000
AXPZ20 KNHC 111552
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1236 UTC Mon Sep 11 2017

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 1200 UTC surface analysis and satellite imagery through
1500 UTC.
  
...TROPICAL WAVES...

The axis of a tropical wave is near 110W from 05N to 21N, with
low pressure noted near 16.5N110W. Scattered moderate isolated 
strong convection is noted within 180 nm west of the wave axis 
from 12N to 19N. 

INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 

The monsoon trough extends from 14N91W to 14N99W to 16N109W to
12N121W to 12N134W to 10N140W. Scattered moderate isolated 
strong convection is noted within 180 nm either side of a line 
from 08N84W to 10N110W. Scattered moderate convection is noted
within 60 nm of the monsoon trough between 126W and 135W. 

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

A NW to SE oriented trough will meander across the Baja 
California Peninsula and the Gulf of California with a surface 
low developing intermittently along the trough axis over the far 
northern Gulf waters. A W to E orientated ridge will meander 
from 23N116W to 21N110W early this week with a moderate W to NW 
breeze is forecast across the EPAC waters S and W of the Baja 
California Peninsula through Wed afternoon, with 5 to 6 ft seas.

Gulf of Tehuantepec: Strong to near gale force northerly flow is 
expected through early Tue, with seas building to 11 ft 
downstream of the gulf waters near 14.5N95.5W.
  
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND 
WITHIN 750 NM OF ECUADOR...
    
The monsoon trough has lifted N, with moderate to locally fresh 
southwesterly monsoonal flow expected S of the trough axis
expected the next several days. Seas in the 6 to 9 ft range in 
cross- equatorial southerly swell prevails. These southerly 
swells will begin to subside on Tue night, with seas expected to 
fall below 8 ft by Fri night.

REMAINDER OF THE AREA...

High pressure of 1024 mb centered north of the area near 38N137W
extends a ridge to 27N132W to near 21N114W. Moderate anticyclonic
flow is expected N of the monsoon trough and W of 115W.

Fresh to locally strong SW monsoonal flow, and 8 to 12 ft seas, 
is forecast from 06N to 10N between 97W and 110W today in long 
period cross- equatorial swell. This swell will begin to subside 
on Tue night.
  
$$
AL