Scopes still work well in the rain. Still, one of the best investments I've made is a set of scope caps that pop open silently with the touch of a finger. They make it easier to carry the rifle without worrying about scratching the lens or getting mud or snow on the lens. I especially like not having to worry about the snow when hunting in NW Wisconsin.

I don't recall the brand of caps that I use, but they were pretty cheap - maybe $10 or $20.