376
FXZS60 NSTU 220115
AFDPPG

Area Forecast Discussion
National Weather Service Pago Pago  AS
215 PM SST Tue Jul 21 2026

.Short term...

Partly cloudy skies were observed over the American Samoa islands
from mid-morning through the early afternoon hours. The latest
balloon data shows an inversion, a warming layer of the
atmosphere, around 3 to 4 thousand feet above ground. This
generally creates less clouds, let alone rainfall.

However, this inversion is to slowly dissipate through the
overnight hours. A ridge of high pressure is to remain over the
region, however, and is to keep showers isolated to scattered
through the overnight and Wednesday. Easterly winds of 10 to 15
mph tonight decrease of a light and variable wind during the day
Wednesday as the ridge weakens.

Currently, there is a trough seen via visible satellite imagery
over the Fiji region extending from a low pressure system to the
southeast. This trough is forecast to move westward and to move
over the American Samoa islands on Wednesday night through
Thursday night. This will bring more clouds than sun throughout
the day and numerous showers (60 to 70% chance) during this time.
Winds are to become southerly on Thursday up to 20 mph, but
decreasing to around 10 to 15 mph at night.

.Long term...

The trough is to move east by Friday. A ridge from the southwest
is forecast to continue generating southeasterly winds up to 15
mph. The risk of rain decreases. If showers occur, it will be in
the passing form. Otherwise, more clouds than sun are forecast
with temperatures to be slightly cooler than average. However,
not as cold as late last week and this past weekend.

&&

.Marine...

Seas continue to slowly ease as easterly winds become a gentle to
moderate breeze over the American Samoa coastal waters. However,
the PacIOOS buoys to the west of Tutuila and to the east of Aunu`u
still shows seas around 8 feet. This is primarily due to a
southerly swell currently moving through the region. This swell is
producing surf in the advisory level conditions (12 to 15 feet).
Even through surf is below warning status, swimming is still not
recommended for inexperienced swimmers and for experienced
swimmers to use caution along the southern and southern shores of
American Samoa.

For tomorrow, expect high surf to continue along the southern and
coasts. Surf is forecast to likely fall below advisory levels
later this week, but expect Small Craft Advisory conditions to
remain. Winds become a moderate to fresh southerly breeze on
Thursday then becoming a moderate southeasterly breeze for the
rest of the week and weekend.

&&

.PPG WATCHES/WARNINGS/ADVISORIES...

A High Surf Advisory remains in effect.
A Small Craft Advisory remains in effect.

&&

$$

LaPlante