Tonight for my ward home evening, the activity was the 'polar bear plunge'. The first counselor shoveled the snow off the pool cover, opened up the shallow end, and a group of us gathered around in swimsuits, shorts & t-shirts, and in one case - jeans & a t-shirt. I was one of the group.
I had done this while living in Vegas a few times, but didn't think I could use that as a way out while living in Utah.
Verdict: cold! But not as cold as I thought it would be. As soon as I got out I was feeling warmer and tempted to go back in and try it a second time. But I didn't.