I stored my hybrid on a covered balcony in Greenbelt Maryland and it rusted in no time. Not enough rust to destroy the bike but enough that I had to scrape rust off a few places.

Also, when I didn't ride it for a few months a group of wasps made a nest in the frame. to get them out I had to spray chemicals into the frame and then run back inside to avoid the hoard of wasps that were trying to defend their home. Took awhile to get them all out.