532 
AXPZ20 KNHC 220934
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
934 UTC Wed Aug 22 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. 

...TROPICAL WAVES...

A tropical wave along 92W is moving W around 10 kt. Scattered
moderate convection is noted well west of the tropical wave axis,
and north of the monsoon trough, from 10N to 13N between 94W and
101W. 

A tropical wave from 05N to 18N along 108W is moving W around 15
kt. No significant convection is evident.

A tropical wave from 06N to 1011 mb low pressure near 10N123W, to
15N, moving W around 10-15 kt. Scattered moderate to isolated
strong convection is from 11N to 15N between 120W and 125W.

A tropical wave along 138W is moving W around 10-15 kt. No
significant convection is evident.
   
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 

The monsoon trough extends from 10N75W to 07N105W to 12N118W to
10N135W. Scattered moderate to isolated strong convection is
evident north of 05N east of 85W, and from 11N to 15N between
120W and 125W.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO... 

In the Gulf of Tehuantepec, a scatterometer pass from 04 UTC
indicated fresh to strong gap winds reaching approximately 100 nm
SSW of the Gulf of Tehuantepec. This strong pulse is due to a
tight pressure gradient between high pressure north of the area 
and lowering pressure farther south in the tropics. This pattern
is supporting development of strong mainly overnight and early 
morning pulses through the Gulf of Tehuantepec this morning and 
reoccurring Wed night and Thu night, with minor pulses possible 
thereafter. Seas may build briefly to 9 ft during these pulses.

Elsewhere, ridging across the waters north of 20N will support
moderate to occasionally fresh winds funneling along the coast 
of Baja California through the next several days, with 3 to 5 ft 
seas, with highest seas off Baja California Norte. Gentle to 
moderate southerly flow will persist over the Gulf of California.

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

The monsoon trough will linger between 08N to 12N during the 
next few days. Winds on both sides of the trough axis will 
generally be light to moderate. The main exception to this will 
be over the Gulf of Papagayo, where moderate to fresh offshore 
winds will pulse to locally strong each night. Seas are expected 
to remain 6-7 ft downstream of Papagayo during this time.

REMAINDER OF THE AREA...   

Elsewhere, the pressure gradient between ridging across the 
northern waters and the ITCZ will support gentle to moderate 
trades and 4-7 ft seas in mixed swell north of the ITCZ and west
of 120W through the weekend.

Sea heights will be relatively low for most of the forecast area 
this week. Robust long period swell could arrive from the 
Southern Hemisphere toward the end of this week and cause seas 
near the Equator to begin building over the weekend.
  
$$
Christensen