Data shows that the conditions needed for the development of dangerous supercells storms that bring tornadoes are generally shifting east of the area traditionally identified as "Tornado Alley" in the US. Using climate change models scientists were able to identify that not only are the areas that experience these supercells shifting — but the frequency and intensity of the supercells will make this danger worse in the future. These supercells will bring tornadoes, hail, and extreme rainfall to a new population in the US.
While there are concerns about the linkages between climate change and extreme weather, it's much less clear when it comes to tornado activity. Some scientists will say that increasing temperatures lead to unstable weather that spawns tornadoes, but they can't prove it with available data. With less than 10% of severe storms resulting in tornadoes, observations are unable to strongly support the hypothesis that climate change is a driver of the increase in deadly tornadoes in the US.