Can It Ever Be Too Cold To Snow?
You may have heard someone say, “It’s too cold to snow today,” but actually it can never be too cold to snow. Snow clouds form high in the air, where the temperatures are colder than it almost ever gets here in the United States. Two-inch snowstorms have fallen when the ground temperature was colder than 20 degrees below zero. B
It rarely snows when the temperature drops below zero degrees Fahrenheit because the atmosphere is too stable. One of the ingredients for snow is enough lifting of saturated air that snow can develop aloft and fall to reach the surface. When it is said, “it is too cold to snow, ” in reality it means there is not enough lifting of air to cause snow to reach the surface. Even at very cold surface temperatures, significant snowfall can occur. Intense lifting can produce significant precipitation, even at very low temperatures. The temperature higher in the atmosphere can be much warmer than the air temperature at the surface, and that warm air aloft can hold more moist air than the colder air at the surface. And, moisture can be transferred into the area where lifting is occurring through advection (the horizontal movement of an air mass).
As long as there is moisture in the air and a way for it to rise and form clouds, there can be snow, even in temperatures below zero. But very cold air doesn t have much moisture in it, and it is also dense and heavy, so clouds don t form unless the cold air rises up a mountainside or unless the cold air blows across a body of water and collects moisture. Most heavy snowfalls occur in temperatures 15 degrees Fahrenheit or above.
Yes it can, and the expression ‘it’s too cold to snow’ can sometimes be quite correct; but it depends on local conditions. Colder air contains a lot less moisture than warmer air. If the air is very cold; several degrees below freezing, the moisture content of the air is too low for precipitation to form. The place where this is most obvious is in Antarctica; especially in the inland areas. The air there is always below freezing (the warmest temperature recorded at the south pole was -16 C). It virtually never snows at the south pole. The absence of snowfall during the coldest part of winter is one reason why the ski resorts in the Canadian Rockies are so popular, because when the air temperature is around -10 C, it doesn’t snow. This is not always the case though; because if warmer moisture laden air moves into a cold area, it will of course snow, even if the temperature is quite low. The best temperature for heavy snowfall id around -1 C, when the moisture content of the air is highe
