Heat Persists in the Southwest; Elevated to Critical Fire Weather in the Great Basin; Poor Air Quality in the West

Dangerous heat will persist across the Southwest U.S. through this week, easing by next week. The heat will focus further east in the Great Plains and Mississippi Valley beginning next week. Elevated to locally critical fire weather conditions will persist for the Great Basin today. Poor air quality lingers for the Northwest, Great Basin, Central Rockies into the Plains. Read More >

623
FXZS60 NSTU 040102
AFDPPG

Area Forecast Discussion
National Weather Service Pago Pago AS
202 PM SST Mon Aug 3 2026

.Short term...

Satellite imagery shows a trough has began to move over American
Samoa from the southwest. Numerous to widespread showers are
likely throughout the rest of the day and overnight as this trough
is expected to be slow moving. Flash flooding is not anticipated
from this rain, but ponding on roadways may occur. Southerly
winds are forecast to increase overnight.

A high pressure system to the southwest is projected to strengthen
overnight and tomorrow. This ridge is forecast to interact with
the trough to elevate winds to around 15 mph. The trough is to
give mainly cloudy skies along with numerous to widespread showers.
By Wednesday, the trough will likely be pushed northward by the
ridge. As this occurs, showers become passing tradewind showers
and winds may reach up to 25 mph. Temperatures will be noticably
cooler throughout this timeframe.

.Long term...

By Thursday through the weekend, winds become more southeasterly
and continues to increase. Winds will likely be within Wind
Advisory conditions with winds up to around 35 mph with higher
gusts. Impacts from Wind Advisory level winds include: blowing
trash, tipped garbage cans, lawn furnature blown over, and an
increase of falling coconuts and fronds from coconut trees. This
will also likely produce passing tradewind showers with a mix of
sun and clouds. Temperatures will remain cooler than average.

&&

.Marine...

Data from the PacIOOS buoys to the east of Aunu`u and to the west
of Tutuila show sea conditions below Small Craft Advisory levels.
However, a changing weather pattern will slowly build seas
throughout the week. Southerly winds are to increase starting
tonight to moderate breeze, reaching to around 15 knots, through
Tuesday night. As a ridge of high pressure strengthens over the
coastal waters, winds are to increase to a strong southeasterly
breeze for Thursday through the weekend. Therefore, we expect seas
to build up to 10 feet for Tuesday and Wednesday then up to
around 15, potentially higher, for Thursday through the weekend.

Expect high surf conditions for late Tuesday and Wednesday,
especially along the southern coasts before becoming warning
levels on Thursday through the weekend. Small Craft Advisory
levels are likely starting Tuesday.

&&

.PPG WATCHES/WARNINGS/ADVISORIES...

NONE

&&

$$

LaPlante