160
AXPZ20 KNHC 172216
TWDEP

Tropical Weather Discussion...CORRECTED
NWS National Hurricane Center Miami FL
2205 UTC Mon Jun 17 2024

Corrected to update the Special Features section

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
2125 UTC.

...SPECIAL FEATURES...

Central America and southern Mexico Heavy Rainfall Event:
The broad area of low pressure over SE Mexico and western Central
America has moved into the Bay of Campeche and has been
designated as Potential Tropical Cyclone One (PTC One) in the
Atlantic basin. The broad system draws abundant moisture from
the Pacific Ocean into the coastal terrain of Central America
and southern Mexico. This pattern will continue at least through
late week, enhancing heavy rainfall and strong thunderstorms.
This can cause life-threatening conditions that include flooding
and mudslides. Numerous heavy showers and thunderstorms have
already impacted the coasts of Guatemala and the Mexican state
of Chiapas. The main areas impacted by the heavy rainfall will
be northwest Nicaragua, southwest Honduras, El Salvador, coastal
sections of Guatemala and the Mexican state of Chiapas.
Additionally, dangerous surf conditions will impact these
coastal areas through the next few days. Please refer to your
local meteorological and emergency management office bulletins
for more detailed information.

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

The monsoon trough extends from the offshore waters of Mexico
near 13N102W to 07N127W. The ITCZ stretches from 07N127W to
08N140W. Numerous moderate to isolated strong convection is
observed north of 09N and east of 107W. Similar convection is
noted from 05N to 12N and between 110W and 122W.

...OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Refer to the Special Features section above for details on heavy
rainfall.

The persistent enhanced SW-W flow south of southern Mexico
associated with PTC One results in fresh to near gale-force SW
winds. This was confirmed by a recent scatterometer (ASCAT)
satellite pass. The strongest winds are likely associated with the
strong convection in the area. Seas in these waters are 8-11 ft.

A 1026 mb high pressure system over the North Pacific dominates
the remainder of the area. The pressure gradient between the
aforementioned ridge and lower pressures due a low pressure off
southern California result in fresh to strong northerly winds
west of Guadalupe Island, as seen by ASCAT. Northerly swell is
producing seas of 9-11 ft in the area described. Elsewhere in the
Baja California offshore waters, moderate or weaker winds and
seas of 6-9 ft are prevalent. The scatterometer data also showed
moderate to locally fresh southerly winds and seas of 2-5 ft in
the Gulf of California. In the remainder of the Mexican offshore
waters, moderate or weaker winds and moderate seas are
prevalent.

For the forecast, fresh to near strong SW to W winds, rough to
very rough seas, and numerous heavy showers and strong
thunderstorms will impact the offshore waters of southern Mexico
through Fri, primarily off Chiapas, Oaxaca and southeastern
Guerrero. Dangerous surf is also anticipated through Thu along
the coastal areas of this region. Farther north, fresh to strong
NW winds and very rough seas will persist off Baja California
Norte through Tue morning, primarily beyond 120 nm offshore.
Large swell of 8-10 ft will linger in these waters mainly north
of Cabo San Lazaro through this evening before gradually
subsiding through Tue night.

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

Refer to the Special Features section above for details on heavy
rainfall.

Potential Tropical Cyclone One, centered in the Bay of Campeche,
continues to induce a strong monsoonal flow, resulting in fresh
to locally near gale-force SW to W winds along with seas at 8 to
11 ft. Scattered showers and thunderstorms are evident in the
offshore waters of Guatemala and El Salvador. Moderate to fresh
SW winds with 5-8 ft seas and isolated thunderstorms are
occurring offshore of Nicaragua. Moderate to locally fresh
southerly winds and seas of 6-8 ft are occurring south of 01N.
Elsewhere, moderate or weaker winds and slight to moderate seas
prevail.

For the forecast, fresh to strong SW-W winds, rough to very
rough seas and numerous heavy showers and strong thunderstorms
will persist through Fri across the offshore waters of northern
Central America, associated with PTC One. Dangerous surf is also
anticipated through Thu along the coastal areas of this region.
Farther south, rough seas in moderate to large southerly swell will
continue near the Galapagos Islands and offshore of Ecuador through
Tue night.

...REMAINDER OF THE AREA...

Refer to the ITCZ/Monsoon Trough section for convection in the
region.

The enhanced monsoon flow supports fresh to strong S-SW winds
south of the monsoon trough to 06N and east of 120W, as shown by
a recent ASCAT pass. Seas in these waters are 7-10 ft. A 1026 mb
high pressure system near 31N145W dominates the waters north of
the ITCZ and monsoon trough. The pressure gradient between this
ridge and lower pressures off southern California result in fresh
to strong northerly winds and seas of 9-11 ft north of 27N and
east of 127W. Moderate to locally fresh N-NE winds and seas of
6-9 ft are found north of 15N and west of 115W. Elsewhere,
moderate or weaker winds and moderate seas prevail.

For the forecast, the high pressure and related ridge will
gradually weaken starting midweek, which should allow winds and
seas north of 20N to slowly subside after midweek. will dominate
waters west of 120W into the weekend. East of 110W, SW to W winds
are going to increase to between fresh to strong with seas
building to between 8-11 ft by Tue. Scattered moderate
convection is expected to continue near the monsoon trough
through at least midweek. Seas of 7-8 ft will hover around 03S
west of the Galapagos Islands through Fri.

$$
Delgado