If the weather does what the Met Office says it will – always a possibility – this week and next Britain will be blanketed with the "earliest significant snowfall" since 1993. But what does that mean?
"Significant," forecaster and Met Office spokesman John Hammond explains is "when snow starts to build up. Two or three centimetres [in a city] could be regarded as significant, but we're expecting double figures – in the Grampians and north Yorkshire we're expecting 15 or 20cm."
The average temperature you would expect for this time of the year in London and Cardiff is around 10C, with Belfast and Edinburgh a degree colder. "Through the course of the weekend, those highs are going to be 2C or 3C, so well below average," warns Hammond.
So why is it happening? Most of the weather that buffets our little island comes in from the south-west, off the Atlantic. "We're seeing a 'blocking' weather pattern where our weather is coming from the opposite direction," says Hammond. "Air is coming down from areas of Scandinavia, and cold air from the Arctic is beginning to arrive. That's why whatever falls from the sky, rather than being wet, will be white in a number of places, into next week."
Is this down to climate change? The beginning of the end? Apparently not. "It's just part of natural variability and what makes the weather such a talking point in this country."
