YMMV, but we never got particularly overheated in Hawaii where we'd need these. We were there in September. It's my understanding that the temperature and humidity are relatively stable year-round, so if that's the case, I can't imagine it being much more humid or warmer than when were there. In our experience, it didn't reach mid-90s with 100% humidity like you might see in Orlando in the summer, where these would be a help. There was also a consistent breeze and we noticed a lot of places are "open air" with no AC, which I think supports the fact that it never gets sweltering there like Orlando does in July.