000
AXPZ20 KNHC 132024
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 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 1800 UTC surface analysis and satellite imagery through
2010 UTC.

...TROPICAL WAVES...

The axis of a tropical wave is near 89W north of 05N, moving 
west at around 10 kt. Associated convection is described in the 
section below.

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

The monsoon trough extends from the coast of Panama near 08N80W
to 1010 mb low pressure near 17N103W to 1013 mb low pressure near
13N120W to 09N125W. The ITCZ continues from 09N125W to 08N140W. 
Scattered moderate and isolated strong convection is noted within
300 nm southwest of the monsoon trough between 80W and 101W, and
from 12N to 20N between 101W and 111W.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Showers and thunderstorms remain disorganized in association with
an elongated trough of low pressure located about 100 nm 
offshore the southern and southwestern coasts of Mexico. Moderate
to fresh E-SE winds are funneling up along the coast of 
southwestern Mexico north of the area of elongated low pressure. 
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, environmental conditions are only marginally 
conducive for any slow development over the next couple of days
of the area of elongated low pressure while it moves westward or
west-northwestward at 5 to 10 kt. Regardless of development, 
this system will likely produce heavy rains across portions of 
southern and southwestern Mexico through Tue. Rough seas 
will impact southern Mexico through mid-week due to large SW 
swell moving across the region. Seas will reach 8 ft off Baja 
California through mid-week 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 continue to impact the 
region subsiding by the end of the week, along with gentle to 
moderate winds.

REMAINDER OF THE AREA...

A broad swath of fresh to locally strong SW winds prevail within
300 nm south of the monsoon trough east of 110W. 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 07N to 14N between 100W 
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 24N 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