LOS ANGELES (AP) — 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.

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

The charred soil left by the wildfires could create conditions ripe for mudslides because the rain, which will last into Monday, will just run off, forecasters said.

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.

Rain on the way to parched Southern California on Saturday will aid firefighters mopping up multiple wildfires. But heavy downpours on charred hillsides could bring the threat of new troubles like toxic ash runoff.

Weekend rains could bring some relief to Southern California. Here's the forecast and an assessment of how much it will help reduce fire risk.

Southern California is about to get its first significant rainfall in months, bringing desperately needed relief after dry conditions and hazardous winds fueled a series of wildfires in January. The rain could start as early as Saturday afternoon and last through Monday night with the heaviest rain coming on Sunday,