000
AXPZ20 KNHC 071531
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1356 UTC Fri Jul 7 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 broad low pressure area embedded in the Monsoon Trough is 
centered near 11.5N110W and moving W-NW at about 10 kt. 
Scattered moderate and isolated strong convection is noted from 
08N to 15N between 105W and 118W. Latest infrared satellite 
imagery shows cyclonically curved convective bands around the 
circulation center in an area of low vertical shear. This 
environment will remain favorable for the low to strengthen, and
it is likely to become a tropical cyclone within the next day or
so. A recent 07/0454 UTC ASCAT scatterometer pass indicated 
southwesterly 20-25 kt monsoonal flow within 180 nm in the SE 
quadrant of the low. This, in conjunction with long period 
cross-equatorial, swell is generating an area of 8 to locally 10
ft seas. This system has a high chance for formation within the 
next 48 hours.

...TROPICAL WAVES...

A tropical wave extends its axis from the Yucatan Peninsula to
the EPAC waters near 13N89W, moving west at 15-20 kt. Isolated
showers are observed along the wave's axis mainly over the
Yucatan Peninsula.

A tropical wave extends its axis from inland Mexico near 22N101W
to 13N100W, moving west at 10-15 kt. Scattered moderate convection
is from 14N to 17N between 99W and 103W.

A tropical wave extends its axis from 21N126W to a 1011 mb low 
near 18N127W to 14N127W, moving west at 10-15 kt. Isolated
showers are observed from 15N to 19N between 126W and 130W. 

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

The Monsoon Trough extends from 09N84W to 09N92W to 12N102W then
from 11N107W to 10N114W to 13N125W to 11N138W. ITCZ from 11N138W
to beyond 10N140W. Scattered moderate convection is from 06N to 
13N between 84W and 100W, and from 09N to 13N and west of 123W.

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

A ridge extends across the waters W of Baja California from
28N128W to 20N114W. Gentle to moderate N-NW flow prevails W of 
the Baja California peninsula, moderate to fresh N winds in the 
Gulf of Tehuantepec, and light to gentle winds across the Gulf 
of California. Seas are ranging 4-6 ft in the open waters W of 
Mexico, with 1-3 ft seas in the Gulf of California. Nocturnal 
winds will pulse to a max of 20 kt each night in the Gulf of 
Tehuantepec, then 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 for the remainder of this week. Gentle to 
moderate southerly winds are expected S of the Monsoon Trough. 
Long period cross-equatorial S to SW swell and seas to 6-8 ft W 
of Colombia and Ecuador will continue gradually subsiding today
and into the weekend.

REMAINDER OF THE AREA...

See the Special Feature section for more information on the low 
centered near 11.5N110W. Outside of this area, gentle to moderate
trade winds will prevail N of the Monsoon Trough, while moderate
to fresh southerly winds will be S of the trough axis. Seas will
be generally 5-7 ft. These conditions are expected to continue 
through the weekend.

$$

ERA