No more white Christmases?
With 15.3C recorded at Heathrow, it’s certainly one of the warmest Christmas Eve’s in recent years – but the warmest on record was in 1931 when 15.5C was recorded in Aberdeen and Banff.
That was obviously some time ago, although that may have been down to mountain effects (the Fohn Effect, whereby air descending downwind of a mountain range is warmer than on the upwind side),rather than a more general warmth.
It is hard to draw any real conclusions, especially where records for a single day are involved.
But the relatively high temperatures are consistent with the general warming we’ve been experiencing (it looks like this is the first year the Central England Temperature has been above the 1961-1900 average in every month, for example), coupled with a south-westerly flow, thanks to the position of the jet stream.
Does it mean no more white Christmases?
No – firstly, it looks like there’ll be snow over the northern Scottish hills this Christmas, while more generally, changes in the jet stream may put us on the cold side in future years, bringing an increased risk of snow.