000
AXPZ20 KNHC 191504
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1250 UTC Sun Jun 19 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 08N78W to 09N88W to 07N102W to
10N111W. The ITCZ extends from 10N111W to beyond 09N140W.
Scattered moderate isolated strong convection is noted north of
02N and east of 84W. Scattered moderate convection is noted
within 120 nm south of the monsoon trough between 84W and 94W.
Scattered moderate convection was noted within 90 nm south and 120
nm north of the monsoon trough between 94W and 102W.

...DISCUSSION...   

North of 15N east of 120W:

High pressure ridge prevails over the northern waters west of
120W. A surface trough prevails over the Gulf of California. The
pressure gradient between these two features is supporting
moderate to fresh northwesterly winds over the waters west of Baja
California Norte out to 120W. Gentle to moderate winds prevail
elsewhere. Northwest winds will continue to increase off the
northern coast of Baja California Norte. These winds will
diminish Monday as the trough shifts westward off the coast of the
Baja California peninsula. Long period southwest swell will move
north of 15N early next week. The pressure gradient between high
pressure building over the Gulf of Mexico and the monsoon trough
over the eastern North Pacific will help for strong gap wind flow
into the Gulf of Tehuantepec. The mix of shorter period wind waves
from the gap winds and 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 mid 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. Subsiding southwesterly swell
continues to propagate across the area with seas in the 5 to 6
foot range beyond 250 nm offshore, and in the 3 to 5 foot range
within 250 nm offshore. A new set of long period southwesterly
swell will move into the area starting late today. Wave heights
will build to 6 to 9 ft on Monday and Tuesday, and then to 7 to 10
feet Wednesday and Thursday. 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 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 seas in the 4 to 7
foot range. 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 28N between 120W and 127W with seas to 8 ft by early
next week. These conditions will shift westward slightly Tuesday
and Wednesday, diminishing thereafter.

$$
AL