I considered posting something but the roll of mid-to-low level preparations is quite limited. Given that you may have just minutes warning, and even then you need somewhere to go, and realizing that after a tornadoes the odds are food and water aren't going to be a huge survival issue because tornadoes tracks are narrow, advocating a survival kit wouldn't seem to do much good. Even having one might not do much good if it is swept away.
I figured I could advocate keeping a weather radio on and set up to issue automatic alerts but this has been covered in depth elsewhere. I just don't have much more to say on that.
I considered saying something about building shelters, there are some reasonably inexpensive ways of building a shelter but shelters have been covered. Changes in building codes and methods might useful, many areas have minimal standards for wind resistance that might help in near-miss situations, and discussions on building construction never gather much interest.
And then there is the simple question of what can be said. It is sad and bad, but noting that doesn't change anything.