897 
AXPZ20 KNHC 121544
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Thu Jul 12 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 
1500 UTC. 

...TROPICAL WAVES...

A tropical wave is entering the eastern Pacific Ocean from 
Central America and is located near 86W N of 08N.  The wave is 
moving W at 10-15 kt.  It can be observed from the 700 mb 
rawindsonde winds from Panama, San Jose, San Andres, and Belize; 
Central American surface winds, as well as a maximum in total 
precipitable water.  Scattered moderate convection is occurring 
within 300 nm W of the axis over the eastern Pacific Ocean.

A tropical wave is from 08N to 18N along 108W, moving W at 15 
kt. This weak wave is only observable via 700 mb trough 
diagnostics. No significant deep convection is observed in 
association with this wave.  

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

The monsoon trough extends from a 1009 mb low over 
Colombia/Panama near 09N77W to 07N95W to a 1008 mb low at 
12N133W to 09N138W.  The ITCZ begins at that point and extends 
westward to beyond 09N140W.  Scattered moderate convection 
occurs within 180 nm S of the trough between 100W and 105W.   A 
large area of scattered moderate convection is from 10N to 14N 
between 118W and 137W.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Gulf of Tehuantepec: High pressure in the Gulf of Mexico and 
northerly winds east of a trough in the Bay of Campeche will 
enhance the nocturnal drainage flow in the Gulf of Tehuantepec. 
Peak winds may approach 30 kt each late night/early morning 
through Monday. 

A surface trough NW of Baja California is supporting a weak 
pressure pattern N of 15N W of 96W across the offshore waters, 
promoting mainly gentle winds. The trough will meander between 
115W and 120W during the next few days, which will help maintain 
weak flow across the region into the weekend.

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

Gulf of Papagayo: Strong nocturnal NE to E winds, with 8 to 10 
ft seas, are expected in the Gulf of Papagayo Friday night and 
Saturday.

Gentle to moderate easterly winds are expected elsewhere north 
of the monsoon trough, with gentle southerly winds forecast 
south of the trough axis.
  
REMAINDER OF THE AREA...

A 1008 mb low pressure center is analyzed near 12N133W. The low 
will move slowly NW during the next 24-48 hours. Fresh NE to E 
winds and 8 foot seas may develop within 90-210 nm north of the 
low center during the next 12-24 hours. Expect NE to E 20 to 25 
knot winds and sea heights reaching 8-9 feet within 200 nm to 
300 nm to the north of the low center during the next few days.

$$
Landsea/Mundell