989
FXPQ50 PGUM 070812
AFDGUM

Area Forecast Discussion
National Weather Service Tiyan GU
612 PM ChST Sun Dec 7 2025

.Marianas Synopsis...
Gentle to moderate northeasterlies prevail across the region tonight.
Satellite imagery and Doppler radar indicate light passing showers in
Guam and Rota waters. Buoys show seas are about 5 to 6 feet.

&&

.Discussion...
A minor surface trough is expected to bring low-end scattered showers
to the Marianas near midnight tonight, followed by an extensive
period of drier weather for much of the forecast period. As shearline
fragments shift southward from elongated frontal systems to the
north, this will bring breezy conditions late this week.

&&

.Marine...
Significant northerly swells generated by distant synoptic systems
continue to produce hazardous surf and a high risk of rip currents
along north facing reefs of the Marianas through at least late
tonight. Surf is then likely to fall below hazardous levels
thereafter as this pulse in northerly swell diminishes, which will
also allow rip current risk to drop to moderate along said reefs.
Combined seas of 5 to 7 feet are expected to persist, as the
seasonal trade swell and secondary northeasterly swells linger.

&&

.Eastern Micronesia...
The main forecast challenge was in determining when to end
headlines. The Pohnpei buoy checked in with 9.91 feet and a recent
increase in both sea and swell heights. Majuro is also still seeing
the effects of the trade-wind surge to the north, with an added
concern of another peak in the King Tides later this evening/first
half of the night, before they start to subside. As such, left the
Coastal Flood Advisory going through tonight at Majuro, while
extending the Small Craft Advisory for Pohnpei and Majuro, which now
expires at 3 PM Monday (coinciding with the High Surf Advisory
expiration).

As for rainfall potential, Pohnpei looks to remain mostly dry with
just isolated showers through Thursday. Meanwhile, a remnant shear
line will keep scattered showers going at Kosrae through the next 12
hours, becoming isolated Monday.

Then, an approaching surface trough will increase showers by Tuesday
at Majuro and Tuesday night for Kosrae, with scattered showers going
at both locations through the end of the week. This feature could
also increase rainfall potential at Pohnpei by Friday.

&&

.Western Micronesia...
Satellite this afternoon continues to show a fairly dry regime across
much of western Micronesia. Scattered showers are building in across
Chuuk along the axis of a shallow trough which is propagating
westward through the area. Meanwhile, an area of scattered showers
and isolated thunderstorms is seen over and southwest of Sorol in Yap
State, while dry conditions persist for Yap Proper and Palau. This
area of showers is located along a weak embedded trough north of the
Near-Equatorial Trough (NET) axis, which has shifted further south of
the area over the last day. Strong easterly winds and divergence
aloft have been supporting thunderstorms in this area east to
southeast of Palau and Yap throughout the day, but models show this
upper-level support moving away west of the area tonight. The area of
surface troughing looks to shift gradually west-southwest and
increase showers near Palau and Yap Monday and Monday night, but
models keep most of the showers to the east and south of coastal
waters. Chuuk will see scattered showers tonight and Monday as the
surface trough moves through. Thereafter, a dry trade-wind pattern
looks to remain steady through the end of the week with mostly
isolated showers across the region.

Altimetry data shows 6 to 8 foot seas across much of the region near
and north of Yap and Palau, with 9 foot seas seen to the northeast
of Chuuk. A High Surf Advisory is in effect for north-facing reefs of
Chuuk through 5 PM ChST Monday as a pulse of elevated long-period
north swell moves through the region, combined with the elevated
trade swell. North swell is diminishing further west near Palau and
Yap, but will support hazardous surf up to 9 feet for north-facing
reefs of Yap through late tonight. For Palau, the High Surf Advisory
and Coastal Flood Statement expired this afternoon as high King tides
and north swell continue to diminish. Seas should decrease slightly
across the region toward the end of this week as background trade
swell and north swells relax. Winds will remain light to moderate for
Palau and Yap throughout the forecast period, with mostly moderate
trade winds expected for Chuuk through at least Tuesday before
diminishing in the latter half of the week.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...High Rip Current Risk until 4 AM ChST Monday for GUZ001.

     High Surf Advisory until 4 AM ChST Monday for GUZ001.

MP...High Rip Current Risk until 4 AM ChST Monday for MPZ001>003.

     High Surf Advisory until 4 AM ChST Monday for MPZ001>003.

Marianas Waters...None.
&&

$$

Marianas: Montvila
Eastern Micronesia: Doll
Western Micronesia: DeCou