000
AXPZ20 KNHC 220903
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
903 UTC Thu Jun 22 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 0600 UTC surface analysis and satellite imagery through
0830 UTC.

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

The monsoon trough axis extends from 09N79W to low pressure near
12N94W to 11N110W to 08N130W. The intertropical convergence 
zone axis extends from 08N130W to 09N140W. Scattered moderate and
isolated strong convection is from 04N to 11N between 83W and
93W, from 05N to 09N between 99W and 105W, from 08N to 11N
between 109W and 113W, and from 08N to 10N between 118W and 124W. 

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Gentle to moderate northerly flow is noted off Baja California 
Norte between troughing over the the peninsula and ridging well 
to the NW. This is supporting moderate to fresh SE winds over 
the Gulf of California as well. Northerly swell of 7 to 9 ft is 
propagating into the waters off Baja California Norte N of 24N. 
Elsewhere, the weak troughing across the Gulf of California and 
into the adjacent Pacific waters off Baja California are 
maintaining generally light to gentle breezes across the region. 
The troughing over the Baja California will move W through 
today, enhancing southerly flow near Los Cabos and across much of
the Gulf of California into Saturday when the gradient relaxes.

Farther S, a weak area of low pressure is located S of the Gulf 
of Tehuantepec near 12N94W. Scattered showers and isolated 
thunderstorms are within 180 nm in the N semicircle of the low. 
This will support moderate to fresh E to SE winds off the coasts 
of Chiapas and Oaxaca through Saturday as the broad weak low 
shifts W. 

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

Gentle to moderate SW to W winds are expected across most of the
forecast area during the forecast period, with the exception of 
mainly S winds between Ecuador and the Galapagos Islands, as the
pressure gradient remains weak. Long period SW swell of 5 to 7 
ft will gradually decay through the upcoming weekend.

Scattered showers and thunderstorms are active off the Pacific 
coast from 01N to 06N and E of 82W offshore of Pacific coast of 
Colombia, related to an upper low pressure area over the SW 
Caribbean Sea between Nicaragua and Jamaica. 

REMAINDER OF THE AREA...
 
A ridge dominates most of the waters N of the convergence zone. 
Scatterometer and altimeter passes continue to indicate an area 
of moderate to fresh winds and seas of 8 to 10 ft roughly N of 
20N and W of 120W. The ridge will shift W as a weak low near 
18N118W with an attendant trough drift W. The low and troughing 
will continue to drift SW to W through the end of the week before
dissipating early this weekend.

Northerly swell will continue to propagate across the waters
N of 20N, building to 10 to 12 ft N of 28N through Friday, as 
fresh swell moves in around a low pressure system N of the area.
Seas will decay through the upcoming weekend as the low moves NW
while weakening.

$$
Lewitsky