They are when the temperature is still relatively sane but uncomfortable. But once you get into severe temperature zones, it don't mean shit. Like yeah 90F in Chicago is gonna feel about as hot as 110F in Phoenix because of the humidity. Anything over that is just reeeeeeeel fuckin hot regardless. I just spent a week in the Grand Canyon last summer and you use all kinds of innovative ways to stay cool in the 120F heat. But for some reason in the early evening when it would hit 130F it just felt like an oven no matter what you did. 10/10 trip tho would absolutely do it again!