Officials cautioned that ash in recent burn zones was a toxic mix of incinerated cars, electronics, batteries, building materials, paints, furniture and other household items.

A slow-moving low-pressure system will linger over the Southwest, bringing steady rain through at least Monday.

Rain was falling across Southern California on Sunday, bringing some relief to thousands of firefighters battling multiple major blazes for nearly a month in the Los Angeles area, but also prompting new threats of floods and mudslides across burn-scarred lands.

Rainfall is expected to reach Los Angeles and Southern California this weekend, bringing the risk of mudslides and fire debris flow.

Rain on the way to parched Southern California on Saturday will aid firefighters mopping up multiple wildfires.

Much-needed rain has begun to fall over Southern California, bringing relief to the drought-stricken region but also the threat of toxic runoff.

More rain fell Monday on parts of Southern California after causing mudflows over the weekend, helping firefighters but boosting the risk of toxic ash runoff in areas scorched by Los Angeles-area wildfires.

Rain eased on Monday after Southern California's first significant storm of the season brought weekend downpours that aided firefighters but caused ash, mud and debris to flow across streets in wildfire burn areas.

Southern California’s first rainy weekend of the winter has arrived. The rain event, months in the making, brought steady storms across the region as the Southland experiences drought conditions. The mostly welcome rain began Saturday night and is expected to sustain until Monday evening.