Here in Madison, Wisconsin. Everyone is staying in, so I see a danger of keeping too warm, losing one's acclimatization to the cold, so that when it warms up enough for some nice winter days outdoors — back to, say, 18 above — that will feel chilly. Perhaps we'll take a walk around the block at some point in the interest of preserving winter acclimatization. There's also the interest in being able to say that you remember when it was 18 below and you don't just remember it from reading what the temperature was from inside the house: You remember how it felt.
UPDATE: Meade reports that he stood outside, without a coat, but with his hands in his pockets, for about a minute. He says it was "painful." So I step outside, without a coat, with sleeves pulled down over my hands. It's surprisingly pleasant. Predawn, 7:15. Quiet. For many years, I'd believed that what's distinctive about temperature lower than 5 below is that when you breathe you feel the moisture in the air icing up inside your nose. You need to wrap a scarf around your face to create an antechamber for the air to make it breathable. But I had no scarf, and the breathing was fine. It felt good. But the door was at my back, and I knew I could withdraw into the warmth at any second. How much that changes the perception of cold!
The weathermen can tell you how much the element of wind affects the perception of cold, but they cannot calculate the effect of the mental element, which, even if it could be measured, varies from person to person and even within one person constantly changes. Our powers of mind enable us to get out and experience nature in winter, to the point where we might actually damage our bodies. The mentally strong have their stories of frostbitten hands and feet. It is possible to get hurt and even to die. The powers of mind must also be expended to take proper precautions, the best of which is access to an indoor refuge.
By the way, speaking of factors the weatherman doesn't report when they tell you what the wind makes the temperature feel like, how about the effect of wearing a woolly hat, a scarf around your face, insulated mittens and boots, and a very warm, long coat? They tell you the wind chill factor, but never the coat-warmth factor. The wind-chill factor is based on the feeling of blowing cold air over naked skin. To really know how it feels, I need to redo my front-stoop test naked. But dawn has now struck, and my test results would be crazily skewed by the public-nakedness-embarrassment factor.