Shelter for me and the material I'm welding so I can weld outside in the rain if I have to.What do you want the blanket for? to provide a shelter for you when your welding or provide a cover to just welded areas in the event of rain.
Don't get me started.One of those gazebos from your local cut price emporium or the net would do that, £40. protect passersby from the welding if your within eye shot of pedestrians.