000
AXPZ20 KNHC 230320
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Fri Jul 23 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 0000 UTC surface analysis and satellite imagery through
0230 UTC.

...TROPICAL WAVES...

A tropical wave is along 98W, from 04N to 15N, moving west at 5
to 10 kt. Scattered moderate to strong convection is evident from
09N to 14N between 94W and 101W. 

Another tropical wave is near 107W, from 05N to 17N, moving west
around 15 kt. Scattered moderate convection is noted from 06N to
11N between 105W and 113W.

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

The monsoon trough extends from Panama near 08N78W to 07N83W to
09N93W to 1009 mb low pres near 11N122W to beyond 10N140W. In 
addition to the convection listed in the Tropical Waves section,
scattered moderate to strong convection is noted from 05N to 11N
east of 93W. Scattered moderate and isolated strong convection 
is north of the low from 11N to 16N between 120W and 126W. 
Scattered moderate convection is from 08N to 15N between 113W and
119W and from 10N to 15N between 128W and 131W. The monsoon
trough is expected to enhance heavy rain and possible flooding 
over portions of Costa Rica and Panama through this weekend.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Strong northerly gap winds continue in the Gulf of Tehuantepec. 
This is related to high pressure over the Gulf of Mexico and a 
tropical wave that passed through the area earlier on Thursday 
with seas estimated to be 5 to 8 ft in this area. Light to gentle
breezes with 3 to 5 ft seas are evident elsewhere off southern 
Mexico, with a component of SW swell. Farther north, mainly 
moderate NW winds prevail across the waters off Baja California,
between weak high pressure west of the region and lower pressure
across northern Mexico, along with 4 to 6 ft seas. Moderate to 
fresh SE to S winds and 2 to 4 ft seas are noted over the 
northern Gulf of California. Latest satellite imagery showers 
scattered showers and thunderstorms firing along portions of the 
Pacific coast of Mexico.

For the forecast, strong to near-gale N winds will continue to 
pulse across the Tehuantepec region through Sat night. Moderate 
to locally fresh SE flow will persist in the northern Gulf of 
California through Sat. Winds and seas may be higher in the Gulf 
of California in the evenings as showers and thunderstorms over 
mainland Mexico move into the Gulf.

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

High pressure over the NW Caribbean is helping to funnel fresh to
strong NE to E winds over the Papagayo region with seas to 8 ft.
Elsewhere, moderate or weaker winds prevail. Seas are 4 to 6 ft,
primarily in long period SW swell. Scattered moderate to strong 
showers and thunderstorms are active offshore of Panama and Costa
Rica, extending to 180 nm off Costa Rica.

For the forecast, high pressure over the NW Caribbean will 
continue to support fresh to strong NE to E winds over the 
Papagayo region through Sat morning, mainly during the overnight 
and early morning hours. Moderate or weaker winds are forecast 
elsewhere. A moderate southerly swell will continue to impact the
waters west of Ecuador through this weekend. Winds will freshen 
south of the monsoon trough this weekend allowing for seas to 
build across the waters north of 02N. Showers and thunderstorms
will remain active off Panama and Costa Rica through the weekend.

REMAINDER OF THE AREA...

The remnant low pressure of what was Guillermo is near 15N138W, 
with an estimated pressure of 1012 mb. The earlier thunderstorm
activity with the low has now dissipated. Associated winds are 
mainly fresh on the northern side of the low pressure, from 17N
to 27N, west of 135W. This large area of fresh winds is due to
ridging dominating the waters north of 20N and west of 120W. Seas
are estimated to be 7 to 8 ft related to this. Another area of 
low pressure is centered near 11N122W, with an estimated 
pressure of 1009 mb. A large area of disorganized showers and
thunderstorms is located on the north side of the low. This
system has a low chance of developing into a tropical cyclone
during the next 48 hours as it moves west to west-northwest at
around 10 kt. Seas of 5 to 8 ft prevail elsewhere across the 
open waters.

For the forecast, the remnant low of Guillermo will open up to a
trough with diminishing winds as it crosses west of 140W on Fri,
while associated seas will be slower to decay. Otherwise, the 
ridge will linger across the waters north of the convergence zone
with fairly tranquil marine conditions expected. The low near 
11N122W will deepen slightly over the next couple of days, 
allowing strong winds and seas building to 10 ft through Sat from
12N to 16N between 125W and 135W.

$$
Hagen