I'm in my early 40's, live in the US (northern midwest area), and also have family in the southern states (Alabama, Mississippi, Arkansas), and have never seen

I'm in my early 40's, live in the US (northern midwest area), and also have family in the southern states (Alabama, Mississippi, Arkansas), and have never seen a bomb shelter at any family or their friends places -- never even heard anyone talk about them either. However, almost everyone had a storm shelter -- typically a cellar dug in the side of a hill (they get a lot of powerful thunderstorms and tornadoes). I could see them doubling as a bomb shelter back in the day, but I never heard them referred to as anything but a storm cellar.