Eastern Pacific Tropical Weather Discussion

704
AXPZ20 KNHC 162014
TWDEP 
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Wed Sep 16 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 1800 UTC surface analysis and satellite imagery through
2000 UTC.
...SPECIAL FEATURES...
Gulf of Tehuantepec Gale Warning: The pressure gradient between 
high pressure over southern Mexico and the eastern north Pacific
monsoon trough will support strong to near-gale force N to NE 
gap winds across the Gulf of Tehuantepec through Thu, and will 
reach minimal gale force overnight tonight and briefly Thu night.
Rough seas will accompany these gap winds.
...TROPICAL WAVES...
A tropical wave has been added to the surface map with axis near
99W, from 04N northward to S Mexico. The wave is moving westward
at around 10 to 15 kt. Nearby convection is discussed in the 
ITCZ/monsoon trough section below. An area of low pressure could 
form in association to this wave well offshore of southwestern 
Mexico within the next few days. Environmental conditions appear 
conducive for some gradual development, and this system could 
become a tropical depression early next week while it moves 
slowly northwestward or northward. There is a low chance for 
development in the next 48 hours, and a medium chance for 
tropical cyclone development within the next 7 days. 
The axis of a tropical wave is near 113 from 02N to 17N, moving 
west at 10 to 15 kt. Nearby convection is discussed in the 
ITCZ/monsoon trough section below.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough extends from 09N84W to 07N95W to 15N129W to 
10N140W. Scattered moderate convection is noted from 03N to 10N 
E of 93W, and from 04N to 14N between 97W and 140W.
...OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
Please see Special Features section above for more on a gale 
warning in the Gulf of Tehuantepec. 
Moderate to fresh winds, and moderate seas, are over the 
northern Gulf of California. Gentle to moderate winds and 4-7 ft 
are noted elsewhere, except 1-3 ft in the central and southern 
Gulf.
For the forecast, please see the Special Features section for 
information about the gale warning in the Gulf of Tehuantepec. 
Elsewhere, gentle to moderate breezes and moderate seas will 
persist. 
...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, 
AND WITHIN 750 NM OF ECUADOR...
Fresh to strong easterly winds, and moderate to rough seas, 
prevail across the Gulf of Papagayo region, extending downstream 
to near 90W. Moderate to fresh winds extend downstream from the 
Gulf of Papagayo to the outer offshore waters of El Salvador and 
Guatemala. Elsewhere, moderate or weaker winds and moderate seas 
are noted.
For the forecast, the pressure gradient between a ridge north of
the area and the eastern north Pacific monsoon trough will 
support pulsing fresh to occasionally strong easterly winds and 
moderate to rough seas across the Papagayo region into Thu, then 
pulsing to moderate to fresh thereafter. Moderate winds and seas 
will prevail elsewhere. 
...REMAINDER OF THE AREA...
The remnant low of TD Fifteen-E is centered near 16N129W. 
Scattered showers and thunderstorms remain active in the vicinity
of the low. Fresh to strong winds, and rough seas, supported by 
the pressure gradient between the area of low pressure and the 
subtropical ridge north of the area, cover the waters from 14N to
23N west of 125W. Farther south, cross- equatorial SW swell to 8
ft is reaching as far north as 02N between 115W and 125W. Gentle
to moderate winds and 4-6 ft combined seas in mixed swell are 
noted elsewhere. 
For the forecast, a broad area of fresh to strong NE to E winds
and moderate to rough seas in N swell will persist through the 
remainder of the week from 15N to 25N west of 125W. The 
southerly swell south of 03N will subside below 8 ft by this 
evening.