Zero degrees with a strong wind is twice as cold. I'm reminded of a story I read in Chemistry book a long time. Somebody persuaded the Czar of Russia to have all the Army's buttons made of pure tin. There is one problem though, which was not known to the button makers. I think it is at forty below zero Centigrade (which happens to be same as forty below Fahrenheit), pure metallic tin becomes a powder!
which to me evokes a ludicrous visual image of a long column of half frozen Russkies having to hold up their trousers with both hands.