000
AXPZ20 KNHC 300912
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
646 UTC Mon Oct 30 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 0600 UTC surface analysis and satellite imagery through
0830 UTC.

...SPECIAL FEATURES...

The significant swell event currently producing heavy surf 
conditions has peaked but continues in the offshore forecast 
waters of Baja California. The leading edge of the swell train, 
with periods of 19 to 22 seconds, is reaching the southern tip of
the Baja Peninsula and the Revillagigedo Islands, with seas of 8
to 10 ft. This will maintain large breaking waves of 15 to 20 ft
along the coast of Baja California Peninsula today. Some of the 
swell energy could refract into the southern Gulf of California 
today. Expect this swell energy to maintain rough surf conditions
on Pacific exposures before surf heights subside tonight.

INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 

The monsoon trough extends from 10N74W to 1010 mb low pressure
centered near 11N90.5W to 12N102W to 10N114W to 12N115W to 
10N127W, where it transitions to the ITCZ. The ITCZ continues
from 10N127W to beyond 09N140W. Scattered moderate and isolated
strong convection is present from 09N to 15N between 100W and 
104W and from 09N to 12N between 117W and 124W.
 
...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Significant swell event: please refer to the Special Features 
section above for information on swell affecting the Pacific 
coast of Mexico through Monday.

Gulf of Tehuantepec: Winds and seas continue to subside as high 
pressure over the western Gulf of Mexico and along the slopes of 
the Sierra Madre Oriental shifts eastward and weakens. Strong 
winds over the Gulf of Tehuantepec are forecast to diminish to 20
kt or less by this afternoon. Strong to near gale force winds 
could affect the Gulf of Tehuantepec from Friday night through 
early next week.

Gulf of California: Developing low pressure over SE California 
and surface troughing over Baja California Norte will generate 
fresh to strong S to SW winds over the gulf waters N of 29.5N 
this afternoon through tonight. Otherwise, gentle to moderate S 
to SW winds are expected through Tue night.

A weak ridge extending into the offshore waters of Baja 
California will produce light to gentle NW winds through Wed. 
Seas of 6 to 9 ft today will subside to between 4 and 6 ft by 
Wed.

OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND 
WITHIN 750 NM OF ECUADOR...
    
A small area of low pressure is centered about 150 miles south 
of the coast of Guatemala has very little convection associated 
with it. Some slow development of this system is possible during
the next several days as it moves westward to west- 
northwestward. Elsewhere, expect light westerly winds N of the 
monsoon trough, and gentle to moderate S to SW winds south of the
monsoon trough, with seas generally running between 4 to 6 ft.
 
REMAINDER OF THE AREA...

A significant swell event continues in the forecast waters N of 
a line from 20N112W to 07N116W to 10N125W to 00N140W. Satellite- 
derived sea height data from the past 12 hours indicate seas of 8
to 10 ft in this area. Swells in this area will continue to 
propagate SE but continue to decay, allowing the areal coverage 
of 8 ft seas to decrease. Conditions will gradually improve over 
the northern waters through Tuesday as the large swell decay and 
propagate into the southern waters. The swell in the southern 
waters will continue to decay as well and allow seas in this area
to diminish below 8 ft by midweek.

A ridge resides over the forecast waters N of 17N W of 120W. A 
gentle to moderate anticyclonic wind flow is noted on the 
southern flank of the ridge. This synoptic setup is forecast to 
continue over this area through Wed. A weak cold front is 
expected to reach the NW corner of the forecast area on 
Wednesday, but produce little impact in either winds or seas. The
front is forecast to move slowly SE across the NW waters and 
weaken through Friday.
  
$$
CAM