000
AXPZ20 KNHC 130935
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Mon Nov 13 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 
0900 UTC.

...SPECIAL FEATURES...

A gale warning remains in effect for the Gulf of Tehuantepec, 
but confirmation from scatterometer data is more than 30 hours 
old. A ridge along the Sierra Madre Oriental combined with low 
pressure in the SW Caribbean is maintaining a tight pressure 
gradient across the Isthmus of Tehuantepec. Model guidance 
suggests that the current synoptic pattern will remain favorable 
for very strong gap wind flow through Tue night, with peak winds 
between 35 and 40 kt through Mon night. Max sea heights will be 
12 to 16 feet, then subside slowly Tue. The gap wind event will 
wind down Wed as the ridging shifts E into the Gulf of Mexico.

Scatterometer data at 0524 UTC indicated a low centered near 
16N127W with 25-30 kt winds north of the low center, and light 
winds south of the center. Satellite imagery shows an elongated 
cloud pattern with a mid-level circulation moving northward away 
from the surface low in strongly sheared conditions. Scattered 
moderate convection is from 10N to 23N between 121W and 129W. 
Global model guidance indicates this system has medium short-
term potential for tropical cyclone development today. Please 
refer to the East Pacific Tropical Weather Outlook TWOEP for 
more details.

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

The monsoon trough extends from 10N84W to 07N96W to 07N116W to 
low pressure near 16N127W to 11N140W. Except for a large area of 
showers associated with the low, scattered moderate convection 
is within 60 nm of the trough axis between 93W and 115W.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Please refer to the Special Features section for information 
regarding the ongoing Gulf of Tehuantepec gale warning.

A ridge will dominate the waters W of Baja California the next 
several days. The surface pressure gradient W of Baja California 
will tighten slightly today as high pressure shifts closer to 
the coast, resulting in fresh to locally strong NW winds N of 
25N and seas building to near 8 ft over the open Pacific waters. 
NW winds over the Gulf of California during this corresponding 
time period will increase from light to moderate. Elsewhere, 
mainly light to gentle winds and seas of 4 to 5 ft will prevail 
through Wed night. A weakening cold front will will move across 
the northern Baja peninsula Fri.

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

Light and variable winds and seas of 4 to 6 ft are expected N of 
the monsoon trough, which will fluctuate between 07N and 10N 
through Wed. Moderate to locally fresh S to SW winds and seas of 
5 to 7 ft are forecast S of the monsoon trough through Tuesday. 
Stronger SW winds south of the monsoon trough will build seas to 
above 8 ft in the Gulf of Panama region Tuesday through Thursday.

REMAINDER OF THE AREA...

Low pressure centered near 16N127W is discussed above in special 
features section. The combination of decaying long period swell 
in NW waters and strong winds north of the low is maintaining 8 
to 13 ft seas from 12N to 21N between 123W and 134W. The area of 
high seas will diminish through Tue as the swell continues to 
decay and the low weakens in a hostile environment. A fresh set 
of 8 to 9 ft NW swell will reach NW waters tonight and Tuesday, 
then decay Wed. Elsewhere, light to moderate NE winds and seas 
of 5 to 7 ft seas will prevail through Friday.

$$
Mundell