Skip Navigation Links
NOAA NOAA United States Department of Commerce

Eastern North Pacific Tropical Weather Discussion



877 
AXPZ20 KNHC 210919
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0919 UTC Sun Apr 21 2019

Tropical Weather Discussion for the eastern Pacific Ocean from
the Equator to 32N, east of 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 trough extends from 10N84W to 06N90W to 06N96W. The ITCZ
continues from 06N96W to 09N115W to 07N125W to 05N135W to beyond
04N140W. Scattered moderate and isolated strong convection is
noted from 02N to 06N between 77W and 81W, from 02N to 04N
between 93W and 97W, within 60 nm north of the ITCZ between 97W 
and 100W, and within 120 nm north of the ITCZ between 117W and 
128W.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO... 

A broad high pressure ridge persists over the offshore waters
west of Baja California. The pressure gradient between this ridge
and a low pressure trough over Baja California supports moderate
NW winds north of Cabo San Lazaro with seas generally 5-7 ft. A
weakening cold front or trough will cross the region today with 
fresh winds developing off Baja California Norte and seas building
to 8-9 ft. NW swell will continue impacting the northern waters 
through Mon night, then seas will subside through midweek.

Gulf of California: A 1008 mb low pressure center over the 
northern Gulf of California is likely supporting fresh to strong 
SW to W gap winds north of 29.5N. These winds will quickly 
diminish this morning. Otherwise, light to gentle winds will 
prevail across the Gulf through Thu.

Gulf of Tehuantepec: A recent partial scatterometer pass showed
fresh to strong N winds over the Gulf of Tehuantepec. Seas likely
reach 10 ft in the Gulf, while a plume of 7-9 ft seas extends 
well downstream of the region based on 05Z altimeter data. Winds 
are expected to diminish to gentle speeds by this afternoon. 
Looking ahead, a weak pressure gradient over the region will 
result in variable, light to gentle winds across the area Mon 
through Thu.

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

Gulf of Papagayo: Fresh to strong NE to E winds will pulse across
the Gulf of Papagayo and downwind to near 90W through Mon night.
Winds will be strongest during the overnight and early morning 
hours with the assistance of the nocturnal drainage flow. As the
pressure gradient weakens through midweek, winds will diminish 
to moderate to fresh speeds with seas less than 8 ft. Looking
ahead, winds and seas will likely continue subsiding through Thu
night.

Gulf of Panama: Moderate N to NE breezes will prevail across the
Gulf of Panama this week with seas generally 3-5 ft in mixed SW
swell and NE wind waves. 

Elsewhere, light to gentle winds will persist across the region
with seas of 4-6 ft in S to SW swell. Seas will peak around 7 ft
today SW of the Galapagos Islands.

REMAINDER OF THE AREA...

A high pressure ridge extends SE across the northern waters
towards the Revillagigedo Islands. The pressure gradient between
this ridge and the ITCZ is supporting fresh trade winds south of
20N west of 125W based on recent ship obs and the latest available
scatterometer data. Altimeter passes in this region indicate 8-9
ft seas within the trades south of the ridge. These conditions
will generally persist through Mon night as high pressure remains
anchored north of the area. The high will weaken Tue through Thu
in response to low pressure approaching from the west. This will
allow winds and seas to subside through midweek.

A set of NW swell associated with a weakening cold front will 
move into the far northern waters later today. Seas will build to
9 ft NW of Guadalupe Island by tonight and remain 8 ft through
Mon night. Elsewhere, S to SW swell will produce seas to 8 ft
generally south of the Equator and west of 110W early this week.

$$
Reinhart