000
AXPZ20 KNHC 261512
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1510 UTC Thu Sep 26 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 1200 UTC surface analysis and satellite imagery through
1500 UTC.

...SPECIAL FEATURES...

A broad area of low pressure located along the monsoon trough
near 16N113W continues to produce disorganized shower activity. 
Some development of this system is possible while it moves 
eastward and then southeastward during the next couple of days, 
and a tropical depression could still form before it becomes 
absorbed within a broad monsoon circulation near the coast of 
Mexico over the weekend. This system has a medium chance of 
tropical cyclone formation during the next 48 hours. Please see 
the latest Eastern North Pacific Tropical Weather Outlook for 
more information.

...TROPICAL WAVES...

A tropical wave axis is near 123W, moving west around 15 kt. No
significant convection is associated with this wave.

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

The monsoon trough extends from 07N77W to 1009 mb low pressure
near 16N100W to 1009 mb low pressure near 16N113W to 11N130W to
13N140W. Scattered moderate isolated strong convection is noted 
within 240 nm of the monsoon trough between 86W and 112W.
Scattered moderate convection is occurring from 02N to 06N east
of 80W, and within 120 nm of the monsoon trough west of 134W.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO... 

Overnight scatterometer data revealed light to gentle winds
across the Baja California offshore waters and the entrance to
the Gulf of California. Farther south, ship observations and
satellite derived wind data indicated fresh offshore winds south
of the monsoon trough, roughly between Acapulco and Puerto Angel.
Recent altimeter data showed 7-9 ft seas within this enhanced
monsoon flow near the far outer offshore waters.

The low pressure system described in the Special Features section
above will approach the waters south of the Revillagigedo Islands
today, then move east-southeastward Fri and Sat. This low will
likely become absorbed within a larger monsoon circulation that 
will strengthen off the southern coast of Mexico this weekend. 
Another low is expected to develop in this region along the 
monsoon trough during the next couple days, and it is likely to 
become a tropical depression over the weekend or early next week.
There is a high chance of tropical cyclone formation during the 
next five days. Regardless of development, heavy rainfall, with 
the possibility of flash flooding and mudslides, is likely along 
the Pacific coasts of Central America and southern and 
southwestern Mexico during the next several days. 

Elsewhere, a weakening cold front will drop southward into the 
northern waters this weekend, accompanied by increased NW swell. 

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

Fresh SW to W monsoon flow will persist off the coasts of 
Guatemala and El Salvador today through Sat, as an area of low
pressure is expected to develop off the southern coast of Mexico.
Offshore wave heights will build to 7-10 ft by Fri, with seas to 
8 ft spreading eastward towards Nicaragua and northern Costa 
Rica. Elsewhere, gentle to moderate winds will prevail for the
next several days with seas remaining less than 8 ft.

REMAINDER OF THE AREA...

Recent satellite derived wave heights indicate that 8 ft seas
that were occurring in the far western waters have now shifted
west of 140W. Light to moderate NE trade winds will persist north
of 17N and west of 130W for the next couple days.

Elsewhere, long period northerly swell is producing 7-9 ft seas
roughly north of 27N and west of 125W, based on recent altimeter
data. Wave heights will peak around 10 ft tonight and Fri. A cold
front will drop southward into the northern waters and weaken
this weekend. Expect moderate to fresh NE winds to develop north
of 26N and west of 125W on Sun following frontal passage.

$$
Reinhart