The West Coast is braced for an atmospheric river event that threatens flash flooding and power outages from heavy rain and snow, making travel conditions hazardous or even impossible for some commuters.

At least some debris flow is ongoing in the Malibu area, with portions of the Pacific Coast Highway closed. The same storm system driving severe weather elsewhere in the country is fueling one of the most widespread and potent rounds of rain in Southern California since the historic January fires.

Several areas in Southern California could have scattered showers throughout the day, but the potential for "damaging flooding" will not increase until the evening to overnight hours.