644 
AXPZ20 KNHC 241556
TWDEP 

Tropical Weather Discussion 
NWS National Hurricane Center Miami FL
1605 UTC Mon Sep 24 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 1200 UTC surface analysis and satellite imagery through 
1530 UTC.
    
...SPECIAL FEATURE... 

A broad area of low pressure is analyzed as 1009 mb surface low 
near 13N104W. Scattered moderate isolated strong convection is 
observed within 180 nm east semicircle of the low. Some 
tightening in the pressure gradient will increase the 
southwesterly monsoonal flow to a fresh to locally strong breeze 
well south of the low, across the tropical waters from 06N to 
12N between 107W and 116W over the next 24 hours. Environmental 
conditions are very favorable for tropical formation as this low 
tracks west-northwest over the next few days. Much uncertainty 
at this time, but for now expect fresh to strong winds, and 
building seas, to spread north across the offshore waters from 
16.5N to 23N on Wed through Sun, with southerly swell, in the 
form of 8 to 12 ft seas, to propagate north across the waters 
west of the Baja Peninsula during the upcoming weekend. Refer to 
the East pacific tropical Weather Outlook under WMO/AWIPS 
headers ABPZ20 KMIA/MIATWOEP for additional information.

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

The monsoon trough extends from 10N86W to 10N100W to a low 
pressure...possible tropical cyclone...near 13N104W to 10N107W 
to 11N125W to 10N136W. Scattered moderate isolated strong 
convection is in the Gulf of Panama and within 105 nm of Costa 
Rica. Scattered moderate convection is within 300 nm south of 
the monsoon trough between 110W and 124W, and from 06N to 16N 
west of 125W.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO... 

See the Special Features paragraph above. Surface ridging to the 
west will gradually retract away of the region during the middle 
of the week as a surface low, possibly a tropical cyclone, 
tracks west-northwest. Gentle northwest flow is forecast west of 
the Baja California through mid week, except becoming a moderate 
northwest breeze within 90 nm of the coast during the late 
afternoons and evenings.  

Gulf of California: Gentle to locally moderate variable winds 
forecast across the gulf waters north of 30N through this 
evening. Otherwise, light to gentle variable winds expected 
across the gulf waters through Friday.

Gulf of Tehuantepec: Strong northerly flow forecast through late 
this afternoon, then fresh to locally strong nocturnal drainage 
forecast to resume tonight with a strong event expected on 
Fri night.

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

Gulf of Papagayo: Moderate to locally fresh east nocturnal 
drainage flow expected through Thu night with seas building to 
8 ft. 
  
Light and variable winds are forecast elsewhere north of the 
monsoon trough which is meandering between 09N and 12N. Moderate 
southwest flow is forecast south of the monsoon trough.

REMAINDER OF THE AREA...   

See the Special Features paragraph above. A broad ridge 
continues across the subtropics accompanied by moderate to 
locally fresh anticyclonic flow south of 23N west of 120W.

$$
Ramos