Heck you barely need to step outside in Vegas. I've been there multiple times and the temperature could have been 60 or 120 and I doubt anyone around me would have known the difference.
I've been to Vegas at all different times of the year. Folks there definitely notice when it's not 120; they were wearing jackets, hat, and gloves when it was in the 50s at Christmas in 2005.
I was there for Google Next in April and it was hovering between 95 and 100 and I was comfortable in jeans and a polo, but I would have been just as comfortable at 60.
Living in the Upper Midwest, I find it so interesting that we deal with -40F to >105F (sometimes with 80 degree temperature swings in a day or two; going from -40 to +40) just fine but folks in places like Los Angeles, Las Vegas, and Tampa, FL cannot seem to handle even 10 degree swings. Crazy.
I assume you mean 80 degree real feel swing. And yes, how folks react to temperature is relative. First 45 degree day in Minneapolis in Fall and folks are wearing coats and jackets. First 45 degree day in Spring and people are wearing shorts, flip flops, shortsleeves, and some go shirtless.
