Emma Lee-Potter

The Christmas lights are twinkling in Oxford Street (Jessie J switched them on in her indomitable style this year), the John Lewis Christmas ad is melting hearts and the glossy magazines are stuffed full of turkey recipes.

Yes, the countdown to Christmas 2013 has begun. And with five weeks to go (eek) till the big day the speculation about whether we’re going to have a White Christmas has begun.

But why are we all so obsessed with the idea of a White Christmas?

When I canvassed Twitter friends, some put it down to the Bing Crosby effect (White Christmas is the best-selling single in history, with more than 50 million copies sold worldwide), while others reckoned it’s because everything looks so much prettier when it’s blanketed in snow. “It’s like the perfect fairytale ending,” said one.

But even though we often associate the festive season with sledging and snowball fights, snow at Christmas isn’t actually that common. Not in the UK, anyway.

Records show that snowflakes have fallen on December 25 around 38 times in Britain over the last half century, but it’s rare for us to get a widespread covering of Christmas snow.

Then again, the definition of what constitutes a White Christmas is open to debate.

“For many people, a White Christmas means a complete covering of snow falling between midnight and midday on December 25,” says the Met Office.

“But the definition used most widely, notably by those placing and taking bets, is for a single snowflake to be observed falling in the 24 hours of December 25 at a specified location.”

I was so intrigued by this idea that I decided to write a novel about two rival TV weather forecasters who have a bet on the chances of a White Christmas.

So will the snowflakes fall on December 25 this year? Judging by the arctic conditions on the way this week in the UK I think we could be in luck.

PS. If you’d like to read my festive ebook, White Christmas, you can download it at Amazon.