000
AXPZ20 KNHC 102134
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2020 UTC Wed Aug 10 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.
  
...TROPICAL WAVES...

A weak tropical wave extends from Guatemala near 15N90W to 07N91W
moving west at 10 to 15 kt. Scattered moderate convection is seen
from 09N-12N west of the wave axis to 94W. Similar convection is
also noted where the wave meets the Monsoon Trough. The wave is
embedded in an area of abundant moisture as noted in SSMI TPW
imagery and a weak inverted trough is observed in 700 mb
streamlines.

A better defined tropical wave is analyzed from 15N102W to 08N102W.
No significant convection is associated with this wave at this
time. Model guidance indicates that this wave will maintain a
rather well-defined northeast to southeast wind shift across its
axis as it continues westward over the next 24 to 48 hours.

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

Monsoon trough axis extends from 08N79W to 09N87W to 08N91W to 09N102W
to 10N110W to 1009 mb low pressure center near 14N119W to another 1010
mb low pressure near 11N131W to 09N140W. Scattered moderate to
isolated strong convection is within 150 nm south of the axis east
of 81W. Similar convection is seen within 120-150 nm south of
axis between 84W and 97W, and from 08N-13N between 130W-135W.

...DISCUSSION... 

N of 15N E of 120W:

A trough extends along the Baja California peninsula from 33N116W
to 27N112W to 23N112W. Isolated showers are possible within 90 nm
of the trough. The pressure gradient between the trough and
relatively higher pressure near it is allowing for fresh to
locally strong southeast to south winds over the far northern
portion of the Gulf of California. These winds are forecast to
diminish to 15-20 kt by early this evening.

Moisture partially related to Javier has spread into Arizona and
New Mexico, where 2 to 4 inches of rain, with isolated amounts of
up to 8 inches, are possible through Thursday. 

S of 15N E of 120W:

Expect pulsing winds, in the 20-25 kt range, and seas building as
high as 8 ft in the Gulf of Papagayo again late tonight before
diminishing to 15-20 kt Thursday afternoon and seas lowering 
to 5-6 ft.

A couple of tropical waves are moving across the area. Please
refer to the Tropical Waves section for details. Satellite imagery
depicts that the Monsoon Trough is very active east of 100W.

W of 120W:

A ridge dominates the forecast waters north of 15N and west of
120W. The pressure gradient between the ridge and lower pressures
near the Monsoon Trough is generating moderate to fresh
northeasterly winds to the north of 15N and west of 125W based on
recent scatterometer passes. A couple of altimeter passes indicate
that sea heights within this area continue to be in the 5-7 ft
range.

A short-lived long-period north swell is producing seas up to 8
ft north of 29N between 123W and 128W. This swell event is
forecast to decay by late tonight with seas subsiding to less than
8 ft.

A weak area of low pressure about 850 miles southwest of the
southern tip of the Baja California peninsula is drifting
northwestward.  The low is forecast to merge with an area of
disturbed weather farther west later this week, and some slow
development of that system is possible by the weekend while it
moves generally westward. The Tropical Weather Outlook from 11 am 
PDT indicates a low chance of formation during the next 5 days.

Of note, after a very active period of tropical cyclone formation
in the Eastern Pacific region with 5 tropical storms and 5
hurricanes from July 2nd to August 9th, today weather conditions
are quieter.

$$
GR/ERA