Is Arizona really that HOT? I would like to move there, but wonder if it's too extreme, please read my detail

I live in CA. I love the western part of the U.S, I love the canyons, mountains, ofcourse coastline. (I know AZ has no coastline) but I have to get out of expensive CA, I was looking at some apts and home properties in AZ, it is absolutely Gorgeous! I love the type of architecture there. And I definitely love the lower cost of living. I am just scared to death of those high temps though. I hear a lot of seniors live there, how in the world can they deal with it? What do locals do when it is 110+? Is the heat a danger to children at school? Will a place like AZ be a fireball with global warming? Please give me your opinion, I can't afford to live in CA anymore. Thanks