000
AXPZ20 KNHC 092120
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Thu Jan 9 2025

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: Northerly gap winds in the Gulf
of Tehuantepec have diminished below gale-force this afternoon,
now fresh to strong with residual seas of 8 to 12 ft. Winds will
diminish to 20 kt or less after sunset, while residual seas,
extending down to 07N99W at 8 ft, finally subside early Fri
evening. The improvement in marine conditions will be brief as
another northerly gap wind event is forecast to commence Fri
night as a cold front moves through the Gulf of Mexico with high
pressure surging south across eastern Mexico behind it. Northerly
winds of 20 to 30 kt will return in the Gulf of Tehuantepec late
Fri night, reaching gale-force around sunrise Sat, then
diminishing back below gale-force late Sat night, and to less
than 20 kt by Sun morning. Seas will build to 8 to 11 ft with 
this next event. Looking ahead, another northerly gap wind event 
is possible in the Gulf of Tehuantepec early next week, with
fresh to strong winds returning Mon morning, possibly reaching
gale-force Mon evening, then continuing through at least Tue
night. Seas may build to at least 8 to 12 ft by Tue morning with
those winds.

Please read the latest High Seas and Offshore Waters Forecasts 
issued by the National Hurricane Center at websites:
https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and
www.nhc.noaa.gov/marine/offshores_eastpac.php for more
details.

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

The monsoon trough extends from Costa Rica near 09N84W to 07N95W
to 06N115W to 05N126W. The ITCZ extends from 05N126W to 06N134W
to beyond 03N140W. Widely scattered moderate convection is noted
from 04N to 09N between 77W and 84W, from 06N to 10N between 92W
and 103W, and from 05N to 20N between 103W and 121W.

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

Please refer to the Special Features section for details on a
Gale Warning in effect for the Gulf of Tehuantepec, with Gale
conditions also possible early next week.

High pressure of 1031 mb is located north of the discussion
waters near 35N134W with a ridge extending southeastward to near
the Revillagigedo Islands. The pressure gradient across the
offshore waters of Mexico to the west and northwest of the
Tehunatepec region has weakened, allowing for winds of gentle to
moderate to prevail, locally fresh still near Cabo San Lucas.
Decaying NW swell of 7 to 9 ft is west of Baja California, with
4 to 7 ft seas between there and the Tehuantepec region. In the
Gulf of California, seas are 2 to 4 ft, except 3 ft or less in
the central portion.

For the forecast, aside from the Gale Warning in the Gulf of 
Tehuantepec, pulsing fresh to locally strong NW winds will occur 
in the Gulf of California this evening into Sat as low pressure 
drifts southeastward through central Mexico and troughing 
prevails over Baja California. Similar winds will pulse offshore
Baja California later tonight into Sat. Winds will be mainly
moderate or weaker elsewhere through early next week, except
locally fresh offshore SW and southern Mexico Fri into Sat.
Meanwhile, NW swell of 7 to 9 ft offshore Baja California will
linger through Fri night, decaying Sat. A new set of NW swell may
move into the Baja California Norte waters Sat night through Sun
night before also decaying. Little change in seas is expected
elsewhere.

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

A tight pressure gradient is over the Papagayo region between
high pressure ridging over interior northern Central America and
the monsoon trough over southern Costa Rica. This pattern 
continues to support fresh to near-gale force NE to E winds in 
the Gulf of Papagayo to near 09N88W per a recent ASCAT
scatterometer pass. Seas are 5 to 8 ft with these winds. Gentle 
to moderate winds prevail across the remainder of the offshore 
waters, except moderate to fresh downwind of the Gulf of Panama.
Seas are mainly 3 to 6 ft away from the Papagayo gap wind event,
except locally 6 to 9 ft well offshore western Guatemala due to 
earlier gale-force gap winds in the Gulf of Tehuantepec. Widely
scattered showers and thunderstorms are offshore Panama and 
Colombia.

For the forecast, fresh to strong NE to E gap winds will occur 
across the Gulf of Papagayo through Fri morning, and locally 
rough seas will accompany the winds. Winds are expected to 
diminish slightly and pulse to fresh speeds thereafter through
Mon before increasing back to fresh to strong by Mon night.
Elsewhere, winds will pulse moderate to fresh speeds in the Gulf
of Panama through at least this weekend, mainly at night. Winds 
will be moderate or weaker across the remainder of the offshore 
waters through at least the next several days. Rough seas 
generated by a diminishing Gulf of Tehuantepec gap wind event
will continue to impact the far western offshore waters of 
Guatemala through tonight, with peak seas to 9 ft possible. 
Slight to moderate seas will prevail elsewhere into early next 
week. 

...REMAINDER OF THE AREA...

High pressure of 1031 mb is located north of the discussion
waters near 35N134W with a ridge extending across the waters
north of the monsoon trough and ITCZ. Moderate to fresh trades
prevail from 10N to 24N and west of 115W per recent ASCAT
scatterometer data. Active convection persists across the central
waters as described above due to a persistent mid to upper level
trough, leading to locally higher winds and seas. Winds are 
moderate or weaker across the remainder of the open waters, 
including south of the monsoon trough and ITCZ. Seas are 7 to 10 
ft in NW swell north of 06N and west of 110W, and 5 to 7 ft 
elsewhere.

For the forecast, high pressure will prevail north of the monsoon
trough and ITCZ through the upcoming weekend, supporting mainly 
moderate to locally fresh trades across the waters north of the 
monsoon trough and ITCZ. Trades are forecast to briefly increase
to fresh to strong tonight from 12N to 22N west of 130W as the
pressure gradient tightens there. NW swell will continue to
support seas of 7 to 10 ft across the majority of the waters 
north of 08N and west of 110W through Sat. A set of slightly
larger and more northerly swell is forecast to push south of 30N
Sat night through Sun night, with seas building to around 12 ft
near 30N between 120W and 130W. Winds and seas are forecast to
diminish and subside somewhat early next week as the pressure
gradient across the waters north of the monsoon trough and ITCZ
relaxes. Meanwhile, active convection is expected to continue 
across the central tropical Pacific through the remainder of the 
week due to a vigorous upper level trough moving through the 
region. 

$$
Lewitsky