069
AXPQ20 PGUM 170035
TWDPQ

Tropical Weather Discussion
National Weather Service Tiyan GU
1035 AM ChST Thu Sep 17 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 Storm Dujuan (24W) continues to move away from the
Marianas this morning, as it`s forward speed has increased. The
system is still fighting some dry air along it`s western flank,
giving it an asymmetric look at first glance. Seas near the LLCC
have increased to 18 feet.

At 700 AM CHST...2100 UTC...the center of Tropical Storm Dujuan
was located near Latitude 18.4 degrees North and Longitude
149.5 degrees East. Dujuan is moving north-northeast at 13 mph.
It is expected to make a turn toward the northwest with an
increase in forward speed through Friday.

Maximum sustained winds have increased to 45 mph. Tropical storm
force winds extend outward from the center up to 175 miles to the
south and up to 70 miles to the north. A gradual strengthening and
turn to the northwest is anticipated over the next several days.

For more information please refer to bulletins from the Joint
Typhoon Warning Center under WMO header WTPN31 PGTW and from the
National Weather Service under WMO header WTPQ31 PGUM.

...OTHER WEATHER SYSTEMS...

MONSOON TROUGH...
Today, the trough enters Guam`s AOR at 12N130E, and extends
northeast to TS Dujuan. It then dives southeast through a col at
15N160E, before linking up with a quasi-stationary circulation
northeast of Majuro near 9N173E, before exiting the AOR at 10N180.

This pattern is very reminiscent of the synoptic pattern in early
July, which featured a tropical storm lifting north then northwest
towards Japan, after initally departing the northern CNMI heading
northeast. It then had a "Monsoon Tail" that extended southeast
before curling east to a circulation near Majuro, just as the
current pattern shows.

As for convection being tied to the two circulation centers
mentioned above, we do have convection in the form of scattered
showers and thunderstorms along and south of the trough axis from
130E to Dujuan. Isolated to widely scattered showers and a few
thunderstorms also found near Kosrae, as you are in between a ridge
axis to the west and the Majuro low, allowing for good surface
convergence to focus in a narrow corridor there.

As Dujuan pulls away, the expectation is for the monsoon trough
to sink back south while also allowing the Majuro disturbance to
ride along it as it (the Majuro disturbance) moves west,
eventually turning more to the west-northwest with time.

SURFACE TROUGHS...
A surface trough extends north from Dujuan to 25N150E. Scattered
showers and a few thunderstorms are developing along and east of
this feature, and this will likely continue as both Dujuan and the
trough turn northwest over the next few days, exiting the AOR as
they do so.

$$

Doll