AXPZ20 KNHC 280908
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Thu Jan 28 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: Strong northerly gap winds
associated with high pressure building across southern Mexico in
the wake of a cold front are funneling through the Chivela Pass,
with gale-force winds occurring in the Gulf of Tehuantepec. Winds
will reach strong gale-force this morning and then again tonight.
This event will generate very large seas, which will peak around
20 ft tonight and Fri. Seas generated from this gap wind event
will propagate well away from the source region, with seas
greater than 8 ft spreading as far west as 110W by Fri night.
Gale-force winds are forecast to persist through early Sat
morning. Looking ahead, another gale-force gap wind event is
possible Sun night into early next week. Please see the latest
High Seas Forecast at http://nhc.noaa.gov/text/MIAHSFEP2.shtml
for more details.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough extends from 07N78W to 05N88W to 06N106W. The
ITCZ extends from 06N113W to 04N128W to beyond 05N140W.
Scattered moderate isolated strong convection is noted from 06N
to 10N between 109W and 113W, and within 60 nm of the ITCZ W of
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
Please see the Special Features section for details on a Gale
Warning for the Gulf of Tehuantepec region.
Moderate north to northwest winds prevail across the Gulf of
California. Light to gentle winds prevail elsewhere. NW swell is
producing 8 to 9 ft seas west of the Baja California peninsula
southward to offshore Cabo Corrientes, with seas in the 4-7 ft
range elsewhere over the open waters off Mexico.
A weakening cold front approaching Baja California Norte tonight
will usher in another set of large NW swell that will spread
southward west of the Baja California peninsula through Sat
morning. This swell will subside this weekend. Another set of NW
swell will reach the waters off Baja California Norte Mon night.
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and
WITHIN 750 NM OF ECUADOR...
Scatterometer data shows moderate winds across the Gulf of
Papagayo, with light to gentle winds elsewhere. Seas are in the
5-7 ft range in Gulf of Papagayo, and 3-5 ft elsewhere.
The offshore winds across the Papagayo region will become fresh
to strong through Sat night. Winds in the Gulf of Panama will
become fresh to strong tonight through Fri night. Gentle to
moderate winds are expected elsewhere. Large seas generated by
strong winds in the Tehuantepec region will spread into the
offshore waters of Guatemala and El Salvador tonight through
REMAINDER OF THE AREA...
A cold front extends across the northwest part of the discussion
area from 30N126W to 25N140W. Scatterometer data shows fresh to
strong winds on either side of the front, and seas are 16-19 ft.
Large NW swell associated with the front will spread south-
southeastward across the forecast region through Fri night. The
gradient between weak high pressure analyzed near 25N120W and
lower pressures near the ITCZ is supporting moderate to fresh NE
trade winds north of the ITCZ to 20N, west of 120W. Seas in this
area are in the 8 to 9 ft range in a mix of NW swell and NE to E
wind waves. The pressure gradient will weaken further today as
the area of high pressure weakens and shifts east. Trade winds
will increase Friday as high pressure builds north of the area
behind the cold front. Another set of NW swell will propagate
into the NW waters on Sunday.