What does this person mean "Marx's definition of Historical Materialism"?? Like even on its face, saying there is no "historical materialist" conception of the tornado is just silly. Obviously there is a historical materialist development of a tornado. As the environmental conditions developed from the formation of the planet to today, the conditions that shape the formation of tornadoes were created. Even if that isn't historical materialism strictly, you can still measure and chart the size and strength of tornadoes over time as human industrialization developed. If historical materialism is strictly about human social and economic development over time on an objective bases, you can still chart the knock on effects of that social and economic development in other areas of material life. Humans do not live outside of nature so... Human activity obviously has an impact on the environment and this includes the weather!