000
AXPZ20 KNHC 162138
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Fri Sep 16 2022

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
2100 UTC.

...SPECIAL FEATURES...

Tropical Storm Lester is centered near 14.3N 97.3W or 400 km SE
of Acapulco, Mexico at 16/2100 UTC moving NW at 10 kt. Estimated
minimum central pressure is 1005 mb. Maximum sustained wind 
speed is 35 kt with gusts to 45 kt. Numerous moderate to strong
convection is within 120 nm SW semicircle. A cluster of moderate
to isolated strong convection is from 15N to 16N between 99W and
101W. Similar convective activity is also noted N of 14.5N 
between 94W and 96W, including the Gulf of Tehuantepec. On the 
forecast track, the center of the cyclone is expected to move 
near or over the coast of southwestern Mexico Saturday or Saturday
night, and dissipate over southwestern Mexico on Sunday morning.
Gradual strengthening is forecast through Saturday morning. Rapid 
weakening is expected after the center crosses the coast of
Mexico. Heavy rains are expected to begin tonight. These rains may 
produce flash and urban flooding, along with possible mudslides 
in areas of higher coastal terrain. Swells generated by Lester are 
affecting portions of the coast of southern Mexico and this will
continue into the weekend. These swells are likely to cause 
life-threatening surf and rip current conditions. Please consult 
products from your local weather office.

Please read the latest HIGH SEAS FORECAST issued by the National
Hurricane Center at website
https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest 
T.D. Thirteen-E NHC Forecast/Advisory and Public Advisory at 
www.hurricanes.gov for more details.

Southwest of Southwestern Mexico:
An area of low pressure located near 14.5N107W or a few hundred 
miles southwest of Manzanillo, Mexico, continues to produce 
disorganized showers and thunderstorms. Environmental conditions 
are forecast to become more conducive for development, and a 
tropical depression is likely to form within the next couple of 
days. This disturbance is forecast to meander off the 
southwestern coast of Mexico through the end of this week, and 
then begin to move northwestward early next week. Numerous 
moderate to isolated strong convection is within 120 nm W 
semicircle. Scattered moderate to isolated strong convection is 
elsewhere from 12N to 16N between 102W and 112W. A broad area of 
fresh to strong SW-W winds is S of the monsoon trough in the 
vicinity of the low center, covering the waters from 08N to 14N 
between 102W and 112W. Seas of 8-11 ft in long period S to SW 
swell are occurring across this area. The latest Tropical Weather
Outlook gives this system a high chance of tropical cyclone 
formation within the next 48 hours.

Refer to the latest NHC Tropical Weather Outlook at 
www.hurricanes.gov for more details on both areas.

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

The monsoon trough extends from 10N84W to 13N94W, then resumes W
of T.S. Lester from near 14N102W to 1006 mb low pres situated 
near 14.5N107W to 11N122W to another 1012 mb low pres located 
near 12N136W to 08N140W. Aside for the convection associated 
with Lester and the low pressure, scattered moderate to strong 
convection is noted from 04N to 07N E of 81W to the coast of 
Colombia. Scattered moderate to isolated strong convection is 
from 09N to 12N between 88W and 91W.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Refer to the Special Features section for details on T.S. Lester
and a low pressure area located a few hundred miles southwest of
Manzanillo, Mexico.

A ridge dominates the offshore of Baja California producing moderate
to locally fresh NW to N winds N of Cabo San Lazaro, and gentle
to moderate NW winds between Cabo San Lazaro and Los Cabos. Seas
are generally in the 4-6 ft range. Light to gentle winds and 
seas of 1-3 ft prevail in the Gulf of California. Marine 
conditions S of Cabo Corrientes are related to T.S. Lester and 
the above mentioned low pressure area with a high chance of 
tropical cyclone formation.

For the forecast, Lester will move to 15.1N 98.4W Sat morning, 
16.6N 99.9W Sat afternoon, move inland and weaken to a tropical 
depression near 18.1N 101.4W Sun morning, and dissipate Sun 
afternoon. A Tropical Storm Warning remains in effect across the
offshore waters from Oaxaca to Michoacan. A ridge will remain in
place across the offshore waters of Baja California through the
upcoming weekend and maintain moderate to fresh winds. Gentle to
occasionally moderate mainly southerly winds and 1-3 ft seas are
expected in the Gulf of California. Marine conditions could begin
to deteriorate between Los Cabos and Cabo Corrientes on Sun, as
the low pressure currently located a few hundred miles southwest of
Manzanillo, Mexico moves northward.

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

Moderate to fresh W-SW winds prevail south of the monsoon 
trough, while light and variable winds are north of the trough 
from the Gulf of Papagayo region to Guatemala coastal waters. 
Seas are 5-7 ft in SW swell across the offshore waters, with the 
exception of 7-9 ft between Ecuador and the Galapagos Islands. 
A moist and unstable environment interacting with the monsoon 
trough persists across the area, mainly N of 05N, resulting in 
active showers and thunderstorms.

For the forecast, mainly gentle to moderate winds will persist
across the offshore forecast waters, with seas of 6-9 ft in SW
swell. Winds could increase to moderate to fresh between northern
Costa Rica and Guatemala toward the upcoming weekend as a broad
area of low pressure develops along the monsoon trough. A very 
moist and unstable atmospheric environment will help maintain 
active weather across most of the offshore waters over the next 
few days. 

REMAINDER OF THE AREA...

Refer to the Special Features section for details on T.S. Lester
and a low pressure area located a few hundred miles southwest of
Manzanillo, Mexico.

High pressure dominates the waters north of the monsoon trough 
and west of about 120W, centered on a 1023 mb high near 29N134W.
The pressure gradient between this system and a 1012 mb low
pressure located near 12N136W supports and area of fresh NW winds
from 12N to 16N between 134W and 138W based on latest satellite
derived wind data. Seas are 7-8 ft within these winds. Gentle to
moderate winds prevail elsewhere north of the monsoon trough. 
Moderate to locally fresh southerly winds are south of the 
monsoon trough along with 5-8 ft seas, outside of T.S. Lester and
a low pressure area located a few hundred miles southwest of 
Manzanillo, Mexico. A broad area of fresh to strong SW-W winds 
prevail S of these tropical systems.

For the forecast, high pressure will continue to dominate the
northern forecast waters. A weak cold front is forecast to enter
the discussion area on Sun, extending roughly from 30N125W to
27N135W to 28N140W by Sun night. Seas of 8-9 ft in northerly
swell will follow the front reaching the waters N of 28N and W 
of 125W by Mon morning. An area of fresh Ne winds with seas to 8 
ft will move westward in tandem with the low pressure located 
near 12N136W. Additional pulses of cross-equatorial SW swell will
continue to propagate across the forecast waters east of 130W. 
Weather conditions will continue to deteriorate across the 
offshore waters from Oaxaca to Michoacan due to the approach of 
Lester.

$$
GR