A/C on!? That sounds about right. I did, too, on the way home Saturday afternoon.
It was in the high 80s in Phoenix, high 60s by sundown in Tucson, and in the mid-40s by the time I got back home in Sierra Vista. (1100’ to 5000’ in 3 hours helped drop the temps!)
What a difference 24 hours makes, huh! Or even a few hours drive. It was darn chilly when I left OKC.