000
AXPZ20 KNHC 191036
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Thu Dec 19 2024

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
0900 UTC.

...SPECIAL FEATURES...

Gulf of Tehuantepec Gale Warning: 
The passage of a cold front and a high pressure in its wake will
enhance northeasterly winds across the Gulf of Mexico. This is
going to sustain near gale to gale-force gap winds in the Gulf of
Tehuantepec through early Sunday morning. Seas under the
strongest winds will peak between 10 and 12 ft. As the high
shifts eastward, this should allow winds and seas in the Gulf of
Tehuantepec to gradually subside Sunday afternoon and evening. 
Please see the latest NWS High Seas and Offshore Waters Forecasts
issued by the National Hurricane Center at website:
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...

A monsoon trough curves southwestward from the west coast of 
central Costa Rico to 04N94W. An ITCZ continues westward from 
04N94W to 05N122W, then from 05N105W to 05N125W to beyond 140W 
at 06N. Scattered moderate convection is seen south of the 
monsoon trough from 05N to 07N between 77W and 85W. Widely
scattered showers are found near the ITCZ from 05N to 09N
between 120W and 135W.

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

Please read the Special Features section about a Gale Warning at
the Gulf of Tehuantepec.

A surface ridge extending southeastward from a 1024 mb high near
33N127W to near the Revillagigedo Islands is supporting light to
gentle winds and seas of 6 to 8 ft in decaying NW swell across 
the Baja California offshore waters. Gentle to moderate NW winds
with 2 to 4 ft seas are present at the Gulf of California. 
Gentle northerly winds and seas at 4 to 6 ft in mixed moderate 
swell exist at the central and southern Mexico offshore waters, 
except at the Gulf of Tehuantepec. Outside the Gale Warning area,
fresh to strong northerly winds with 6 to to 10 ft are evident 
offshore from Oaxaca State in southern Mexico.

For the forecast, strong to gale-force gap winds and very rough 
seas in the Gulf of Tehuantepec are expected to continue through 
early Sun morning, then gradually subside Sun afternoon and 
evening. Light to gentle winds at the offshore waters west of 
Baja California will increase to between moderate and fresh this 
weekend through early next week. Moderate to fresh NW winds in 
the central Gulf of California will diminish to between gentle 
and moderate by Thu. Moderate NW swell west of Baja California 
will become large late this weekend.

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

A broad surface ridge over the northwestern Caribbean Sea is
causing fresh to strong NE winds and seas of 4 to 7 ft in the 
Gulf of Papagayo region. Moderate northerly winds with seas at 3
to 5 ft exist at the Gulf of Panama. Elsewhere south of the 
monsoon trough and between Ecuador and the Galapagos, gentle to
moderate southerly winds and 4 to 6 ft seas in moderate S to SW 
swell prevail.

For the forecast, fresh to strong NE winds will continue in the 
Papagayo region through this weekend, before decreasing early 
next week. Moderate to fresh northerly winds are expected in the 
Gulf of Panama through Mon. Gentle to moderate winds between 
Ecuador and the Galapagos Islands will continue through Fri, then
mainly gentle afterward. 

...REMAINDER OF THE AREA...

Convergent trades are triggering scattered moderate convection
south of the Revillagigedo Islands from 10N to 13N between 105W
and 113W. Moderate to fresh SW winds and 8 to 10 ft seas are
evident to the east of a cold front northwest of a line from 
30N134W to 26N140W. A surface ridge extending southeastward from 
a 1024 mb high near 33N127W to near the Revillagigedo Islands is 
supporting gentle to moderate northerly winds north of 18N and 
west of 120W. Seas in this area range from 6 to 8 ft in moderate 
to large NW swell. The gradient between this ridge and the ITCZ 
to the south is sustaining moderate to fresh trades with 7 to 9 
ft seas over the tropical waters from the ITCZ to 18N and west of
about 110W. Gentle to moderate trades and seas of 5 to 7 ft in 
mixed moderate swells are found elsewhere south of the ITCZ west 
of 92W.

For the forecast, the southern end of the aforementioned cold 
front will cross 140W later this morning and sustain fresh to
strong winds with 10 to 13 ft seas northwest of a line from
30N132W to 26N140W. As the cold front weakens this evening, both
winds and seas will gradually subside tonight and Fri morning.
Afterward, another cold front will cause a similar episode from
Fri evening through Sat. NW swell related to the second cold
front will cause seas north of ITCZ to rise to between 10 and 18
ft by Sun. NE winds from the ITCZ and 18N, west of 128W are
expected to become fresh to strong by Sun. Little change is
expected elsewhere.

$$

Chan