A series of powerful atmospheric river events struck western Washington in early December 2025, bringing over 10 inches of rainfall in some areas, leading to catastrophic flooding, landslides and widespread infrastructure damage. Whatcom, Skagit, Snohomish and King counties, where major rivers like the Skagit, Green and White overflowed, were hardest-hit, triggering extensive evacuations. The widespread flooding, compounded by saturated soils and unusually warm Pacific moisture that further intensified the impacts of the storm series, led to a state of emergency and 24-hour operations by the U.S. Army Corps of Engineers (USACE), Seattle District.