looks can be deceiving. you are correct, even down here in the swamp we'll have a low of 21 next friday night. now, compared to back in the day, born/raised in wny, I want to say for myself, the coldest I remember one night was -15 with -60 below 0 wind chill. sure, there were likely colder nights but that night stands out to me. so cold, when the snot was running and you took a good snort, my freaking nostrils froze together. no joke. I was drunk as hell, in a windbreaker. back when I wore a younger mans shoes.
21, with my blood thinned out now, being down south for 35 years, is a tad nippy.