000
AXPZ20 KNHC 120229
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Fri Aug 12 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 0000 UTC surface analysis and satellite imagery through
0200 UTC.
  
...TROPICAL WAVES...

A weak tropical wave extends from 15N101W to 09N102W. Moisture
has diminished in association with the wave. As a result, only
isolated showers are noted near the wave axis. The most recent
scatterometer pass indicated the wind shift associated with the
wave.

A better defined tropical wave is analyzed from 17N109W to
09N110W. Isolated moderate convection is seen on either side of
the wave axis roughly between 106W and 114W. The wave remains
embedded within an area of deep layered moisture as depicted on
the TPW animation and it shows up pretty well on the 700 mb
streamlines. Some cyclonic turning was also noted along the wave
axis on visible satellite imagery. Model diagnostics guidance
suggests that this wave will maintain definition at the surface
level while it tracks westward over the next couple of days. The
edge of an earlier scatterometer pass captured the wind shift
related to the wave axis.


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

Monsoon trough axis extends from 07N78W to 11N95W to 12N102W to
09N114W to low pressure near 15N122.5W 1009 MB to low pressure
near 13N126W 1010 MB to low pressure near 10N138W 1010 MB and to
beyond 10N140W. Scattered moderate isolated strong convection is
noted from 08N to 10N between 92W and 97W. Similar convection is
within 60 nm south of trough between 129W AND 131W.

...DISCUSSION... 

N of 15N E of 120W:

Cloudiness has diminished over the southern Baja California
peninsula compared with the previous days. Satellite imagery
shows an area of low and middle level clouds hugging the pacific
coast from 23N to 26N, and within about 150 nm west of that coast.
The most recent scatterometer data provided observations of
gentle to moderate southerly winds across the northern Gulf of
California, mainly N of 29N while NW winds in the 10-15 kt range
are noted along the pacific coast of Baja California. These winds
are on the east side of a ridge that extends across the north
waters.

S of 15N E of 120W:

Winds are now 20 kt or less across the Gulf of Papagayo, but a
small area of seas to 8 ft persist downstream of the gulf from 
10N to 11N between 89W and 91W. Seas are forecast to subside
below 8 ft later tonight.

A couple of tropical waves are moving across the area. Please
refer to the Tropical Waves section for details. 

W of 120W:

High pressure located NW of area extends a ridge across the north
waters to near the Revillagigedo Islands. The pressure gradient 
between the ridge and lower pressure near the monsoon trough is
generating moderate to fresh northeast winds to the north of 15N
and west of 120W with seas in the 5-7 ft range based on an
altimeter pass.

As previously mentioned, there are three areas of low pressure
along the Monsoon Trough. The first one is near 15N122.5W. A cluster
of moderate to isolated strong convection is within about 120 nm
west semicircle of low center. The second one is near 13N126W.
Scattered moderate convection is from 12N to 15N between 125W and 128W.
Marine guidance suggests a little increase in winds and seas on
the northern semicircle of this low by Friday evening as it continues
to move westward over the next couple of days. The third low is
near 10N138W. A swirl of low clouds is associated with this system.

$$
GR