Eastern Pacific Tropical Weather Discussion

449
AXPZ20 KNHC 180943
TWDEP 
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Fri Sep 18 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 0600 UTC surface analysis and satellite imagery through
0920 UTC.
...SPECIAL FEATURES...
A tropical wave extends from 07N to 17N with axis near 117W and 
low pressure of 1009 mb near 12N117W (Invest EP98). The wave is 
moving westward at about 10 kt. Satellite imagery reveal 
scattered moderate to strong convection from 08N to 17N between 
112W and 124W. Environmental conditions appear conducive for 
additional development of this system, and a tropical depression 
is likely to form this weekend as it moves westward at 10 to 15 
kt across the western part of the East Pacific and into the 
central Pacific basin. There is a medium formation chance through
48 hours and high formation chance through 7 days.
Please refer to the latest NHC Tropical Weather Outlook at 
website: www.hurricanes.gov for more details.
...TROPICAL WAVES...
A tropical wave extends from 05N to 17N with axis near 101W, 
moving westward at around 10 to 15 kt. Scattered moderate to 
isolated strong convection is seen from 04N to 19N between 90W 
and 110W. The environmental conditions of the tropical wave, 
which is moving across the Guerrero, Mexico offshore waters is 
conducive for gradual development of this system, and a tropical 
depression is likely to form late this weekend or early next week
while it moves gradually northwestward and then northward off 
the coast of southwestern Mexico. There is a low formation chance
through 48 hours and high formation chance through 7 days.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough axis extends from 09N84W to 06N1O6W to 
15N128W. Aside from the convection associated with the tropical 
waves and former TD15-E, scattered moderate to strong convection
is from 02N to 08N between 77W and 91W.
...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 
strong to near-gale force N to NE gap winds across the Gulf of 
Tehuantepec. Seas are 7 to 8 ft. A tropical wave moving across 
the Guerrero offshore waters is producing disorganized showers 
and thunderstorms over that region. Surface ridging west of the 
Baja California offshores is supporting moderate to fresh 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 continue to pulse in Tehuantepec at
fresh to strong speeds through Sat. The environmental conditions
of the tropical wave moving across the Guerrero offshores is 
conducive for gradual development of this system, and a tropical 
depression is likely to form late this weekend or early next week
while it moves gradually northwestward and then 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 midweek. Otherwise, moderate to fresh NW winds will persist 
along the Baja Peninsula offshores, reaching strong speeds at 
night today and Mon. 
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, 
AND WITHIN 750 NM OF ECUADOR...
Fresh to strong NE to E winds prevail across the Gulf of 
Papagayo extending downstream to near 90W. Moderate easterly
winds from this gap event are affecting the outer offshores El
Salvador and Guatemala. Moderate or weaker winds prevail elsewhere,
except for moderate to fresh N winds in the Gulf of Panama 
extending to about 07N. Seas across the offshores are moderate 
in SW 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 Fri, then pulsing to 
moderate to fresh thereafter. Moderate winds and seas will 
prevail elsewhere.
...REMAINDER OF THE AREA...
A 1008 mb low, remnant of Tropical Depression Fifteen-E is 
located near 17N134W. Fresh to strong northeast to east winds 
are within 480 nm northern semcircle of the low. Seas are 7 to 
10 ft with these winds. Satellite imagery shows scattered 
moderate isolated strong convection from 07N to 21N between 124W 
and 140W. Moderate to fresh NE to E winds and rough seas to 9 ft 
are within 210 nm northern semicircle of a 1009 mb low associated
with Invest EP98. Elsewhere, winds are moderate or weaker and
seas are moderate, except rough in the vicinity of EP98.  
For the forecast, see the Special Features and the Tropical Waves
Section. Otherwise, environmental conditions appear only 
marginally conducive for some development of the remnants of
TD 15-E as it moves gradually westward, remaining east-southeast
of the Hawaiian Islands.