990
FXZS60 NSTU 260103
AFDPPG

Area Forecast Discussion
National Weather Service Pago Pago  AS
203 PM SST Sat May 25 2024

.DISCUSSION...
The latest satellite imageries shows a trough to the south of the
area, oriented northwest to southeast, crossing over the Fiji
Islands. This trough is expected to remain stationary as a ridge
to the north and east holds it in place through at least midweek.
The upper air data from this afternoon (26/00Z) shows instability
lingering in the area with the potential thunderstorms embedded.
Model data is showing a high pressure system to the southeast
continuing to transport a gentle to moderate easterly flow with
embedded showers over the territory for tonight through Wednesday
night. A much broader and stronger high pressure system to the
southwest will migrate eastward as it pushes a boundary layer
closer to the territory. Easterlies will turn southeast and
become fresh breeze by Thursday. These trade winds are expected to
gradually increase and possibly reach wind advisory criteria by
the end of the long term forecast period. With the trade winds
increasing, an increased potential for numerous showers is also
expected for this time frame.

Therefore, expect isolated to scattered showers with a gentle to
moderate east breeze for tonight through at least midweek. Winds
will turn southeast at moderate breeze with scattered to numerous
showers with embedded thunderstorms on Thursday through the end
of the new week.

&&

.Marine...
Calm and smooth seas remains across the American Samoa coastal
waters. Model data show these favorable conditions remaining
through at least Monday night, with seas in the 4 to 6 feet range
tonight through Monday, gradually building to advisory thresholds
by Monday night. Model data has been consistent in also showing a
large south swell reaching shores by Tuesday. This south swell is
expected to peak at 15 feet with the possibility of reaching the
lower end of the high surf warning criteria (>15 feet) by this
time frame. This is due to the aforementioned broad high pressure
system to the south-southwest, generating a far fetch wave series
from the south. Wave periods that are 15 or more seconds long is
indicative of enhanced surfs and strong rip currents. Winds will
remain at a gentle easterly breeze for tonight through at least
midweek, then increase to fresh breeze by the end of the forecast
period. Will continue to monitor the latest model runs for the
latest information.

&&

.PPG WATCHES/WARNINGS/ADVISORIES...
NONE

&&

$$

JTAllen