488
FXPQ50 PGUM 140553
AFDGUM

Area Forecast Discussion
National Weather Service Tiyan GU
353 PM ChST Sat Jun 14 2025

.Marianas Synopsis...
Partly cloudy skies with spotty showers and gentle trade winds
prevail across the Marianas this afternoon. Buoys show seas between
3 and 4 feet.

&&

.Discussion...
A dry trade-wind pattern is now in place across the Marianas and look
to continue for the next several days. Latest model guidance shows
little rainfall through the end of next week, with the GFS showing
around 1 inch for the Marianas, while the ECMWF shows less than on-
half inch. Basically, it looks to remain fairly dry through the
coming week.

&&

.Marine...
Benign marine conditions are expected through the week. Mostly gentle
winds will continue through at least the middle of next week.
Combined seas of 2 to 4 feet will slowly subside to 2 to 3 feet
Monday, then begin to build again around the middle of next week.
Surf is expected to fall sufficiently to allow the rip current risk
to become low along east facing reefs Sunday night.

&&

.Eastern Micronesia...
Satellite observations show isolated to scattered showers across
eastern Micronesia this afternoon.

A relatively quiet pattern is seen across eastern Micronesia today
with generally isolated to low-end scattered showers seen across
Pohnpei, Kosrae, and Majuro. The generally quiet pattern looks to
continue in the short term except for Kosrae. Currently, scattered to
numerous showers and isolated thunderstorms are ongoing east-
southeast of Kosrae. The surface trough associated with these showers
is expected to amplify as it moves westward. The GFS and ECMWF
disagree on the timing of this amplification with the GFS impacting
Kosrae with the heaviest showers before noon Sunday, while the ECMWF
brings in the heaviest showers in the afternoon period. For now, kept
Sunday a flat 50% chance for showers to meet in the middle, timing
wise.

As we move into next week, the models still hint towards enhanced
trade convergence across eastern Micronesia. The latest GFS run
develops a full blown ITCZ across the region as well. This would
increase shower and thunderstorm activity across the region. For
now, it looks like Kosrae will be in line for the heaviest showers,
so their forecast reflects the increased chances for showers. Trends
will need to be monitored to see how far north the trade convergence
or potential ITCZ sets up.

No changes were made to the Marine forecast. Combined seas are
between 4 and 6 feet across Pohnpei and Kosrae, and 5 to 7 feet
across Majuro. Combined seas could approach 8 feet for Majuro early
next week as the trade swell briefly increases.

&&

.Western Micronesia...
A disorganized but generally unsettled pattern continues across far
western Micronesia. A trade-wind trough extends south across Yap
Proper, and intersects a broad east-west oriented trough which
extends through the southern Republic of Palau, just to the south of
Sonsorol. There is a broad convergence boundary just north of this
trough, extending from east to west across Yap State and the ROP,
passing just north of Sonsorol and south of Koror. Scattered to
numerous showers and isolated showers are loosely organized about
these features, seen mainly to the east and south of Yap Proper near
Sorol and Eauripik, to the north of Koror, and to the south of
Sonsorol over the outer Indonesian islands. Here, scatterometry
reveals a moderate to fresh south-southwest flow with an embedded
area of strong winds just west of Pulau Bras. This monsoon-like flow
looks to stay south and west of Koror in the near term, but it may
drive a southwest swell into the area early next week, discussed
below. Disorganized low-level convergence and troughing will
continue to focus showers and thunderstorms near Palau and Yap over
the next few days with a quieter lull expected early next week.

To the east, satellite reveals dry conditions over and just upstream
of Chuuk Lagoon. Chuuk can expect increasing showers late tonight as
a convergence boundary develops south of Weno, maintaining low-end
scattered showers through the weekend. On Monday, a robust trade-
wind disturbance looks to develop just south of the area leading to a
more significant increase in showers, followed by a return to
quieter weather through the middle of next week.

Combined seas of 3 to 5 feet over Yap and Palau waters will come down
a foot or so through early next week as wind waves and trade swell
relax, coming back up by mid-week as a pulse of stronger trade swell
moves in. Palau may experience a southwest swell of around 2 feet
from Monday through Tuesday night, driven by monsoon-like flow
further south. Yap may see just the edge of this swell later around
Tuesday, so a 2-foot south swell has been included there. Chuuk can
expect combined seas of 3 to 5 feet this weekend through much of the
coming week, with gentle to moderate trades in store.

&&

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

$$

Marianas: Kleeschulte
East Micronesia: Williams
West Micronesia: DeCou