000
AXPZ20 KNHC 200326
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Fri Jan 20 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 0000 UTC surface analysis and satellite imagery through 
0300 UTC.

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

The intertropical convergences zone extends from 06N88W to 
04N109W to 05N140W. No significant convection.

...DISCUSSION...   

...A series of strong cold fronts and a prolonged period of 
unusually large swell will affect much of the area...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

A cold front moving into Baja California Norte extends from 
30N117W to 26N128W, then diffuse stationary to 25N137W. The 
front will sweep across the northern Gulf of California and 
weaken overnight. Large northwest swell associated with the 
front will push southeastward, and affect the west coast of Baja 
California tonight and Friday. Strong southwest winds ahead of 
the front north of 29N in the Gulf of California will diminish 
slightly Friday. Then, a stronger cold front will sweep eastward 
into Baja California Norte Friday night, with even stronger 
winds and higher seas. Large northwest swell will build max seas 
to 16-20 ft in Pacific waters north of 25N through Saturday 
night. Mariners can expect hazardous marine conditions near 
shore and coastal waters, with very dangerous surf conditions 
along the coast.

High pressure building behind the front will support strong 
northerly flow off the southern Gulf of California and off Cabo 
Corrientes by late Sunday as the leading edge of the large NW 
swell event reaches the coast near Manzanillo. Another front 
will push into to the waters off Baja California Norte by late 
Sunday with another round of strong northwest winds and 12 to 15 
ft northwest swell.

Farther south, a cold front moving through the western Gulf of 
Mexico will prompt strong gap winds in the Gulf of Tehuantepec 
Sunday night and Monday morning.
  
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...

Light to gentle easterly winds will prevail across the region, 
except for periods of moderate gap winds through the Gulf of 
Papagayo, into Saturday. Seas will be generally 3-5 ft in the 
forecast waters.

REMAINDER OF THE AREA...

A ridge extends eastward along 25N to the Baja peninsula. The 
gradient between the ridge and low pressure associated with the 
ITCZ is supporting a decreasing area of fresh northeast trade 
winds west of 130W, with 8-9 ft seas. Moderate to fresh trades 
are elsewhere from 07N to 20N west of 122W. Seas within areas of 
fresh trades are 7-8 ft in mixed NE and NW swell. Expect the 
trades to decrease in areal coverage and shift westward through 
Saturday.

A second cold front is expected to sweep southeastward across 
the northern waters tonight through Friday night. Wave model 
guidance shows unusually large northwest swell will propagate 
southeastward into the waters north of 20N behind the second 
front, with seas building to 16-22 ft north of 25N and east of 
130W Saturday. Yet another cold front will move into the far 
northwest waters on Saturday, preceded and followed by strong 
winds. This front will generate another set of large northwest 
swell through the northwest waters, with wave model guidance 
indicating seas in the 14-21 ft range.

$$
Mundell