000
AXPZ20 KNHC 090320
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Mon Jan 9 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
0300 UTC.

...SPECIAL FEATURES...

Gulf of Tehuantepec Storm Warning: High pressure centered over
eastern coastal Mexico extends a ridge southward toward the
isthmus of Tehuantepec. The strong pressure gradient between the
area of high pressure and low pressure within the monsoon trough
is supporting storm force winds in the Gulf of Tehuantepec with
seas to 24 ft, based on recent ship reports and altimeter data.
The high will shift eastward later tonight, which will allow the
pressure gradient to gradually relax, with max winds diminishing
below storm force overnight. Gale force winds are expected to
continue another day or so through Tuesday night. A large area
of NE swell generated by this high wind event will spread far
from its source region west to 110W, and south of the equator.

Gulf of Papagayo Gale Warning: The pressure gradient associated
with high pressure extending from the northwest Caribbean across
interior Central America will tighten overnight and winds in the
Gulf of Papagayo region will increase to minimal gale force late
tonight. Gales are expected to persist through this morning then
remain near gale through Tuesday morning, then become fresh to
strong through Thursday. Seas will build to 11-13 ft later today
and remain 9-12 ft downwind from the Papagayo gap into Tuesday.

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

The monsoon trough axis extends from 05N77W to 04N105W. The ITCZ
axis continues from 04N105W to 08N118W to low pressure near
08N133W to 08N140W. Scattered moderate convection is from 08N to
11N between 125W and 130W.

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Please see special features section for more details on the Gulf
of Tehuantepec high wind event. 

A weak pressure gradient prevails over much of the remaining
forecast region. Light to gentle winds with 3-5 ft seas prevail
off the coast of the Baja California peninsula and along the
southwest coast of Mexico. Northwest swell will propagate into
the waters offshore of Baja California Norte Wednesday night,
increasing seas to 10 ft by early Thursday morning.
  
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...

Please see special features section for more details on the Gulf
of Papagayo high wind event.

A tight pressure gradient across Central America will support
fresh to strong northeast winds northwest of Nicaragua including
the Gulf of Fonseca through Tuesday.

In the Gulf of Panama and near the Azuero Peninsula, northerly
winds are expected to increase to 20-25 kt overnight as strong
winds funnel into the area from the southwest Caribbean, and
remain fresh to strong through Tuesday. Seas will build to 8-10
ft south of the peninsula by early Tuesday.

The combined swell generated from the Gulf of Papagayo and Gulf
of Tehuantepec gap wind events will generate a large area of 8
ft or greater seas that will extend from the Tehuantepec and
Papagayo regions southward to near the equator and westward to
near 115W by early Tuesday.

REMAINDER OF THE AREA...

1010 mb low pressure area embedded in the ITCZ near 08N133W is
moving west around 15 to 20 kt. Persistent deep convection is
located within 150 nm of the low center. Previous scatterometer
passes showed fresh to strong NE winds north of the low, and
recent altimeter passes and a buoy near 10N125W measured 8-9 ft
seas. This low will move west of 140W during the next 24 hours.

A large occluded low pressure system north of the area extends a
cold front through 30N128W to 20N138W. A weak ridge extends from
28N121W to 21N128W. The pressure gradient between these two
features is supporting fresh SW winds north of 28N within 60 nm
east of the front. The front will move across northern waters
during the next couple of days, and dissipate with associated
seas diminishing as well. The low pressure area well north of
the area will continue to generate pulses of moderate to large
northwest swell which will propagate into the northwest waters
with seas building above 8 ft by Tuesday.

The combination of swell generated from the Gulf of Papagayo and
Gulf of Tehuantepec gap wind events will generate a large area
of high seas that will eventually extend from the Tehuantepec
and Papagayo regions southward to near the equator and westward
to near 115W by Monday night.

Elsewhere, gentle to moderate trades are forecast to prevail over
most of the area under a weak pressure gradient through the middle
of next week.

$$
Mundell