000
AXPZ20 KNHC 092140
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 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 1800 UTC surface analysis and satellite imagery through
2100 UTC.

...SPECIAL FEATURES...

Gulf of Tehuantepec Gale Warning: Strong high pressure over
eastern Mexico combined with low pressure south of the area near
the monsoon trough continues to support strong gale force winds
offshore across the Gulf of Tehuantepec. Seas are up to around
20 ft at this time. A large area of NE swell generated by this
gap wind event will propagate far from its source region west to
120W, and south of the equator over the next couple of days. The
pressure gradient will gradually relax through Tuesday night
with gale force winds diminishing by early Wednesday. Nocturnal
northerly flow will then pulse to fresh to strong thereafter.

Gulf of Papagayo Gale Warning: A tight pressure gradient between
high pressure centered north of the area and low pressure within
the monsoon trough has increased winds funneling into the Gulf
of Papagayo. Aided by nocturnal drainage flow, these gap winds
may reach minimal gale force over the Gulf of Papagayo tonight
into early Tuesday. Winds are then expected to diminish below
gale force Tuesday afternoon. Seas are 11-13 ft downwind of the
gulf. Gap winds will pulse to near gale force Tuesday night, and
then fresh to strong thereafter, with strongest winds expected
during overnight and early morning hours.

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

The monsoon trough extends from 06N77W to 05N84W to 04N98W. The
ITCZ axis continues from 04N98W to 06N110W to 06N130W to
08N140W. Scattered moderate isolated strong convection is north
of 02N east of 80W. Scattered moderate convection is from 09N to
11N between 128W and 134W.

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

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

A weak pressure gradient prevails over much of the remaining
forecast region. Light to gentle winds with 3 to 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,
building seas 7 to 10 ft by early Thursday morning through the
end of the week. The pressure gradient across northwest Mexico
will increase Tuesday night with winds within 60 nm of the Pacific
coast of the peninsula increasing to moderate to fresh through the
end of the week.

Northwest flow in the far northern Gulf of California will
increase to fresh to strong Friday as the gradient also tightens
there.
  
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...

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

The tight pressure gradient responsible for the Gulf of Papagayo
gale force winds will support fresh to strong northeast winds
southwest of Nicaragua, including the Gulf of Fonseca, through
mid-week.

In the Gulf of Panama and near the Azuero Peninsula, northerly
winds have increased to 20 to 25 kt as strong winds have started
to funnel into the area from the southwest Caribbean. Winds are
expected to remain fresh to strong through mid-week before
diminishing. Seas will build to 8 to 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 120W by late Tuesday.

REMAINDER OF THE AREA...

A large occluded low pressure system north of the area extends a
cold front through 30N119W to 24N130W. Weak high pressure is
centered on either side of the cold front. The weak pressure
gradient over northern waters will allow winds to diminish
overnight. 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 over the northwest waters today.

The combination of swell generated from the Gulf of Papagayo and
Gulf of Tehuantepec gap wind events has generated an east to
northeasterly swell that is propagating from the area. This swell,
with seas greater than 8 ft, will move across the waters roughly
from 05N to 15N through the week. This swell will eventually
merge with fresh northeast-east tradewind swell across the west-
central waters by the end of the week.

$$
Mundell