916 
AXPZ20 KNHC 062151
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Wed Dec 6 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
2130 UTC.

...SPECIAL FEATURE...

Gulf of Tehuantepec Gale Warning: Strong high pressure stretches 
over central Mexico, supporting northerly gale force winds 
across the Gulf of Tehuantepec. Strong winds likely stretch as
far south as 12N. Seas currently range between 7 and 10 ft. This
pattern will persist through Thu. Seas expected to reach as high
as 12 ft tonight into Thu morning. Gale-force winds will end by
Thu evening, with the strong winds diminishing by Fri. Seas will
also subside below 8 ft on Fri.  

Please read the latest 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 the coast of Colombia near 07N78W
to 06N99W to 07N111W. The ITCZ extends from 07N111W to 10N121W
and then from 07N128W to beyond 07N140W. Scattered moderate to
isolated strong convection is noted from 04N to 09N between 133W
and 140W. Scattered moderate convection is noted from 03N to 08N
between 77W and 82W and from 03N to 11N between 87W and 130W.

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

Please read the Special Features section for more information on
the Gale Warning in the Gulf of Tehuantepec.

A broad ridge extends across the offshore waters of Baja 
California from weakening high pressure. The pattern is 
supporting gentle to locally moderate northerly winds across 
most of the Baja California offshore waters. Moderate N to NW 
winds prevail over the southern Gulf of California, including 
the entrance of the Gulf with light to gentle winds in the
northern Gulf. NW swell across the Baja California waters is 
bringing 8 to 11 ft seas mainly over the waters beyond 60 nm of 
the Baja California coastline. Seas range 2 to 4 ft across the 
Gulf of California. Farther south, light to gentle breezes 
persist off southern Mexico with 4 to 6 ft combined seas in mixed
swell.

For the forecast, outside of the gap winds in the Gulf of 
Tehuantepec, long-period NW swell will persist off Baja 
California and the Revillagigedo Islands through Sat. Seas as 
high as 12 ft could move across the Baja California Norte waters 
later today and into tonight. Reinforcing NW swell will arrive 
off Baja California Norte by Thu night into Fri, accompanying a 
decaying cold front moving into the region. Swells will subside 
later in the weekend. Strong winds could develop across most of 
the Gulf of California this weekend, producing rough seas.
Another strong gale-force wind event could occur over the Gulf 
of Tehuantepec late this weekend into early next week with very 
rough seas.

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

Fresh to strong NE to E winds prevail across the Gulf of 
Papagayo, where seas are near 5 to 7 ft. Gentle to moderate 
winds elsewhere over the region. Seas range 5 to 7 ft in the 
Guatemala and El Salvador offshore waters mostly within N to NW 
swell due to the influence of the Gulf of Tehuantepec gap wind 
event. Elsewhere, seas range 3 to 5 ft seas primarily in S to SW
swell. Scattered showers and thunderstorms are noted south of 
the monsoon trough off the coast of Colombia. 

For the forecast, high pressure north of the region will support
pulsing strong winds across the Gulf of Papagayo at night 
through the weekend. Seas could reach 8 ft downwind of the event.
Seas will build well offshore of Guatemala tonight into Thu due 
to swell generated by gale- force gap winds in the Gulf of 
Tehuantepec. Gentle to moderate winds are forecast elsewhere. 
Moderate combined seas will persist through the weekend in a mix
of SW and NW swell.

...REMAINDER OF THE AREA...

High pressure dominates the waters north of 20N. Fresh to locally 
strong trade winds persist south of the ridge, mainly 07N to 23N
west of 110W. Seas in this region are 8 to 13 ft, in a mix of 
seas due to the trade wind flow, and long-period NW swell. A cold
front stretches in the NW corner of the basin from 30N130W to 
26N140W with scatterometer data depicting moderate to fresh N to
NE winds behind the front. A large reinforcing NW swell is 
bringing 10 to 14 ft seas N of 12N and W of 120W. Combined seas 
of 8 to 10 ft cover much of the region elsewhere W of 115W, 
although with primarily S to SE swell S of 04N. Gentle to 
moderate winds and 4 to 7 ft seas are noted east of 110W. A 
surface trough is analyzed along 124W from 08N to 12N with 
scattered moderate convection near them.

For the forecast, the cold front will continue to move across the
waters tonight before decaying by Thu while weakening the high
pressure. This will allow for trade winds to diminish slightly W
of 115W today into tonight. Large, long- period NW swell 
accompanying the front will continue to move across the waters N 
of 10N and W of 120W through tonight supporting seas to 14 ft 
N of 20N and W of 130W. E of 115W, the combination of the NW 
swell with shorter- period NE swell emerging from gap wind events
and fresh E trade winds will support rough seas from 07N to 12N 
between 95W and 110W from Thu into Fri. This swell event will
begin to subside by the weekend and into early next week. 

$$
AReinhart