199
FXZS60 NSTU 170124
AFDPPG

Area Forecast Discussion
National Weather Service Pago Pago  AS
224 PM SST Fri May 16 2025

.Short term...

Satellite imagery throughout the morning and early afternoon hours
show the ridge of high pressure remaining over the American Samoa
islands as a trough remains just to the north and east.
Thunderstorms have been detected just to the east of Rose Atoll
throughout this time. However, the trough is expected to weaken
as it slowly moves westward. We are going to increase the risk of
rainfall to numerous (60% chance) through Saturday night, but
flash flooding is not likely with this rainfall. Winds are a
little lower than expected today, but are still forecast to
increase to around 15 to 20 mph.

A weak low is projected to form well to the southeast of the
American Samoa islands on Sunday, but the trough is to extend
northwestward to the territory. In the meantime, a weak ridge to
the southwest is to keep the trough over the region. The risk of
showers will increase back to numerous on Sunday and Monday, but
the trough is expected to be weak. Flash flooding is not likely.
Southeasterly winds are kept around 15 to 20 mph.

Overall, the chance of rainfall is about average throughout the
year through the beginning of next week. Severe weather is not
expected.

.Long term...

Overall, there are also no signs of severe weather from mid to
late week next week. The east/southeasterly winds may reduce to
around 10 mph by midweek, but a strong ridge is projected to move
over the islands by late in the week to bring winds up to 20 mph
which is still below advisory levels.

&&

.Marine...

A moderate southeasterly breeze remained over the American Samoa
coastal waters. However, the breeze is forecast to slowly increase
throughout the afternoon to become a fresh breeze throughout the
overnight hours. This is forecast to create choppy conditions
throughout the coastal waters region and a Small Craft Advisory is
likely to remain through around Monday. Winds up to 20 knots may
be worst case scenario as the interaction between the ridge and a
trough near the islands may not be as strong as originally
anticipated. Long period swell from the southwest on Monday and
Tuesday will likely build surf to High Surf Advisory conditions.

&&

.PPG WATCHES/WARNINGS/ADVISORIES...

A Small Craft Advisory is in effect.

&&

$$

LaPlante