A slow-moving atmospheric river megastorm that first impacted the Bay Area, Sacramento Valley, and the Central Coast of California on Saturday worked its way down the state over the weekend, leaving a windy, wet path of destruction in its wake. According to the Los Angeles Times, the storm has caused two deaths thus far, along with flooding, mudslides and damage to power lines that have led to widespread outages.

Atmospheric rivers are long, narrow areas in the atmosphere that transport most of the water vapor outside of the tropics, according to the National Weather Service (NWS). When these rivers make landfall, they usually release this water vapor as rain or snow. The rivers that contain the most water vapor and strongest winds can cause massive amounts of destruction when they stall over watersheds that are already vulnerable to flooding.

The storm stalled over the Los Angeles metropolitan area on Sunday, creating what the NWS called "one of the most dramatic weather days in recent memory." As of Monday, the NWS reported the main band of steady rain had decreased in intensity, but that it remained straddling Los Angeles and Orange Counties.