Here in Arkieland, it's hot and VERY humid. I sweat like a pig and wear a cycling cap, Headsweats liner or headband under my helmet. I thought the cap would be hot, but really can't tell much difference and enjoy having a short bill above my shades to keep the sun off my face. My wife scoffed, but now she's glommed onto one of my Assos caps. I thought I was just getting very dirty on my rides until I wiped off the grime and found it to be mostly salt.