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Eastern North Pacific Tropical Weather Discussion



000
AXPZ20 KNHC 280902
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
649 UTC Mon May 28 2018

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
0815 UTC. 

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

The monsoon trough extends from 13N92W to 10N103W to 09N125W, 
then transitions to the ITCZ which continues to beyond 09N140W. 
Scattered moderate and isolated strong convection is present from
06N to 11N between 102W and 126W. Scattered moderate within 60 
nm either side of a line from 07N130W to 10N136W.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

An expansive ridge dominates the region W of 110W. A 1032 mb 
high centered near 37N137W extends SE across the region to near 
the Revillagigedo Islands. Fresh to locally strong NW to N winds 
across the offshore waters of Baja California will become fresh 
Mon and Tue, then moderate Wed and Thu. Seas of 6 to 8 ft will 
diminish gradually to between 5 and 6 ft on Tue. Long period NW 
swell will cause seas N of 27N to build to between 7 and 8 ft Thu
and Thu night.

Gulf of California: Gentle to moderate NW winds are expected 
across the Gulf waters through Tue night, with strong afternoon 
and evening sea breezes recurring along the Mexican coastline 
from Mazatlan to Guaymas Mon. A low pressure trough developing 
over the Baja Peninsula will cause winds over the Gulf to become 
light to gentle by Wed. The same trough of low pressure will 
bring fresh to locally strong winds to the waters N of 29N Wed 
night and Thu.

Gulf of Tehuantepec: Winds are expected to be light and variable
during the next few days.

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

The monsoon trough is gradually shifting back to the S as 
persistent elongated low pressure over Central America and the 
Yucatan peninsula weakens. This trend will continue across the 
regional Pacific waters through at least Thu as the trough 
continues to slowly sink S and support light to moderate SW to W 
winds and seas of 4 to 6 ft in SW swell for the waters west of 
Central America.

REMAINDER OF THE AREA...

Elsewhere, the ridge building over the north central Pacific is 
producing a modest pressure gradient across the trade wind belt, 
with moderate to fresh winds observed in satellite-derived wind 
data from 09N to 25N to the west of 120W. Seas are running 6 to 9
ft across this zone this morning and will change very little 
through Tue night. The high is forecast to shift NW Tue through 
Wed and then migrating W later in the week. This will produce a 
very slight decrease in areal coverage of the fresh trade winds 
into mid week. Winds N of the ITCZ between 10N and 15N are 
forecasted to become locally strong Mon night through Wed.

Deepening low pressure over the Desert SW of the U.S. will 
combine with building high pressure W of California to tighten 
the pressure gradient along the California coast. Long period N 
swell generated by these winds will cause seas N of 25N between 
120W and 135W to build to between 8 and 10 ft by Wed morning. 
This area of 8 ft seas will expand to cover all of the waters N 
of 25N by Thu afternoon, then seas will subside as the swell 
disperse.

$$
CAM