000
AXPZ20 KNHC 121520
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1520 UTC Fri May 12 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 1200 UTC surface analysis and satellite imagery through
1400 UTC.

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

The monsoon trough extends from 10N85W to 1009 mb low pressure 
near 13N96W to 05N112W. The ITCZ extends from 05N112W to 04N125W 
to beyond 04N140W. Scattered moderate to strong convection are 
from 04N to 14N between 82W and 90W. Scattered moderate with 
isolated strong convection are from 02N to 16N between 90W and 
100W, and within 240 nm of the ITCZ axis W of 130W. Scattered 
moderate convection is from 04N to 14N between 100W and 106W. 

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Scatterometer data from earlier this morning confirmed moderate
to fresh northwest winds west of Baja California. Surface
observations indicate light winds over northern Gulf of
California and moderate northwest winds over southern Gulf of
California. Gentle to moderate winds are elsewhere over the
Mexico offshore waters with seas of 4 to 6 ft covering all
Mexico offshore waters this morning, except Gulf of California
where seas are 1 to 3 ft. 

Later today and into tonight, the pressure gradient will tighten
offshore Baja California between high pressure northwest of the 
region, and developing low pressure inland over the SW United 
States. This will result in fresh to strong northwest winds and 
seas building to 8 to 12 ft west of northern Baja California 
through Saturday night. Swell greater than 8 ft generated by 
these winds will propagate west of southern Baja California 
through Sunday and will linger west of northern Baja California 
through Monday. Latest GFS guidance also indicates strong SW 
winds will develop over the northern Gulf of California Saturday 
night as the low deepens over the western Untied States.


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

Gentle to moderate winds will prevail over the forecast waters 
the next several days. Seas are in the 4-6 ft range and will 
remain that way through Tuesday. Seas will subside to the 3-5 ft
range by early next week. By mid week, Long period SW swell to 7
ft may reach the Colombia and Ecuador offshore waters north of 
the Equator.

REMAINDER OF THE AREA...

A dissipating cold front extends across the northern portion of 
the discussion area from 30N124W to 27N140W. The front will 
dissipate through today. High pressure will build in the wake of
the front, supporting fresh winds north of 22N and west of 126W
tonight through Saturday night with seas of 8 to 9 ft. North of
26N and east of 126W, north to northwest winds will increase to
20 to 25 kt by tonight and persist through Saturday night with
seas building to 8 to 12 ft. The seas above 8 ft will gradually 
subside through early next week. Moderate to fresh winds will 
prevail elsewhere north of the ITCZ.

$$
LATTO