Tropical Weather Discussion
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717
AXPZ20 KNHC 302205
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Wed Jul 30 2025

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
2130 UTC.

...SPECIAL FEATURES...

South of Southwestern Mexico (EP99): Shower activity associated
with a trough of low pressure located several hundred miles
southwest of the southwestern coast of Mexico has become a little
better organized since yesterday. Environmental conditions
appear conducive for additional development, and a tropical
depression is likely to form during the next day or two while the
system moves west-northwestward around 15 mph, remaining well
offshore of the southwestern coast of Mexico. There is a high
chance of tropical development within the next 48 hours.

Refer to the latest NHC Tropical Weather Outlook at
www.hurricanes.gov for more details about these invest areas.

Tsunami Threat: A powerful 8.8 magnitude earthquake occurred at
2325 UTC July 29 off the east coast of Kamchatka, Russia. Tsunami
waves have been observed, and waves reaching more than 3 M above
the tide level are possible along some coasts of Ecuador.
Tsunami waves reaching 1 to 3 M above the tide level are possible
along some coasts of Costa Rica. Tsunami waves reaching 0.3 to 1
M above the tide level are possible along some coasts in Central
and South America. Mariners and coastal interests should consult
local authorities and visit www.tsunami.gov for the latest
information and guidance.

...TROPICAL WAVES...

A tropical wave axis is along 84W, from 04N northward through
central Costa Rica and eastern Nicaragua into the western
Caribbean, moving to the west around 10 kt. Scattered moderate to
strong convection is occurring from 04N to 10N east of 87W.

A tropical wave axis is along 93W, from 03N northward into
southeastern Mexico, moving to the west around 10 kt. Scattered
moderate to strong convection is occurring from 05N to 14N
between 90W and 98W.

A tropical wave axis is along 126.5W, from 04N to 17N, moving to
the west around 5 to 10 kt. Scattered moderate convection is
occurring from 09N to 14N between 119W and 127W.

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

The monsoon trough extends from 09N84W to a 1008 mb low near
12N112W to 09N123W. The ITCZ extends from 09N124W to beyond
11N140W. Widespread moderate to locally strong convection is
noted from 07N to 19N between 100W and 120W.

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

Fresh to strong N to NE winds and 6 to 7 ft seas are occurring
in the Gulf of Tehuantepec as high pressure prevails over the
northwestern Gulf of America. Farther west, scatterometer
satellite data show moderate to fresh SE to NE winds, with
localized strong winds, are occurring well offshore of Jalisco
through Michoacan as EP99 strengthens to the southwest. Altimeter
satellite data show 6 to 8 ft seas in this area. Elsewhere, a
1009 mb low centered near 30.5N114W extends a trough
southeastward through the Gulf of California into Baja California
Sur. The pressure gradient between these features and ridging to
the west is leading to moderate to fresh NW winds and moderate
seas offshore of Baja north of Cabo San Lazaro, as noted on
recent scatterometer data. Gentle to locally moderate SE winds
and slight seas prevail in the Gulf of California.

For the forecast, a trough of low pressure, EP99, is located
several hundred miles southwest of the southwestern coast of
Mexico. Environmental conditions appear conducive for additional
development, and a tropical depression is likely to form during
the next day or two while the system moves west-northwestward
around 15 mph, remaining well offshore of the southwestern coast
of Mexico. There is a high chance of tropical development within
the next 48 hours. Elsewhere, fresh to strong N to NE winds will
pulse in the Gulf of Tehuantepec through this weekend, with the
strongest winds occurring each night and early morning. Winds
will diminish in this region by early next week. Elsewhere,
moderate to fresh NW winds, with locally strong winds, will occur
offshore of Baja California through this weekend.

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

Moderate to fresh E to NE winds and moderate seas are noted in
the Gulf of Papagayo as low pressure prevails in the south-central
Caribbean, and a tropical wave moves westward through Central
America. Generally moderate S winds are ongoing south of the
monsoon trough, with mainly gentle winds noted to the north. Seas
of 4 to 6 ft in S swell dominate the regional waters, as noted on
altimeter data.

For the forecast, fresh to occasionally strong E to NE gap winds
will occur in the Gulf of Papagayo into this weekend as low
pressure dominates the south-central Caribbean. Moderate to
occasionally fresh E winds will extend beyond the Papagayo region
through the waters offshore of El Salvador and Guatemala into
Sat. Looking ahead, fresh S winds are expected offshore of
Ecuador and southern Colombia on Fri. A long-period S to SW swell
will move through the South American waters Fri into this
weekend, leading to rough seas between Ecuador and the Galapagos
Islands. Seas will slowly subside by Sun.

...REMAINDER OF THE AREA...

See the Special Features section above for information on Invest
area EP99.

Recent scatterometer satellite data show strong to locally near-
gale force winds and rough seas of 8 to 10 ft are occurring near
EP99, centered near 12N112W. Farther west, widespread fresh to
locally strong NE winds and 8 to 10 ft seas are noted from 10N to
20N west of 135W, to the east of EP98, centered west of the area
near 12N143W. The rest of the eastern Pacific north of the
monsoon trough and ITCZ is dominated by ridging, stemming from a
1027 mb high centered near 32N139W. Gentle to moderate NE winds
are noted north of 25N and west of 130W, near the center of the
high pressure, while moderate to fresh N to NE winds and 4 to 7
ft seas are noted over the rest of the region. South of the
monsoon trough and ITCZ, away from EP98 and EP99, moderate to
locally fresh SE winds and moderate seas prevail.

For the forecast, a trough of low pressure, EP99, is located
several hundred miles southwest of the southwestern coast of
Mexico. Environmental conditions appear conducive for additional
development, and a tropical depression is likely to form during
the next day or two while the system moves west-northwestward
around 15 mph, remaining well offshore of the southwestern coast
of Mexico. There is a high chance of tropical development within
the next 48 hours. Elsewhere, fresh to locally strong NE winds
occurring east of EP98, centered west of 140W, will diminish
through Thu morning. Rough seas in this region will continue
through Thu and expand farther east toward 130W on Fri and Sat.
Widespread moderate to fresh N to NE winds will prevail north of
the monsoon trough and ITCZ into this weekend as high pressure
persists north of the region.

$$
ADAMS