668 
AXPZ20 KNHC 180905
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Sun May 18 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 0600 UTC surface analysis and satellite imagery through
0900 UTC.

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

A monsoon trough extends westward from central Costa Rica across
09N100W to 08N124W. An ITCZ continues west-southwestward from 
08N124W to beyond 06N140W. Scattered moderate convection is 
occurring near both features from 05N to 11N between 77W and 
140W.

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

A broad surface ridge extends southeastward from a 1032 mb high
near 35N145W across 30N140W to just southeast of the
Revillagigedo Islands. This feature is supporting moderate to
fresh NW winds and seas of 5 to 7 ft west of Baja California and
near the Revillagigedo Islands. A surface trough extending 
southward from southern California is causing fresh to locally 
strong SW winds and 4 to 5 ft seas at the northern Gulf of 
California. Gentle to moderate NW winds with seas at 2 to 4 ft 
are present for rest of the Gulf. Light to gentle winds and seas
of 4 to 6 ft in mixed moderate swells prevail across the southern
Mexico offshore waters.

For the forecast, the ridge will continue to support moderate to
fresh NW to N winds with moderate to locally rough seas in large
NW swell west of Baja California through Mon, roughest seas 
anticipated north of Punta Eugenia. Afterward, gentle to moderate
NW to N winds with gradual subsiding seas should prevail through
Thu. A low pressure moving across southern California will 
maintain fresh to locally strong SW to W winds for the northern 
Gulf of California until later morning before becoming mainly 
gentle this afternoon. Mostly gentle winds and slight to moderate
seas, primarily in SW swell are expected elsewhere through Thu.

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

Abundant moisture is coupling with convergent surface winds to 
trigger scattered heavy showers and strong thunderstorms across 
the offshore waters of El Salvador and Nicaragua. Refer to the
ITCZ/Monsoon Trough section for additional convection in the
region, including offshore waters of Costa Rica and Panama. 
Otherwise, mostly gentle SE to SW winds and seas of 4 to 6 ft 
mixed moderate swells are evident in the Central America offshore
waters. For the waters off Colombia and Ecuador, and near the 
Galapagos Islands, gentle to moderate SE to SW winds with 3 to 6 
ft in moderate southerly swell exist.

For the forecast, periods of showers and thunderstorms will 
continue across the offshore waters of Nicaragua, Costa Rica, 
Panama and Colombia through at least Mon morning. Otherwise, 
light to gentle winds are forecast across the Central America 
offshore waters through Thu night. For waters between the coast 
of Ecuador and the Galapagos Islands, gentle to moderate S winds 
along with moderate seas in SW swell will prevail.

...REMAINDER OF THE AREA....

A large dome of 1032 mb high near 35N145W continues to dominate
the region with moderate to locally fresh N to ENE winds and 5 
to 7 ft seas in moderate northerly swell, north of 20N and west 
of 120W. Tighter gradient between the high and ITCZ is generating
moderate to fresh NE winds and seas of 6 to 9 ft from just north
of the ITCZ to 20N and west of 120W. East of 120W, gentle NW to 
NNE winds and 5 to 6 ft seas are seen from the monsoon trough 
northward to 20N/17N. South of the ITCZ/monsoon trough, gentle to
moderate SE to SSW winds with seas at 6 to 7 ft prevail west of 
92W.

For the forecast, a slight strengthening of the high will cause
NNE to ENE winds north of 20N and west of 122W to become fresh 
to locally strong, and seas building to 7 to 10 ft from Mon
afternoon through Tue. Winds and seas from the ITCZ to 20N and
west of 120W should gradually subside starting Tue night and 
Wed. South of the ITCZ/monsoon trough, a new SW swell is going to
cause seas to build slightly near midweek.

$$

Chan