News What is a fire tornado? ‘Extreme fire activity’ sparks rare weather warning at Loyalton Fire near Reno. August 16, 2020Jordan Culver, USA TODAYComments Off on What is a fire tornado? ‘Extreme fire activity’ sparks rare weather warning at Loyalton Fire near Reno. Fire tornadoes are formed similarly to tornadoes caused by severe thunderstorms, except extreme heat from a wildfire is the cause.