lol. It must be generational. That's how I, a 49 year old, pronounce
Clara.
For what it's worth, I associate this "CLA-ruh" pronunciation with New
York City / the East Coast. So I've sometimes wondered where I get it from. (I grew up and still live in the Pacific NW, U.S.A.). It could be my mother's Irish brogue. Or it maybe generational, as I said before.
Sometimes I do use the "CLARE-uh" way. But I would never use the "CLAH-ruh" pronunciation.