367 
AXPZ20 KNHC 170930
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Mon Sep 17 2018

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. 

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

The monsoon trough axis extends from northern Colombia near 
09N74W to 10N93W to 17N110W to low pressure 1007 mb centered 
near 17N119W to beyond 10N140W. Scattered moderate isolated 
strong convection is within 120 nm of the coast from Guatemala 
to northern Panama. Scattered moderate convection is from 10N to 
20N between 100W and 122W, and from 06N to 13N west of 130W.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO... 

A surface trough over the Baja Peninsula will generally maintain 
light to moderate winds over the Gulf of California through Tue 
morning. Afterwards, the winds are forecast to increase to 
moderate to fresh speeds in response to a high pressure ridge 
building to the NW. Winds over the gulf N of 29N are forecast to 
become strong and from the SE early on Wed continuing through 
Thu morning. Fresh to strong winds are then expected to develop 
across the central Gulf of California through Thu night. The 
same high pressure will generate fresh winds W of Baja 
California Norte Mon night through Wed morning with seas to 8 
ft. Pulses of long period SW swell will continue to impact the 
entrance of the Gulf of California, and the waters W of Baja 
California through Tue night.

Moderate to fresh monsoonal flow along with a 1007 mb low 
centered SW of the Revillagigedo Islands near 17N119W are 
supporting seas to 9 ft in the offshore waters between Jalisco 
and the Revillagigedo Islands south of 21N. This low is forecast 
to continue a southwest track the next three days, thus allowing 
for a decrease in the winds and seas in the offshores of Baja 
California Sur today. A new center of low pres is forecast to 
develop just west of the Revillagigedo Islands tonight. The low 
is expected to stay nearly stationary through Tue evening, then 
it will start tracking NNE and reach central Baja early on Thu. 
There is still a high chance of this system on becoming a 
tropical cyclone within the next 5 days.

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

The monsoon trough is expected to remain in the vicinity of 07N 
to 12N during the next several days. Winds will be light to 
gentle N of the trough and gentle to moderate S of the trough, 
except today when moderate winds will funnel through the Gulf of 
Papagayo extending to the Nicaragua, El Salvador and Guatemala 
offshore waters.

Cross-equatorial SW swell will continue to impact the coast of 
Central America through Tue night followed by a pulse of long 
period swell of 20 seconds reaching the coastal waters on Wed 
morning. Seas are expected to be in the 5 to 7 ft range.

REMAINDER OF THE AREA...   

The surface trough, remnant of Paul, has moved west of the area. 
However, a tighten pressure gradient between this elongated area 
of low pressure and a 1021 mb high just north of the area 
support fresh to locally strong east winds from 18N to 24N west 
of 133W. Latest altimeter data show seas to 8 ft in this region. 
Enhanced winds and seas in this region of the basin is forecast 
to continue through Thu.

Otherwise, the low currently southwest of the Revillagigedo 
Islands near 17N119W will continue to track west-southwest the 
next few days. The area of winds and seas associated with this 
low will gradually expand and combine with the area of winds and 
seas mentioned in the previous paragraph by late Tue night.

$$
Ramos