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@Jstroke, I am in MI and have had my Blackstone for nearly a year. I bought the vinyl cover, but otherwise totally exposed to the elements. No rust yet. A little water may collect on the griddle surface, it just bubbles up on the seasoned surface. As noted earlier you will want to place something under the cover in the midlle of the griddle to create a slight tent so water runs off instead of collecting and puddling. The griddle is just fun to use.