000
AXPZ20 KNHC 122101
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2100 UTC Sun May 12 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 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 
The monsoon trough extends from northwest Colombia near 08N78W 
to 07N110W. The intertropical convergence zone reaches from 
07N110W to 06N125W to 08N140W. Scattered moderate convection is
observed from 04n to 09N between 85W and 89W. 

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO... 

A weak trough over Baja California Norte is all that remains from
a deep layer pressure area that moved across the northern Gulf of
California into the southwest United States earlier. The upper
low is still close enough to support a few showers and 
thunderstorms over the Sonoran Desert, and some of this activity 
may move offshore into the northern half of the Gulf of
California overnight. Ridging is building in the wake of the 
trough across the Pacific waters through the Revillagigedo 
Islands. An earlier scatterometer pass indicated a pulse of fresh
to strong NW winds to the southwest of Cabo San Lucas. These
winds are largely due to a tighter gradient between the ridge and
terrain onshore. 

Similarly, at least fresh NW winds will pulse off of Cabo 
Corrientes. A Cryosat altimeter pass from 16 UTC indicated seas 
to 8 ft just to the south of Cabo Corrientes. This was mainly due
to long period SW swell moving into the area, but also likely 
included a component of short period localized wind waves 
resulting from the fresh to occassionally strong NW winds off 
Cabo Corrientes. SW swell of 8 to 9 ft will persist from the 
Revillagigedo Islands through Cabo Corrientes and as far south as
off Acapulco through Tue before decaying below 8 ft.



Looking ahead, a weak frontal boundary may moving into the waters
off Baja California Norte Thu into Fri. The main impact for now 
appearing to be NW swell of 5 to 7 ft off Baja California Norte 
and fresh to strong gap winds into the northern portion of the
Gulf of California. 

Agricultural fires persist over of southern Mexico and the 
associated smoke is producing hazy conditions over the offshore 
waters along the coast of Mexico from the southeast part of the 
Gulf of Tehuantepec to near Manzanillo. The haze will most likely
remain through at least Mon night.

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

The main marine impact across the region continues to be long 
period southwest swell, which will support offshore wave heights
of 6 to 9 ft through mid week. High surf should be expected 
across the coasts of Central and South America and southeastern 
Mexico. Otherwise, the present synoptic pattern will allow light
to gentle breezes to persist. Occasional showers and 
thunderstorms will flare off the coast from western Panama to 
southern Nicaragua. 

Agricultural fires are occurring over northern Central America. 
However, the low-level southerly flow is generally keeping the 
associated smoke onshore and no substantial impact on visibility 
is occurring over the offshore waters at this time.

REMAINDER OF THE AREA...

A broad and weak ridge extends from a 1022 mb high pressure
system centered 33N140W southeastward to the Revillagigedo
Islands. This is producing a relatively weak pressure pattern, 
and only moderate northeast to east winds are occurring between 
the ITCZ and 15N and to the west of 110W. The high will shift 
slowly southeastward and weaken through Wed, ahead of a weak
front which will stall near 30N140W through Mon then dissipate.
The main impact will likely be W to NW swell of 5 to 7 ft north
of 25N and west of 130W through early next week. Looking ahead, a
weak trough may form along the ITCZ near 135W early in the week,
allowing moderate to fresh trades from 10N to 20N west of 130W
through mid week.

Waveheights are in the range of 8-10 ft to the S of 10N east of
135W are from a large set of southwest swell propagating through
this area. The swell will cover the the waters to south of 20N 
and east of 125W through early Tue before slowly decaying below 8
ft by Wed.

$$
Christensen