The storm drenching Southern California is expected to drop as much as five inches of rain by late Friday, and forecasters are not ruling out more rain through Sunday.
Downtown Los Angeles received 2.35 inches of rain Wednesday, setting a record for the date. Water from overloaded drains swelled onto streets and freeways, a mudslide shut down part of a crucial north-south interstate, and large areas of the region remained under a flood watch. Police closed areas prone to flooding, fire stations offered sandbags to protect doorways, and utility crews worked to restore power to several thousand customers.
If motorists had relearned their wet-driving skills by the storm's second day, they were not showing it.
In the Los Angeles area alone, the California Highway Patrol had logged more than 600 collisions and other incidents by 5 p.m. Wednesday, about three times the number from a comparable -- but dry -- period last week.
In Pacoima, a driver died when his van rear-ended a Caltrans truck, but it was unclear whether the weather had contributed to the accident.
Orange and Ventura county traffic accidents increased too, the CHP said, but no serious collisions were reported.
Farther north, on the Golden State Freeway grade known as the Grapevine, a sliding hill trapped cars in as much as three feet of mud, rocks and brush.
CHP officers shut down the southbound lanes, while Caltrans worked into the evening to shore up the slide area.
"As quickly as Caltrans is grading it up, it's probably coming down twice as fast," CHP Sgt. Jack Skaggs said. "Right now we're fighting a losing battle."
As motorists cursed the weather that fouled their commutes, residents in rural canyons rejoiced. Slopes in the Santa Ana Mountains were sprouting wildflowers in yellow, blue and purple.
"We need it very badly," said Bruce Newell, who oversees the local firehouse in Orange County's Modjeska Canyon.
Off the roads, at a Fullerton manufacturing firm, two employees were injured when a section of the roof gave way under the weight of pooling water.
And in Ventura County, a sheriff's helicopter and a lifeguard rescued a homeless man who had been sleeping on a rapidly eroding sandbar at the mouth of the Ventura River in Ventura.
Late Wednesday, three people were pulled from the water near the Seal Beach Pier in an apparently storm-related incident, officials said. Two were taken to a hospital, one in full cardiac arrest, they said.
This storm ended six weeks of spring-like weather and followed the driest January on record in Southern California.
The storm brought the rainfall total since July 1 at the USC weather station to 8.99 inches, just above the average of 8.68 inches, the National Weather Service said. The old rainfall record for the date was 2.3 inches, set in 2001.
With temperatures in the 50s, snow was predicted only at elevations higher than 7,500 feet. "Warm storms are the ones that carry a lot of moisture," Weather Service meteorologist Bruce Rockwell said.
Ski and snowboarding slopes in the San Bernardino Mountains were closed Wednesday "due to lack of interest." There was no snow falling -- just rain -- and it was too warm and humid to make any flakes.
"With the [low] volume of business that we'd be doing in the rain, it's just more prudent for us to close down and keep our snow in good shape," Chris Riddle, Snow Summit's marketing director, said.
Times staff writers Steve Chawkins, Hanah Cho, Jia-Rui Chong, Dave McKibben and Janet Wilson contributed to this story.