412 
AXPZ20 KNHC 190400
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Sat Sep 19 2026

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 0000 UTC surface analysis and satellite imagery through
0350 UTC.

...SPECIAL FEATURES...

Western East Pacific: Low pressure, Invest EP98, is centered near
11N118W with a pressure of 1009 mb. This feature is part of a rather 
broad area of cyclonic circulation. satellite imagery exhibits 
scattered moderate to isolated strong convection from 05N to 17N
between 115W and 125W. Environmental conditions are conducive 
for development, and a tropical depression is likely to form this
weekend as it moves westward at 10 to 15 mph across the western 
East Pacific. The low has a high chance of tropical cyclone 
formation through the next 48 hours and the next 7 days.

South of Southwestern Mexico: A tropical wave, Invest EP99, has its 
axis extending from near 18N107W to 04N107W, with low pressure 
of 1009 mb, near 08N106W. This feature is part of a broad area 
low pressure that is located about 700 nautical miles south- 
southwest of the southwestern coast of Mexico. satellite imagery 
depicts scattered moderate to isolated strong convection from 
05N to 15N between 100W and 110W. Environmental conditions are 
conducive for development, and a tropical depression is likely to
form late this weekend or early next week while it moves 
generally northward off the coast of southwestern Mexico. This 
system has a medium chance of tropical cyclone formation through 
the next 48 hours and a high chance of development within the 
next 7 days.

Please refer to the latest NHC Tropical Weather Outlook at 
website: www.hurricanes.gov for more details on these Invests.

...TROPICAL WAVES...

A tropical wave in the western Caribbean Sea with axis near 81W 
extends southward across Panama and its offshore waters. It is 
moving westward near 15 kt. Numerous moderate to strong 
convection is from 02N to 10N between 77W and 85W.

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

The monsoon trough axis extends from 08N83W to 08N100W to 
12N120W to 17N137W to 15N140W. Scattered moderate to isolated 
strong convection is from 03N to 13N between 90W and 100W, and
from 09N to 21N between 125W and 135W. 

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

The pressure gradient between a ridge over the Gulf of America 
and the eastern extension of the Pacific monsoon is supporting 
fresh to strong N gap winds across the Gulf of Tehuantepec. Seas
with these winds are 6 to 8 ft. Scattered showers are over the 
offshore waters between Chiapas and Oaxaca due to a broad area of
low pressure and the monsoon south of the region. The gradient 
related to high pressure west of the Baja California offshores
and low pressure along western Mexico is supporting fresh to
locally strong NW winds N of Cabo San Lazaro. Moderate or weaker
winds are elsewhere along with moderate seas, except for slight 
seas in the Gulf of California. 

For the forecast, winds will pulse to fresh to strong speeds in 
the Gulf of Tehuantepec tonight becoming moderate N to NE winds 
Sat afternoon. Fresh to strong NW winds offshore Baja California
will diminish Sat afternoon. Northwest winds over these waters 
are expected to briefly reach fresh speeds Mon night into Tue. 
Otherwise, the environmental conditions of Invest EP99, near 
08N106W, are conducive for development and a tropical depression
is likely to form late this weekend or early next week while it 
moves generally northward off the coast of southwestern 
Mexico. Regardless of development, this system is forecast to 
bring fresh to strong winds and moderate to rough seas to the 
Michoacan and Jalisco offshores Tue night into the middle part of
next week.

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

Moderate to fresh NE to E winds are across the Gulf of Papagayo 
extending downstream to near 88W. Moderate or weaker winds 
prevail elsewhere, except for strong to gusty winds likely
ongoing across the W Panama and Costa Rica offshores due to
strong convective activity associated with a tropical wave. Seas
over the offshore waters are of moderate state due to a long- 
period southwest swell.

For the forecast, the pressure gradient between the ridge north 
of the area and the eastern Pacific monsoon will support pulsing 
fresh to occasionally strong easterly winds and moderate to rough
seas across the Papagayo region into early Sat, then pulsing to 
moderate to fresh speeds through early Sun. Moderate winds and 
seas will prevail elsewhere.

...REMAINDER OF THE AREA...

The remnant 1008 mb low of former Tropical Depression Fifteen-E 
is located near 17N137W. A tight gradient between the low and 
high pressure of 1024 mb to its north is bringing fresh to 
strong northeast to east winds over the waters from 16N to 26N 
west of 124W. Seas are 6 to 9 ft within this area of winds. 
satellite imagery shows scattered moderate isolated strong 
convection from 10N to 21N between 126W and 135W. Elsewhere, 
winds are moderate or weaker for the most part and seas are of 
moderate state, except for rough state seas in the vicinity of 
Invest EP98. 

For the forecast, see the Special Features section. Otherwise, 
environmental conditions appear conducive for some development 
of this system next week as it moves westward to west-
southwestward, and a tropical depression could form well to the 
south or southeast of the Hawaiian Islands by the middle to 
latter part of next week.

$$
Ramos