000
AXPZ20 KNHC 200902
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
439 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 0600 UTC surface analysis and satellite imagery through
0900 UTC.

..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...         

The monsoon trough axis extends from 11N86W to 08N107W to
08N117W. The intertropical convergence zone axis extends from
11N125W to 08N135W to 07N140W. Scattered moderate convection is
within 150 nm to the south of the monsoon trough between 92W and
97W. Scattered moderate convection is also noted north of 03N and
east of 80W toward the coast of Colombia.

...DISCUSSION...   

North of 15N east of 120W:

The latest surface analysis shows a 1004 mb low pressure area
centered over the lower Colorado River valley, with a surface
trough reaching across the northern Gulf of California toward
Punta Eugenia on the Baja California peninsula. Fresh
northwesterly flow is pushing south of 32N, between the lower
pressure to the east and high pressure centered west of the area,
with seas to 7 ft. Winds will diminish off Baja California Norte
later today as the trough shifts west into the Baja Coastal
waters. 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 tonight.
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 today 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 through tonight, then to 7 to 10 feet Tuesday and
Tuesday night through the end of the week, finally starting to
decay Friday and Friday night from south to north. 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:

A surge of northerly winds off the coast of Southern California
is pushing south of 32N, and will bring 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.Elsewhere 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.

$$
CHRISTENSEN