646
FXZS60 NSTU 140055
AFDPPG

Area Forecast Discussion
National Weather Service Pago Pago  AS
155 PM SST Thu Nov 13 2025

.Discussion...
Fair weather conditions have been observed throughout the day,
and are expected to hold over the territory through the remainder
of the week with passing showers and easterly winds of around 5
to 15 mph through early Saturday. An area of high pressure is
observed to the south of the territory with generally lower
pressure to the north and west. These high and low pressure areas
will be critical in the long term forecast.

The high pressure to the south will slowly drift northward and
closer to the territory into the weekend. Additionally, the
pressure to the north and west of the territory will further
decrease. This strengthening gradient between between low and
high pressure will intensify surface convergence near the
territory, forming a powerful surface trough by late Saturday or
Sunday. This surface trough will bring potential for
thunderstorms, heavy rainfall, flash flooding, and strong wind
gusts near showers and thunderstorms. Winds will turn out of the
northeast as the convergence strengthens.

There remains some uncertainty regarding the exact positioning of
the trough next week. Most model and ensemble data indicates that
the trough will linger in the area throughout the week. However,
there are outlier solutions, such as the GFS which has low
pressure systems embedded in the convergence pulling the trough to
the south of the area. Due to this uncertainty, we have the
highest confidence in the potential for thunderstorms and flash
flooding Sunday through Monday at this time. Beyond this weekend,
any deviations in the positioning of the trough could have a
large impact on the precipitation and wind outcomes.

No tropical development is expected within 300 nm from American
Samoa over the next 7 days.

&&

.Marine...
Ocean conditions for the rest of this week remain favorable as
seas are well below advisory levels, observed around 4 feet at
the Poloa and Aunu`u buoys. Winds are expected to remain at a
gentle breeze throughout the remainder of this week. A long period
swell from the northwest is expected to reach shores tonight. Long
periods generally enhance surfs and generate strong rip currents,
but should still remain below High Surf Advisory levels in this
case due to the low combinded wave height. By Sunday, a fresh
easterly breeze will develop just south and east of the territory
as the aforementioned convergence / trough forms. While not
expected to move directly over the territory at this time, the
fresh breeze will still be close enough to bring a short period
swell over the territory, increasing seas to rough conditions
Sunday into the new week. Additionally, gusts associated with
heavy showers and thunderstomrs may lead to enhanced and
unpredictable seas at times.

&&

.PPG WATCHES/WARNINGS/ADVISORIES...
NONE

&&

$$

Barton