Pyrocumulus clouds form over intense heat sources, like raging wildfires or volcano eruptions. The air above such intense heat is quickly and chaotically forced to rise, which cools and condenses the air’s moisture, forming clouds.

California is only now heading into the teeth of the wildfire season, but the state has already seen nearly three times as much acreage burn than during all of 2023. The wildfires have threatened tens of thousands of homes and other structures across Southern California since they accelerated during a triple-digit heat wave over the weekend.