000
AXPZ20 KNHC 291510
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1440 UTC Sat Dec 29 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 1200 UTC surface analysis and satellite imagery through
1500 UTC.

.INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 

A surface trough extends from Colombia near 05N77W to 03N82W to
04N86W to 04N95W. The ITCZ continues from 04N95W to 06N110W to 
04N123W to beyond 07N140W. Scattered moderate convection is 
noted within an area bounded by 07N131W to 18N111W to 13N106W to
06N116W to 05N131W to 07N131W.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO... 

Subsiding northerly swell is propagating across the offshore
waters of Baja California, with seas in the 7-9 ft range. Seas
will gradually subside below 8 ft by early next week. Another set
of northerly swell will propagate into the waters off Baja
California Norte building seas to near 10 ft Mon. This swell 
will subside through midweek. 

Gulf of California: High pressure over the Great Basin of United
States will support fresh to strong NW winds and building seas 
across the entire length of the Gulf by tonight. Strong NE gap 
winds are possible from La Paz on the Gulf side to Todos Santos 
and the Pacific side of the peninsula late today. Seas are 
forecast to be in the 6-8 ft range, with the highest seas north 
of 29N. The strong winds and associated seas will diminish Sun as
the high pressure weakens and shifts eastward. Looking ahead, 
this pattern will repeat early next week, with pulses of strong 
northerly winds returning to the northern Gulf of California late
Mon and Tue.

Gulf of Tehuantepec: Overnight drainage flow will bring a fresh 
to strong pulse of northerly gap winds into the Gulf of 
Tehuantepec tonight, followed by another fresh to strong pulse 
Sun night. Looking ahead, a strong gap wind event is expected 
late next week, possibly reaching strong gale force (40-45 kt) 
with building seas of 16-18 ft.

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

Fresh to strong NE to E winds are expected across the Gulf of 
Papagayo through mid week. The winds will peak during the 
overnight and early morning hours, and could reach near gale 
force with the assistance of the nocturnal drainage flow. 
Moderate to fresh N winds are expected across the Gulf of Panama 
through Wed. Elsewhere, gentle to moderate NE winds will prevail 
N of 08N, while gentle to moderate southerly winds are expected S
of 08N through Tue. 
  
REMAINDER OF THE AREA...  

High pressure of 1032 mb centered N of the area near 37N131W 
extends a ridge across the forecast waters to beyond the 
Revillagigedo Islands. The pressure gradient between this area of
high pressure and lower pressure in the vicinity of the ITCZ is
supporting fresh to strong tradewinds N of the ITCZ to near 20N
and W of 120W. The area of high pressure will remain in place N
of the area helping to maintain this area of fresh to strong
trades. Long period NW swell combined with tradewind swell is 
helping produce seas of 8 to 12 ft over much of the area north of
the ITCZ and west of 120W. 

Global models continue to indicate a cold-core upper disturbance
will dig into the base of a mid/upper level trough early next 
week, supporting the development of a sharp surface trough or 
even weak low pressure along the ITCZ near 120W by mid week. This
will likely enhance the trade winds north of the ITCZ and west 
of 120W, with near gale conditions possible on the northern end 
of the surface trough from 10N to 15N between 115W and 120W.

$$
AL