It was -16 F, actual, when I looked at the thermometer this morning.
We tend to be warmer than some of our neighbors because our house is on a knoll and we have tree cover. Cold air is dense and runs downhill and puddles-up in the hollows.
A dense tree-cover is helpful in terms of softening temperature extremes at ground-level. "Cold" is partially the result of the heat-energy stored in items on the ground radiating through the atmosphere to deep-space. Clouds help retain over-night heat. Branches over-head also help reflect some of that heat back.
A secondary effect of heavy tree cover is that the sap and the buds freezing release heat and cause a very localized rise in temperature. Multiply that slight rise a million times and it makes a difference.
Shallow, snow-covered bowls with no vegetation or strctures emerging above the snow are the worst-case scenario for low temperatures. They are parabolic mirrors aimed at deep-space and have no other thermal mass than the human stupid enough to choose to bivouac or have their snow-machine founder there.
Back in the 1970's, when I pumped gas for a living (beer and chick money), we used to say ...snow is better than rain. at least one could brush the snow off. It is negative one here, now, in N.E. Indiana.
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