Well it is IF you are on private ground. Public I think it would get destroyed.Public land has its own set of rules of when yo can put up a blind. Private you can do anytime at least in WI.
The material is such that it will help. I like a back and a roof on my blinds but make so I can sit back in the shadows. We are not completley enclosed. But a back and partial roof does help protect us from wind and weather.
JW