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AGUS74 KWCO 051958
HMDNWC

National Hydrologic Discussion - EXPERIMENTAL
NWS National Water Center - Tuscaloosa AL
200 PM CST FRI DEC 5 2025

Considerable flooding across portions of the Pacific Northwest beginning
late Monday and may linger through the week...

.Pacific Northwest...
A series of frontal systems will bring periods of heavy rainfall through at
least the middle of next week across western WA and OR with considerable
river flooding and urban flooding becoming increasingly likely. The
flooding impacts will be greatest on Monday evening through Wednesday of
next week when the heaviest rainfall (daily totals of 2 - 4") are expected.
Soils are wet following waves of precipitation over the past several weeks,
and daily rainfall through next week will sufficiently prime the hydrologic
environment. Minor to isolated major river flooding is forecast with peaks
beginning to occur late Monday evening, particularly in the foothills of
the Cascades and may continue through late next week. Fortunately, snow
levels are expected to remain in the higher elevations limiting the overall
snowmelt runoff component. Regardless, the magnitude and extent of
streamflow and river responses has increased which has increased our
confidence in Considerable flooding impacts. Model guidance has suggested
some southward expansion in the precipitation pattern so this area will
need to be closely monitored as the situation evolves over the weekend.

//JAC

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www.weather.gov/owp/operations

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