A wet pattern will bring periods of rain and showers to Southern California, dropping an inch or two in the Los Angeles region — the most to fall since mid-April. It will be key for firefighters continuing to battle flames.

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.