AXPZ20 KNHC 042212
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Mon Dec 4 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
Gulf of Tehuantepec Gale Warning: Strong high pressure continues
to build over central Mexico. This is supporting a surge of
northerly gap winds reaching gale force across the Gulf of
Tehuantepec. This pattern will persist through much of week,
with gales pulsing mainly at night through Thu night. Seas may
reach 10 to 12 ft downstream of the strongest winds during the
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 off the coast of Panama/Colombia
border near 07N78W to 06N97W. The ITCZ extends from 06N97W to
07N107W and then from 07N113W to beyond 10N140W. Scattered
moderate convection is noted from 04N to 09N between 89W and
105W and from 04N to 11N between 112W and 140W.
...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 1026 mb high pressure near 31N129W to the
Revillagigedo Islands. The pressure gradient between the ridge
and a trough located along the eastern shore of the Gulf of
California supports fresh to locally strong NW to N winds over
the central and southern Gulf of California. Seas range 4 to 6
ft in this area. The pattern is also supporting mainly moderate
NW to N winds off Baja California. NW swell has moved across the
Baja California Norte waters bringing 8 to 10 ft seas N of 23N.
South of 23N, seas are 6 to 8 ft in NW swell. Farther south,
light breezes persist off southern Mexico, with 4 to 7 ft
combined seas in mixed swell. Scattered thunderstorms are
occurring across the Michoacan and Jalisco offshore waters.
For the forecast, outside of the gap wind event in the Gulf of
Tehuantepec, long- period NW swell will persist off Baja
California and the Revillagigedo Islands through most of the
week. Seas as high as 12 ft could move across the California
Norte waters by Wed night. Reinforcing NW swell will arrive off
Baja California Norte by Thu night into Fri, accompanying a cold
front moving into the region.
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA,
AND WITHIN 750 NM OF ECUADOR...
Fresh to strong NE to E winds are prevailing across the Gulf of
Papagayo. Seas are 5 to 6 ft in this area. Gentle to moderate
winds are noted elsewhere, with 4 to 6 ft seas primarily in SW
swell. Scattered thunderstorms are noted south of the monsoon
trough off the coast of Colombia.
For the forecast, high pressure building north of the region
will support pulsing strong winds across the Gulf of Papagayo
particularly at night. Seas will build well offshore of
Guatemala by Wed due to swell generated by gale- force gap winds
in the nearby Gulf of Tehuantepec. Gentle to moderate winds are
forecast elsewhere. Moderate combined seas will persist through
mid week in a mix of SW and NW swell.
...REMAINDER OF THE AREA...
High pressure dominates the waters north of 18N. Fresh to strong
trade winds are noted south of the ridge, mainly from 10N to 27N
west of 110W. Seas in this region are 9 to 12 ft, in a mix of
locally seas due to the trade wind flow, and longer-period NW
swell. Combined seas of 7 to 10 ft cover much of the region
elsewhere west of 110W, although with primarily S to SE swell
south of 10N. Gentle to moderate winds and 5 to 7 ft seas are
noted east of 110W. A trough extends across the waters from
16N109W to 08N111W with scattered moderate convection around it
from 08N to 16N between 109W and 112W.
For the forecast, the high pressure will dissipate by Tue into
Wed as a cold front moves eastward across the waters north of
25N Tue through Thu. This will allow trade winds to diminish
slightly west of 110W through mid week. Large, long- period NW
swell accompanying the front will move across the waters north
of 10N and west of 120W through mid week. This swell will bring
seas as high as 16 ft N of 25N and W of 130W on Tue. In waters
east of 110W, 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.