429
FXPQ50 PGUM 300850
AFDGUM

Area Forecast Discussion
National Weather Service Tiyan GU
650 PM ChST Sat Aug 30 2025

.Marianas Synopsis...
Gentle to moderate southerlies prevail across the region. Satellite
imagery and Doppler radar indicate southerly convective surges
entering the eastern waters. The buoys show seas are around 5 feet.

&&

.Discussion...
Little change is expected in the general weather trends over the next
several days. A broad trough extending from a tropical disturbance
northwest of Palau known as Invest 95W, will continue to pummel the
Marianas overnight with numerous heavy showers and some thunderstorms.
Some of these showers may carry near-gale gusts, especially near
outflow boundaries. Conditions will improve considerably beginning
Sunday, to become mostly dry briefly on Sunday night. Showers may
increase slightly on Labor Day, but thunderstorms are not expected to
return until Monday night, with on-and-off showers and some
thunderstorms expected for much of next week as a seasonally wetter
pattern returns.

&&

.Marine...
Combined seas of 5 to 7 feet are expected to taper down a foot over
the weekend, to then diminish another 2 feet by the middle of next
week as trade swell and wind waves diminish. A moderate risk of rip
currents is expected along east facing reefs for at least the next
several days. As trade swell and wind waves decrease, surf will
diminish further along all reefs, allowing rip current risk to
potentially become low along east facing reefs toward next weekend.

&&

.Tropical Systems...
The Joint Typhoon Warning Center (JTWC) has closed Invest 94W, that
focused on a broad area across Chuuk State, due to the lack of any
discernible circulation over the past 24 hours. Invest 95W is a weak
and broad circulation, currently located near 11N131E, northwest of
Palau, and embedded withing the monsoon trough that enters the region
from 11N130E and extends east-northeast up towards the Marianas,
passing to the north of both Palau and Yap. This is generating gusty,
locally heavy showers and moderate to fresh (15-20 kt) southwest
winds across Palau and Yap State. Across the Marianas, gentle to
moderate southerlies winds prevail, with scattered to numerous
showers, some locally heavy, which may generate some strong gusts
tonight. Invest 95W and the monsoon trough are expected to shift
north-northwest over the next few days, allowing the potential of
locally heavy showers and gusty across Palau, Yap and the Marianas to
decrease through Sunday and into the upcoming week. The potential
for Invest 95W to develop into a significant tropical cyclone over
the next 24 hours remain very low due to its disorganized nature.

&&

.Eastern Micronesia...
A broad trough at the leading edge of the Intertropical Convergence
Zone (ITCZ) is found northeast of Majuro and is generating a large
area of widespread cloudiness and scattered to numerous showers.
Farther west, a couple of trade-wind troughs are moving through
Pohnpei and Kosrae bringing scattered showers and a few thunderstorms
as well. The ITCZ pattern is not expected to extend much further
into the region, however, a trade-wind trough does look to break away
and move through the Marshalls over the next day or so. As these
features propagate westward, scattered showers are expected through
at least Sunday for Pohnpei and Majuro, and through tonight for
Kosrae. Afterwards, a drier pattern is expected through Tuesday,
before an ITCZ fragment stretches into the region, bringing another
round of scattered showers starting around Wednesday for Majuro and
Kosrae.

Altimetry and buoy data show seas of around 4 to 6 feet across the
region. Combined seas are expected to remain around this range over
the next few days, then may increase an additional foot in the latter
half of next week from minor northerly swell and a slight increase
in east-southeasterly swell. Light to gentle winds are expected to
increase to light to moderate next week as well.

&&

.Western Micronesia...
Latest satellite imagery shows numerous locally heavy showers and
isolated thunderstorms across and just north of Palau and Yap this
evening. These showers are mainly southeast of the broad circulation
being monitored as Invest 95W by JTWC, northwest of Palau near
11N131E and is discussed in more detain in the Tropical Systems
section above. Chuuk is experiencing scattered showers and isolated
thunderstorms as passing trade-wind troughs move through the State.
Palau and Yap are expected to another round of numerous locally
heavy rainfall and gusty winds around 30 kt tonight, with conditions
expected to gradually improve Sunday and into the upcoming week as
the monsoon pattern lifts northward, pulling the stronger southwest
flow and heavy showers with it. Seas and surf are expected to be
elevated and choppy, driven by gusty winds, and peaking at around 7
or 8 feet, remaining below the hazardous levels of 10 feet and 9
feet, respectively. Model guidance continues to support a weak ridge
of high pressure building into the region briefly around Tuesday,
which would also lead to a reduction in the intensity and coverage of
showers, before additional troughs move through the region.

For Chuuk, additional surface troughs moving through eastern
Micronesia will continue to produce periods of scattered showers and
isolated thunderstorms through Sunday. Models have started to suggest
the weak ridge of high pressure expected to develop between Chuuk
and the Marianas will shift westward slightly faster than expected,
which would shorten the length of drier weather, though winds are
still expected to be on the lighter side. Additional troughs are
expected to move into the region by the middle of the week, bring
additional periods of scattered showers and isolated thunderstorms.
Seas at Chuuk will be around 4 to 5 feet, driven by the primary
easterly swell. Seas are expected to decrease 1 to 2 feet over the
next few days as the east swell subsides slightly.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...None.
MP...None.
Marianas Waters...None.
&&

$$

Marianas: Montvila
East Micronesia: Cruz
West Micronesia: Schank