000
AXPZ20 KNHC 180946
TWDEP 

Tropical Weather Discussion 
NWS National Hurricane Center Miami FL
1005 UTC Thu Aug 18 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 0600 UTC surface analysis and satellite imagery through
0945 UTC.
  
...SPECIAL FEATURE... 

A tropical wave extends n to s from 10N109W to 13N109W with an
embedded 1006 mb low pressure along the wave axis near 16N109W.
This system have been moving northwest at 10 kt. Easterly shear
is limiting convection to a single cluster of scattered moderate
isolated strong within 30 nm of 16N110W. The upper wind shear is
forecast to weaken and this low has a medium probability
of tropical cyclone formation with the next 48 hours. Currently 
strong winds are observed within 180 nm se of the low level
center with seas 8 ft or greater within 330 nm over the se
semicircle of the center. The surface low is currently forecast
to reach near 18N111W late tonight, near 19N112W late Fri night,
near 21N114.5W late Sat night and near 21.5N117W late Mon night.

...TROPICAL WAVES...

A tropical wave axis is analyzed n of 09N along 91.5W, and is moving
w at about 15 kt. Clusters of scattered moderate to isolated strong
convection are noted within 60 nm of 14N91W and 13N95W. 

A tropical wave is analyzed from 11N132W to 19N132W with a 1008
mb surface low along the wave axis at 15.5N132W. There is no
significant convection at the moment, associated winds have
diminished to 20 kt or less and seas have subsided to less than
8 ft. Expect this system to move w of 140W in about 24 hours.

.INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 

The monsoon trough axis extends from 08N77W to 10N86W to 09N95W
to 13N102W...the resumes at 15N111W to 12N119W to beyond 11N140W.
Isolated moderate to strong convection is observed s of the
monsoon trough axis within 90 nm either side of a line from
06N77W to 10N87W, and along the monsoon trough within 30 nm
either side of a line from 12.5N111W to 11N118W.

...DISCUSSION...   

N of 15N e of 120W:

A surface ridge extends into the area from 27N120W to 27N117W,
and will gradually weaken late in the upcoming weekend as the
surface low previously described in the special features section
continues northwestward. A nnw to sse orientated trough will
meander e and w over the Baja California Peninsula, and the
northern Gulf of California for the next few days. 

A narrow band of fresh se winds, and 6-8 ft seas are observed
within 30 nm either side of a line from 16N101W to 18N103W.
These winds are forecast to diminish today with the associated
seas subsiding to less than 8 ft as well.

Strong northerly flow is expected across the Gulf of Tehuantepec
through sunrise this morning, then fresh nocturnal flow expected
through the upcoming weekend.

S of 15N e of 120W: 

Moderate to locally fresh ne-e winds are expected across, and
just downstream of the Gulf of Papagayo through mid morning
today, and then expected to develop again tonight.


W of 120W:

A surface ridge extends into the area from 32N136W to beyond
27N120W. Moderate to fresh anticyclonic flow is observed s 
of the ridge and n of the monsoon trough. Gentle to moderate
southerly flow is observed s of the monsoon trough.
  
$$
Nelson