000
AXPZ20 KNHC 170855
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
855 UTC Wed Jun 17 2020

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
0900 UTC.

...TROPICAL WAVES...

A tropical wave is along 90W-91W, moving west at 10 kt. 
Scattered moderate to isolated strong convection is noted from 
10N to 12N within 90 nm of the wave axis along the monsoon 
trough. Strong convection is also noted within 60 nm of the coast
of Guatemala ahead of the wave axis.

A tropical wave is along 103W, moving west 5-10 kt. Scattered 
moderate to isolated strong convection is ongoing from 09N to 
12N within 120 nm east of the wave axis.

A tropical wave is analyzed along 121W, moving west around 10 to
15 kt. This wave well represented in low level satellite derived
wind fields and lower level precipitable water fields also. The 
wave shows up well because it is interacting with an upper low 
situated to its northwest. Scattered moderate convection is 
active within 90 nm of the wave axis from 10N to 12N. 

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 
The monsoon trough extends from 09N85W to 012N120W to 11N118W to
10N135W. The ITCZ continues from 10N135W to beyond 09N140W. 
Scattered moderate to isolated strong convection is noted from 
07N to 11N between 88W and 95W, and from 09N to 12N between 100W 
and 102W. Scattered moderate convection is noted from 07N to 10N 
west of 130W.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Fresh to strong northerly gap winds may again be pushing into 
the Gulf of Tehuantepec this morning, squeezed between lower 
pressure over the southwest Gulf of Mexico and the higher terrain
over southern Mexico. The lower pressure has been enhanced over 
the past couple of days by a mid to upper level trough extending 
across the region from the northeast Gulf of Mexico. This mid to 
upper trough is dampening out, so the pattern will change through
tomorrow and the gap winds will taper off. Seas may reach 7 ft 
downstream of the Gulf of Tehuantepec, mixing with longer period 
southerly swell. Looking ahead, gentle to moderate breezes will 
persist in Tehuantepec through most of the remainder of the week.
Brief pulses of fresh gap winds may return by late Sat. 

Farther north, a deep layer ridge west of the area is building 
eastward following a sharp trough now extending from the southern
Rockies through the central part of the Baja California 
peninsula into the open Pacific to 22N130W. This is tightening 
the gradient enough at the surface to support brief pulses of 
fresh to strong gap winds into the northern Gulf of California 
currently. A brief repeat of the fresh to strong winds is
possible tonight as well. The gradient will relax through late 
in the week as the ridge continues to build eastward. Meanwhile 
NW swell producing seas of 7 to 8 ft in the outer offshore waters
of Baja California Norte will subside tonight, before another 
pulse of NW swell to 8 ft will enter the waters northwest of 
Guadalupe Island by through late Wed. Looking ahead, moderate to 
fresh NW winds are possible off Baja California Sur by late week 
as a ridge builds into the area.

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

Gentle to moderate SW monsoon flow prevails south of the monsoon
trough, with gentle to moderate winds to the north of the 
monsoon trough. Seas are in the 5-7 ft range, mainly south of
Panama. This will subside through mid week, but another round of
SW swell is expected later in the week.

REMAINDER OF THE AREA...

A ridge extends from 1033 mb high pressure centered near 38N138W
E-SE to the Revillagigedo Islands. The pressure gradient between
this area of high pressure and lower pressure in the vicinity of
the ITCZ is supporting fresh trade winds from 10N to 25N west of
125W. Seas are in the 7 to 9 ft range over this area in a mix of
swell. Moderate to fresh winds, and seas of 5 to 7 ft, prevail 
elsewhere north of the monsoon trough/ITCZ. 
 
Moderate southerly flow prevails south of the monsoon 
trough/ITCZ. Long-period southerly swell still dominates the 
waters south of 10N and east of 110W, with 6 to 8 ft seas
prevailing. Another round of southerly swell will enter the area
late in the week.

$$
Christensen