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Eastern North Pacific Tropical Weather Discussion

AXPZ20 KNHC 120258

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Wed May 12 2021

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 0000 UTC surface analysis and satellite imagery through
0240 UTC.


The monsoon trough extends from 10N74W to 07N80W to 10N106W, then
resumes from 13N111W to 07N129W. The ITCZ continues from 07N129W
to 04N140W. Scattered moderate and isolated strong convection 
is noted from 05N to 10N between 80W and 88W, and from 10N to 13N
between 108W and 110W. Scattered moderate convection is noted
from 02N to 04N between 78W and 80W, from 01N to 05N between 82W
and 85W, and from 06N to 11N between 100W and 104W. 

Scattered moderate and isolated strong convection is also noted
within 75 nm of the coasts of Guatemala and El Salvador.


The remnant low pressure 1009 mb of Andres is located south-
southwest of the Revillagigedo Islands near 16N112.5W. A small
area of lingering 7-8 ft seas is near the low. Seas are 4-7 ft  
elsewhere across the offshore waters in a mix of long period SW 
and NW swell, except 3 ft or less in the Gulf of California. A 
weak and broad ridge covers the waters west of Baja California 
with gentle to moderate NW-N winds prevailing. Elsewhere, light 
and variable winds prevail. Hazy or smokey conditions may be 
evident near the coast south of Cabo Corrientes to the
Tehuantepec region, but a slight southerly component to the 
winds along with afternoon sea breezes are probably keeping most 
of these conditions confined to onshore for now. 

For the forecast, the seas around the Revillagigedo Islands will
subside through early Wed as the remnant low of Andres 
dissipates farther south. Elsewhere, fresh southerly winds will 
pulse in the northern Gulf of California this weekend, increasing
to fresh to strong Sat night as a trough moves through the area.
Gentle to moderate winds will prevail elsewhere. A moderate NW 
swell will subside in the waters west of Baja California through 
Thu, with another set arriving Sat. Farther south, building high 
pressure in the Gulf of Mexico may allow strong gap winds in the 
Tehuantepec region Thu through early Sat with building seas.


Fresh to strong winds are in the Papagayo region, with gentle to
moderate winds elsewhere. Seas are in the 3-6 ft range in mixed 
long period NW and SW swell, except 5-7 offshore of Ecuador and 
to 7 ft in the Papagayo region.

For the forecast, moderate to fresh winds will prevail in the 
Papagayo region, pulsing to fresh to strong during the overnight 
hours through the rest of the week and into the weekend. Gentle 
to moderate winds will prevail elsewhere. Moderate southerly swell
will subside tonight, with another set arriving Fri, and then a 
larger, reinforcing set this weekend. 


The remnant low of Andres 1009 mb is centered near 16N112.5W 
moving westward at around 5 kt. Associated winds are 20 kt or
less while a small area of 6-8 ft seas is near the low. This
remnant low will dissipate by early Wed with seas subsiding to
less than 8 ft.

Elsewhere, a broad ridge covers the waters north of the 
ITCZ. Gentle to moderate trades, locally fresh, dominate the 
waters north of the ITCZ. Gentle to moderate winds prevail 
elsewhere. Northerly swell producing seas of 7-8 ft continues to 
propagate across the northern waters north of 25N between 125W 
and 135W. Elsewhere, seas are in the 6-7 ft in a mix of mainly 
long period southerly and northerly swell, except to 8 ft along
the equator between 105W and 140W.

For the forecast, fairly tranquil marine conditions with moderate
trades will prevail through the remainder of the week and 
weekend, along with mainly 5-7 ft seas. Southerly swell crossing 
the equator will help to maintain seas to 8 ft across the 
southern waters through midweek with a reinforcing set of 
southerly swell arriving east of 120W this weekend which will 
build seas to 7-9 ft south of 10N and east of 120W.