17-year-old Minnesota teen Rudy Hummel has been sleeping outside since June, and he plans to continue to do so for a full year.

Recent temperatures have dropped well below zero, but wrapped in multiple layers in his snow cave, Hummel says he manages to stay warm.

What started as a personal challenge is now also raising awareness about the plight of the homeless, and Hummel says he plans to organize a fundraiser for organizations the help the local homeless community.

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