000
AXPZ20 KNHC 281002
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Mon Aug 28 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 0600 UTC surface analysis and satellite imagery through
0945 UTC.

...SPECIAL FEATURES...

Tropical Storm Irwin is centered near 17.6N 123.0W at 28/0900
UTC, moving west-northwest at 9 kt. Estimated minimum central
pressure is 997 mb. Maximum sustained wind speed is 35 kt with
gusts to 45 kt. Latest satellite imagery shows small clusters of
scattered moderate to isolated strong convection within 90 nm of
the center in the E semicircle. A large area of numerous 
moderate to isolated strong intensity is present well to the east
of the system center from 15N to 20N and between 117W-119W. Seas
peaking to 15 ft are within 90 nm of the center in the NE 
quadrant. Seas to around 12 ft are within 30 nm of the center in 
the SE quadrant and within 120 nm of the center in the NE 
quadrant. Irwin is forecast to turn toward the west by early 
tomorrow morning. A continued westward motion is forecast for the
next several days. Little change in strength is forecast during 
the next few days. Irwin is forecast to become a remnant low by 
the end of the week, but this transition could come sooner.

Please read the latest HIGH SEAS FORECAST 
issued by the National Hurricane Center at website - 
https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest NHC
Forecast/Advisory and Public Advisory at www.hurricanes.gov for 
more details.

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

The monsoon trough axis extends from northwest Colombia to 
central Costa Rica, and continues to 10N85W to 13N99W to
16N110W. It then resumes southwest of Tropical Storm Irwin near 
10N125W to 08N132W to 08N140W. Scattered moderate to isolated
strong convection is from 05N to 09N between 87W-98W.

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

Surface ridging extends toward the Baja California Peninsula  
anchored by a 1023 mb high pressure center that is north of the 
area near 33N133W. The pressure gradient between this high and 
lower pressure over Mexico is supporting mostly gentle to 
moderate N to NW winds, with fresh winds near the coast north of 
Punta Eugenia. Seas are in the range of 4-6 ft due to mainly 
long-period northwest swell that is propagating through the 
offshore waters north of Punta Eugenia. Subsiding seas currently 
peaking to 8 ft as a result of Tropical Storm Irwin are present 
from 16N to 20N between 116W-119W. Elsewhere, gentle to moderate
winds prevail over the southwest Mexican offshore waters along 
with seas of 4-6 ft due to long-period south swell. Winds in the 
Gulf of California are light to gentle along with seas to 3 ft, 
except higher seas of 4-6 ft from the long-period south are near 
the southern tip of Baja California.

For the forecast, moderate to fresh NW winds off Baja California
north of Cabo San Lazaro will persist through mid- week. 
Northerly swell will raise seas to around 8 or 9 ft north of 
Punta Eugenia by Tue, then subside Thu evening. 

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

Light to gentle south to southwest winds prevail across most of 
the offshore waters N of 02N with seas to 4 ft in long-period
south to southwest swell. In the Ecuador and Galapagos Islands 
offshore waters, moderate to fresh south winds with seas of 4-6 
ft due to long-period south swell are noted. 

For the forecast, gentle to moderate south to southwest winds 
and moderate seas will continue between the coast of Ecuador and 
the Galapagos Islands through Thu night. By Wed, an increase of 
southerly swell and seas to 8 ft could impact the Galapagos 
Island offshore waters. Elsewhere, light to gentle variable winds
will prevail through most of the week with slight to moderate 
seas in southwest swell. 

...REMAINDER OF THE AREA...

Please see the Special Features section for details on Tropical 
Storm Irwin.

The pressure gradient between surface ridging north of about 20N
and lower pressures associated with Tropical Storm Irwin and low
pressure embedded in the monsoon trough west of 140W is 
maintaining moderate to fresh north to northeast winds mainly 
north of the monsoon trough to 23N and west of 115W, except for 
an area of fresh to strong northeast to east winds in the far 
western part of the area from 10N to 12N west of 138W. Seas 
associated with the low west of 140W are 8-9 ft. Elsewhere, seas 
are 5-7 ft. Gentle to moderate northeast to east winds and slight
to moderate seas remain north of 15N and west of 125W. Gentle to
moderate southwest winds are elsewhere south of the monsoon 
trough with seas of 5-8 ft.

For the forecast, Tropical Storm Irwin will maintain intensity 
as it moves to near 18.0N 124.3W this afternoon, to near 18.4N 
126.9W late tonight, to near 18.4N 129.7W Tue afternoon, then
weaken to a tropical depression near 18.3N 132.4W late Tue night,
become a remnant low and move to 18.4N 134.7W Wed afternoon, and
to near 18.6N 136.6W late Wed night. The low pressure west of 
140W will continue to support fresh to strong northeast to east 
winds and rough seas to 9 ft over the far western tropical waters
for a few more hours. Northerly swell will propagate through
the open waters W of the Baja California offshore waters tonight
through at least Thu night. Southerly swell in the far southern 
waters could see 8-9 ft seas by Mon night. This swell area could 
travel as far north as 05N between 92W-120W through late Thu.

$$
Aguirre