The Storm Prediction Center has a new web resource for those who want to look at past tornado events. You can find it at https://www.spc.noaa.gov/exper/outbreaks/. This is a map-based tool that allows you to look at individual past tornado outbreaks and see the ingredients that went into them. I used this to find the tornado outbreak on April 21, 1967 that got me interested in meteorology when I was a child back in Michigan. It takes some time to figure out all the different parameters you can look at, so don’t be afraid to play around.