A powerful storm carrying a strong atmospheric river laid siege to California Wednesday, with evacuations issued because of the risk of life-threatening flooding and debris flows. The National Weather Service is warning of more flooding rains and strong winds in Northern and Southern California on Christmas Day.

Torrential rains unleashed widespread flash flooding and mud flows across Southern California on Wednesday, as authorities warned motorists to stay off roads while urging residents in flood zones to evacuate or shelter in place.

The National Weather Service (NWS) issued "life-threatening" flash flood warnings for parts of Southern California. Newsweek's live blog is closed.

A strong atmospheric river is moving across Southern California, bring heavy rain and threatening mudslides in recent burn scar areas.