000
FXZS60 NSTU 050059
AFDPPG

Area Forecast Discussion
National Weather Service Pago Pago  AS
159 PM SST Thu Sep 4 2025

.DISCUSSION...
Precipitable Water (PWAT) content over the area shows moisture
lingering, and following in the east-southeast wind flow. This
moisture is shown on satellite as a boundary layer between the
strong high pressure system to the south and the troughing to the
north of the islands. Model data is showing the boundary layer
remaining over the area as the aforementioned high pressure system
migrates east through the rest of the week. Also, with the boundary
layer over the area, scattered to numerous showers, heavy at
times, with gusty winds is expected to remain for the short term
forecast period.

By Sunday, model solutions are showing the aforementioned high
pressure system exiting to the southeast, while a low pressure
system from the southwest migrates south of the area. With this
scenario in play, model data shows the low pressure system
migrating further east as it turns winds northeast to north to
light and variable from Sunday through at least Tuesday. As winds
turn while the low pressure moves east, a trough to the west,
connected to the low pressure is pulled closer to the islands,
increasing the potential for flash flooding conditions for this
time frame. Once the low pressure system exits to the south,
another high pressure system to the west will migrate east as it
pushes the trough further north and east of the territory. The
light and variable winds will again turn south to southeast at a
moderate to fresh breeze with mainly scattered showers for the
rest of the forecast period.

&&

.Marine...
Combined seas continue to stay rough over the last 24 hours. Wave
heights of 8 to 10 feet with intermittent peak periods less than
10 seconds are reported from the PacIOOS buoys. However, model
data show seas remaining at the same height levels but with
periods peaking at around 13 or more seconds by Friday morning. As
a function of the long periods, surfs will be much higher closer
to shores and rip currents will likely be stronger, especially
during tide tranisition times from high to low tides. These
conditions will likely remain for the rest of the forecast period,
as winds sustain at moderate to a fresh breeze. Additionally,
with a trough expected to move over and near the islands by late
Sunday, embedded thunderstorms has the potential to elevate seas
and winds nearby. Thus, the advisories for high surf and small
crafts remains in effect through at least Sunday. By Monday, seas
will start to ease off as winds are expected to decrease to light
and variable during this time frame. The threat of rough seas,
high surfs and a moderate rip current risk remains for this
forecast period.

&&

.PPG WATCHES/WARNINGS/ADVISORIES...
High Surf Advisory
Small Craft Advisory

&&

$$

JTAllen