999
FXZS60 NSTU 270033
AFDPPG

Area Forecast Discussion
National Weather Service Pago Pago AS
133 PM SST Fri Dec 26 2025

.Short term...

Satellite imagery throughout the morning and early afternoon hours
shows showers with isolated thunderstorms around the American
Samoa islands. A trough is shown extending from a low pressure
to the south of the Pitcairn Islands to American Samoa with wind
convergence from a high pressure system centered from the south of
Tonga and another high pressure system to the east/southeast of
French Polynesia.

Even though there is weak wind convergence over the American Samoa
islands, the latest balloon data from the launch midday today
shows a very moist atmosphere above the territory. Satellite
imagery also shows scattered cumulonimbus clouds that typically
produce heavy rain and potential thunderstorms. This weather
pattern is anticipated to remain over, or at least near, the
territory through at least Saturday night. If any convection
occurs over the islands, rainfall is likely be slow moving and may
be potentially heavy at times with an isolated thunderstorm.
Since there is a possibility of heavy rainfall throughout this
time along with poor stormwater drainage throughout much of the
territory, a Flood Watch has been issued for all islands of
American Samoa through Sunday. More clouds than sun are
anticipated for the rest of the day today and Saturday. Winds
remain light, but gusts may occur in areas of potential heavy
showers.

.Long term...

For next week, a low pressure system is anticipated to develop to
the east of Rose Atoll and move away from American Samoa. As this
occurs, drier air from the south is to move over the islands for
the majority of next week. This will lead to below average
rainfall, plenty of sunshine, and above average temperatures.
Winds are to remain light.

The aforementioned low, to develop to the east of Rose, will be in
an area of slightly favorable conditions for tropical
development. If tropical development occurs, adverse conditions
are expected to be well to the east of American Samoa. We will
continue to closely monitor this area.

&&

.Marine...

Conditions remain below Small Craft Advisory levels over the
American Samoa coastal waters. However, during rainfall this
morning the PacIOOS buoy to the east of Aunu`u showed building
seas during rainfall in the area. Throughout the rest of the day
today through at least Saturday, there is a possibility of heavy
rainfall that may bring gusts to cause localized enhanced seas.
Even though sustained winds and seas overall are projected to be
below the Small Craft Advisory levels, be aware of potential
thunderstorms and localized heavy rainfall.

Otherwise the trough is anticipated to move away from the American
Samoa coastal waters in the beginning of the week, winds are
forecast to be gentle with weak swell from the north. Therefore,
ideal sea conditions are forecast for the majority of the upcoming
week.

&&

.PPG WATCHES/WARNINGS/ADVISORIES...

A Flood Watch is in effect.

&&

$$

LaPlante