154
AXPQ20 PGUM 050112
TWDPQ

Tropical Weather Discussion
National Weather Service Tiyan GU
1112 AM ChST Sat Sep 5 2026

Tropical Weather Discussion for the Western North Pacific between
the Equator and 25N from 130E to 180. The following information is
based on recent satellite imagery/data, weather observations, radar,
and meteorological analysis.

...SPECIAL FEATURES...

TROPICAL CYCLONES...
Tropical Depression 23W is located near 26N136E, about 330 miles
west-northwest of Iwo-To. As of 700 AM ChST this morning, 23W was
moving north-northwest at 20 mph. Its maximum sustained winds near
its center was 35 mph, which prompted its change in status from a
tropical storm to a tropical depression earlier this morning.
Maximum significant wave height is 15 feet near its center. 23W is
expected to maintain this intensity as it continues moving north-
northwest over the next day before gradually decreasing as it
nears the southern main islands of Japan. 23W`s current location
is outside of our Area of Responsibility (AOR).

For more information please refer to bulletins from the Joint
Typhoon Warning Center under WMO header WTPN32 PGTW and from the
National Weather Service under WMO header WTPQ32 PGUM.

...OTHER WEATHER SYSTEMS...

MONSOON TROUGH...
The monsoon trough enters our AOR from TD 23W near 25N136E,
extending southeast through a col located north-northeast of the
Marianas. From there, the trough continues south-southeast towards
eastern Micronesia, passing through an embedded circulation
centered near 8N163E before exiting the Date Line to the east
around 10N. An area of convergence between the westerlies and the
circulation is producing scattered to numerous showers and
isolated thunderstorms west and across Pohnpei. To the east of the
Marianas, westerly convergence buckling against the previously
mentioned col is generating a line of numerous showers and
scattered thunderstorms spanning from 21N150E to 13N152E. The
monsoon trough is expected to remain unchanged in intensity,
possibly shifting south over eastern Micronesia this weekend.

SURFACE TROUGHS...
A surface trough extends southward from the embedded circulation
near 8N163E to the Equator around the same longitude. As of
this morning, showers and thunderstorms are scarce as drier air
downstream of the circulation is inhibiting initiation. However,
with daytime heating, rainfall across Kosrae and to the south
should not be ruled out. This surface trough should generate more
convection and showers as it follows the circulation moving west
over the next day or two.

TRADE-WIND TROUGHS...
A couple of trade-wind troughs are observed in our AOR. One
is oriented from the southwest to the northeast from 18N156E to
25N160E, where it exits our AOR. Scattered showers and isolated
thunderstorms span about 75 miles from the trough axis. This
trough is expected to remain near its position and intensity over
the next day or so.

The second trade-wind trough extends from 10N168E north to
19N169E. An area of convection and showers is located north of
Kwajalein, just downstream of the trough. Elsewhere, partly cloudy
skies of cumulus clouds are advecting with the trades. Over the
next few days, this trough will gradually move west with little
to no change in intensity.

$$

Mesa