Here in MT an evaporative cooler can make a big difference. During the summer there are many days with dewpoints well below 60°. Lots of tractors, swathers, combines, & trucks with swamp coolers back before compressor type AC units got better and more commonplace. Aside from the hassle of packing 20 gallons of water a day, they worked just as well as the freon ones -- here.
But this is NE Montana and not the damp midwest or coastal regions.