AXPZ20 KNHC 160346
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Sat Oct 16 2021
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: High pressure will build
across the Gulf of Mexico as a cold front pushes across the
basin. This will bring fresh to strong northerly winds beginning
16/1200 UTC across the Gulf of Tehuantepec. Winds will increase
to gale force by Sun at 0000 UTC and continue through 18/1200 UTC.
Seas are expected to build to 8 to 11 ft downwind of the gale
force winds. Please see the latest High Seas Forecast at
http://nhc.noaa.gov/text/MIAHSFEP2.shtml for more details.
A tropical wave is along 91W and N of 02N, moving W at 10 to 15
kt. Scattered showers are noted from 08N to 12N between 89W and
Another tropical wave extends its axis along 108W from 02N to
17N, moving W at around 10 to 15 kt. Scattered moderate
convection is noted from 06N to 11N between 107W and 112W.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough extends from the coast of Nicaragua near
12N87W to 13N95W to 12N104W to 12N115W to 15N126W to 12N140W.
Aside from the convection associated with the tropical waves
discussed in the section above, scattered moderate convection is
noted from 05N to 13N and E of 112W and from 08N to 16N and W of
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
See the Special Features section for more information on the
gale warning in the Gulf of Tehuantepec.
Earlier scatterometer data depicted fresh northerly winds over
the northern half of the Gulf of California. Light to gentle NW
winds prevail elsewhere along the Mexican coast. Seas average
between 4 to 6 ft across the Mexico offshores, with seas 3 to 4
ft occurring in the Gulf of California. Isolated thunderstorms
are moving southward across the Gulf of Tehuantepec.
For the forecast, fresh to strong northerly winds over the
northern Gulf of California will continue through Sat afternoon.
High pressure will build south across the western Gulf of Mexico
in the wake of a cold front Sat night into Sun. This will bring
strong to near gale force gap winds funneling into the Gulf of
Tehuantepec early Sat morning and pulse to gale force Sat night
through Sun night. Gentle winds are expected to prevail elsewhere
through early next week.
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL
AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR...
Light N winds prevail N of the monsoon trough with gentle to
moderate SW winds ongoing to the S. Scattered thunderstorms are
moving off the coasts of Honduras and El Salvador. Farther
south, scattered thunderstorms are also noted across the coasts
of Costa Rica and Panama. Seas are 4 to 7 ft due to a moderate
For the forecast, light to gentle winds will continue to prevail
N of the monsoon trough with moderate SW winds to the S of the
monsoon trough through the weekend. Seas will average 4 to 6 ft
in SW swell. Fresh to locally strong winds are expected to pulse
in the Gulf of Papagayo Sun night. Scattered thunderstorms are
expected to continue across the region through Sun night.
REMAINDER OF THE AREA...
Moderate to locally fresh NE winds prevail over areas N of the
monsoon trough and W of 120W, with gentle to moderate winds south
of the monsoon trough. Seas are 8 to 9 ft and conditions in this
area will gradually improve through tonight. Swell from a
weakening frontal trough will continue bringing 8 to 9 ft seas
through tonight near the area N of 27N between 125W and 135W. An
area of 8 to 9 ft swell will also develop from 04N to 07N between
109W and 116W tonight and continue through Sat night. Elsewhere,
moderate winds and seas in the 5 to 7 ft range will prevail.