I read the article thinking about wind chill and its corresponding risk of frost bite. Then I saw the temp was 10C, so it must have been similar to late spring skiing conditions. Cool but probably not dangerously cold. It's a wonder his skis could slide over the wet snow at all.
Naked skiing is not impossible. Springtime when sun warms a lot and there is still snow naked skiing is nice. There are plenty of pics people doing that.
Here is another article on this story, includes a reporter's photo. Austrian Star Skis Nude After Bet , Schoenfelder (the skier) said "I am happy, though, that the pains have eased up and that it was not cold when I honored my debt." Thus he had no frostbite worries
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