As festivities begin, many will be dreaming of a “deep, crisp and even” Christmas Day. So here we reveal a number of revealing and, perhaps, surprising facts around snowy Christmas weather that you can share around the Yuletide table.
Ho Ho Hic!
Father Christmas, sitting outside the pub one evening, has one too many pints of beer and falls asleep. When he wakes in the morning, he finds that a metre of snow has fallen on top of him and his empty glass. How many cups of hot chocolate will he be able to make if he lifts the narrow metre-high column piled up on his beer glass, empties it into a kettle and boils it up? Answer: 1 cup! – A metre of snow only amounts to around 10cm of water!
What exactly is a White Christmas?
To most people, yes, snow-covered ground is all that’s needed for the day to be called a ‘White Christmas’. Not so, according to official long-standing records kept by the Met Office. The requirement is for a flake of snow to fall. There doesn’t even need to be any snow on the ground. This is the basis on which most bookmakers decide whether Christmas has been ‘White’ or ‘Green’.
At least one snowflake has fallen on Christmas Day 38 times in the last 55 years. The south of England has not seen snow on Christmas Day since 2004.
Where does our obsession come from?
Charles Dickens has a lot to answer for. Many of his novels paint a picture of perpetual winter frost and snow, no more so than in ‘A Christmas Carol’.
Dickens was born in 1812, amidst the coldest decade since the 1600s. Snowy winters were commonplace. Dickens experienced 6 White Christmases in the first 9 years of his life, including the famous ‘Frost Fairs’ on the River Thames. A snowy blizzard of billions of Christmas cards has followed in the 200 years that have followed.
1927 – The classic Christmas Day Blizzard
The last time that large parts of the UK were affected by heavy snowfall on Christmas Day was over 90 years ago. With perfect timing, rain turned to snow through the day and by Christmas night, most of southern Britain had a covering. Conditions the next day were extreme, with heavy snowfalls and a gale force northeasterly wind, bringing blizzard conditions and severe drifting. Villages were cut off by drifts up to 20 feet and food supplies had to be air-dropped. Transport was virtually paralysed with train services seriously delayed or cancelled. Even in central London, depths of snow were approaching 10 inches.
‘Deep, crisp and even’ is usually no more than a dream. Christmas Day is often green, grey but definitely not white. The warmest Christmas Day on record was in 1920, when the mercury soared to a balmy 15.6C at Killerton in Devon. Typically, temperatures on Christmas afternoon lie between 6 and 9 Celsius. As you enjoy your mulled wine, consider the reality that a thick blanket of snow on the ‘big day’ is virtually a once-in-a-lifetime experience.
Ideal Weather Set-up for Snow
Look out for winds from the north or the east, being pushed towards us by high pressure. Clear skies and frosty weather will pre-condition the UK with a reservoir of cold air above us.
Next we need moister air to arrive into that ‘fridge’ – usually as weather fronts approach. As this moisture hits the cold air, it crystallises into snow clouds.
Is there a trend?
There are no clear trends in White Christmases. They happen infrequently and irregularly. Some decades have more than others. Long-term climate change is likely to make them less likely many decades ahead, but in the shorter term, purely natural variations in weather patterns will continue to determine whether they will occur. So don’t give up!
Games bookies play
People’s betting habits are often based on emotion rather than science, and the bookies know it! An early winter snowfall, weeks ahead of the big day, does not make a White Christmas any more likely – it just makes more people have a flutter. When bookmakers slash the odds against a White Christmas, it just means that more people are heading to the betting shops. So it’s actually best to bet on a White Christmas when it’s very mild earlier in the winter – you’ll get better odds!
Is snow more likely the colder it gets?
Yes and no. Temperatures do need to be close to or below 0C for snow to reach the ground. And you might think that as temperatures fall lower still, the more that snow is likely. You’d be wrong. The coldest continent in the world, Antarctica – where temperatures can fall as low as -60C – is also the driest. It’s with higher temperatures, towards freezing point, that air can hold more water vapour, providing the ingredients for flakes to form and snow to fall.
Bing Crosby and all that
The film was set in in the snowy mountains of Vermont, but was actually filmed entirely in Southern California, with temperatures in the 80s under sunny skies. Thank goodness for artificial snow! However, while the film ‘White Christmas’ was made in 1954, the hit song by Bing Crosby first appeared in the movie ‘Holiday Inn’, way back in 1942.
Christmas at Bethlehem
Nobody actually knows whether snow fell at the Nativity. It’s unlikely. But although Bethlehem experiences a warm desert climate for much of the year, at nearly 800 metres, it is higher in altitude than most of the UK. So winters can therefore be colder than you might originally think. Indeed if you are lucky, you may experience a White Christmas at the birthplace of Jesus. However, ‘in the bleak midwinter’, frosty wind is more likely to make moan back in the UK.
Escaping the Snow
About 5 million people escape the UK each Christmas. Popular short haul destinations for winter sun include Tenerife, Lanzarote and Fuerteventura, while flights to Cape Verde, Jamaica, the Dominican Republic, Goa and The Maldives are strong favourites for people taking long haul sunshine breaks. On Bondi Beach in Australia, Christmas afternoon will typically bring temperatures in the 90s Fahrenheit.
Lapland – A snowy guarantee!
If it’s guaranteed snow you’re after, then you could spare Father Christmas and his reindeer a journey and pick up your presents from their own backyard. One thing’s for sure – you’ll be certain of snow. The average temperature is -6 Celsius, but on some nights it can fall as low as -30! A Green Christmas has never been recorded here. The only catch is that it barely gets light all day!
And this year? What are the chances of a White Christmas? Well, as ever, we’ll only know for sure on Boxing Day!