LOS ANGELES (AP) — After weeks of windy and dry weather, rain has fallen in parched Southern California and is expected to aid firefighters who are mopping up multiple wildfires. But potentially heavy downpours on charred hillsides could bring new troubles such as toxic ash runoff.

Los Angeles County crews spent much of the past week removing vegetation, shoring up slopes, and reinforcing roads in devastated areas of the Palisades and Eaton fires, which reduced entire neighborhoods to rubble and ash after breaking out during powerful winds on Jan. 7.