254
AXPZ20 KNHC 150930
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Sat Jun 15 2024

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 0600 UTC surface analysis and satellite imagery through
0930 UTC.

...SPECIAL FEATURES...

Central America Heavy Rainfall Event: A Central American Gyre
(CAG) is rapidly developing, with heavy rainfall already
occurring. The first round of excessive rainfall is expected in
Costa Rica and Panama tonight and Saturday, with 8 to 12 inches
along the Pacific coasts. The heaviest rainfall is expected to
occur between Sunday and late next week across portions of
Central America into Mexico.

This rainfall event will cause very hazardous conditions to the
region and could be life-threatening. Please refer to your local
meteorological office bulletins for more detailed information.

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

The monsoon trough extends from 16N98W to 16N112W to 07N123W. The
ITCZ extends from 07N1123W to 09N134W, then from 10N138W to
beyond 11N140W. Scattered moderate and isolated strong convection
is noted from 03N to 17N between 77W and 101W.

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

A 1030 mb high pressure is centered well NE of the area near
33N140W and extends a ridge SE across the Baja California
offshore waters. The pressure gradient between this high and
lower pressure over Mexico is causing moderate to fresh winds
across the Baja California offshore waters north of Cabo San
Lazaro. South of Cabo San Lazaro, gentle to moderate winds
prevail. Seas range 5 to 8 ft within NW swell across the region,
with the highest seas N of 28N and W of Guadalupe Island. In the
Gulf of California, winds are light to gentle, and seas range 2
to 4 ft with the highest seas near the entrance of the Gulf.
Gentle winds prevail over the SW Mexico offshore waters with seas
4 to 6 ft within mixed swell. Across the southern Mexico
offshore waters, the monsoon trough has lifted north around 17N,
bringing moderate to locally fresh winds. Seas are 6 to 8 ft.
Across most of the Mexico offshore waters, smoke from
agricultural fires may be restricting visibility somewhat over
area waters.

For the forecast, fresh to locally strong winds will persist
across the Baja California offshore waters through early next
week. NW swell will move across the Baja California Norte
offshore waters, with seas building 8 to 12 ft through the
weekend and into early next week north of Cabo San Lazaro. Seas
are expected to peak north of Punta Eugenia by Sun night into
Mon, and will subside below 8 ft by Tue night into Wed. Meanwhile,
strong winds are expected near the Tehuantepec region with seas
peaking near 12 ft beginning on Sunday and continuing through
early next week.

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

Refer to the section above for details on the developing Central
American Gyre.

With the monsoon trough displaced farther north than usual, this
is bringing fresh winds across the Colombia and Panama offshore
waters with seas 7 to 9 ft. Across the rest of the Central
American offshore waters, winds are moderate to fresh with 6 to
8 ft seas. Strong thunderstorms continue to impact Central
America, bringing heavy rain and frequent lightning. These storms
could cause hazardous marine conditions. In the Ecuador and
Galapagos Island offshore waters, winds are gentle to moderate.
Seas are 6 to 8 ft within S swell.

For the forecast, an increase in winds, rough seas and
widespread showers and thunderstorms will dominate the Central
America offshore waters this weekend and into early next week.
These widespread showers and thunderstorms are expected to bring
heavy rainfall and hazardous conditions. Fresh to strong winds
and rough seas in the Gulf of Panama will improve by today. By
Sun, these conditions are expected to develop across the offshore
waters from Guatemala to Nicaragua. Meanwhile, seas to 8 ft will
continue around the Galapagos Islands through the weekend.

...REMAINDER OF THE AREA...

Broad ridging dominates the waters north of the ITCZ and monsoon
trough, anchored by a 1030 mb high pressure near 35N140W.
Moderate to fresh winds prevail across waters N of the monsoon
trough and W of 115W with seas 6 to 9 ft. East of 115W, gentle to
moderate winds are noted south of the monsoon trough to 05N.
Seas are 4 to 7 ft across the rest of the Pacific waters.

For the forecast, strengthening high pressure centered NW of the
area will dominate waters west of 120W into the weekend. Fresh to
strong winds from the California Channel Islands southward are
likely to dip south of 30N at times through early next week.
Seas will build to 8 to 12 ft by Sun night into Mon. SW flow
south of the monsoon trough is forecast to continue tonight
between 90W and 115W, supporting seas of 6 to 8 ft. Similar winds
and seas are likely to return there by the end of the weekend
into early next week. Thunderstorms will persist near the monsoon
trough and east of 110W or so through the next couple of days.
Seas to 8 ft will hover around 03S near the Galapagos Islands
through the weekend.

$$
AReinhart