000
AXPZ20 KNHC 131511
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Mon Sep 13 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 1200 UTC surface analysis and satellite imagery through
1440 UTC.

...SPECIAL FEATURES...

Showers and thunderstorms have increased overnight in association 
with an elongated 1009 mb area of low pressure located more than
100 nm southwest of Acapulco, Mexico near 16N101W. Scattered 
moderate and isolated strong convection is noted within 180 to 
240 nm of the coast of Mexico between 99W and 106W. Associated
winds are currently around 20 to 25 kt with seas of 8 to 11 ft. 
Environmental conditions are marginally conducive for 
development, and a tropical depression could form during the next
couple of days while it moves westward or west-northwestward 
just offshore of the coast of southern Mexico. Regardless of 
development, this system will likely produce heavy rains across 
portions of southern and southwestern Mexico through Tue. There 
is a medium chance that this system will develop into a tropical 
cyclone. Please see the latest eastern north Pacific Tropical 
Weather Outlook at www.hurricanes.gov for more information.

...TROPICAL WAVES...

The axis of a tropical wave is near 88W north of 05N, moving 
west at 10 to 15 kt. Associated convection is described in the
section below.

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

The monsoon trough extends from the coast of Colombia near 09N76W
to the coast of Costa Rica near 10N86W to low pressure near 
16N101W to low pressure near 12.5N120W to 09N128W. The ITCZ 
continues from 09N128W to 09N140W. Scattered moderate and 
isolated strong convection is noted within 300 nm south-southwest
of the monsoon trough between 76W and 97W. Scattered moderate
convection is noted from 07N to 12N between 105W and 117W.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

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

Fresh to strong SW winds prevail south of southern Mexico. Gentle
to moderate winds are noted west of Baja California Norte. Light
to gentle winds are elsewhere. A large area of SW swell is
impacting the waters off southern Mexico, with seas in the 8 to 12
ft range. Seas are in the 7 to 8 ft range over the remainder of 
the open waters off Mexico in a mix of SW and northerly swell. 
Over the Gulf of California, seas are 3 ft or less. 

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 across the region through mid week. The SW 
swell will cause rough seas off southern Mexico with the 
potential for hazardous surf along the coast through the early 
part of the week. Seas will reach 8 ft off Baja California 
through midweek in a mix of NW and S swell. 

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

Gentle to moderate prevail over the offshore waters along with 6
to 10 ft seas in SW swell. 

For the forecast, large SW swell will impact region through mid-
week, along with gentle to moderate winds. Seas will subside 
through the latter part of the week across the region. 

REMAINDER OF THE AREA...

A broad swath of fresh to locally strong SW winds prevail within
360 nm south of the monsoon trough east of 115W. Seas are in 
excess of 8 ft across much of the area south of 15N and east of 
122W, with maximum seas of 12 ft from 06N to 13N between 95W and
110W, mainly due to local wind flow and persistent cross- 
equatorial southerly swell. NW to N swell is supporting seas of 7
to 9 ft north of 23N between 120W and 130W. Gentle to moderate 
winds and moderate seas are noted elsewhere.


For the forecast, winds and seas will diminish across the region
through mid week.

$$
Lewitsky