454
FXZS60 NSTU 160100
AFDPPG

Area Forecast Discussion
National Weather Service Pago Pago AS
200 PM SST Mon Jun 15 2026

.Short term [tonight through Wednesday night]...
This afternoon`s 00Z RAOB upper-air observation revealed a
rapidly moistening environment as an active trough observed on
satellite to the north and west of American Samoa has moved
closer to the territory, with deep convection observed near and
over Western Samoa throughout the day. A low pressure center
denoted Subtropical Storm 96P (SS 96P) by the Joint Typhoon
Warning Center is currently located between Vanuatu and Fiji, and
moving to the southeast. SS 96P will pass to the south of
American Samoa tonight through midweek as it progresses
southeastward. SS96P should pull the aforementioned trough
southeastward and over the American Samoa islands by this evening
through midweek. GFS and ECMWF model data indicates very high
atmospheric moisture content and an extremely favorable parameter
space over American Samoa for flash flooding and embedded
thunderstorm activity tonight into Tuesday. Given the high
confidence in flash flooding potential, a Flood Watch is now in
effect through at least Tuesday night.

Winds have slightly decreased today, remaining breezy but now
falling below Wind Advisory levels. Wind speeds should continue to
steadily decrease throughout the short term period as SS96P`s
passage to the south turns them out of the north to northeast by
midweek. Lingering showers are expected to remain on Wednesday,
but the flash flooding threat should decrease after Tuesday
night.

.Long term [Thursday through Monday]...
As SS 96P moves out of the region to the southeast, a more stable
weather pattern will take over across American Samoa by late week.
Light and variable winds are expected Thursday before breezy
southeasterly trade winds take over Friday into the weekend due to
a ridge of high pressure developing over New Zealand. Embedded
passing trade wind showers are likely to be embedded in the breezy
southeasterly flow, but overall rainfall should be near to below
average during the long-term forecast period.

&&

.Marine...
With a slight decrease in wind speeds today, wave heights have
subsided from around 15 feet early this morning to around 13 feet
by afternoon at Aunu`u buoy. Given this subsiding trend that is
expected to continue, the High Surf Warning has now been
downgraded to a High Surf Advisory. While conditions are slowly
improving, seas still remain dangerous tonight at over 10 feet,
making marine navigation difficult to impossible, especially for
inexperienced mariners and small vessels. Large surf and powerful
rip currents remain potentially deadly hazards despite no longer
being at warning levels. Additionally, heavy showers and
thunderstorms may further elevate seas and surf at times.

Winds continue to gradually weaken to a gentle to moderate breeze
by midweek as they turn out of the north to northeast. Textured
choppy seas likely to persist until Thursday, when seas finally
subside below advisory levels as winds become light and variable.
These favorable marine conditions will likely be short-lived as
fresh southeasterly trades are forecast to build seas back to
choppy conditions Friday into the weekend.

&&

.PPG WATCHES/WARNINGS/ADVISORIES...
High Surf Warning downgraded to High Surf Advisory.
Wind Advisory is Cancelled.
Flood Watch is now in effect.
Small Craft Advisory remains in effect.

&&

$$

Barton