That could be anywhere...

I usually just cover the seat with a shower cap. However, if it's an all day soaker, we have an entrance to our building that is closed with a canopy. I contacted building services about bringing the bike inside and that is not permitted, but they let me park it under the canopy. It works for me.

I have thought about getting a cover, but I don't want to deal with folding up a wet cover when I'm ready to go home.