As December arrives the Met Office knows it will get one question more than any other – “Will it be a white Christmas?” And some people are extremely optimistic about just how early they’ll be able to find out.
A spokesman said: “We actually start getting questioned about this in October (sometimes before), but the short and disappointing answer is; it is still too early to say. It’s not until the week before Christmas that we should start to have an idea about the chances of seeing any flurries on the big day.”
And even then it isn’t an exact science despite what other organisations might say. For while some predict it will snow – or not – much earlier this is not going to be accurate. The spokesman added: “They often use one-off, individual forecasting model runs to suggest what weather ‘might’ be on the way.
“However, the truth is that single model runs are not reliable enough to work out a detailed forecast, they are just one part of the wide range of information needed to provide a full forecast picture.” Met Office Meteorologist Aidan McGivern said: “What meteorologists actually do, is rather than cherry pick one computer model run for more than two weeks’ time, the computer models are run lots and lots of times and then we can pick out areas where they are agreeing and areas where they are disagreeing. Then we can talk about likely weather patterns and less-likely weather patterns, common themes and so on.”
So while the Met Office’s long range forecast looks further into the future meaning it now covers the festive period it is a long way off from being sure. It said: “Yes, our long-range forecast now covers the festive period but, it isn’t a detailed forecast like our five-day forecasts.
“The long-range forecast gives a broad description of the weather that is likely to be affecting the UK. It gives an indication of ‘how’ the weather might change or be different from normal (like getting warmer, colder, wetter or drier for example), but it doesn’t go into too much detail as the story is always changing.
“This is because when looking at forecasts beyond five days into the future, the chaotic nature of the atmosphere begins to play a larger part. Even small events currently over the Atlantic can have potentially significant impacts on our weather in the UK in several days’ time.
“Therefore, whilst our long-range forecast gives a prediction as to what the weather may be doing over the Christmas period, we have to acknowledge that many outcomes remain possible, and it won’t be until much closer to the time that we can say with any more certainty.”
How likely is there to be a white Christmas in 2024
It says: “For the Met Office to declare a ‘white Christmas’, a single snowflake has to be observed falling on the 24 hours of 25 December, by either an official Met Office observer or by a Met Office automated weather station. This is because it needs to be officially verified both for our climate records, and also to provide consistency and certainty.
“Climatologically, Christmas Day is like other winter days in the UK, where the weather is strongly driven by the air mass we are influenced by at the time and the behaviour of the jet stream. Since 1960, around half of the years have seen at least 5% of the station network record snow falling on Christmas Day.
“This means we can probably expect more than half of all Christmas Days to be a ‘white Christmas’. However, the Dickensian scene of widespread snow lying on the ground on Christmas Day is much rarer.
“There has only been a widespread covering of snow on the ground (where more than 40% of stations in the UK reported snow on the ground at 9 am) four times since 1960 – in 1981, 1995, 2009 and 2010.”
When will we know for sure?
The Met office says: “We can accurately forecast if snow is likely on any given Christmas Day up to five days beforehand.” So in theory you should be able to have a good idea on December 20 – but then there are never any guarantees.