000
AXPZ20 KNHC 150948
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
658 UTC Sat Apr 15 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 0600 UTC surface analysis and satellite imagery through
0900 UTC.
 
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...  
The northern Intertropical Convergence Zone extends from 05N93W 
to 04N104W to 02N123W to 03N135W to 03N140W. Scattered moderate 
to isolated strong convection is noted within 90 nm either side 
of the ITCZ axis E of 107W. The southern Intertropical 
Convergence Zone extends from 03.4SN90W to 02S98W to 03S107W to 
beyond 03S120W. Scattered moderate to isolated strong convection 
is seen from 02S to 03.4S between 101W and 110W.

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

The pressure gradient between high pressure over eastern Mexico 
and lower pressures south of the Tehuantepec region will continue
to support fresh to strong northerly winds across the Gulf of 
Tehuantepec through early Sunday morning with the assistance of 
the nocturnal drainage flow. The high will shift east as low 
pressure develops over the Southern plains on Sunday, allowing 
the pressure gradient to decrease.

Low pressure approaching the west coast of the United States is 
weakening the high pressure ridge to the west of Baja. Winds and 
seas have begun to decrease accordingly. Moderate to fresh NW 
winds will become moderate and seas of 8 to 10 ft offshore of 
Baja California Norte will subside to less than 8 ft by Sunday. 
However, NW swell will continue to support seas up to 8 ft off 
the Baja California Norte through late Saturday. High pressure 
building in behind a cold front that will dissipate to the west 
of Baja will generate fresh to strong NW winds west along the 
length of the peninsula Tuesday through Friday. Seas will build 
to between 8 and 10 ft. This event should peak on Thursday.

Light and variable winds and seas generally below 2 ft will 
prevail across most of the Gulf of California during the upcoming
weekend as surface troughing over Baja reduces the local 
pressure gradient. Seas of 2-3 ft are expected near the entrance 
of the Gulf. Strengthening high pressure west of the peninsula 
will bring gentle to moderate NW winds to most of the Gulf by 
Wednesday evening.

OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND 
WITHIN 750 NM OF ECUADOR...

In the Gulf of Papagayo, fresh to locally strong nocturnal 
drainage flow is expected to occur early this morning and early 
on Sunday morning. Seas are expected to top out at 8 ft each 
morning.

In the Gulf of Panama, moderate to fresh northerly flow is 
expected during the overnight hours through tonight. Seas will 
be 5 to 6 ft downstream of the Gulf.
  
Elsewhere, light to gentle winds and combined seas of 3 to 6 ft 
will prevail through the weekend.

REMAINDER OF THE AREA...

A round of large period NW swell is affecting the offshore 
waters of Baja California. Seas in this area are running 8 to 10 
ft. This swell event has peaked and seas will subside to below 8 
ft Saturday night.

The next cold front is forecast to reach the northwest waters 
around noon on Saturday. However, fresh to strong S-SW winds in 
the 20-30 kt range have already entered the region ahead of the 
front. NW swell associated with this front will bring seas to 
between 9 and 11 ft in the far northwest portion of the 
discussion area today. Seas will subside Sunday morning as the 
swell energy decays. The front will reach a position from 30N136W
to 27N140W by this evening, and from 30N130W to 27N135W by 
Sunday evening as stalls and weakens. Moderate to fresh north 
winds will follow the front. 

A 1026 mb high pressure centered well north of area near 40N127W
ridges S to 29N127W, then SE to near the Revillagigedo Islands. 
The pressure gradient between the ridge and lower pressures in 
the vicinity of the ITCZ is generating moderate to fresh NE winds
roughly from 06N to 20N west of 115W. Associated seas are 
between 8 and 9 ft in mixed NW swell and NE wind waves. The high 
pressure will be displaced northward as it weakens due to the 
approaching cold front. As a result, the trades over the central 
and western portions of the forecast area will weaken. Then, 
marine model guidance suggests gentle to moderate trades over 
those sections of the forecast region. Seas within this area of 
trades will subside below 8 ft by Monday.
  
$$
cam