Areas of Excessive Rainfall and Severe Thunderstorms; Fire Weather Concerns in the Northern Plains and Four Corners Region

Widespread showers and thunderstorms may bring areas of flash flooding across much of the Southern Plains into the Gulf Coast region and the upper Ohio River Valley into the Mid-Atlantic. A large Pacific storm will bring widespread rain, gusty winds, and mountain snow to California and the Great Basin. Fire weather concerns expected in the Northern Plains and the Four Corners region. Read More >

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FXZS60 NSTU 270024
AFDPPG

Area Forecast Discussion
National Weather Service Pago Pago AS
124 PM SST Tue May 26 2026

.DISCUSSION...
A low pressure system to the southeast continues to migrate
further east as it pulls the trough line away from area. However,
unstable conditions remain over the territory as the trough
continues to produce widespread showers with possible
thunderstorms. Also favorable in producing heavy showers and gusty
winds from time to time are the single cell convections embedded
within the trough line. Winds will remain light and variable for
the short term forecast period, except during heavy showers and
nearby thunderstorms. These conditions are further supported by
the latest satellite imageries and upper air observations (RAOB)
from this afternoon (27/00Z). A moist atmosphere with thunderstorm
signals and strong upper level winds conducive of severe weather
patterns. Therefore, the threat of flash flooding and landslides
is possible as grounds have been saturated through at least
midweek.

Model data projects improving conditions starting late Wednesday
through the rest of the forecast period. As the aforementioned
trough moves out of the area, a high pressure system to the south
will generate moderate east-southeasterlies with embedded showers
on Friday night through the end of the long term period. No
imminent threat is expected for the rest of the forecast period.

&&

.Marine...
Rough seas continue to linger over the American Samoa coastal
waters for the last 12 to 24 hours. Data from the PacIOOS buoy
data near Aunu`u show wave heights remaining in the advisory
thresholds. However, model data shows a downward trend starting
tonight and remaining through at least Friday. By Friday night,
models are showing another large south swell with long periods
peaking at 15 seconds reaching the south facing shorelines and
remaining through the end of the forecast period (5 days out).
The long periods will likely enhance strong rip currents and
higher surfs. Thunderstorms embedded within the aforementioned
trough will produce gusty winds from time to time, and elevate
seas nearby. Otherwise, light and variable winds are projected
to remain over the area tonight through at least Friday morning.
These winds will increase to gentle and moderate easterlies by
Friday night through the end of the period. The threat of high
surfs and strong rip currents remain over the area.

&&

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

&&

$$

JTAllen