231
AXPZ20 KNHC 131603
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Thu Jun 13 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 1200 UTC surface analysis and satellite imagery through
1530 UTC.

...SPECIAL FEATURES...

A Central American Gyre (CAG) is rapidly developing. Heavy
rainfall is already occurring, and the main event is not at its
peak yet. The persistent moist onshore flow over portions of
Guatemala, Chiapas, Honduras, and El Salvador will favor days of
intermittent rounds of heavy precipitation. Excessive rainfall is
also expected over Costa Rica and Panama, from Friday through the
weekend, producing 8-12 inches of rain across these areas. This
scenario is common during the developing of La Nina. Please refer
to your local meteorological office bulettins for more detailed
information.

...TROPICAL WAVES...

A tropical wave is in the far eastern portion of the tropical
eastern Pacific, with axis along 81W from Panama to near 03N,
moving west at 5 to 10 kt. Scattered moderate isolated strong
convection is noted N of 02N and E of 82W.

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

The monsoon trough extends from 12N87W to 16N96W to 08N126W. The
ITCZ extends from 08N126W to 09N140W. Scattered moderate and
isolated strong convection is from 05N to 16N between 90W and
106W.

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

High pressure centered well NE of Hawaii extends a ridge
southeastward to just W of the Revillagigedo Islands. This
pattern supports moderate to fresh NW to N winds across the Baja
offshore waters. Seas are generally 5 to 7 ft in NW swell. A
surface trough extends across the Gulf of California along 110W
to south of Baja California. Moderate winds are on either side
of the trough in the central and southern Gulf of California,
with light and variable winds in the northern Gulf of California.
Seas are 1 to 3 ft in the Gulf of California, except to 4 ft
near the entrance. Gentle winds dominate the remainder of the
Mexican offshore waters, except for S of 14N, where the monsoon
trough has lift N to. S of the trough, moderate to locally fresh
SW winds prevail. Seas through the waters S of Baja California
are 4 to 7 ft in mixed SW and NW swell. Thunderstorms persist
across the waters south of 17N and east of 105W. North of 15N
away from any convection and extending to offshore Jalisco, smoke
from agricultural fires may be restricting visibility somewhat
over area waters.

For the forecast, troughing will extend from the Gulf of
California to near the Revillagigedo Islands with broad ridging
northwest of there. A relatively tight pressure gradient will
yield an increase in winds on both sides of the troughing into
the weekend. NW swell will impact waters offshore Baja California
this weekend into early next week, leading to seas of 8 to 13 ft
north of Cabo San Lazaro by Sun. A broad area of low pressure
could form late this week a couple of hundred nautical miles off
the coast of southern Mexico or Guatemala. Some slow development
is possible this weekend and early next week while the system
meanders near the coast. Thunderstorms will impact the waters
offshore southern Mexico through the weekend.

...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.

The monsoon trough remains located farther north than its usual
position for this time of year, and currently extends along the
coast of Guatemala then across El Salvador. Moderate southerly
winds prevail across area waters. Seas are generally 4 to 7 ft in
SW swell, except 3 to 5 ft inside the Gulf of Panama and in the
lee of the Galapagos Islands.

For the forecast, monsoonal winds, associated seas, and numerous
thunderstorms will dominate the region through the end of the
week. A broad area of low pressure could form Fri a couple of
hundred nautical miles off the coast of southern Mexico or
Guatemala. Some slow development is possible this weekend and
early next week while the system meanders near the coast. This
will allow for the monsoon trough to lift even farther northward
toward the Gulf of Tehuantepec, with winds to the west of 90W
increasing to fresh to locally strong, leading to building seas
of 8 to 12 ft at times, highest late weekend into early next
week. Meanwhile, fresh to strong SW winds are expected to develop
west of Colombia Fri and shift into the Gulf of Panama Fri night
and Sat before diminishing. Seas are likely build to around 8 ft
there with these winds.

...REMAINDER OF THE AREA...

A surface trough extends from 29N122W to 25N126W with moderate
to fresh winds and seas of 7 to 9 ft to the W of it. Otherwise,
broad ridging dominates the waters north of the monsoon trough
and ITCZ, with mainly gentle winds and 5 to 7 ft seas in mixed
swell west of 110W. To the east of 110W, fresh winds are south
of the monsoon trough north of 03N, along with seas of 7 to 9 ft.
Mainly gentle to moderate winds and 5 to 7 ft seas in S to SW
swell are elsewhere east of 110W.

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 this weekend into early next
week, with seas building to 8 to 13 ft by the end of the
weekend. SW flow south of the monsoon trough is forecast to be
fresh today between 90W and 110W, supporting seas of 7 to 9 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 at least the
next couple of days.

$$
ERA