Tropical Weather Discussion
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AXPQ20 PGUM 230044
TWDPQ

Tropical Weather Discussion
National Weather Service Tiyan GU
1044 AM ChST Sun Feb 23 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...

TRADE-WIND TROUGHS...
There are a few trade-wind troughs seen across the region. The first
is seen over Yap Proper, stretching north from near 8N138E to
12N139E. This trough is interacting with a band of trade-wind
convergence to produce moderate to deep convection to the west of Yap
Proper, with scattered to numerous showers and isolated
thunderstorms in a narrow band between 9N and 12N. This trough will
move west-southwest over the next few days, exiting the region early
in the week.

The second trough is seen south of Pohnpei, stretching southeast
from near 6N156E to 2N161E. Moderate to deep convection with
scattered to numerous showers are seen west of the trough, south of
Pohnpei to well south of Weno, Chuuk. Another weak trough is seen
just east of this trough, near Kosrae extending south-southeast from
near 6N162E to 3N163E. These troughs will continue to move southwest
over the next few days, with convection drifting south of the
equator.

The last trough is found east of the Marshall Islands, extending
south-southeast from 12N177E to 6N180. Only patchy clouds and
showers are associated with this trough. The trough will continue to
move southwest over the coming days with little change in intensity
or convection.

TRADE-WIND SURGE...
A trade-wind surge associated with mid-latitude high pressure
stretches eastward from 130E to just west of the Marshall Islands,
between 5N and 16N. The region is mostly dry associated with this
surge and looks to remain that way over the coming days. The surge is
resulting in fresh to strong winds with some areas seeing near-gale
to gale force gusts. The surge is expected to weaken over the western
portion of the region over the next couple of days and strengthen
east as the high pressure responsible drifts eastward.

OTHER SYSTEMS...
A weakening shear line extends west-southwest across 20N180 to end
east of Palau, south of Yap Proper, near 7N137E. Cloudiness with
patchy showers are found along the shear line east of 165E. The shear
line becomes very diffuse with only patchy cloudiness seen west of
165E. Moderate to fresh winds with strong gusts are found along the
the entire length of the shear line. The feature is expected to
continue to dissipate over the next few days. Little convection is
expected to remain with the shear line.

A band of trade-wind convergence is found north of a shear line,
extending east-northeast from west of Yap Proper, near 10N133E,
across the Marianas to end near 17N152E. Mostly patchy clouds and
convection are found along the convergence band, with moderate to
deep convection found west of Yap Proper where a weak trade-wind
trough is interacting with the convergence. The band of convergence
is expected to weaken over the coming days as the shear line to the
south of it dissipates.

Another band of weak trade-wind convergence is found south of the
Marshall Islands over Butaritari and Tarawa atolls. Patchy showers
are associated with the band of convergence. A weak trade-wind trough
is interacting with the eastern end of the band, but is not producing
more than a few showers. The convergence is expected to weaken over
the coming days, with decreasing convection.

$$

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