000
AXPZ20 KNHC 282118
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1943 UTC Tue May 28 2019

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 1800 UTC surface analysis and satellite imagery through
2100.

...SPECIAL FEATURES...

...Heavy Rainfall Potential Over Central America...

A large low level cyclonic circulation that is typical for this 
time of the year, called a Central American Gyre, is forecast to 
persist across the far eastern tropical Pacific and Central 
America for the next several days. Abundant moisture and 
increasing instability are expected through Wed, which could 
lead to a very significant rainfall event over portions of 
Central America. Life-threatening flash flooding and mudslides 
will be possible in areas of mountainous terrain. Please refer to
your local meteorological service for more details. 

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

The monsoon trough extends across northern Costa Rica to 1008 mb
low pressure near 10.5N88.5W to 12N100W to 08N115W to 10N127W. 
The ITCZ continues from 10N127W to beyond 07N140W. Scattered 
moderate to isolated strong convection is observed from 07N to 
13N between 81W and 102W. 

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO... 

A ridge extends across the northern forecast waters reaching 
the Baja California peninsula. Recent scatterometer data provided
observations of fresh to strong NW over the waters N of 22N E of
117W to the coast of Baja California. Mainly moderate NW winds 
dominates the remainder of the offshore waters. Seas are in the 6
to 8 ft seas in this region. Light to gentle winds, with seas 
in the 4-6 ft range prevail elsewhere over the open waters off 
Mexico. Light winds and seas 2 ft or less are noted over the 
Gulf of California.

High pressure will weaken slightly by Wed. This will diminish
winds to 20 kt or less west of the Baja California peninsula,
with seas subsiding below 8 ft. SW winds will strengthen south of
the Gulf of Tehunatepec by midweek.

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

Please see the Special Features section for more information 
about the Central American Gyre, which will continue to bring 
locally heavy rains to parts of Central America and the adjacent
offshore waters through at least mid week.

Latest surface observations indicate moderate to fresh S to SW 
winds S of the monsoon trough, with seas in the 6-8 ft range. 
Moderate to locally fresh winds, and seas of 5-6 ft prevail N of 
the monsoon trough. Low pressure of 1008 mb embedded within the 
broad gyre is centered offshore the coast of Nicaragua. The 
monsoon trough will lift northward by midweek, with the low 
pressure likely moving inland over Central America by midweek. 
The southerly monsoon flow is forecast to strengthen to 20-25 kt 
by Wed. Seas will also build to 8-12 ft by mid week as locally 
generated wind waves in the enhanced monsoon flow combines with 
cross equatorial SW swell.

REMAINDER OF THE AREA... 

A ridge extends from 1029 mb high pressure centered near 33N137W
southeastward through the Revillagigedo Islands. The pressure 
gradient between the ridge and lower pressure in the vicinity of 
the ITCZ is supporting moderate to fresh NE winds across much of 
the area north of the ITCZ and west of 120W. Moderate to fresh 
winds will continue to prevail over this area the next several 
days.

Long period cross equatorial SW swell will continue to dominate
much of the forecast waters. Seas 8 ft or greater cover the 
waters south of 11N between 85W and 115W. Seas will slowly 
subside the next couple of days, with areal coverage of seas 8 ft
or greater gradually decreasing. 

$$
GR