W. Scattered moderate isolated strong 
convection is from 09N to 14.5N between 102W and 111W, and 
from 18N to 21N between 127W and 130.5W.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO

High pressure over the northern Gulf of Mexico continues to 
support northerly wind flow across the Isthmus of Tehuantepec, 
resulting in strong northerly gap winds to 30 kt across the Gulf 
of Tehuantepec. Fresh winds to 20 kt extend downwind to near 
13.5N96.5W. Seas across this area are 8 to 10 ft. This strong gap
wind flow is expected to prevail through Wed night before 
diminishing significantly in strength and areal coverage. Winds 
are expected to diminish to fresh to strong and remain confined 
to the Gulf of Tehuantepec Thu through Friday morning before 
shutting down.

A 1022 mb high pressure center has shifted eastward to the outer
offshore waters of Baja California to near 26N118W, and is 
promoting light to gentle winds across most of the rest of the 
Mexican offshore waters. Moderate northerly winds prevail across 
the nearshore waters from southern Sinaloa to the Cabo 
Corrientes area, while fresh S to SW winds have developed across 
the far northern Gulf of California. Seas are 2 to 3 ft in the 
Gulf of California, except 3 to 4 northern portions, and 3 to 5 
ft elsewhere S of 24N.

An approaching cold front has reached along 30N124W tonight, and
will move into the waters W of Baja California Norte Tue. Fresh 
to locally strong SW winds are expected ahead of the front N of 
27N and in the northern Gulf of California Tue night, with a 
brief period of fresh to locally strong NW winds behind it 
through Wed as well. Large NW swell has begun to move into the 
outer NW offshore waters tonight, where seas have built to 8-10 
ft. This swell will move into the remaining N offshore waters 
overnight, with building seas areawide expected through Wed, 
peaking at 10-15 ft N of 24N early Wed morning.

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

Fresh to strong NE to E continue across the Papagayo region with
seas to 7 ft. These gap winds are forecast to continue through 
Wed, and then diminish to moderate to fresh through Fri night. 
Peak seas are forecast to be around 6 ft. Gentle to moderate 
northerly winds and seas 3 to 4 ft in the Gulf of Panama are 
forecast to pulse nightly through Wed night. Moderate S to SW 
winds are south of the monsoon trough with seas to 6 ft in SW 
swell. Light to gentle variable winds are elsewhere. These 
conditions are forecast to remain for much of the week.

REMAINDER OF THE AREA...

High pressure of 1022 mb is along the outer portion of the Baja 
offshore waters near 26N118W. A cold front is moving SE across 
the northern waters and extends from 30N124W to 23.5N140W. This 
front is forecast to continue moving E-SE into mid-week, 
accompanied by very large NW swell. Seas S of 30N are currently 
9-17 ft behind the front. A pair of weakening troughs are to the
south of the front, along 127W and 133W, with the resultant 
pressure gradient producing a zone of moderate to fresh E winds 
from 08-20N between 110W and 130W. Elsewhere mainly gentle to 
moderate NE to E winds are N of 24N with seas to 6-7 ft in NW 
swell. Moderate to fresh E to SE winds are S of the ITCZ W of 
121W with seas 6 to 7 ft. 

Large NW swell will continue to build across the NW waters and 
move east of 120W Tue afternoon. Seas are expected to peak at 
18-19 ft across the far NW waters Tue morning, with seas 
remaining 12 ft and greater N of 17N and W of 120W through Wed
night.

$$
Stripling