A question meteorologist get asked all the time during the cold winter months is "can it ever be too cold to snow"? Well, the short answer is no.
The ingredients for snow are:
1. A temperature profile that allows snow to reach the surface
2. Saturated air
3. Enough lifting of that saturated air to allow snow to develop aloft and fall to reach the surface
The phrase "it's too cold to snow" probably originated as a misapplication of the relationship between temperature and the maximum amount of water vapor that can be in the air. When temperature decreases, the maximum capacity of water vapor that can be in the air decreases. Therefore, the colder it gets the less water vapor there will be in the air.
Most heavy snowfalls happen with relatively warm air temperatures near the ground -- usually at 15 degrees F or above. When the temperature drops into the single digits, or below zero, heavy snow is unlikely. That's not because it's too cold, but because its too dry. When temperatures are that low, the air's capacity for water vapor becomes very small.
Experts say only at absolute zero would snow become impossible. Along with everything else.
Beginning in the evening hours of Oct. 8 and continuing through Oct. 9, the peak of the Draconid meteor shower will become visible to eager stargazers.Read Story >