487
AXPQ20 PGUM 290112
TWDPQ

Tropical Weather Discussion
National Weather Service Tiyan GU
1112 AM ChST Thu Oct 29 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...
As of 7:00 AM ChST this morning, Typhoon In-fa was located over
the open ocean near 16N156E, about 625 miles north-northeast of
Chuuk and 735 miles east-northeast of Guam, and moving west at 15
mph. Maximum sustained winds have decreased to 140 mph and are
expected to remain this intensity over the next day or so. In-fa
is forecast to make a slight turn to the west-northwest with an
increase in forward speed through Friday, taking its center over
or near Agrihan Friday evening. Himawari satellite imagery reveals
an approximate eye width of 50 miles. Convection is concentrated
along its west to southeast peripheries, with significant wind
shear to its north and northeast limiting convective activity. The
latest scatterometry pass shows an almost asymmetric wind field,
with typhoon-force winds extending up to 50 miles to the north and
30 miles to the south. Tropical storm force winds reach up to 140
miles from the center to the north and about 120 miles elsewhere.
In-fa is forecast to continue tracking towards the far northern
Marianas over the next day or so.

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...
The monsoon trough enters Guam`s Area of Responsibility (AOR)
around 8N130E turning to the north-northeast through an embedded
broad circulation north of Koror, Palau and northwest of Yap
Island. Convergence along the northern edge of this circulation is
producing a short line of convection with widespread cloud cover
and scattered locally heavy showers over open waters. The trough
then continues south of Guam where it merges with an existing
trade-wind trough to the west before becoming wrapped into Typhoon
In-fa`s inflow along its southern peripheries. Patchy showers and
cloud cover exists near the trough axis along this segment of the
monsoon trough, with significant convective development south of
Guam. From In-fa, the monsoon trough shifts slightly north-
northeast before dipping to the south-southeast around 12N166E,
finally exiting the AOR around 10N180. Widespread cloud cover,
numerous showers, and isolated convection is apparent from
northeast of Kwajalein to Majuro Atoll. The monsoon trough looks
to remain nearly stationary with lulls in shower activity across
various areas over the next few days.

TRADE-WIND TROUGHS...
A trade-wind trough begins around 20N135E and continues south-
southeast where it merges with the monsoon trough southwest of Guam
around 13N140E. Patchy cloud cover and scattered showers extend from
the trough axis up to 100 miles. Isolated thunderstorms and numerous
showers are evident south of Guam where the aforementioned merging of
the troughs occur. This trade-wind trough is expected to move south-
southwest over open waters before dissipating over the next day or
so.

OTHER SYSTEMS...
A fragmented shear line enters the AOR around 20N130E and continues
north-northeast, exiting around 25N147E. Cloud cover extends up to
200 miles from the line axis, but remains sparse and patchy, with
isolated to scattered showers expanding across the same area. This
shear line is expected to continuing dissipating over the next day
or two as In-fa approaches the feature.

$$

Mesa