The temperature of hot girls is not something I studied. However, the effect is also found in stupid young males, I think. Yesterday, I went to get a haircut, it was pretty cold and I wore a warm jacket and knit hat. Waiting for my turn, there was a late teenage male there who was wearing thin shorts, a tee shirt and flip flops. Even though you had to walk through cold wet parking lots. See that all the time. Kids waiting for the school bus in the cold, not wearing jackets.
So it's not just females but posturing males.