I would second the recommendation for Mac's Airplane Covers. I have Molly in a hangar now, but for several years she was outside, with one of Mac's covers on her. I think he is a little cheaper than some places, and the covers work great. I had an issue with a seam that came loose, and they fixed it even though the guarantee was expired. The covers have enough "bulk" to them that you can, with a little effort, get them on even when it is windy (personal experience)!