000
AXPZ20 KNHC 130940
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
940 UTC Thu Apr 13 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.

...SPECIAL FEATURES...

Gulf of Tehuantepec Gale Warning...The pressure gradient 
between the high pressure ridging surging down eastern Mexico and
lower pressures prevailing to the south of the Tehuantepec 
region continues to be tight enough to support minimal gale- 
force north to northeast winds in the Gulf of Tehuantepec. Seas
associated with these wind conditions are in the 8 to 12 ft 
range. Gale conditions will persist through the morning hours,
then will diminish to fresh to strong in the afternoon. Fresh to
strong northerly flow will then pulse, mainly at night with
nocturnal drainage flow, through the upcoming weekend, then will
be moderate early  next week.
 
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

The intertropical convergence zone axis extends from 02N96W to
03N120W to 03N140W. Scattered moderate and isolated strong
convection is north of the ITCZ within area bounded by 02N115W to
04N134W to 08N125W to 02N115W.

In addition, scattered moderate convection is from 03N to 04N
between 91W and 93W, and scattered moderate convection is from 
06N to 08N between 90W and 93W. This convection is associated 
with a weakening mid to upper level trough.

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

See the Special Features section for details on the Gulf of 
Tehuantepec Gale Warning.

A surface ridge extends from northwest to southeast across the 
offshore waters. Recent scatterometer data showed NW flow
increasing to fresh to strong offshore of Baja California Norte
where seas are up to 8 ft. Recent altimeter data showed fresh NW
swell across the offshore waters W of Baja California Sur. The
pressure gradient will remain tight enough to support these
conditions through Friday night, then will weaken thereafter.

In the Gulf of California, mainly light to gentle variable flow 
will prevail through the upcoming weekend into early next week, 
with seas mainly 2 ft or less, except 3 to 4 ft near the entrance
to the Gulf.

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 winds are expected to pulse through the upcoming 
weekend, then will be weaker early next week. Seas will build to
up to 8 ft by the early morning hours each day.

In the Gulf of Panama, moderate to fresh nocturnal northerly 
flow is expected during the overnight hours through the upcoming
weekend, then will be weaker early next week. Seas are expected 
to build to a range of 5 to 7 ft downstream of the gulf waters.
  
Elsewhere, light to gentle winds and combined seas of 3 to 6 ft 
will prevail during the next several days.

REMAINDER OF THE AREA...

A weakening cold front is analyzed over the N central waters from
30N124W to 26N133W with a reinforcing secondary front extending
from 30N129W to 29N132W to 27N140W. The boundaries will merge
during the next 24 hours, then will dissipate as they approach
the Baja California Peninsula Friday night. Associated winds with
both boundaries are 20 kt or less, however, NW swell up to 8 to
12 ft, highest along and N of 30N, will propagate across the
waters N of 20N into the early part of the weekend. The next cold
front will dip SE of 30N140W late Saturday with winds just ahead
of it nearing 20 to 25 kt near 30N. A new set of NW swell of 8 to
10 ft will arrive with the front but will quickly decay by the
end of the weekend into early next week.

Meanwhile, a ridge axis extends from 1021 mb high pressure near
27N125W to near 19N110W. Trades SW of the ridge and S of 20N area
fresh to locally strong with seas of 8 to 10 ft in fresh NE seas
and long period NW swell. The trades will weaken slightly 
through the end of the week, and the seas will very slowly decay 
to less than 8 ft by late Sunday into Monday.
  
$$
LEWITSKY