000
AXPZ20 KNHC 212143
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2143 UTC Wed Sep 21 2016

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 1800 UTC surface analysis and satellite imagery through
2100 UTC.

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

The monsoon trough axis extends from 10N86W to 09N93W TO 12N105W
to low pres near 10N116W 1011 mb to 15N124W to low pres near
12N138W 1012 mb to 11N140W. Scattered moderate convection is
within 150 nm south of the axis between 98W and 101W. Scattered
moderate to isolated strong convection is within 180 nm north of
axis between 110W and 116W. Scattered moderate convection is
within 120 nm south of the monsoon trough axis between 123W and
133W, and within 60 nm south of axis west of 137W.

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

A scatterometer pass from 17 UTC showed no strong winds near the
remnant low of what was tropical cyclone Paine off the coast of
Baja California Norte, but instead showed 15 to 20 kt over the far
northern portion of the Gulf of California. Seas may still be
reaching 8 ft between Punta Eugenia and Guadalupe Island but will
subside through late this evening. Northerly swell to 9 ft will
propagate as far south as 25N before subsiding.

Farther south, strong gap winds into the Gulf of Tehuantepec have
likely diminished this morning, but a brief pulse may again occur
late this evening.

Looking ahead, there is better agreement among
global models concerning the development and track of low pressure
currently well to the south along the monsoon trough. The low will
gradually deepen as it tracks north, nearing Clarion Island by
Sunday. Prior to the low undergoing further development, a broad area of
south to southwest winds with seas roughly in the range of 8 to 10
ft will exist to the east and southeast of the low.

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

Moderate to occasionally fresh winds will prevail N of the
monsoon trough, while gentle to moderate SW winds are expected
south of the monsoon trough. Seas of 4 to 6 ft will prevail
through tonight, then build to near 7 ft Thursday and Friday as
long period southwest swell propagate into the region. Seas will
begin to subside on Saturday.

REMAINDER OF THE AREA... 

1012 mb low pressure along the monsoon trough near 12N138W will
shift west of the area in the next 24 hours. Meanwhile, a surface
ridge extends from a 1031 mb high center well north of the area
near 39N138W southeastward to 20N120W. The pressure gradient
between the ridge and lower pressure farther south along the
monsoon trough is supporting mainly gentle to moderate trades with
local areas of fresh trades south of 20N and west 125W. Seas in
this area continue to range between 5 and 7 ft.

$$
CHRISTENSEN