000
AXPZ20 KNHC 252204
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2147 UTC Mon Dec 25 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 1800 UTC surface analysis and satellite imagery through
1800 UTC.

..SPECIAL FEATURES...

Gulf of Tehuantepec Gale Warning: A high pressure ridge 
extending south from Texas to the Sierra Madre Oriental range 
is maintaining a gap wind event over the Gulf of Tehuantepec. No
observations have been available today in the area. However, it
is likely that peak winds are at gale force winds. The high
pressure ridge will only gradually fade and the gale conditions
should be dropped by Tuesday afternoon. The gap wind event will
continue for the next several days and may again reach gale force
early Saturday morning when a new cold front in the Gulf of
Mexico reaches the Chivela Pass in southern Mexico. Peak
significant wave heights should be around 13 feet late night. 
Please refer to the latest high seas forecast issued under 
AWIPS/WMO headers HSFEP2/FZPN03 for more details.

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

A trough extends from a 1009 mb low at 06N79W to 06N95w. The ITCZ
extends from 06N95W to 09N110W to 08N133W to beyond 10N140W.
Isolated moderate convection is occurring within 120 nm south of
the ITCZ between 100W and 125W.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Please refer to the special features section above for details 
on the ongoing Gulf of Tehuantepec Gale event. 

Elsewhere, mainly gentle to moderate winds with benign marine 
conditions are expected through Thursday. NW swell bringing 
seas in the range of 6 to 8 ft generated by strong winds off the
coast of California could enter the far NW offshore waters of 
Baja California Norte on Tuesday. Low pressure over interior 
Mexico could combine with high pressure NW of the area to 
generate fresh to strong winds between Cabo San Lucas and Cabo 
Corrientes on Friday afternoon and evening.

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

Strong gap winds over the Gulf of Papagayo will continue pulsing
through Friday night, with the broadest extent of the winds 
occurring tonight and Tuesday night. Seas will peak between 8 
and 9 ft during this time frame. NE swell producing seas to 9 ft
will impact some portions of the offshore waters of Guatemala 
through late tonight as swell originating from the Gulf of 
Tehuantepec gap wind event propagates S and SW through the
offshore waters. Otherwise, gentle to moderate winds and seas of
5 to 7 ft can be expected through Friday.


REMAINDER OF THE AREA...

A trough over the NW corner of the area extends from 32N135W to 
24N140W. The trough will weaken as it moves to the W of the 
area through Wednesday. Fresh to strong S winds that were 
formerly present N of 27N and up to 120 nm east of the front have
subsided. Residual NW swell of 8 to 11 ft generated to the NW of
this boundary earlier will slowly propagate SE and disperse 
through Wednesday as seas W of 120W and N of 10N subside to 
around 8 ft. A reinforcing set of NW swell will maintain sea 
heights between 8 and 9 ft N of 20N and W of 130W on Wednesday 
and Wednesday night. Forecast models are also hinting at 
increasing winds late Tuesday and Wednesday as the pressure 
gradient tightens between the aforementioned trough currently 
extending from 32N135W to 24N140W and high pressure building to 
its N and NE. Winds in the vicinity of the trough are currently 
forecast to reach fresh speeds Tuesday night through Thursday. 
The combination of the wind waves and NW swell is expected to 
produce seas to between 8 and 9 ft in this area.

Elsewhere, moderate to fresh winds will prevail as seas generally
run between 6 and 8 ft.

$$
Landsea/Aguirre