Can it ever be too cold to snow?
I know you must get this question occasionally: Can it ever be too cold to snow?
— Tad McClarren, Palos Heights
No, it cannot. All that is required for snow to occur is the presence of water vapor in the air — and some water vapor is always present — and a mechanism to chill the air below its saturation temperature. Water vapor will condense out of the air when that happens, forming ice crystals if the temperature is below freezing.
Consider the situation in Antarctica, Earth’s coldest continent. On May 18, 1972, at the South Pole station, with a high temperature of 57 degrees below zero and a low of 76 below, one-tenth of an inch of snow was reported. This was not very much snow, but it was snow nonetheless. That data, by the way, come to us from Ed Jessup, a now-retired meteorologist in charge of the South Pole station.
All that is required for snow to occur is the presence of water vapor in the air.