000
AXPZ20 KNHC 201500
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1321 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 1200 UTC surface analysis and satellite imagery through
1500 UTC.

..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...         

The monsoon trough extends from 09N78W to 09N83W to 09N95W to
06N110W. The intertropical convergence zone axis extends from
06N110W to 04N117W. It continues from 10N125W to 07N140W.
Scattered moderate isolated strong convection is noted north of
03N and east of 84W. Scattered moderate convection was noted
within 120 nm of the monsoon trough between 94W and 110W.
Scattered moderate convection was noted within 120 nm of the ITCZ
between 110W and 117W. 

...DISCUSSION...   

North of 15N east of 120W:

A surface trough extends across the northern Gulf of California
toward Punta Eugenia on the Baja California peninsula. Gentle to
moderate northwesterly flow prevails west of the Baja California
peninsula, with seas to 7 ft off Baja California Norte extending
to 120W, and 4 to 6 feet elsewhere. Winds will continue to diminish
off Baja California Norte 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 within 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:

Gentle to 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. A new set of long period
southwesterly swell moving into the area will build wave heights
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.
Seas will finally start to subside 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.

$$
AL