Synoptic discussion for American Samoa.

469
FXZS60 NSTU 210113
AFDPPG

Area Forecast Discussion
National Weather Service Pago Pago AS
213 PM SST Fri Dec 20 2024

.Short term...

Current satellite imagery shows convection in the area surrounding
the Samoan islands, especially to the southwest. This convective
activity should bring numerous to widespread showers to the
islands during the evening and overnight hours. RAOB upper-air
observations from this afternoon depict an unstable environment,
that is moist throughout the profile. The moist environment is
expected to remain throughout the weekend. However, surface high
pressure to the north of the islands will help to stabilize the
atmosphere and limit convective coverage throughout the weekend to
scattered in nature despite the favorable moisture for convective
activity.

.Long term...

Another trough will move over the islands Monday. This will once
again enhance convective activity over this islands to numerous or
widespread through atleast Wednesday. Winds will shift out of the
north as the trough passes over the islands.

&&

.Marine...

Wave observations from Anu`u have recorded seas of 6 to 8 feet
throughout the day, steadily decreasing to 5 to 7 feet leading to
cancellation of the small craft advisory. Visual observations by
forecasters Barton and Manala recorded seas of around 4 to 6 feet
on the south coast of Tutuila, supporting the decreasing trend in
wave heights. Seas are expected to remain around 5 to 7 feet
through the weekend, evidenced by support from both the
decreasing heights throughout the day in observations and model
agreement in the decreasing trend. Winds will remain out of the
east to northeast at up to 10 knots, before they shift out of the
north with the arrival of the trough on Monday.

&&

.PPG WATCHES/WARNINGS/ADVISORIES...

A small craft advisory is cancelled

&&

$$

Barton/Manala

American Samoa's Tropical Cyclone Outlook 2024-2025

Synoptic discussion for American Samoa.