000
AXPZ20 KNHC 080230
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Thu Sep 08 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
0230 UTC.
  
...TROPICAL WAVES...

The axis of a tropical wave extends N from 06N105W TO 18N104W
and has been moving w at about 12 kt. Scattered moderate
isolated strong convection is currently observed to the s of 15N
within about 300 nm either side of the wave axis. A surface low
is forecast to develop along the wave near 09N109W late Thu and
move w to near 09N114W late Fri. Model guidance suggests that
environmental conditions will become favorable for tropical
cyclone formation in 3 to 5 days.

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

The monsoon trough axis extends w from the Pacific coast of
Costa Rica at 10N85W to 10N90W TO...then dips sw through the
tropical wave to 08N105W...then turns abruptly TO 16N118W..then
turns sw through an ill-defined 1010 mb low pres near
16N120W...then continues sw through a 1009 mb low pres at
12N137W and continues w to beyond 12N140W.

Except as already described near the tropical wave, scattered
moderate isolated strong convection is observed from 06N to 14N
between 94W and 110W, and within 150 nm either side of a line
from 15N117W to 11N130W to 10N140W.

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

A sub-tropical ridge axis extends from nw to se across the
western portion of offshore zones w of the Baja Peninsula.
Gentle to moderate nw flow is expected through the weekend. 

A thermal trough will soon develop over the Baja Peninsula and
across the northern Gulf of California. This will maintain light
and variable flow across the Gulf of California through the
weekend, except increasing to a moderate to occasionally sw flow
between 30N and 31.5N during the late night hours. 

Fresh northerly drainage flow is forecast across, and just
downstream of the Gulf of Tehuantepec during the overnight
hours, except increasing to strong briefly tonight and Thu
night with seas building briefly to 9 ft.  

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

Light and variable winds forecast to the n of about 05N through
the period, while moderate sw to w flow is expected across the
EPAC waters generally to the s of 05N. Forecast combined seas of
4 to 7 ft across the entire waters through the period primarily
in mixing long-period sw and swell.

REMAINDER OF THE AREA...

Except as previously mentioned in the tropical wave section, a
quasi-stationary surface ridge will extend from near 32N138W to
near 24N118W.  Moderate ne flow will continue through the
weekend to the s of the ridge and n of the monsoon trough, with
combined seas of 4 to 6 ft. 

Fresh ne winds with combined seas of 7 to 9 ft are observed n of
27N w of 125W through Thu. The gradient will then relax with a
weak trough shifting w across the waters n of 25N over the
weekend with a surface high pressure developing e of the trough
near 28N125W on Sat.    

$$
Nelson