Why didn't I have to scrape the car windscreen this morning?
It was bitterly cold this morning, so you'd expect to have to spend 10 painful minutes scraping ice off the car windscreen.
But, although most people woke up to at least a dusting of snow - in many parts it hadn't frozen.
Happy days!
So why is that?
A snowflake is a particle of dust which water droplets cling around, forming an ice crystal.
The size and composition of a snowflake depends on the type of air it falls through.
If a snowflake falls through air which is just above zero degrees, the edges of the ice crystals start to melt, the snow flakes clump together, the flake gets bigger and bigger and as it falls on the windscreen, it freezes.
If, like today, the air is very cold and dry, the flakes haven't got time to clump together and subsequently freeze.
The flakes fall to the ground as powder snow. That's the snow which makes a crunchy noise, forms snowdrifts - and is hopeless for making snowmen.
But it means you get ten minutes more in bed!
Here's Des Coleman with everything you need to know about snow:
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