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

Less than an inch of rain fell in most areas, but it was enough to loosen Los Angeles hillsides charred by the blaze near the Pacific Palisades, where crews working before dawn cleared inundated roadways.

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.