A powerful storm, identified as a “bomb cyclone,” struck Northern California and other parts of the West Coast on the night of November 20, 2024, bringing intense rainfall, heavy snowfall, and damaging winds. The National Weather Service extended flood warnings into Saturday for regions north of San Francisco as the atmospheric river intensified. Santa Rosa received approximately 5 inches (13 cm) of rain in 24 hours, while certain areas recorded totals of up to 16 inches (41 cm). The Sierra Nevada faced a winter storm watch, with forecasts of 15 inches (38 cm) of snow above elevations of 3,500 feet (1,066 meters) and wind gusts exceeding 75 mph (121 kph). Washington’s Cascade Mountains recorded over a foot of snow, contributing to blizzard conditions. The storm triggered flash flooding, rockslides, and road closures, disrupting transportation and endangering communities across the region.

The storm caused severe damage, including widespread power outages, hazardous travel conditions, and fatalities. In Washington, nearly 376,000 power outages were reported, with fallen trees leading to two deaths in Lynnwood and Bellevue. California experienced approximately 21,000 outages, and Interstate 5 near the Oregon border was closed due to treacherous conditions. Additionally, flight disruptions at San Francisco International Airport and ferry suspensions in Washington underscored the storm’s impact on infrastructure. Officials emphasized the risk of further flooding, landslides, and road closures as rainfall persisted. The storm highlighted the vulnerability of regional infrastructure to extreme weather events and underscored the need for resilient planning to mitigate such catastrophic impacts in the future.