000
AXPZ20 KNHC 200222
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0211 UTC Mon Jun 20 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
0200 UTC.

..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...         

The monsoon trough axis extends from low pressure near 09N74W to
09N94W to 08N100W to 13N114W. The intertropical convergence zone
axis extends from 13N114W to 09N130W to 08N140W. Scattered
moderate convection is within 240 nm to the south of the monsoon
trough and east of 94W. Similar convection is from 05N to 11N
between 111W and 116W.

...DISCUSSION...   

North of 15N east of 120W:

High pressure ridging prevails over the northern portion to the
west of the Baja California peninsula. A surface trough prevails
over the Baja California peninsula. The pressure gradient between
these two features has allowed for northerly winds to the north of
29N to increase to fresh to strong where seas are also up to 8
feet. These winds will diminish Monday as the trough shifts
westward off the coast of the Baja California peninsula. Otherwise,
mainly light to moderate northerly winds prevail outside of the
Gulf of California. Long period southwest swell will move to the
north of 15N through the early part of the week. The pressure
gradient between high pressure building over the Gulf of Mexico
and lower pressures with the monsoon trough over the eastern North
Pacific will help to support strong gap wind flow through the Gulf
of Tehuantepec, commencing Monday night. The mix of shorter period
wind waves from the gap winds with the longer period southwest
swell will result in areas of confused seas in and downstream of
the Gulf of Tehuantepec. In addition, the swell will bring the
potential for hazardous surf along exposed areas of the coast of
Mexico starting late Monday through the entire week.

South of 15N east of 120W:

Moderate monsoonal flow prevails to the south of the monsoon trough,
while gentle to moderate northeasterly trade winds prevail to the
north of the monsoon trough. Southwesterly swell in the 4 to 6 foot
range is within 250 nm offshore, and in the 6 to 9 foot range beyond
250 nm offshore as a new set of long period southwesterly swell
moves into the area. Wave heights will build to 6 to 9 feet across
the entire area Monday and Monday night, then to 7 to 10 feet Tuesday
and Tuesday night through the end of the week, finally starting to
decay Friday and Friday night. This swell will reach the coast of
Central America by mid week, creating the potential for hazardous
surf along exposed areas of the coast.

West of 120W:

The pressure gradient between high pressure anchored to the north
of the region, and low pressure within the monsoon trough and in
the vicinity of the ITCZ is supporting moderate to fresh winds,
with combined seas in the 4 to 7 foot range, except up to 8 feet
near the Equator. The ridge will prevail in the northern waters
during the next few days with these general conditions persisting.
A surge of northerly winds off the coast of Southern California
will push south of 32N by Monday, bringing fresh to strong winds
as far south as 27N between 120W and 128W, with seas of 7 to 9 feet
through the early part of the week. These conditions will shift
westward slightly Tuesday and Wednesday, persisting through the
end of the week.

$$
JLewitsky