Yep, I keep my grill in the garage. But if not, a covered outdoor porch or something like that is the best solution. I personally would not cover my grill outside. I did at first when I was leaving it outside, but I would go out at noon and a cool morning and pull the cover off and it would be wet inside. We hadn't had rain since the last time I used it. I realized quick that the grill was sitting in the sun during the day and getting all warmed up in the black cover. Then it would cool down and the dew point would bottom out at night and the moist air would condense on the grill. So, it was basically like the grill was getting rained on every evening and then covered to hold it all in.
Unless you have a very well vented cover and one that does NOT go all the way to the ground, you are better off without one. Even then, I would probably still go commando on the grill.
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