000
AXPZ20 KNHC 260228
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0228 UTC Wed Apr 26 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
0200 UTC.

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

A surface trough axis extends from 07N78W to 05N85W to 06N93W to
05N101W, where ASCAT winds indicate that the ITCZ forms and 
and continues west to 05N109W to 03N115W to beyond 05N124W. 
Scattered moderate isolated strong convection is within 60 nm 
south of the trough axis between 85W and 90W, and also between 
91W and 96W.

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

A tight pressure gradient over the northeast portion of the
area is producing strong northwest winds within 60 nm west of the 
Baja California Peninsula from 25N to 29N, and also north of 29N
east of 123W to the coast of the Baja California Peninsula. Seas
with these winds are in the 8 to 10 ft range, except for 10 to 11
ft seas north of 28N. Long period northwest swell elsewhere 
north of 21N between 111W and 124W is allowing for combined seas
of 8 to 10 ft within this area. The pressure gradient will relax
some  through Wednesday, then tighten again on Thursday. Expect 
strong NW winds to spread southward to along 28N and east of 125W
on Thursday with seas building to 10 to 13 ft by early Friday. 

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

A gentle onshore breeze is expected during the day, becoming 
offshore along the coast at night. Combined seas of 3 to 5 ft in
mixed SW and NW swell is forecast through Thursday.
 
REMAINDER OF THE AREA...
  
A 1027 mb high pressure center analyzed at 32N137W extends a 
ridge southeastward to near 21N115W. Associated high pressure 
covers the area north of 15N west of 115W. The pressure gradient 
between the ridge and lower pressure over Baja California with 
the typical thermal trough that develops is supporting strong 
northwest winds, with seas of 8 to 10 ft in the northeast part of
the area west of the offshore waters situated within 250 nm of 
the Mexican coast. These winds and seas will change little 
through Wednesday, then shift west-southwest Wednesday night 
through Thursday as the high pressure strengthens and the 
aforementioned ridging builds further to the east. Fresh 
northeast trades are present south of the ridge and north of the
ITCZ, with combined seas to 8 ft in mixed northeast and northwest
swell. This area of swell will gradually shift to the extreme
western portion of the area by Thursday night. Southern hemispheric
swell will approach the equator near the area between 105W and 
125W Thursday night, with resultant combined seas of 8 to 9 ft.

$$
Aguirre