000
AXPZ20 KNHC 240354
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Thu Aug 24 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 0000 UTC surface analysis and satellite imagery through
0300 UTC.

...SPECIAL FEATURES...

South of Southern Mexico: An elongated area of showers and 
thunderstorms located several hundred miles south of the coast of
southern Mexico is associated with a trough of low pressure. 
Environmental conditions appear favorable for gradual development
of this system, and a tropical depression is likely to form 
within the next two to three days while it moves slowly to the 
northwest or north-northwest. Currently, this system has a medium
chance of tropical cyclone formation through 48 hours, and a 
high chance through 7 days. Please, refer to the latest NHC 
Tropical Weather Outlook at www.hurricanes.gov for more details. 

...TROPICAL WAVES...

A tropical wave is along 105W north of 05N, moving westward 
around 10 kt. Scattered moderate to isolated strong convection is
noted ahead of the wave axis along the monsoon trough from 09N 
to 11N between 105W and 108W. 

A tropical wave is along 118W, from 04N to 16N moving westward 
at 10 to 15 kt. Scattered moderate convection is observed from 
12N to 14N between 116W and 119W.

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

The monsoon trough axis extends from 12N84W to 1008 mb low
pressure located near 10N99W to 1007 mb low pressure near 11N111W
to 09N135W. The ITCZ extends from 09N135W to beyond 09N140W. 
Scattered moderate convection is along the coast of El Salvador,
and from 13N to 15N between 95W and 98W.

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

Ship observations confirm moderate to fresh NW winds and 5 to 7
ft combined seas off Baja California, between the subtropical 
ridge to the west and troughing over northwest Mexico. Farther
south, fresh to strong gap winds are noted again over the Gulf of
Tehuantepec. Gentle breezes dominate the remainder of the area,
with moderate combined seas over open waters in mostly SW swell.
Scattered showers and a few thunderstorms are noted off Cabo 
Corrientes, and onshore near Acapulco. 

For the forecast, the ridge will continue the dominate the 
offshore waters of Baja California generating mainly gentle to 
moderate NW winds, except for moderate to fresh winds are 
expected at night between Cabo San Lazaro and Punta Eugenia. 
Northerly gap winds will continue to pulse mainly at night across
the Gulf of Tehuantepec into Fri. Looking ahead, an elongated 
area of showers and thunderstorms located several hundred miles 
south of the coast of southern Mexico is associated with a trough
of low pressure. Environmental conditions appear favorable for 
gradual development of this system, and a tropical depression is 
likely to form within the next two to three days while it moves 
slowly to the northwest or north-northwest. Currently, this 
system has a medium 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...

The monsoon trough has started to lift northward, allowing
pockets of fresh to occasionally strong SW winds along locally
rough seas to cover the offshore waters of Costa Rica and
Nicaragua. Light to gentle breezes persist elsewhere with
moderate SW swell. Scattered showers and thunderstorms are noted
over the coast of El Salvador.

For the forecast, the active monsoon trough will continue to 
support fresh to occasionally strong SW winds and locally rough 
seas off Costa Rica, Nicaragua and El Salvador through late Thu 
as the low pressure moves northward inland. The moist SW flow may
support heavy rainfall across coastal portions of Costa Rica, 
Nicaragua, and El Salvador through late Thu. Please check with
local weather service offices for more information. These 
conditions 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. 

...REMAINDER OF THE AREA...

1030 mb high pressure is located well NW of the area near 
40N146W. The associated ridge extends across the northern 
forecast waters, mainly north of 20N and west of 120W. The 
pressure gradient between the ridge and lower pressure in the 
vicinity of the monsoon trough supports and area of moderate to 
fresh winds from 10N to 15N between 120W and 130W. A
scatterometer satellite pass indicated a small area of strong NE
winds embedded in this area near 14N121W just ahead of the
tropical wave in an area of showers and thunderstorms. Gentle to
moderate winds are elsewhere under the influence of the ridge 
with seas of 5 to 7 ft primarily in northerly 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. Looking ahead, an
area of low pressure could form well south-southwest of the southern
tip of the Baja California Peninsula within the next day or two.
Environmental conditions are expected to be conducive for some 
gradual development of this system later this week and this weekend
while it moves west-northwestward between 110W and 130W in the 
tropical eastern Pacific.

$$
Christensen