Tropical Weather Discussion
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004
AXPZ20 KNHC 172005 CCA
TWDEP

Tropical Weather Discussion...Corrected
NWS National Hurricane Center Miami FL
1845 UTC Thu Apr 17 2025

Corrected forecast for Offshore Waters Within 250 nm of
Mexico

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
1830 UTC.

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

A trough axis extends from low pressure in northwest Colombia to
09N84W to 08N88W to 06N93W, where it transitions to the ITCZ
to 05N102W to 06N112W to 06N120W to 06N125W. Scattered moderate
to strong convection is from 03N to 06N between 86W-89W, and
within 180 nm south of the trough between 84W-86W. Scattered
moderate to isolated strong convection is within 120 nm south of
the ITCZ between 105W-112W, within 120 nm north of the ITCZ
between 115W-120W, within 120 nm north of the ITCZ between
115W-120W, also within 60 nm south of the ITCZ between 102W-105W
and between 112W-115W.

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

The gradient associated to high pressure that extends from the
Gulf of America southwestward to southeastern Mexico continues to
support strong to near gale north winds in the Gulf of
Tehuantepec extending south to near 14N as seen an overnight
scatterometer satellite data pass. Peak seas with these winds
are around 9 ft. Deep-layer low pressure offshore of southern
California is producing a weak surface low there, with an
elongated trough extending southwestward to near 29N130W. This
area of low pressure is blocking high pressure farther NW from
building unobstructed into the Baja waters. However, this high
pressure does extend a weak ridge eastward and below the surface
trough to Baja Sur. The associated pressure gradient between this
ridge and lower pressure across the Gulf of California is
supporting gentle winds across the waters of Baja Norte, and
moderate to locally fresh northwest to north winds across the
Baja waters south of Punta Eugenia becoming northerly across the
Revillagigedo Islands. Seas are 4 to 5 ft N of Punta Eugenia and
5 to 7 ft southward to the Revillagigedo Islands. Elsewhere over
the Pacific offshore waters, winds are moderate or weaker with
seas of 4-5 ft in mixed NW and S swell.

The Santa Maria Volcano located in southwestern Guatemala near
14.8N91.6W is presently undergoing continuous volcanic ash
emissions. The volcanic ash near the volcano is moving to
southwest. Latest GOES-E satellite imagery shows resultant hazy
skies along the coast of Guatemala, with similar conditions just
offshore the coast. Reduced visibility is presently more likely
to be near the coast. Mariners are encouraged to be aware of the
latest updates on the status of this volcano.

In the Gulf of California, southwest to west winds in the
northern section of the Gulf that earlier were at gale-force
have recently diminished to strong speeds along with seas
to around 8 ft. These winds will diminish further, to 15 kt or
less, this afternoon. Winds will gradually diminish there
through Fri, except becoming fresh to strong from the southwest
Fri night. High pressure extends across Baja and northwestern
Mexico tonight ahead of a strong frontal system developing across
the western U.S., and will also induce westerly gap winds each
of the next few nights across central portions of the Gulf,
peaking at strong speeds. Gentle winds will continue in the
southern section of the Gulf through Sat along with seas of 2 to
4 ft.

For the forecast, winds over the northern Gulf of California
are expected to again pulse to strong to near gale-force
tonight. Fresh to locally strong W gap winds will also develop
during this time across central portions of the Gulf. Strong
to near gale-force north winds in the Gulf of Tehuantepec will
gradually diminish today before the gap wind flow ends there
tonight. Elsewhere, winds across the Mexican Offshore zones will
remain moderate or weaker north of Punta Eugenia, and moderate
to fresh off Baja California Sur through Sat night, then become
moderate to locally fresh north of 20N Sun afternoon through Mon.

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

High pressure across the central Atlantic and eastern Gulf of
America extending into the NW Caribbean is inducing gap winds
across the Pacific waters of Central America, and fresh to
locally strong NE to E gap winds across the Papagayo region
tonight. Seas are currently 5 to 8 ft there. NE winds across the
southwestern Caribbean are producing fresh N winds over the Gulf
of Panama extending to 06N, where seas are 4 to 6 ft. Elsewhere,
between Ecuador and the Galapagos Islands, winds are gentle to
moderate with 4-6 ft seas in S swell. Large clusters of
scattered to numerous showers and thunderstorms continue to
shift westward across the waters south of 08N, moving offshore
northern Ecuador and Colombia and passing along the Pacific
coasts and waters of Panama and Costa Rica east of 90W. The
strongest of the thunderstorms have the potential to produce
wind gusts to gale force and locally rough seas.

For the forecast, the surface ridge over the eastern Gulf of
America that extends into the northwestern Caribbean will shift
gradually eastward to the Atlantic waters between Cape Hatteras
and Bermuda during the next several days to support fresh to
strong NE to E gap winds across the Papagayo region, pulsing to
near 30 kt at night through Sat night, then diminish slightly
through Mon night. The same high pressure will force moderate to
fresh N winds across the Gulf of Panama to near 5N through Sat
night along with peak seas to around 6 ft. Locally strong N to
NE winds are expected in the Gulf of Panama tonight and Fri
night. Moderate SW swell will move into the regional waters Mon.

...REMAINDER OF THE AREA....

A modest surface ridge dominates the waters W of 130W tonight,
and extends a ridge south then weakly eastward over the
subtropical waters west of the Baja California Sur waters, to
the south of a surface trough extending from offshore of southern
California to near 29N130W. A trough is located just west of
the ITCZ from 02N129W to 02N129W. Scattered moderate to isolated
strong convection is noted west of the trough to 130W and from
04N to 07N. This pattern continues to produce moderate to locally
fresh NE winds between the ITCZ and 21N, W of 125W per overnight
scatterometer satellite data passes. Seas in this region are 7-8
ft in N swell. N of 21N, gentle to moderate N to NE winds
prevail, with seas of 5 to 7 ft in mixed NW and NE swell. S of
20N between 100W and 125W, moderate to locally fresh trade winds
prevail, with seas of 5 to 8 ft in mixed N and E swell. Scattered
moderate isolated strong convection is occurring near the ITCZ
to 08N.

For the forecast, little change in the winds across the open
waters is expected for the next several days, except for slightly
stronger trades occurring W of 120W over the weekend. The
persistence of these winds will lead to building seas of 8 to 9
ft, subsiding Mon. Otherwise, new moderate northerly swell is
forecast to reach the far northern waters west of the Baja
California Peninsula Mon, building seas to around 8 ft.

$$
Aguirre