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TWDPQ

Tropical Weather Discussion...CORRECTED
National Weather Service Tiyan GU
1228 PM ChST Sat Aug 30 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...
Two Invest areas are associated with the monsoon pattern across
western Micronesia. Invest 94W is located over northwestern Chuuk
State and is seen as a broad area of troughing, located near
8N147E. Current satellite imagery shows a compact area of
moderate convection within 200 miles of its location and latest
ASCAT analysis does not indicate a circulation at this time. 94W
is not favored to have significant development over the next day
or so, but will be monitored closely as it drifts northwest over
the coming days.

Invest 95W is a broad, weak circulation north of Palau with an
elongated center near 10N135E. Deep cloud cover and robust
convection exists mainly within its western and southwestern
sectors. The current potential for 95W to develop into a
significant tropical cyclone over the next 24 hours is very low.
However, latest model guidance suggests that 95W may be better
organized as 95W moves west-northwestward, likely exiting the
region over the next couple days.

...OTHER WEATHER SYSTEMS...

MONSOON TROUGH...
The monsoon trough enters the region near 12N130E extending east-
southeast to Invest 95W north of Palau, then to Invest 94W in
northwestern Chuuk State, and ending near 10N150E. Dense cloud
cover and deep convection is focused on the western to
southwestern sectors of 95W. Convection becomes more widespread
farther east and within 200 miles of the boundary. The overall
monsoon trough and pattern is shift northwestward, with moist
westerlies remaining focused towards the embedded circulation,
94W.

TRADE-WIND TROUGHS...
Several trade-wind troughs are moving north of the monsoon
pattern, generating scattered to numerous showers and a few
thunderstorms across the Marianas. One trough is west of the
Marianas, from 14N139E to 20N142E. Another trough extends across
Guam and the southern CNMI, from 12N141E to 17N151E. Another
trough extends across parts of the northern CNMI, from 17N146E to
25N151E. The last trough is east of Iwo To, from 22N144E to
25N144E. These troughs will propagate westward and possibly
merge due to a northwestward shift the monsoon pattern.

Farther east, a weak trade-wind trough is moving north of Wake,
one extends from 21N168E to 25N170E. This feature is interacting
with an upper-level trough to produce scattered showers and a few
thunderstorms. This feature is expected to propagate westward with
little change in intensity.

Across eastern Micronesia, a broad trade-wind trough extends
across much of Pohnpei State, from 1N157E to 13N159E. East of
Kosrae, a weaker trough extends from 3N165E to 8N167E. These
features are generating scattered showers and a few thunderstorms
within 150 miles of the boundaries. These trough is expected to
continue propagating westward over the next few days.

TUTT...
The Tropical Upper Tropospheric Trough (TUTT) curves from 25N180
to upper-level lows near 24N172E and 23N165E then continues
southwestward to near 11N150E. Another trough segment stretches
across the northern part of the region as well, from 25N140E to
an upper-low near 24N151E. These features are providing some
ventilation to surface features, generating scattered to numerous
showers and isolated thunderstorms southwest of Minamitorishima,
from 19N to 25N from 147E to 155E, and north of Wake Island, from
21N to 25N between 167E and 173E. The TUTT is expected to show
little change in either location or intensity through the weekend.

...ITCZ...
An Inter-Tropical Convergence Zone (ITCZ) is located northeast of
Majuro, roughly from 9N173E to 10N180. Low-level convergence
associated with the ITCZ is generating moderate convection between
5N and 12N, with deepening convection east of the Date Line. The
ITCZ is not expected to extend much further into the region,
although a trade-wind trough may break away and move through the
northern Marshalls over the next day or so.

$$

IC