Heavy to Excessive Rainfall This Week from the Southwest into Central U.S.

Pacific tropical moisture wrapping into a storm over the southwest U.S. will continue a multi-day heavy rainfall event this week that will extend into the Midwest and southern Plains. Considerable flash flooding is possible across portions of New Mexico and west Texas today through Wednesday. Read More >

533
FXZS60 NSTU 290057
AFDPPG

Area Forecast Discussion
National Weather Service Pago Pago AS
157 PM SST Mon Sep 28 2026

.DISCUSSION...
The latest satellite imageries together with the latest upper air
observations (RAOB) from this afternoon (29/00Z) show cloudy
conditions at the surface boundary layer (surface to 800 mb-SBL).
Moisture bound to the SBL continue to precipitate throughout the
day in brief showers around different parts of the islands. Above
the SBL, conditions are stable and thus, remain dry. In these
conditions, expect a low chance of flash flooding to occur as
winds are also strong enough to push away moisture in the area.
This weather pattern is expected to remain for the rest of the
week as another high pressure system from the southwest will
follow the current high pressure system moving east. The latter
high pressure system will likely continue to hold an active trough
to the north of the area through the end of the forecast period.

Thus, expect moderate to strong trade winds with higher gusts, and
embedded scattered to numerous showers for tonight through the
rest of the forecast period.

&&

.Marine...
The threat of hazardous seas, enhanced surfs with a high rip
current risk remains across the American Samoa coastal waters. The
moderate to strong trade winds over the area will continue to
generate wind waves and choppy conditions throughout the week.
Models suggest a downward trend starting tonight through at least
Wednesday. However, by Wednesday night, seas are expected to build
again as winds will also increase. By this time frame also, wave
periods will likely be more than 10 seconds long and will increase
the risk of strong rip currents and higher than normal surfs,
especially for the south to east facing shores of all islands.
These conditions will remain for the rest of the forecast period.

&&

.PPG WATCHES/WARNINGS/ADVISORIES...
High Surf Advisory
Small Craft Advisory

&&

$$

JTAllen