000
AXPZ20 KNHC 281001
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Sun Apr 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 0600 UTC surface analysis and satellite imagery through
0945 UTC.

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

A trough extends from a 1010 mb low located over Colombia near 
07N74W. It extends to the coast at 07N78W, and continues to 
08N85W to 05N94W, where overnight scatterometer data indicates
that it transitions to the ITCZ and continues to 04N110W to 
04N120W to 04N130W and to beyond the discussion area at 05N140W.
Scattered moderate convection is seen within 180 nm north of 
the ITCZ between 94W and 99W, and also within 30 nm of the 
trough between 92W and 94W.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO... 

Relatively weak 1017 mb high pressure is centered to the west of
the offshore waters near 27N124W. The pressure gradient on the
eastern periphery of the high is maintaining gentle to moderate 
northwest to northwest to north winds over the forecast waters. 
Seas are in the 4 to 6 ft range. With the exception of winds 
briefly becoming fresh along and just offshore the central part 
of the Baja California Peninsula during the afternoons and at
night, expect near steady state conditions through Thu. A set of 
new north swell will propagate through 32N on Mon and affect the
offshore waters N of 27N through Tue night, causing seas there 
to build about a ft higher than the present peak of 6 ft. They
will subside back to the 4 to 6 foot range Thu.

Gulf of California: Fresh southwest winds over the northern Gulf
of California will become strong Mon night and Tue as a 
weakening trough approaches. Winds will then diminish to fresh 
around midday Tue then become generally light to gentle south to 
southwest winds Tue afternoon through Thu night. Seas over the 
northern part of the Gulf are presently 3 ft or less, but will
build to 5 to 7 ft on Mon, then subside to 2 to 4 ft on Tue as
winds diminish.

Gulf of Tehuantepec: Light and variable winds across the Gulf of 
Tehuantepec will become light to moderate onshore winds Mon 
through Thu night, with wave heights of 4 to 6 ft.

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

Gulf of Papagayo: Moderate to fresh northeast to east winds over
the Gulf of Papagayo region will increase to strong speeds late 
tonight, diminish to fresh winds Mon afternoon then pulse back to
strong winds at night from Mon through Thu.

Gulf of Panama: Moderate to fresh north winds will diminish to 
gentle speeds this afternoon, then increase to gentle to moderate 
speeds this afternoon and continue at those speeds through Mon
night before diminishing back to mainly gentle speeds on Tue and
changing little through Thu. Seas in this area will be maintained
in the 3 to 5 ft range as a result of the long-period south to 
southwest swell originating from the Southern Hemisphere.

Combined seas between Ecuador and the Galapagos Islands are in 
the 5 to 7 ft range in south to southwest swell based on the 
latest altimeter data in this region. The aforementioned
long-period south to southwest swell will keep wave heights 
in the range of 5 and 7 ft for the offshore waters west of 
Ecuador through Wed, subsiding slightly late Wed through 
Thu night.

Visible GOES-16 satellite images from Sat afternoon and early 
evening clearly depicted areas of smoke and haze, some in the 
dense category, along and adjacent to the coast of Central 
American as well as the coast of southeastern Mexico, including 
the Gulf of Tehuantepec region. The imagery revealed that the 
smoke and haze had spread out over a good portion of the Pacific 
offshore waters, including the Gulf of Tehuantepec to well 
offshore of the Gulf of Papagayo to 08N92W. This pretty much
falls in line with the smoke guidance issued by NOAA/NESDIS.
Ongoing agricultural burning, as normally carried during this 
time of year, from the past few days in southeastern Mexico and 
in Central America are primarily the source regions of the smoke 
and haze. Latest surface based observations highlight reduced 
visibility of 3-5 nm. This smoke may take several days to clear 
the region as the fires will continue and moderate northeast 
surface to low-level winds continue across these regions.

REMAINDER OF THE AREA...

Moderate northeast to east trades are over the waters from about 
06N to 17N and W of 110W along with wave heights in the range of
6 to 8 ft. Rather weak high pressure over the northern waters 
will maintain moderate trades across the trade wind belt through 
early next week, with little change in the wave heights.

A weakening 1016 mb surface low is analyzed near 30.5N129.5W, 
with a trough extending southwestward from the low to near
26N135W. The low is situated to the southwest of an upper-level
low near 32N128W, that has an east-northeastward motion. Scattered
showers and a few thunderstorms are noted within 180 nm in the 
SE quadrant of the upper-level low. The surface low is slowly 
moving in an eastward motion. It will continue eastward toward 
the northeast part of the area through late Mon while losing its 
identity. Model guidance suggests that it will most likely weaken
to a tough. Winds related to the low will remain less than 20 kt
with seas 6 to 7 ft across the far northwest part of the area. A
new batch of north swell will move south of 32N and between 124W
and 132W during Mon afternoon, and reach south to near 27N 
between 121W and 134W by late Mon night, with associated wave 
heights in the range of 7 to 9 ft.

Cross-equatorial southwest swell in the far southern waters will
propagate northward through much of the forecast area east of 
120W through Mon night and decay on Tue. Wave heights reaching to
8 ft will generally be confined to the waters south of the 01N 
and west of 95W. Wave model guidance is consistently indicating 
that a more extensive batch of Southern Hemisphere swell will 
propagate through the Equator by Thu night.

$$
Aguirre