Tropical Weather Discussion
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154
AXPZ20 KNHC 092127
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Sat Nov 9 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 1800 UTC surface analysis and satellite imagery through
2100 UTC.

...SPECIAL FEATURES...

Excessive Rainfall Risk in Southern Central America: Persistent
SW flow in the eastern Pacific region will continue to bring
abundant tropical moisture across southern Central America. This
combined with a diffluent pattern aloft and the presence of a
Central America Gyre (CAG) will support the potential for heavy
rainfall across southern Central America into early next week.
This weather pattern may particularly impact Costa Rica and
Panama. Global models continue to show the CAG having a connection
to the long moisture fetch from the eastern Pacific through next
Thu. This information is provided by the Weather Prediction
Center`s International desk team. Please refer to your national
weather agency for details.

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

The monsoon trough extends from 14N92W to 1011 mb low pressure
near 11N101W, to 1011 mb low pressure near 11N114W to 09N130W to
10N140W. Scattered moderate to isolated strong convection is
noted from 09N to 12N between 101W and 104W. Scattered moderate
convection can be found from 11N to 13N between 93W and 99W, and
from 07N to 11N between 110W and 140W.

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

A ridge dominates the offshore forecast waters of Baja California
producing mainly light to gentle winds. Seas are 4 to 6 ft within
these winds. Scatterometer data provide observations of moderate
to fresh NW winds across the central and southern parts of the
Gulf of California while gentle to moderate NW winds prevail
across the northern part of the Gulf. These winds are the result
of the pressure gradient between a ridge over northern Mexico and
a meandering trough over the Gulf of California and the Baja
California Peninsula. Seas are 4 to 6 ft with the strongest
winds. Gentle to moderate winds and moderate seas persist
elsewhere.

For the forecast, the fresh NW winds and associated moderate
seas across the central and southern Gulf of California will
diminish later today. Building high pressure west of the region
will support fresh NW winds off Baja California Norte late Mon
into Tue. This will be followed by large NW swell, reaching
Guadalupe Island by Tue night, then offshore of Cabo San Lazaro
by Wed night. Farther south, moderate to fresh N winds are
expected in the Tehuantepec region through Tue. Then, winds are
predicted to increase to fresh to strong speeds Wed night through
Thu night as a ridge establishes across the eastern slopes of
the Sierra Madre Mountains in Mexico.

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

Please refer to the Special Features section for details on an
Excessive Rainfall Risk in Southern Central America.

Satellite derived wind data indicate moderate to fresh S to SW
winds across the offshore waters of Panama, including the Gulf of
Panama. These winds are transporting tropical moisture across
southern Central America, now supporting scattered showers and
thunderstorms across the area. Gentle to moderate winds and
moderate seas are noted elsewhere.

For the forecast, moderate to fresh SW to W winds and seas of 6
to 8 ft will continue to impact the offshore waters of Costa Rica
and western Panama through Mon. Gentle to moderate winds and
moderate seas will persist elsewhere.

...REMAINDER OF THE AREA...

A couple of low pressure areas persist along the monsoon trough.
Fresh to strong S to SW winds are noted just SE and S of the
remnant low of Fourteen-E now located near 11N101W. Seas are 8
to 9 ft within these winds. Scattered moderate to isolated
strong convection is still occurring within about 150 nm on the
west semicircle of the low center. Moderate to locally fresh N
winds are seen on the NW quadrant of the low pressure located
near 11N114W. Farther to the northwest, large NW swell continues
to propagate across the NW waters, particularly N of 23N and W
of 130W. Seas are 8 to 9 ft there. A trough persists across the
north waters and extends from 30N129W to 21N127W. This is
breaking up the subtropical ridge and allowing mainly gentle to
moderate winds to persist elsewhere, with combined seas of 5 to 7
ft in mixed swell.

For the forecast, the NW swell event will continue to push to the
southeast, covering most of the area N of 20N and W of 130W by
tonight before decaying below 8 ft late on Sun. A more substantial
group of NW swell will follow by Mon night, with wave heights of
8 to 13 ft covering much of the region north of 10N and west of
115W through Thu as another swell event reaches the forecast
region. By Thu, a strong high pressure is expected to dominate
the forecast area bringing increasing winds. Farther to the
southeast, the fresh to strong SW flow and associated seas will
diminish in strength and areal extent through Sun night.

$$
GR