000
AXPZ20 KNHC 051536
TWDEP 

Tropical Weather Discussion 
NWS National Hurricane Center Miami FL
1605 UTC Wed Jul 5 2017

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.

...SPECIAL FEATURE...

A surface low is analyzed near 18N117W, moving in tandem with a 
tropical wave along 117W that extends from 11N to 21N. Satellite 
imagery shows a well defined exposed low level center on the 
northern edge of the convection associated with the wave. ASCAT 
data shows fresh to strong SW monsoonal flow south of the low. 
Scattered moderate to strong convection is within 120 nm either 
side of the wave axis south of 17N. Short term environmental 
conditions are marginally favorable for further development, and 
the disturbance may become a tropical cyclone in the next 48 
hours before it reaches colder waters. Please refer to the NHC 
Tropical Weather Outlook at hurricanes.gov for more information.

...TROPICAL WAVES...

In addition to the wave mentioned above along 117W, a tropical 
wave is analyzed from 06N104W to 15N107W. Scattered moderate 
convection is noted within 150 nm either side of the wave axis. 
Model guidance suggests that a surface low may develop along 
this wave near 10N in a day or so, and long term environmental 
conditions appear to be favorable for further strengthening of 
this low. Please refer to the NHC Tropical Weather Outlook at 
hurricanes.gov for more information.

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

The monsoon trough extends across Panama and Costa Rica from a 
low near 09N76W into the east Pacific near 09N106W to 11N110W, 
then resumes from a low near 18N117W to 11N126W to 10N140W. 
Scattered moderate isolated strong convection is evident from 
05N to 07N east of 91W, and from 07N to 14N between 91W and 
107W. Scattered moderate isolated strong convection is also 
found within 90 nm either side of a line from 15N116W to 09N125W 
to 08N138W.

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

A ridge of high pressure extends across the waters west of Baja 
California. Light to moderate anticyclonic flow prevails west of 
the Baja California peninsula, moderate to fresh N winds in the 
Gulf of Tehuantepec, and light to gentle winds over the Gulf of 
California. Seas are 4-6 ft in the open waters west of Mexico, 
with 1-2 ft seas in the Gulf of California. Nocturnal winds will 
pulse to near 25 kt each night in the Gulf of Tehuantepec, and 
diminish during the day. Little change is expected elsewhere.
    
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND 
WITHIN 750 NM OF ECUADOR... 

Moderate to locally fresh nocturnal winds are expected in the 
Gulf of Papagayo this week. Gentle to moderate southerly winds 
are expected south of the monsoon trough this week. Long period 
cross-equatorial S to SW swell will build seas west of Colombia 
and Ecuador Wednesday night and Thursday, then subside Friday.

REMAINDER OF THE AREA...
  
See special feature section for more information on the low 
centered near 18N117W. Outside the monsoonal influence of this 
area, gentle to moderate trade winds will prevail north of the 
monsoon trough, while moderate to fresh southerly winds will be 
south of the trough axis. Seas will be generally 5-7 ft. These 
general conditions will prevail through the rest of the week. 
Long period cross-equatorial S to SW swell will build seas to 8 
to 9 ft south of 05N and east of 120W by Thursday.

$$ 
Mundell