000
AXPZ20 KNHC 122035
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Sun Sep 12 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 1800 UTC surface analysis and satellite imagery through
2030 UTC.

...SPECIAL FEATURES...

1010 mb low pressure is centered along the Oaxaca close to 
Puerto Angel. A recent scatterometer satellite pass indicated 
strong to near gale force winds southerly winds off the coast of
Chiapas and eastern Oaxaca. The low will move onshore this 
afternoon and early this evening and further development is 
unlikely. However, broad low pressure may persist off Guerrero 
and Michoacan through mid week, before moving between Cabo 
Corrientes and Socorro Island by Fri, and there is a medium 
chance a tropical depression may form through mid week. 
Regardless of development, this system will likely produce heavy 
rains across portions of southern Mexico through Tue. Please see 
the latest eastern north Pacific Tropical Weather Outlook for 
more information.

...TROPICAL WAVES...

The axis of a tropical wave is near 85W north of 02N, moving 
west at 10-15 kt. No significant convection is observed near this
tropical wave.

The axis of a tropical wave is near 98W/99W, moving west at 10 
kt. Scattered moderate to isolated strong convection is noted 
from 12N to 16N between 95W and 101W. Low pressure near the 
tropical wave will be monitored for the potential for tropical 
cyclogenesis. Please see Special Features section above for more 
information.

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

The monsoon trough extends from 11N86W to 1010 mb low pressure 
near 15N97W to 08N125W to 10N140W. No significant convection is
noted along the monsoon trough, aside from convection noted in 
the tropical waves section above.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Please see the Special Features section above for details on
the developing area of low pressure with the potential for 
developing into a tropical cyclone.

In addition to strong to near-gale force winds off Chiapas and
Oaxaca, a recent altimeter satellite pass confirms seas of 8 to
12 ft in the waters off southern Mexico, due mostly to long-
period SW swell propagating into the region. Farther north, a
scatterometer satellite pass detected gentle to moderate winds
around the remnant low of Olaf near 24N115W, or about 210 nm 
west- southwest of Cabo San Lazaro in Baja California Sur.

For the forecast, in addition to the potential for development of
low pressure along the coast of Mexico, the main issue will be
the SW swell moving into the region through mid week. Seas may
reach 8 ft off Baja California through Mon night in a mix of NW
and S swell. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, 
COLOMBIA, and WITHIN 750 NM OF ECUADOR...

Fresh SW winds prevail over the offshore waters of Guatemala and
El Salvador, along with 6 to 9 ft seas in SW swell. Farther 
south, gentle to moderate southerly winds persist off Colombia 
and Ecuador, with seas of 6 to 8 ft in SW swell.

For the forecast, large SW swell will impact region into early 
next week, along with moderate winds. Looking ahead, seas
will subside through the latter part of the week across the
region.

REMAINDER OF THE AREA...

Recent scatterometer satellite passes showed a broad swath of
fresh SW winds within 360 nm south of the monsoon trough east of
115W. Concurrent altimeter satellite passes showed seas in 
excess of 8 ft across much of the area south of 15N and east of
120W, with maximum seas of 12 to 13 ft near from 06N to 13N
between 95W and 105W mainly due to local wind flow and persistent
cross-equatorial southerly swell. Gentle to moderate winds and 
moderate seas are noted elsewhere. Winds and seas will diminish
across the region through mid week.

$$
Christensen