000
AXPZ20 KNHC 300103
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 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 0000 UTC surface analysis and satellite imagery through
0215 UTC.

...SPECIAL FEATURES...

A significant swell event that will produce heavy surf conditions
has reached the offshore forecast waters of Baja California. The
leading edge of a swell train, with periods of 19 to 22 seconds,
is reaching the Revillagigedo Islands, with seas of 8 to 11 ft. 
This will bring large breaking waves of 20 ft and higher along 
the coast of Baja California Peninsula through Monday. Some of 
the swell energy could refract into the southern Gulf of 
California late tonight and Monday. Expect for the swell energy 
to bring rough surf conditions to those coasts. 

INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 

The monsoon trough extends from a 1010 mb low pressure near
11N91W to another 1010 mb low pressure near 12N102W to 12N115W 
to 10N130W to 07N135W, where it transitions to the ITCZ and 
continues beyond 07N140W. Scattered moderate convection is within
75 nm NW quadrant of low near 11N91W. Similar convection can be 
found N of 14N between 97W and 103W, within 90 nm NE quadrant of 
low near 12N102W, and from 08N to 10N between 115W and 117W. 
Isolated moderate convection is from 07N to 12N between 120W and 
133W. 
 
...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: The most recent scatterometer pass shows
northerly winds of 20 to 25 kt in and downwind of the Gulf of 
Tehuantepec to near 13N96W. Seas are in the 8 to 10 ft range.
Winds will increase to 25 to 30 kt tonight into the early morning
hours with the assistance of the nocturnal drainage flow. Then 
winds are forecast to diminish to 20 kt or less by Monday 
afternoon. Another Tehuantepec gap wind event is expected toward
the end of the work week.

Gulf of California: A developing low pressure over the northern 
gulf will bring moderate to fresh southerly winds over the gulf 
waters N of 29N tonight through Monday night. Gentle to moderate
southerly winds are expected elsewhere.

A ridge dominates the offshore waters of Baja California producing
gentle to moderade NW winds. Little change is expected through 
Monday night. On Tuesday, winds will turn light to gentle as a 
weak trough develops over the NE forecast waters between the 
coast of Baja and 120W. By that time, seas will be in the 4 to 6 
ft range.

OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND 
WITHIN 750 NM OF ECUADOR...
    
A small area of low pressure located a couple of hundred miles south
of the coast of Guatemala is producing disorganized showers and
thunderstorms. Latest satellite imagery indicates that convection
is limited and the low center is totally exposed. Slow development
of this system is possible during the next several days while 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 moonsoon trough, with seas generally of 
4 to 5 ft.
 
REMAINDER OF THE AREA...

A significant swell event is affecting the forecast waters NW of
a line from 30N116W to 20N112W to 10N125W to 00N135W. Several 
altimeter passes across this area indicate seas of 8 to 12 ft.
This swell event will continue to propagate SE to cover most of 
the waters W of 110W by tonight, and W of 110W by Monday night. 
Conditions will gradually improve over the northern waters Monday
into Tuesday as the large swell decay and propagate into the 
southern waters. The swell over the southern waters will continue
to decay and allow seas in this area to diminish below 8 ft by 
midweek.

A 1021 mb high pressure located near 29N133W extends a ridge
across the forecast waters N of 17N W of 120W. A gentle to
moderate anticyclonic wind flow is noted under the influence of
the ridge, forecast to persist across the region over the next
couple of days. A weak cold front is expected to reach the NW 
corner of the forecast area on Wednesday with little impact in 
winds and seas.
  
$$
GR