000
AXPZ20 KNHC 231559
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Wed Aug 23 2023

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 1200 UTC surface analysis and satellite imagery through
1500 UTC.

...TROPICAL WAVES...

A tropical wave is along 103 north of 05N, moving westward around
10 kt. Scattered moderate to isolated strong convection is noted
on either side of the wave axis from 07N to 16N between 100W and
107W. 

A tropical wave is along 116W, from 04N to 16N moving westward 
at 10 to 15 kt. Scattered moderate to isolated strong convection
is observed from 06N to 15N between 110W and 120W.

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

The monsoon trough axis extends from 10N84W to 11N103W to 
12N116W to 09N132W. The ITCZ extends from 09N132W to beyond 
07N140W. Scattered moderate and isolated strong convection is 
from 06N to 15N between 80W and 126W. 

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

A ridge dominates the offshore waters of Baja California producing
moderate to fresh NW winds, mainly N of Cabo San Lazaro. Seas are
generally 4 to 6 ft. Light to gentle winds are seen in the Gulf 
of California with seas of 1 to 3 ft, except 3 to 4 ft near the 
entrance to the Gulf. Fresh to strong N gap winds are blowing 
across the Gulf of Tehuantepec and downwind to about 14N with
seas to 8 ft. These winds are occurring due to lowering pressure
over the eastern tropical Pacific, along the monsoon trough. 
A weak pressure gradient is supporting gentle breezes elsewhere,
with moderate combined seas primarily in SW swell. 

For the forecast, the northerly gap winds will continue to pulse
mainly at night across the Gulf of Tehuantepec into Fri. Looking
ahead, an elongated trough of low pressure is located several 
hundred miles offshore of the coast of Central America and 
southern Mexico. Environmental conditions appear generally 
favorable for gradual development of this system, and a tropical 
depression is likely to form by this weekend while it moves 
slowly to the northwest or north-northwest. Currently, this
system has a low chance of tropical cyclone formation through 48
hours, and a high chance through 7 days. 

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

A small 1009 mb low pressure area is starting to develop along 
the monsoon trough west of northwest Costa Rica near 10N87W. 
Fresh to strong SW winds are likely ongoing south of the low, 
with fresh SE winds across the Gulf of Papagayo and the coast of 
Nicaragua. Seas are reaching 8 ft near the coast of Costa Rica 
and western Panama in a combination of the fresh SW monsoon flow 
and a component of longer-period SW swell. Scattered showers are 
ongoing in this area. Gentle winds and moderate combined seas are
noted elsewhere in SW swell. 

For the forecast, the active monsoon trough will continue to support
fresh to strong SW winds and rough seas off Costa Rica and Nicaragua
through Thu. These winds and seas will diminish Fri as the monsoon
trough lifts north of the area. Elsewhere, gentle to moderate winds
and moderate seas, primarily in SW swell will prevail. Looking 
ahead, an elongated trough of low pressure is located several 
hundred miles offshore of the coast of Central America and 
southern Mexico. Environmental conditions appear generally 
favorable for gradual development of this system, and a tropical 
depression is likely to form by this weekend while it moves 
slowly to the northwest or north-northwest. Currently, this 
system has a low chance of tropical cyclone formation through 48 
hours, and a high chance through 7 days. 

...REMAINDER OF THE AREA...

The most recent altimeter data indicated seas up to 8 ft near 
30N135W, part of NE swell moving through the area. Farther south,
altimeter data also continues to show 8 ft seas as part of an 
area extending south of 10N and east of 110W, due in part to 
enhanced fresh to strong SW monsoon flow along with a component 
of SW swell. Broad ridging dominates the pattern north of 20N, 
supporting gentle to moderate breezes and moderate combined seas 
in a mix of SW and NW swell. 

For the forecast, fresh to strong SW winds will persist south of
the monsoon trough and east of 120W through Thu. The surface 
ridge should strengthen on Fri into Sun, forcing fresh NE trades 
and seas 6 to 8 ft west of 120W from 10N to 20N.

$$
GR