A car crosses a flooded parking lot in Oroville, California, on Monday, October 25.
Noah Berger/AP

In pictures: West Coast faces a barrage of weather hazards

Updated 5:51 PM ET, Mon October 25, 2021

A car crosses a flooded parking lot in Oroville, California, on Monday, October 25.
Noah Berger/AP

A "bomb cyclone" with hurricane-like strength and a chart-topping "atmospheric river" coincided Sunday and continued into Monday, unleashing flooding rains, wet snow, strong winds and coastal surf across the western United States.

A bomb cyclone is a rapidly strengthening storm that increases 24 millibars (a unit of pressure) in 24 hours. Atmospheric rivers are narrow bands of concentrated moisture that cruise more than 2 miles above the ocean and release rain or snow when they hit land.

Santa Barbara County officials upgraded a recent evacuation warning to an evacuation order for parts of the Alisal Fire burn area. Concerns were mounting about dangerous debris flows developing as heavy rain was forecast to fall over the recently scorched earth.