AXPZ20 KNHC 180943
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Mon Jan 18 2021
Tropical Weather Discussion for the eastern Pacific Ocean from
the Equator to 32N, east of 140W. The following information is
based on satellite imagery, weather observations, radar, and
Based on 0600 UTC surface analysis and satellite imagery through
Gulf of Tehuantepec Gale Warning: A locally tight pressure
gradient across the Tehuantepec region will continue to bring
gale- force northerly winds with 12 ft seas through this
morning. Expect pulsing fresh to strong winds thereafter through
early Fri with seas 8 to 10 ft. Please read the latest NWS High
Seas Forecast issued by the National Hurricane Center at website
https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough extends off the coast of Costa Rica near
08N84W to 05N100W to a 1010 mb low near 08N118W. The ITCZ begins
near 08N123W to 08N133W to 06N140W. Scattered moderate to
isolated strong convection is noted from 06N to 10N between 122W
and 134W. Scattered moderate convection is from 04N to 10N
between 95W to 118W.
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
There is a gale warning in effect for the Tehuantepec region.
Please see Special Features section for more details.
Gentle to moderate NW to N winds will prevail across the offshore
waters of Baja California and SW Mexico through this evening as
a ridge remains NW of the area. Sets of NW swell west of Baja
California will impact the offshore waters through midweek. A
1012 mb low pressure area NW of Punta Eugenia near 29N119W will
continue deepen as it meanders west of Baja California Norte
through Wed and weaken by Wed night. Fresh to strong winds and
building seas are expected near the low Tue through Wed.
Gulf of California: Light to gentle winds prevail. By Tue, as
the surface low begins to deepen NW of Punta Eugenia, moderate to
fresh southerly winds will develop in the region. Winds will
become fresh to possibly locally strong Tue evening through Wed
morning. Gentle to moderate winds will return Thu.
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and
WITHIN 750 NM OF ECUADOR...
Fresh to strong winds will pulse in the Papagayo region through
early Fri. Moderate to fresh winds will pulse in the Gulf of
Panama through early Thu. Mainly gentle to moderate winds are
forecast elsewhere. Seas will build slightly from west to east in
mixed long period S and NW swell Wed night through early Fri.
REMAINDER OF THE AREA...
High pressure north of the area extends a ridge into the
northwest forecast waters. The pressure gradient between the
ridge and lower pressures near the convergence zone is supporting
moderate to fresh trade winds north of the convergence zone to
near 20N west of 110W. Seas in this area are in the 7-10 ft
range in a mix of NW swell and NE to E wind waves through
The low pressure offshore of Baja California Norte will support
an area of fresh to strong northerly winds on the western side of
the low, N of 25N between 120W and 131W, Mon evening through
Wed. Seas will build to 14 ft through Wed.
A large NW swell continues moving south and east of 30N140W with
seas up to 14 ft near 29N138W. NW swell will maintain seas
greater than 8 ft over much of the forecast waters west of 100W
through Tue night. The swell will subside south of 20N and west
of 115W by Thu, while fresh northerly swell develops north of
20N in association with the deepening area of low pressure. Seas
will subside throughout the open waters by the end of the week,
with the next potential northerly swell event arriving by the