Los Angeles Braces for Floods as Atmospheric River Nears

California will get more flooding rains starting late Saturday, unfolding into early next week, as another powerful atmospheric river rolls in off the Pacific Ocean.

Los Angeles will likely get 5 to 6 inches (12.7 to 15.24 cm) of rain, while Santa Barbara is set to get up to 8 inches and the mountains and hills along the coast may have 10 inches or more, said Marc Chenard, a senior branch forecaster with the US Weather Prediction Center. This comes on the heels of a system that already caused floods from San Francisco to Southern California.

“It does look like it will be a significant event and it will be a longer duration than this past one,” Chenard said by telephone. “The fact that it is later in the year, on top of what has been a wet period, surely makes everything worse.”

With streams and rivers already bursting and the ground saturated, the risk of floods throughout central and southern California are high. In addition, mudslides are likely and with high winds there is a growing chance of power outages. California has already had scenes of widespread flooding in San Diego last month and throughout the state this week. Los Angeles International Airport received 2.49 inches on Thursday.

The Los Angeles River near Wardlow Road, has risen about 2.7 feet (82.3 cm) since Thursday, the National Weather Service said. Looking forward, the Santa Clara River near the town of Piru will rise 2.27 feet by Monday. Both will still be well below flood stage. Meanwhile, in coastal areas of Orange County waves are forecast to reach 10 feet.

“Stream flow are well above average, the base conditions are well above average,” Chenard said. This means the danger for flooding has a head start.

In addition to the rain, heavy snow is forecast for the Sierra Nevada at 5,000 feet or higher through early next week. As much as 2 feet (61 cm) of snow may fall with rates of 1 to 2 inches per hour possible, the National Weather Service said.

A year ago a string of atmospheric rivers – long plumes of moisture off the Pacific – killed at least 22 people and caused $4.6 billion in losses and damage, according to the National Centers for Environmental Information.

(Adds details on river and surf numbers in the fifth paragraph.)