000
AXPZ20 KNHC 180357
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Sat Nov 18 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 0000 UTC surface analysis and satellite imagery through
0340 UTC.

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

The monsoon trough extends from Costa Rica near 10N86W to 
07N105W to low pressure near 11N115W 1009 mb to 08N126W to 1011 
mb low pressure near 10N136W to 10N140W. Scattered moderate to 
isolated strong convection is from 05N to 10N between 89W and 
100W, and from 09N to 12N between 115W and 119W.

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

Fresh to strong NW to N winds are in the Gulf of Tehuantepec 
north of 15N. A 1016 mb high pressure is centered offshore 
central Baja California near 24N116W. A rather weak gradient in 
place is allowing for generally light to gentle winds offshore 
Baja California, to the north of Cabo San Lazaro. Moderate to
locally fresh NW to N winds are within 60 nm offshore Baja 
California Sur, to the south of Cabo San Lazaro. Seas of 5-7 ft 
prevail west of Baja California in a NW swell. In the southern
half of the Gulf of California, fresh to strong NW winds are
occurring with 5 to 7 ft seas. In the northern Gulf north of
28.5N, winds are gentle with 1 to 2 ft seas. Gentle W to NW 
winds prevail elsewhere offshore between Jalisco and Guerrero, 
where seas are 4-6 ft.

For the forecast, the fresh to strong N winds will continue in 
the Gulf of Tehuantepec through Sat night before diminishing 
early Sun. The pressure gradient between high pressure just west
of Baja California and lower pressure over northern Mexico will 
support fresh to strong NW winds across the central and southern
Gulf of California through tonight, diminishing to moderate to
fresh Sat through Sun. These winds will then expand into 
northern portions of the Gulf of California and increase to
strong early Mon morning through Tue. West of Baja California, 
NW to N winds will increase to fresh Sat afternoon, then increase
to fresh to strong Sun through Sun night. Large NW swell will
enter the waters west of Baja California Sun night into Mon.
Looking ahead, the next gale-force gap wind event in the Gulf of
Tehuantepec is possible during the middle of next week. 

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

Fresh to locally strong SW winds are likely occurring offshore 
of Costa Rica. Seas are in the range of 6-8 ft in this area. 
Elsewhere south of the monsoon trough, moderate SW winds are 
ongoing with seas of 5-7 ft. Gentle to moderate winds prevail N 
of 09N, along with seas of 5-7 ft in mixed swell.

For the forecast, light to gentle winds will prevail N of 09N 
through the forecast period. Fresh SW winds will continue 
offshore Costa Rica and western Panama through Sat night, with 
seas to 8 ft offshore Costa Rica tonight. Winds will diminish Sun
into early next week under a weak pressure pattern.

...REMAINDER OF THE AREA...

A 1009 mb low along the monsoon trough is centered near 11N115W.
Scattered moderate isolated strong convection is noted from 09N
to 12N between 115W and 119W. An earlier ASCAT pass showed 
strong SW to W winds from 08N to 10N along with seas of 9-10 ft. 
Development, if any, of this system is expected to be slow to 
occur over the next day or two while the disturbance moves slowly
westward. By early next week, environmental conditions are 
forecast to become less conducive for further development. There 
is a low chance of tropical cyclone development within the next 
48 hours.

A surface trough extends southward from a large low pressure 
system north of the area to 30N130W to 26N134W. Earlier ASCAT 
data showed mostly fresh southwest winds north of 28N between 
123W and 135W. Large seas of 8-11 ft in NW to N swell are 
ongoing north of 26N and west of 123W. Seas are 8 to 10 ft in NW
to N swell from the Equator to 17N between 110W and 140W.
Elsewhere, a surface trough extends from near 23N120W to 
15N122W. Isolated showers are near the trough. Moderate to fresh
N winds are W of the trough to near 128W. Seas are 8-10 ft in 
the vicinity of the through due to long-period NW swell. South of
the monsoon trough to 03N, and E of 105W, moderate to fresh SW 
winds prevail with seas 7-10 ft in mixed S and NW swell.

For the forecast, the large NW to N swell covering the area south
of 17N and west of 110W will subside Sat night as it continues 
to spread southward. The fresh winds north of 28N will diminish
tonight. NE trade winds will increase to fresh late Sat through 
Sun night across the entire area north of the monsoon 
trough/ITCZ as high pressure builds back across the region. Winds
will diminish late Mon. Large northerly swell will affect waters
north of 20N and east of 130W Sun night through Mon night before
gradually subsiding mid-week.

$$
Hagen