Bing Crosby may have been dreaming of a white Christmas, but it seems such nostalgia might end up becoming a thing of the past in the UK. Not only do records reveal that some parts of the UK have at times gone decades without a yuletide flurry, but experts say the chances of a white Christmas are becoming ever smaller as a result of the climate crisis. According to the Met Office, a Christmas in the UK is white if even one snowflake is observed falling somewhere in the 24 hours of 25 December. Last year was, technically, a white Christmas in the UK, though none of the Met Office observation stations reported snow lying on the ground. “For widespread and substantial snow on the ground on Christmas Day, we have to go back to 2010,” said the Met Office spokesperson Nicola Maxey. Between 1960 and 2020, London had six white Christmases, Cardiff had four and Belfast and Edinburgh each had 11. Within that period, however, London had stretches of up to 20 years without yuletide snow. And it seems Crosby’s dream is becoming ever more remote. “Climate change has brought higher average temperatures over land and sea and this generally reduced the chances of a white Christmas,” Maxey said. Experts have found that the chance of snow on Christmas Eve has increased in some southern and eastern parts of England, and they say part of the explanation could simply be that such an event is so rare that even a small number of snowy Christmases can sway the trend. The rosy association between Christmas and snow is somewhat flakey. Around the time Bing Crosby was crooning in the early 40s, a frosty yuletide was far from a distant memory: the winter of 1939-40 was one of the coldest on record. The winters of 1946-7 and 1962-63 were also notable for their widespread snow. Further back, snowy Christmases would have been even more frequent: the little ice age that chilled the North Atlantic region from the 16th to the 19th century gave rise to frost fairs on the frozen River Thames and some winters when temperatures averaged 0.5C. Such chilly conditions could well have inspired writers such as Dickens to conjure up what are now quintessential festive landscapes. “There was a cluster of a few really cold Christmases in the 1830s and early 1840s that preceded the publication of A Christmas Carol in 1843 – maybe contributing to our ongoing national association of snow and Christmas,” Maxey said. But not everyone would have looked back on them with nostalgia, given the impact of conditions on those living in poverty. Georgina Endfield, a professor of environmental history at the University of Liverpool, said: “Everybody thinks ‘oh, wouldn’t it be lovely and romantic’, and actually it was filled with hardship.” She noted in particular that the bitter winters of 1794-95 and 1813-14 took place against a backdrop of food shortages because of the Napoleonic war. Endfield said there was a bias at play. “It’s the dramatic, and the extremes, that tend to get benchmarked and culturally and materially inscribed into social fabric,” she said. Timing matters, too. The switch to the Gregorian calendar in 1752 meant 11 days were removed from the month of September that year, resulting in 25 December in effect being brought forward to earlier in the winter, where it remains. “Christmas comes at the beginning of the season for snow,” said Maxey, noting that wintery weather is more common in January. For now, it seems the jury is out as to whether this Christmas will be white in the UK, with Maxey noting that such predictions are notoriously tricky. “There is often a fine line between who sees snow and who sees rain,” she said. “Sometimes just a fraction of a degree Celsius change in temperature can make the difference between rain or snow falling, making forecasting snow weeks in advance extremely difficult.”