000
AXPZ20 KNHC 270810
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Wed Oct 27 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 0600 UTC surface analysis and satellite imagery through
0730 UTC.

...TROPICAL WAVES...

A tropical wave axis is analyzed along 102W/103W north of 04N 
into coastal southwestern Mexico, moving W at 10 to 15 kt. No 
significant deep convection is noted.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

The monsoon trough extends from 1010 mb low pressure near 11N75W
to across Costa Rica and the Papagayo region to 11N90W to 10N95W,
then resumes from 14N107W to 1012 mb low pressure near 11N115W to
10N130W to 1012 mb low pressure near 09N140W. Scattered 
moderate and isolated strong convection is noted from 06N to 09N
between 77W and 81W, from 09N to 11N between 92W and 97W, from
10N to 14N between 110W and 117W, from 07N to 10N between 119W
and 124W, and from 07N to 11N between 136W and 140W.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

A cold front is moving across northwestern Mexico near the border
with Texas and New Mexico to across the central Gulf of 
California to across Baja California Sur and southwestward. 
Fresh to strong NW-N winds behind the front have diminished to
fresh early this morning, with moderate to fresh NW-N winds in 
the northern and central Gulf of California. Gentle to moderate 
winds prevail elsewhere. Large NW swell is outrunning the front 
with seas of 8 to 15 ft offshore of Baja California. Seas are 5 
to 8 ft elsewhere over the open waters in mixed swell, with 
mainly 3 to 6 ft seas in the Gulf of California, highest in the
central part.

For the forecast, fresh winds behind a cold front west of Baja 
California will diminish today as the front weakens. Fresh to 
strong winds behind the same boundary will develop in the central
Gulf of California later today as the pressure gradient 
tightens. Large NW swell will continue to propagate across the 
open offshore waters with seas in excess of 12 ft expected west 
of Baja California through tonight. A cold front forecast to move
through the western Gulf of Mexico will bring fresh to strong 
gap winds to the Gulf of Tehuantepec Thu night and continue 
through the upcoming weekend. 

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

Gentle to moderate SW to W winds are occurring south of the 
monsoon trough, with mainly light and variable winds north of the
monsoon trough, locally moderate in the Papagayo region. Seas 
are mainly 4 to 6 ft, except 5 to 7 ft offshore of Ecuador in 
moderate southerly swell. 

For the forecast, mainly gentle to moderate SW winds will 
persist over the offshore waters through the next several days, 
except light and variable winds north of the monsoon trough. A 
moderate southerly swell will prevail through the next several 
days with seas less than 8 ft. 

REMAINDER OF THE AREA...

A weakening cold front extends from Baja California Sur near 
25N112W to 22N120W. Large NW swell is outrunning the front with 
seas of 8 ft or greater covering the majority of the waters north
of 02N and west of 108W, with seas around 15 ft across the
central portion of that area per recent altimeter data. Seas are
5 to 8 ft elsewhere in remnant mixed swell. Mainly moderate to 
fresh NE to E winds prevail across the open waters north of the 
convergence zone, while moderate to fresh S to SE winds prevail 
to the south of the convergence zone.

For the forecast, the front will continue to weaken as it moves
southward and eventually dissipate through tonight. Winds are 
forecast to diminish across the open waters by the end of the 
week as the pressure gradient slackens. The next cold front may 
approach 30N140W Sat night with fresh to strong SW winds ahead of
it into Sun. Meanwhile, the large NW-N swell will continue to 
propagate southward while gradually decaying through the end of 
the week. Another set of NW swell is likely with the next front 
this weekend.

$$
Lewitsky