000
AXPZ20 KNHC 131616
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Sat May 13 2023

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 1200 UTC surface analysis and satellite imagery through
1540 UTC.

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

The monsoon trough extends from 10N75W to near 05N83W to 
08N98W to 06N102W. The ITCZ extends from 04.5N117W to beyond
03N140W. Scattered moderate isolated strong convection is noted 
from 02N to 06N east of 109W. Scattered moderate to strong
convection is noted from 01.5N to 07.5N between 111W and 140W.

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

The gradient between high pressure NW of the area and surface 
troughing over NW Mexico is supporting moderate to fresh NW to N
winds across the offshore waters of the Baja California 
Peninsula that extends southward to the Revillagigedo Islands 
Associated seas are 5-7 ft. Gentle to moderate NW to W winds 
generally prevail across the remaining Mexican offshore waters 
from Cabo Corrientes to Tehuantepec. Seas there are 5-7 ft in 
mixed NW and SW swell. In the Gulf of California, mainly light 
and variable winds prevail, with seas of 3 ft or less, except 3-5
ft near the entrance in S-SW swell. Hazy skies persist across the
near and offshore waters from Manzanillo to Tehuantepec due to 
lingering smoke from agricultural fires.

For the forecast, high pressure NW of the area will shift 
northward and weaken through the weekend, leading to a weak 
pressure gradient across the region, and gentle to moderate winds
area-wide Sat through Wed. A surge of fresh to strong gap winds 
is possible in the Gulf of Tehuantepec Mon morning through Tue 
afternoon, building seas to 6-8 ft. Reduced visibilities in haze 
are possible in the S and SW Mexico offshore waters due to smoke 
produced by agricultural fires. 
 
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA,
AND WITHIN 750 NM OF ECUADOR...

A weak pressure gradient across the region continues to support
winds of only light to gentle speeds across the majority of the 
Central America and northern South America offshore waters, with
very localized gap winds of 15-20 kt downwind of the Gulf of 
Papagayo. Seas are 5-8 ft in S-SW swell offshore Ecuador to the 
Galapagos Islands, and 3-6 ft elsewhere. Scattered showers and 
thunderstorms continue offshore of Colombia. Hazy skies persist 
from the Papagayo region to Tehuantepec due to lingering smoke 
from ongoing agricultural fires, with visibilities likely near 
5 nm downwind of Papagayo and Nicaragua.

For the forecast, seasonally tranquil conditions will persist 
across the offshore waters through early next week. Moderate gap
winds across the Papagayo region will pulse to fresh to locally
strong each night through Mon morning. Building SW swell to 
around 8 ft should begin reaching the Galapagos Islands Sun 
night, then reach the nearshore waters of Central America on Tue,
resulting in seas of 6-7 ft. Reduced visibilities in haze are 
expected from the Guatemala to the Costa Rica offshore waters due
to smoke produced by ongoing agricultural fires.

...REMAINDER OF THE AREA...

The gradient between subtropical 1022 mb high pressure near 
29N132W and lower pressure along of the ITCZ is supporting 
moderate to locally fresh NE to E tradewinds from 06N to 21N and 
west of around 117W per overnight scatterometer data. Seas are 
6-9 ft across this area per recent altimeter passes. Light to 
gentle variable winds and 5-7 ft seas in mixed swell are north 
of 21N and west of 125W near the high, except just SE of 30N140W 
where newly arriving NW swell is building seas to 7-9 ft, with 
increasing S winds of 15-20 kt just NW of the area ahead of an 
approaching cold front. Elsewhere, winds are gentle to moderate, 
with 5-8 ft seas in mixed swell, highest S of the Equator and 
west of 104W.

For the forecast, little change is expected in the tradewinds 
through today, with seas generally 6-9 ft in merging NW and S 
swell, and NE wind waves. Tonight through Mon, the trades are 
anticipated to begin a weakening trend as the high pressure 
weakens and shifts farther northward. Fresh to locally strong 
winds north of the area offshore Point Conception, California 
will send fresh N seas of 6-8 ft southward to 27N between 120W 
and 133W this afternoon through the remainder of the weekend.

A cold front will move slowly into the far NW waters Sun 
afternoon, with a brief period of fresh to strong southerly winds
ahead of it. The front will weaken and gradually dissipate 
through Wed. NW swell generated well NW of the area will move 
into the NW waters through Mon to produce seas of 8-11 ft north 
of 20N and west of 135W. Meanwhile, cross equatorial S to SW 
swell will maintain seas around 8 ft along and south of the 
Equator. New cross-equatorial S-SW swell should reach the Equator
late Sun and build seas 8-10 ft south of the ITCZ early Mon 
through Tue night before subsiding. Tranquil conditions will 
dominate across the open waters by the middle of next week.

$$
Stripling