We are having an outdoor summer wedding in southwestern Colorado...we are trying to figure out groom attire. July will still be pretty hot, even in CO. I was thinking of just a suit instead of a tux, but my fiance still thinks that will be way too hot. We are trying to figure out something nice but cool...is khaki slacks and a long sleeve short too informal? He mentioned wearing short sleeves, but I'm not sure if there is any way to make that very "wedding appropriate" lol.....any ideas???? Thanks!!!!