Wildfires tearing through Southern California have already burned tens of thousands of acres and structures down. Now, another threat is facing the area: fire tornadoes.

As if they aren’t already facing enough, firefighters in California also could encounter fire tornadoes — a rare but dangerous phenomenon in which wildfires create their own weather. The National Weather Service warned Tuesday that the combination of high winds and severely dry conditions have created a “particularly dangerous situation” in which any new fire could explode in size.