766
AXPQ20 PGUM 030014
TWDPQ

Tropical Weather Discussion
National Weather Service Tiyan GU
1014 AM ChST Wed Dec 3 2025

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 AND MONSOON DISTURBANCES...
Invest 93W from JTWC, currently located near 14N134E, continues
it`s struggle to organize, currently rated as having a low chance
for development. With that said, the system has shown attempts to
develop more robust convection at times, with improved poleward
outflow aloft. This system is expected to continue to slowly
organize the next few days. Similar to yesterday, most convection
is located across the eastern half of the circulation. This is
expected to continue the next few days, at which time it`ll have
exited Guam`s AOR which ends at 130E.

...OTHER WEATHER SYSTEMS...

NEAR EQUATORIAL TROUGH...
The NET enters Guam`s AOR at 8N130E and extends to south of Yap at
8N138E, where it turns southeast, passing through a col near
3N143E, before ending at EQ147E. Most of the more intense
convection is found south and west of the NET, where locally heavy
rainfall is occurring given cloud top temperatures eclipsing -90
deg. C, indicating tops near or over 60,000 feet tall. With that
said, additional convection is also found across Koror and to a
lesser extend Yap, as both locations are located within the inflow
region of 93W. Here, scattered to locally numerous showers and
isolated thunderstorms are affecting Koror and surrounding areas,
with diminished coverage and intensity found near Yap. As 93W
exits Guam`s AOR, the NET is expected to dissolve by the weekend.

TRADE-WIND TROUGHS...
The first subtle trade-wind trough is exiting Chuuk, extending
north-northeast from 4N148E to 8N150E. Numerous showers and
isolated thunderstorms are accompanying this feature, which will
move off to the west over the next few days with a similar
convective coverage expected.

Farther east, the next trough is located between Pohnpei and
Chuuk, stretching north-northwest from 3N157E to 9N154E. Scattered
showers and isolated thunderstorms are occurring along and just
east of this feature, which also will move west the next few days
with a similar convective behavior expected.

Finally, a developing trough stretches from 3N177E to 8N175E. This
feature lacks any convection associated with it, but it denotes
the leading edge of an ITCZ attempting to rebuild. This feature
will continue west the next few days, possibly allowing convection
near the Date Line to expand west as well.

OTHER SYSTEMS...
A shear line continues to settle south, entering Guam`s AOR near
16N180, extending west to 15N150, where it curls north-northeast
before ending near 23N150E. Mostly cloudy skies and numerous
showers are found along and just north of the shearline from 155E
to the Date line, with clouds and shower coverage decreasing along
the western "tail" of this feature. This feature is expected to
continue to slowly settle south and gradually lose definition over
the next few days.

...ITCZ...
An ITCZ is observed east of 177E, between 4N and 8N. Here, modest
convergence is fostering widely-scattered shallow shower
development. However, moisture is pooling along the trough and
more so eastward across the Date Line. Cross-equatorial flow and
convergence is also stronger east of the Date Line. However, this
is where it looks to stay as the models show only a modest ITCZ
signature maintaining itself near its current location, possibly
expanding west to Majuro or just beyond there. However, GFS GDI
indices struggle to get into the low 30s, with the ITCZ looking to
settle south by the weekend to between the equator and 4N.

$$

Doll