Protecting UMC cable while charging outside

At my in-laws that we visit perhaps once a month, I’ll be charging via an extension cord, so the UMC will be sitting outside. The UMC will be somewhat exposed - since it is not waterproof, is there an easy solution for protecting the connections and the UMC box from the elements? I was thinking of getting some kind of NEMA enclosure, but wanted to hear what other people have done.