436
FXPQ50 PGUM 150754
AFDGUM

Area Forecast Discussion
National Weather Service Tiyan GU
554 PM ChST Sat Nov 15 2025

.Marianas Synopsis...
Partly cloudy skies with isolated showers and moderate to fresh trade
winds prevail across the Marianas. Buoys show seas between 5 and 6
feet while altimetry shows seas between 5 and 7 feet east of the
islands.

&&

.Discussion...
A dry trade-wind pattern remains anchored across the Marianas this
afternoon with only partly cloudy skies and isolated showers expected
through the middle of next week. An upper-level ridge is providing
sufficient subsidence over the region to suppress showers and keep
thunderstorms out of the forecast. By the end of next week and into
next weekend, this pattern is expected to change. A band of trade-
wind convergence, due to a trade surge, along with weak trade-wind
troughs are expected to move through the area. Latest guidance shows
these features more over Guam and Rota, but decided to keep in the
forecast for all of the Marianas for now, as things could change a
lot over the next few days.

&&

.Marine...
Not much changed expected for the marine forecast through the next
couple of days. Moderate to fresh trade winds with occasional strong
gusts look to continue through most of next week. Combined seas of 5
to 7 feet look to continue through Monday night. Around Tuesday, seas
look to gradually build, reaching 7 to 9 feet around Thursday. Seas
and wind could continue to increase Friday into the weekend as a
building high pressure system moves through to the north, resulting
in building trade swell and increased winds. Also, a low pressure
center moving east off of Japan could push a small north swell into
the region. Small Craft Advisory level seas and wind are possible
late next week into next weekend.

&&

.Eastern Micronesia...
An Intertropical Convergence Zone (ITCZ) now extends fully across
the region from 8N180 and stretches west-southwestward over Majuro,
north of Kosrae, and through Pohnpei. A few trade-wind troughs within
the ITCZ are helping spread showers across much of central RMI and
Kosrae State, soon to build across Pohnpei as well. Scatterometry
data also indicates a wind speed gradient with this feature, with
stronger trades of 15-20 kt and pockets of 20-25 kt winds north of
the ITCZ axis. Continue to expect gusts to 25 kt at times with
heavier showers tonight. Then, the ITCZ starts to fragment across
Pohnpei and Kosrae on Sunday. Meanwhile, a fairly unsettled pattern
looks to remain for Majuro into next week. Latest model guidance is
less supportive of a cutoff upper-level low to help support showers
over the next few days, although a fragmented ITCZ pattern is still
expected to bring periods of scattered showers and isolated
thunderstorms through the upcoming week.

Latest altimetry shows seas remain at 4 to 6 ft with seas increasing
to 5 to 7 feet near Majuro and 7 to 9 feet east of Majuro. This is
comprised of northeast trade swell and minor long-period north
swell. Wave models still indicate that seas will briefly subside 1 to
2 ft across the region this weekend, increasing again next week as a
trade-wind surge builds across the region. This is mainly north of
9N, however we will still monitor any potential for surf and small
craft hazards next week.

&&

.Western Micronesia...
Satellite observations show scattered showers across Chuuk and Palau,
and isolated showers across Yap. Altimetry data shows combined seas
between 4 and 6 feet across the region.

The main change with this forecast package was to bump PoPs up to 50%
across Weno tonight through Sunday night. Trade-wind convergence is
interacting with the Near Equatorial Trough (NET) to produce high-end
(50%) scattered showers. Shower coverage was generally decreased
across Palau the next few days with isolated to scattered showers and
isolated thunderstorms expected. This lull is due to the broad
circulation that was south of Palau now shifted well to the west-
southwest. Shower activity will increase towards the middle of the
week as the next broad circulation approaches. No changes were made
to Yap`s forecast. Isolated showers are expected through Sunday
night, and then influence from the NET and an embedded circulation
will allow for scattered showers to spread northwards towards Yap
Proper.

No changes were made to the marine forecast. Benign combined seas
of 4 to 6 feet look to continue through Tuesday night. By Wednesday,
seas are expected to rise 1 to 2 feet as a trade-wind swell moves
into the region. We are still monitoring the potential for hazardous
marine and/or coastal conditions for Weno and Yap Proper late this
week.

&&

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

$$

Marianas: Kleeschulte
East Micronesia: Cruz
West Micronesia: Williams