AXPZ20 KNHC 070256
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Thu Dec 7 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 0000 UTC surface analysis and satellite imagery through
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 8 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 06N109W. The ITCZ extends from 06N109W to 09N120W and then
from 08N127W to beyond 08N140W. Scattered moderate convection is
noted from 05N to 11N and W of 118W.
...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 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
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 6 to 8 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 will 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
strong trade winds persist south of the ridge, mainly 08N to 25N
W of 115W. Seas in this region are 8 to 14 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 30N127W to
26N140W with scatterometer data depicting moderate to fresh N to
NE winds behind the front. Seas to 12 ft are noted along the
front. Combined seas of 8 to 10 ft cover much of the region
elsewhere W of 112W, although with primarily S to SE swell S of
04N. Gentle to moderate winds and 4 to 7 ft seas are noted E of
112W. 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 weakening the high
pressure. This will allow for trade winds to diminish slightly W
of 115W 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 Thu and Fri. This swell event will begin to subside by the
weekend and into early next week.