204
AXPQ20 PGUM 210052
TWDPQ

Tropical Weather Discussion
National Weather Service Tiyan GU
1052 AM ChST Fri Nov 21 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...

None.

...OTHER WEATHER SYSTEMS...

NEAR EQUATORIAL TROUGH...
The NET has lifted north and now stretches from 5N130E to near
5N150E, with westerly flow having developed south of there. The
GFS wind fields suggest a circulation is trying to form near
3N138E, but visible imagery indicates just westerly flow there.
The other models show no development either, with none of the
models indicating westerly flow to the extent visible on today`s
satellite imagery. This leads to a low confidence forecast, but
in general typically a circulation will develop along the NET, so
we do expect this to occur, especially given upper-level high
pressure development near Guam expected during the next 48 hours.

SURFACE TROUGHS...
A surface trough extends from 5N138E to Yap, ending there
(9N138E). Numerous showers and scattered thunderstorms are
occurring along this feature. This will continue as the trough
moves west the next few days.

Another trough much further east stretches from Nukuoro near
4N155E to Pohnpei (7N158E). However, convection is localized to
near Pohnpei as convergence interacts with a pocket of moderate
divergence aloft, with this divergence located east of an
inflection point near 5N150E. This trough should remain
convectively active as it heads west and interacts with the NET in
48 to 72 hours.

TRADE-WIND SURGE...
The trade-wind surge has expanded further today, and changed
orientation to a west-southwest through east-northeast alignment.
Most of the stronger winds, on the order of 20 to 30 knots
(sustained) are centered between 8N and 22N (farthest south west,
farthest north east near the Date Line). Seas of 8 to 11 feet are
common underneath this trade-wind surge. This feature is expected
to gradually weaken through the weekend, as high pressure north-
northeast of the region continues to move away, allowing the
pressure gradient to weaken.

OTHER SYSTEMS...
An upper low is centered just west of the Rota Channel. Widely-
scattered convection is occurring around the periphery of this
low. This feature looks to dissolve during the next 24 to 36
hours, as an upper-level area of high pressure develops near Guam.

...ITCZ...
The ITCZ remains fragmented and weak, with embedded troughs being
the only focus for convection. One such fragment extends from
Chuuk eastward to near Pohnpei, with the other fragment crossing
the Date Line. This second feature has no appreciable convection,
just streamline convergence to signify its presence. In general,
the ITCZ looks to remain weak and fragmented over the next few
days.

$$

Doll