I was shocked watching this show from how many places didn't have tornado sirens back when this outbreak occurred. Xenia, Ohio did not have sirens. I know we had sirens here in the Toledo area in 1974, but thinking back I don't believe we did in 1965 during the Palm Sunday tornadoes.
And, to see how antiquated the NWS was back then. A tornado warning wasn't issued until one was already on the ground, and sometimes much later! It is a wonder 1000's weren't killed. In the show on tonight they credited the '74 super-outbreak for stimulating the upgrades in radar and communication systems to put out weather info.
We have far more available to us, the amateurs of weather, than they had during the outbreak of '74. Amazing. I guess it's that way in a lot of fields, like amateur astronomy.
Mark