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.

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.

Newsom and California are frequently the target of Trump’s ire. Some of his most memorable criticisms of the state have been over how it manages its wildlands in the face of wildfire risk. In his first term, Trump suggested California should be “raking” their forests to clean up dead brush and trees.