Hi @nathanu .  I'm in Maryland, and, believe it or not, the humidity here rivals that of Florida.  There are many days that our weather forecasts make that comparison and frequently remark that we are hotter/more humid here than in Florida or Louisiana.  In fact, this last 5 days it has been over 90 F, with dewpoints around 75.      M-U-G-G-Y

In the summer, I wear my buff as a doo-rag (no need to soak it beforehand, sweat will do that in no time).  I wear lightweight breathable and quick-drying shorts, like Outdoor Research Ferrosi, Patagonia Quandary or Eddie Bauer (sorry REI) Guide Pro, and lightweight shirts like Outdoor Research Echo, Patagonia Capilene Cool, or REI Sahara.  I have different, lightweight hiking boots for summer.  I agree completely with @Dad_Aint_Hip about sock liners.  Game Changers!

And, whether I plan on it intentionally or not, the heat and humidity tend to force a slower pace.  I carry extra water in a hydration bladder which I fill with ice.  Not only does that taste better, it acts like a mini air conditioner against my back.  And, since we are blessed with an abundance of waterways, I never miss the opportunity for a quick dip, or at least a wade, through one of them along the trail.

Stay cool out there!

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