If it's 80 degrees and pouring, my suggestion is that you don't really need to worry about being wet. (And staying dry in a torrential rain such as you describe is well nigh impossible regardless.) You'll be warm. Instead, to avoid waterlogged feet, try a cycling sandal like these: http://www.teamestrogen.com/prodKE_1008668.html Your feet and the shoe will dry out much more quickly.