000
AXPZ20 KNHC 120322
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Sat Nov 12 2016

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
0300 UTC.

...SPECIAL FEATURES...
A gale warning remains in effect for the Gulf of Tehuantepec. The
pressure gradient between high pressure over eastern Mexico and
low pressure within the monsoon trough over the eastern North
Pacific will support minimal gale force winds over the Gulf of
Tehuantepec tonight into Saturday morning, and Saturday night into
Sunday morning. Then, fresh to strong northerly winds, in the
25-30 kt range, will continue to surge into the Gulf of Tehuantepec
through Monday. A reinforcing cold front will shift across the
Gulf of Mexico early next week. This will result in a stronger
gale force gap wind event over the Gulf of Tehuantepec early next
week.

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

The monsoon trough extends from 09N84W to 1011 mb low pressure
near 08N89W to 08N100W to 1008 mb low pres near 14N110W to 10N115W
to 1010 mb low pressure near 13N124W to beyond 09N140W. Cluster of
moderate to strong convection N of 06N E of 80W...including the Gulf
of Panama. Scattered moderate isolated strong convection can be
found from 04N to 08N between 80W and 86W, and within 45 nm of
the coast of Costa Rica. Similar convection is from 06N to 09N
between 95W and 98W, from 13N to 16N between 102W and 104W, from
09N to 11N between 112W and 116W, and within 120 nm S of trough W
of 135W.

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Please see special features section above for more on the Gulf of
Tehuantepec gale force gap wind event. 

Gentle to moderate northerly winds are expected across the Gulf of
California with seas generally under 3 ft. Moderate to fresh
northerly winds are forecast across the northern part of the
Gulf, mainly N of 30N Sunday morning and Monday morning. The
pressure gradient between a trough over western Mexico and a ridge
across the waters W of Baja California will support this slight
increase in winds.

Seas will slightly diminish across the waters west of Baja
California tonight before a fresh set of large northwesterly
swell propagates into the area. Seas associated to this swell
event will reach 8-10 ft over the open waters off the coast of
Baja California Sunday into early next week before subsiding below
8 ft by Tuesday. A low pressure system moving into the waters off
southwest Mexico is forecast to increase winds and seas across the
offshore waters S of 20N this weekend.

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

Winds will pulse the next several days over the Gulf of Papagayo.
Winds will peak near 15 to 20 kt during the late night and early
morning hours, with seas building to 5-6 ft downstream of the Gulf
of Papagayo. Elsewhere, light to gentle winds will prevail over
the waters north of 10N, with gentle to moderate mainly southwest
winds south of 10N. Seas of 4 to 6 ft will prevail across the
region.

REMAINDER OF THE AREA...

A cold front is over the NW waters and extends from 30N131W to 
23N140W. The front is forecast to move SE reaching from 30N129W
to 25N140W by early Saturday afternoon while dissipating. Ahead of
the front, a 1019 mb high pressure is centered near 27N131W. The
pressure gradient between this area of high pressure and lower
pressure within the monsoon trough is supporting moderate trade
winds north of the monsoon trough to 17N as depicted in the latest
ASCAT passes. This high pressure is forecast to dissipate in about
24 hours. Then, high pressure in the wake of the front will take
control of the weather pattern across the north forecast waters.

A low pressure of 1008 mb centered near 14N110W is embedded
within the monsoon trough. This system has become better defined
since yesterday. However, shower and thunderstorm activity
associated with the low remains disorganized due to strong upper-
level winds. Although some further increase in organization of
this system is possible during the next 12 to 24 hours, even
stronger upper-level winds are likely to preclude tropical cyclone
formation as the low moves north-northeastward. Regardless of
tropical cyclone formation, locally heavy rainfall is possible
over portions of southwestern and central Mexico during the next
couple of days in association with this disturbance. Fresh to
strong winds, with seas of 8 to 12 ft are expected mainly on the
E semicircle of the low center this weekend.

A new set of long period NW swell, with significant wave heights
as high of 15-16 ft is propagating across the NW waters behind the
cold front previously mentioned. This swell will cover the waters
much of the waters N of 10N W of 115W by early Sunday morning, and
much of the waters W of 110W by early Monday morning. This swell
event will continue to propagate southeastward while subsiding
through the middle of next week.

$$
GR