It seems that anticyclonic easterlies in winter aren’t quite what they used to be these days. Compare today’s 12 UTC observations with those of just over 34 years ago (the 12th of January 1987), on what I always consider to be the coldest day, in England and Wales at least, of the twentieth century. The other big difference apart from the temperature is that most if not all these observations were done manually by observers rather than by automatic weather stations as they are now.
The 1000-500 hPa partial thickness across the south today is no lower than 528 dm, back in 1987 the lowest thickness in the cold pool that crossed the country from east to west during that week was less than 500 dm. If you remember the 528 line was coloured blue, the 510 line brown and the 492 line purple. I can’t remember ever seeing a thickness as low as 492 for many years. I was an observer at Binbrook back then and I kept photocopies of the original thickness charts I plotted and drew up at the time. I don’t know why I never kept the originals, but I thought that I would scan them and add them to the blog before they faded even more. Here’s a picture taken a week or so after the event on one of the roads across the wolds. I do remember when it did eventually warm up by the Saturday of that week the warm air came in from the east.