000
AXPZ20 KNHC 121541
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Tue Jan 12 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
meteorological analysis.

Based on 1200 UTC surface analysis and satellite imagery through
1500 UTC.

...SPECIAL FEATURES...

Gulf of Tehuantepec Gale Warning: Northerly winds behind a cold 
front moving across the Gulf of Mexico continue to funnel through
the Chivela pass into the Gulf of Tehuantepec. Gale conditions, 
with winds in the 35 to 40 kt range, are forecast to continue 
through Thu. Large seas generated from this gap wind event will 
spread well downwind and away from the Tehuantepec area, with 
seas greater than 12 ft reaching as far as 10N100W tonight. Winds
are forecast to diminish below gale force Thu. 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 from 10N74W to 06N85W to 09N112W to
08N122W. The ITCZ continues from 08N122W to 07N140W. Scattered 
moderate isolated strong convection is noted from 07N to 13N 
between 103W and 117W. Scattered moderate convection from 05N to
07N E of 80W.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Gale force winds prevail across the Tehuantepec region. Please 
see Special Features section for more details.

Elsewhere, mainly gentle to moderate NW to N winds are expected 
across the offshore waters of Baja California over the next 
several days as a ridge remains in place. NW swell continues to
propagate through the waters west of the Baja California
peninsula, with seas of 10-12 ft prevailing. Additional pulses 
of large NW swell will reach this region maintaining seas 8 ft or
greater over this area for much of the week.

Gulf of California: High pressure centered over the Great Basin 
region of United States is supporting fresh to locally strong NW
winds across the central and south parts of the Gulf of California.
with peak seas around 6 ft. These winds will persist on Wed.

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

Fresh offshore gap winds across the Gulf of Papagayo region will
pulse to strong at night through the middle of the week. Seas
will build to 9 or 10 ft during this time. Outside of the gap 
winds areas, mainly light to gentle winds will prevail north of 
the monsoon trough while gentle to moderate S to SW winds are 
expected to the south.

Large seas generated in the Tehuantepec region will impact the 
offshore waters of Guatemala and El Salvador tonight through Thu.
Seas will peak 10-13 ft today.

REMAINDER OF THE AREA...

High pressure of 1026 mb is centered near 30N128W. The pressure 
gradient between this area of high pressure and lower pressure in
the vicinity of the ITCZ is supporting fresh to locally strong 
trade winds north of the ITCZ to 20N and W of 120W. Seas in this 
area are in the 10-13 ft range, based on altimeter data, in a 
mix of NW swell and NE-E wind waves. These general marine 
conditions will persist during the next few days.

Long period NW swell continues to propagate across the forecast 
region, with seas 8 ft or greater across the waters west of 
100W. Another pulse of NW swell has entered the NW waters, with 
seas to 16-17 ft near 30N140W. Yet another pulse of NW swell 
will enter the NW waters Thu night, with seas of up to 18-19 ft 
near 30N140W. These successive sets of NW swell will maintain 
seas greater than 8 ft over much of the forecast waters west of 
100W through much of the week.

$$
GR