000
AXPZ20 KNHC 100925
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Wed Jan 10 2018

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 
0900 UTC.

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

A surface trough extends from 09N83W to 04N94W. The ITCZ 
continues from 04N94W to 08N126W to 09N140W. No significant 
convection is noted.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Gulf of Tehuantepec: A gale warning is no longer in effect. The 
pressure gradient across the Isthmus of Tehuantepec is relaxing 
as a ridge in the western Gulf of Mexico weakens. Winds are 
expected to rapidly diminish today. Seas to 9 ft early this 
morning will subside to 5-6 ft this afternoon. Looking ahead, a 
much stronger gap wind event is projected to begin Fri morning, 
then could peak at storm force on Sun, and continue into Tue.

A cold front moving into northern Baja California extends from 
30N113W to 23N118W to 19N128W. Fresh to locally strong SW to W 
winds are occurring N of 30N in the Gulf of California, with 
seas to 6-7 ft. Winds on the Pacific side of the Baja peninsula 
are moderate to fresh on either side of the front, and large 
seas to 13-15 ft are located west of the front, highest north of 
26N. The front will sweep across Baja California and the Gulf of 
California today. Fresh winds will continue ahead of the front 
until midday. Fresh gap winds are also anticipated behind the 
front over the northern Gulf of California south of San Felipe. 
The large NW swell will gradually decay off Baja California 
through Thu, and subside as they reach the Revillagigedo Islands 
Thu evening. Strong high pressure building over the U.S. Great 
Basin could generate strong NW winds over the central portion of 
the Gulf of California Thu night and Fri, with seas peaking at 
around 8 ft Fri morning near 26N.

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

A weak pressure gradient over central America is maintaining 
moderate to fresh gap winds over the Gulf of Papagayo. Strong 
winds are expected to redevelop there Sat morning as high pres 
builds over the western Caribbean. Winds could reach near gale 
force on Sun. Seas expected to develop from the Gulf of Papagayo 
will merge with the area of seas south of Tehuantepec on Sun.

Elsewhere, light to moderate SW winds will persist S of Costa 
Rica and Panama. Seas will remain generally between 3 and 5 ft. 
Expect scattered nocturnal showers and thunderstorms south of 
Panama through Wed night. N winds over the Gulf of Panama could 
become fresh by Mon morning.

REMAINDER OF THE AREA...

As noted above, a cold front extends across the forecast waters 
from 30N113W to to 23N118W to 19N128W. Scatterometer data from 
around 05Z showed 25 kt winds off the California coast near 32N. 
Long period NW swell generated by strong winds behind the front 
will cause seas to build in excess of 8 ft north of 20N and west 
of 115W by Thu morning. This area of seas will slowly decay on 
Fri and Sat. A cold front approaching 30N140W Sun will generate 
more large long period NW swell, that could build to 20 ft in 
far northwest waters by Sun evening.

$$
Mundell