I need to locate it but Tornado Alley as it is described has seen more frequency of tornadoes encroaching further east relative to its traditional alley of NE, KS, OK, TX.
I stumbled upon the chart when I was talking with some guys in New England that I talk to each week after having successive tornado warnings during our weekly call.
It wasn't some seismic shift, but it told me there are comparable #s of tornadoes in IN, IL, OH, TN, MS, AL
Recognizing there are a lot of ways to measure and evaluate the data.