099 
AXPZ20 KNHC 152205
TWDEP 

Tropical Weather Discussion 
NWS National Hurricane Center Miami FL
2205 UTC Sun Jul 15 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 1800 UTC surface analysis and satellite imagery through 
2100 UTC.  

...SPECIAL FEATURE...

A broad 1008 mb surface low is centered near 13N136W, embedded 
on a NNE-SW oriented trough. The ASCAT scatterometer passes 
around 18 UTC did not go through the center, though they did 
report peak winds of 40 kt with the system.  However, these are 
rain inflated and not reliable.  Peak sustained winds are likely 
25-30 kt at this time.  Additionally, a TOPEX altimeter pass 
around 15 UTC showed max seas of 8-10 ft.  Scattered moderate 
and isolated strong convection is occurring within 180 nm of the 
system's center. The system's center should reach our western 
border at 140W by Mon morning and associated strong winds out of 
our area by late Mon. This system does have a moderate - 60 
percent - chance of becoming a tropical cyclone within the next 
48 hours. Refer to the EPAC Tropical Weather Outlook under 
AWIPS/WMO headers MIATWOEP/ABPZ20 KNHC for additional 
information. 

...TROPICAL WAVES...

A tropical wave extends from the eastern Pacific near 05N84W 
northward to over Central America to near 18N85W. The wave is 
moving W at 15-20 kt. The wave is identifiable from the Caymen 
Islands rawindsonde, the 700 mb trough diagnostics, and the 
total precipitable water imagery. Scattered moderate convection 
is occurring over Nicaragua and Honduras.

A tropical wave is analyzed from 05N to 14N near 98W and is 
estimated to be moving W at 15 kt.  The wave is only 
recognizable via the 700 mb trough diagnostics.  No significant 
deep convection is associated with the system at this time.

A tropical wave is analyzed from 05N to 15N near 107W and is 
estimated to be moving W at 15-20 kt.  A 1011 mb low pressure 
center is analyzed to be along the wave's axis near 11N111W. 
This wave can be identified by a maximum in the total 
precipitable water imagery as well as the 700 mb trough 
diagnostics. Scattered moderate and isolated strong convection 
is occuring wihtin 180 nm of the low's center.

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

The monsoon trough axis extends W from a 1009 mb low near 10N75W 
over the coast of Colombia, across Panama, and to a 1011 mb low 
at 11N111W.  The ITCZ axis extends from 11N111W to 09N128W. 
Isolated moderate convection is occurring within 180 nm S of the 
trough E of 95W.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Gulf of Tehuantepec:  Strong pulses of northerly gap wind flow 
is expected during late night and morning hours through Wed. 
Seas will peak at 8 to 9 ft.  Conditions will subside on Thu and 
Fri. 

A surface ridge will meander across the area from 23N116W to 
15N100W this week. Quiescent winds and seas prevail outside of 
the Gulf of Tehuantepec.   

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

Gulf of Papagayo: Moderate to strong late night/morning NE to E 
winds will occur across and within 180 nm SW of the Gulf of 
Papagayo through at least Thu night. 

Elsewhere winds and seas are quiet.

The extended outlook is for long period southerly swell of 7 to 
9 ft arriving along 03.4S E of 93W Wed and reach along 10N this 
coming weekend.  

REMAINDER OF THE AREA...

Refer to Special Features section above for information on a 
weak surface low near 13N136W.  

A surface ridge will meander across the discussion area from 
32N140W to 23N116W this week, with winds and seas remaining 
quiet over the remainder of the area.

$$
Landsea