Atmospheric river aimed at SoCal: Flooding alerts for millions, thanks to El Niño

The winter season’s first significant storm is set to wallop southern California over the next few days, bringing heavy rain and the threat of flooding to millions of people. In addition, forecasters warned that mudslides and power outages are also possible.

This will be the area’s first El-Niño influenced storm, one that’s fueled by an atmospheric river of moisture, the National Weather Service said. It’s expected to be the biggest rainstorm for the region since Hurricane Hilary dumped up to half a foot of rain in August, AccuWeather forecasters said.

In all, some 22 million people live where a flood watch is in effect, including most of the Los Angeles and San Diego metro areas.