000
AXPZ20 KNHC 080308
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
056 UTC Sat Dec 8 2018

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 0000 UTC surface analysis and satellite imagery through
0245 UTC.

...SPECIAL FEATURE...

Gulf of Tehuantepec: Winds and seas have diminished as weak high
pressure shifts NE away from the western Gulf of Mexico. The 
next gap wind event will have an abrupt beginning Sun afternoon 
as strong high pres builds southward behind a cold front blasting
S along the Sierra Madre Oriental mountains of Mexico. Gale to 
strong gale conditions are expected Sun evening through Wed, then
winds will abruptly decrease as well. The area of high seas 
generated by this event will spread WSW nearly a thousand miles 
from its source region by Tue night.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 

The monsoon trough axis extends from 08N75W to 09N87W to 07N94W
to 06N100W. The ITCZ continues from 06N100W to 06N107W to 
08N124W, then resumes from 08N127W to 08N133W to beyond 07N140W.
Numerous moderate and scattered strong convection is seen from 
08N to 10N W of 135W. Scattered moderate convection is present 
from 06N to 09N between 95W and 98W.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO... 

A 1024 mb high centered near 32N128W will maintain moderate to 
fresh NW to N winds over the offshore waters W of Baja tonight, 
then light to moderate N to NE winds over the same waters Sat 
through Sun night. Long period 7 to 10 ft NW swell will sweep SE 
to near 110W by Sat, then gradually subside through Sun night.
Strong high pressure building over the Great Basin will generate
strong winds over the Gulf of California within 60 nm of the E
coast of Baja California Sur on Sun.

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

Gulf of Papagayo...Nocturnal fresh to locally strong NE winds, 
and 6 to 8 ft seas, will linger tonight, then subside Sat. Fresh
to strong winds will resume pulsing over the Gulf of Papagayo 
Sun night through Wed night.

Elsewhere, the monsoon trough will meander between 08N and 10N
through Wed night. Light to gentle winds will generally prevail 
on either side of the trough along with 3 to 6 ft seas. 
  
REMAINDER OF THE AREA...  

A cold front will weaken and stall near 30N140W tonight. A 
reinforcing cold front will reach 30N140W Sat evening, 
accompanied by fresh winds and additional large long period NW 
swell to 16 ft. This cold front will weaken as it moves eastward 
toward Baja California Norte through early next week. Winds on 
the lee side of these fronts will continue to generate long 
period NW swell which will maintain seas 8 ft or above for most 
of the forecast waters W of 100W though Wed night.

The long period NW swell will continue propagating SE to 
encompass almost all of the forecast waters W of 100W by Sat 
evening. This area of swell will decay by Mon. Combined waves 
from trade winds and swell will support a large area of 8 to 10 
ft seas south of 17N and west of 105W by Sun night. This area 
will retreat to the W of 120W by Tue afternoon, but an area of 
strong trade winds will develop between 10N and 25N by Tue night 
in response to building high pres N of the forecast area.

$$
CAM