494
FXZS60 NSTU 270053
AFDPPG

Area Forecast Discussion
National Weather Service Pago Pago  AS
153 PM SST Wed Jun 26 2024

.Short term...

The ridge of high pressure, giving American Samoa much drier than
average conditions for the past week, is starting to weaken. Data
from the balloon launched overnight and at noon showed a
significant inversion about 3,000 feet above the surface. This
make it very difficult for clouds to develop, let alone rain
showers. However, this inversion is forcast to weaken this
afternoon as the ridge retreats southward and a weak trough
approaches the territory. Clouds increase tonight along with the
risk of showers (from 20% today to 40% tonight). Dewpoint
temperatures are expected to rise, which will bring the humid
conditions back to around normal. The weather pattern is forecast
to remain the same through early Friday morning.

The aforementioned trough will retreat to the south overnight
Thursday and drier air is expected on Friday morning before a weak
trough from the northeast moves in. Therefore, isolated showers
are forecast in the morning before becoming scattered in the
afternoon.

.Long term...

The weather pattern is projected to return to normal for the
weekend and into early next week as a strong ridge moves back over
the region. The upcoming weather pattern doesn`t look it will be
as dry as the current ridge over the region. If showers occur,
however, it would be in the passing form. Easterly tradewinds may
reach up to 25 mph at times. Severe weather is not expected during
this time.

&&

.Marine...

As the easterlies decreased to a moderate breeze this morning and
early afternoon, seas eased to around 7 to 8 feet. A weak trough
moves closer to the region, however, winds are likely to increase
back to a fresh easterly breeze (16 to 21 knots) by Thursday and
is expected to remain through the weekend. Seas are forecast to
build on Thursday back to 7 to 9 feet and to reach 8 to 10 feet
for Friday through Sunday. The short period wind driven waves
will interact with a south/southeasterly swell, which will keep
the coastal waters choppy. Even though surf heights are forecast
to decrease tonight but longer period timing on Friday and
Saturday may increase surf to reach up to around 12 feet.

&&

.PPG WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

LaPlante