Yes, we are seeing more variability.
Researchers have identified an eastward extension of the traditional “Tornado Alley” in the central Great Plains. Peak tornado activity has also shifted earlier in the central and southern Great Plains of the United States since the 1950s. It is not yet clear whether these changes are due to climate change.
“Tornado Alley” is expanding eastward in the United States.
Peak tornado activity is starting earlier.
National Oceanic and Atmospheric Administration: National Severe Storms Lab Research on Tornadoes