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Eastern North Pacific Tropical Weather Discussion


000
AXPZ20 KNHC 290855
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Tue Jul 29 2025

Tropical Weather Discussion for the eastern Pacific Ocean from
03.4S to 30N, east of 120W including the Gulf of California, and
from the Equator to 30N, between 120W and 140W. The following
information is based on satellite imagery, weather observations,
radar, and meteorological analysis.

Based on 0600 UTC surface analysis and satellite imagery through
0830 UTC.

...SPECIAL FEATURES...

Western East Pacific Low (EP98): The area of low pressure located
around 1500 miles east-southeast of the Hawaiian Islands has not 
changed. At this time, the low pres is analyzed near 10N135W,
1008 mb. Strong winds prevail over the N semicircle of the low, 
with rough seas. Environmental conditions appear marginally 
conducive for some development of this system, and a tropical 
depression or tropical storm could form during the next day or 
two as it moves generally westward around 10 kt and enters the 
Central Pacific basin around midweek. There is a medium chance of
development of this system within the next 48 hours.

South of Southwestern Mexico (EP99): A large area of 
disorganized showers and thunderstorms located a few hundred 
miles south of the southern coast of Mexico is associated with a 
trough of low pressure. Rough seas prevail in this area. 
Environmental conditions appear conducive for development, and a 
tropical depression is likely to form during the next couple of 
days while the system moves west- northwestward around 15 kt, 
remaining well offshore of the southwestern coast of Mexico. 
There is a high chance of tropical formation within the next 48 
hours. 

Refer to the latest NHC Tropical Weather Outlook at 
www.hurricanes.gov for more details about these invests.

Tehuantepec Gale Warning: The pressure gradient between high 
pressure over Mexico, and lower pressure near the monsoon trough
and EP99 described above, is inducing gale force winds in the
Tehuantepec region. Rough seas will prevail with these winds. 
These conditions are expected through the afternoon hours, then 
strong winds will pulse at night through the week. Please refer
to the latest High Seas Forecast issued by the National Hurricane
Center at website- https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml
for details.

...TROPICAL WAVES...

A tropical wave is analyzed along 99W, and N of 04N, moving W at
5 to 10 kt. Scattered moderate convection is noted from 07N to 
16N between 96W and 105W.

A tropical wave is analyzed near 120W from 03N to 20N, moving 
westward around 5 to 10 kt. Scattered showers are noted in the
vicinity of the wave axis.

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

The monsoon trough extends from 09N84W to 09N108W to 12N118W to
09N140W. Scattered moderate convection is noted from 07N to 15N 
and E of 114W, and scattered showers prevail from 06N to 13N and
W of 120W.

...OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

See Special Features Section above for information on low
pressure developing SW of the Gulf of Tehuantepec that has the
possibility of tropical formation this week.

Surface troughing extends through the Gulf of California, and 
high pressure prevails over the Baja California waters. The 
pressure gradient between these features is leading to fresh NW 
winds offshore of Baja California north of Cabo San Lazaro. 
Moderate seas are also present in this region. Strong to gale 
force N gap winds and rough seas have developed in the Gulf of 
Tehuantepec, as a tightening pressure gradient prevails between 
troughing over the Yucatan Peninsula and high pressure over east-
central Mexico. Elsewhere, moderate or weaker winds prevail over
the remainder of the Mexico offshore waters. Moderate seas in 
mixed S and NW swell are noted offshore of southern Mexico, with 
slight seas in the Gulf of California. 

For the forecast, strong to gale force winds and rough seas will
continue in the Gulf of Tehuantepec through this afternoon, then
winds will pulse to strong through the week as pressure gradient
tightens as a result of the low pressure forming to the SW. 

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

Fresh E winds prevail in the Gulf of Papagayo as the pressure
gradient between higher pressure to the northern and low pressure
to the south funnels gap winds across Central America into the
Pacific. South of the monsoon trough, mainly gentle S to SW 
winds are occurring. Moderate seas prevail over the Central and 
South American waters.

For the forecast, fresh E gap winds and moderate seas will 
prevail in the Gulf of Papagayo as an area of low pressure 
develops and strengthens to the west. After a brief lull, pulsing
fresh to strong winds look to redevelop in the Gulf of Papagayo 
late this week. 

...REMAINDER OF THE AREA...

Refer to the Special Features section above for information on
two areas of possible tropical development this week. 

Moderate to fresh NE to E winds prevail north of the monsoon 
trough to 25N as ridging prevails to the north. Elsewhere, a 
weak pressure gradient in the northern waters, north of 25N, is 
leading to light to gentle winds and slight to moderate seas. 

For the forecast, moderate to fresh N to NE winds and moderate 
seas are expected north of the monsoon trough this week as high 
pressure builds to the north. 

$$
ERA