(CNN) — Flood alerts were in effect Saturday morning across parts of Southern California after a strong storm tore across the region, leaving at least two people dead, triggering blackouts and submerging cars on highways.
Flood warnings for San Bernardino and Riverside counties were to last until 7:15 a.m. PT (10:15 am ET), the National Weather Service said.
The rain is moving out of the area, providing a brief reprieve, CNN meteorologists said.
But another round is expected in the state, mainly affecting Northern California. It will begin overnight Saturday and should linger through Monday, with 2 to 4 inches of widespread rain expected, CNN meteorologist Allison Chinchar said. Some areas may see up to 10 inches.
The driving rain could dramatically reduce visibility, she warned.
The rain headed for Northern California could pose a threat to Oroville Dam, where rising water levels will test the limits of its damaged spillway.
Strongest storm this season
One of the most drenching storms to hit Southern California in recent years has already left a trail of destruction, including downed trees and power lines, sinkholes and roadways dotted with submerged cars.
One person was found dead Friday in a flooded vehicle in Victorville in San Bernardino County, firefighters said. A second storm victim, a 55-year-old man, was electrocuted when a power line fell Friday in the Sherman Oaks area of Los Angeles, the fire department said.
With heavy rain pounding the area, Duarte, northeast of Los Angeles, issued a mandatory evacuation order for 200 homes.
More than 131,000 customers lost power Friday night across the region, officials said.
The rain was so furious, a parking garage in Los Angeles turned into a waterfall.
Rainfall totals by the National Weather Service showed parts of Santa Barbara County have seen more than 7 inches of rain in two days. Parts of Ventura County have seen totals of more than 6 inches.
The storm has also blanketed higher elevations with snow.
Winter storm warnings were posted Saturday morning. National Weather Service said snow showers and gusting winds were expected.
Oroville Dam ‘is holding up’
Officials near Oroville Dam are watching the incoming weather after evacuations were ordered earlier this week when a swollen Lake Oroville and a damaged spillway at the dam led to a flash-flood threat.
The new round of rainfall brings more worries for communities south of the dam.
On Tuesday, officials downgraded the evacuation order to a warning, allowing 188,000 evacuees from Butte, Sutter and Yuba counties to return home.
On Friday, officials voiced optimism that the dam and lake could handle the upcoming rain.
“We have generated a large volume of storage space so we can take on a very big storm,” said Bill Croyle, acting director of the California Department of Water Resources
The threat level has been reduced for residents living near the dam, but Butte County officials advised those returning to their homes to “remain vigilant and prepared.”
“The dam is holding up, it’s structurally sound,” said Jay Smith, a spokesman for the California Department of Forestry and Fire Protection.