589
AXPQ20 PGUM 270122
TWDPQ

Tropical Weather Discussion
National Weather Service Tiyan GU
1122 AM ChST Thu Mar 27 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...
A weak near-equatorial trough (NET) extends southeast from the very
disorganized area of vorticity associated with JTWC`s Invest 96W, now
west of 130E, and enters the region near 5N130E and continues along
the equator, ending near 142E. Scattered showers are seen along the
NET, mainly between the equator and 6N, but the overall intensity of
convection has decreased over the last 24 hours as the westerly winds
that extended along the equator are weakening. The NET is expected
to shift west and out of the region by Friday, allowing trade winds
along the equator to extend towards 130E.

TRADE-WIND TROUGHS...
A subtle trade-wind trough is seen west of the northern Marianas
extending from 22N142E to 17N142. Scattered showers are developing
along the trough and become spotty across the northern Marianas
Islands, near and north of Pagan, as they extend along weak
convergence trailing east of the trough. Satellite infrared imagery
shows cloud top temps are around 10C, suggesting showers are shallow
and rainfall is on the lighter side. This trough is expected to
continue west and remain weak as it continues across the open waters
of the Pacific Ocean.

OTHER SYSTEMS...

A line of trade-wind convergence extends along 11N from 130E to
143E, passing north of Palau and across Yap Proper and nearby
islands. Scattered showers are developing along this line, but
showers are heavier west of 136E and are even producing a few
lightning strikes according to the Global Lightning Detection (GLD)
network. This line of trade-wind convergence is expected to shift
west and weaken, shifting showers west of Yap Proper, and staying
north of Palau.

...ITCZ...
Compared to 24 hours ago, the ITCZ and previous convection across
eastern Micronesia have weaken significantly. This morning`s
scatterometer data is showing weaker southeast flow along and just
north of the equator, and previous showers and thunderstorms have
likely stabilized the atmosphere between 2N and 7N. Scattered showers
and isolated thunderstorms are seen mainly across southern Pohnpei
and Chuuk States and the very eastern islands of Yap State, between
2N and 7N from 160E to 143E. East of 160E, showers are much more
spotty to low-end scattered in nature between 2N and 7N, with the GLD
network not detecting any lightning across Kosrae State or the
Republic of the Marshall Islands this morning. Model guidance
suggests the ITCZ will continue to weaken and fragment into a series
of troughs that will push into Yap State, mainly south of 8N, while
weak trade-wind convergence lingering between 2N and 7N of Pohnpei
and Kosrae States and the Marshall Islands, will keep spotty to low-
end showers possible through the next couple of days.

$$

Schank