The druids and pagans celebrated the winter solstice at Stonehenge on 22nd December and even the weatherman said it was the shortest day. But the actual time of the solstice, i.e. the point at which the north pole tilts furthest away from the sun, was at 5:47pm GMT on 21st December. The day length that day was 7h 49m 41s in London. It was was 1 second longer on the 22nd and 4 seconds longer on the 20th. Shortest day length would have been a little longer on Salisbury Plain, the location of Stonehenge, because it is south of London, but it still occurred on the same day.
Anyone have any idea what is going on?
Unless they are celebrating the 24 hours starting from the closest point I don't know. That still makes the weatherman wrong if he said the 22nd was the shortest.
It is the 21st everyone knows that don't they.
Well obviously they don't, but I thought they would have before I read your story.
Maybe the weatherman just said that the winter solstice was when it was the shortest day, and we assumed he was talking about the day he said it, so he would have been right. In parliamentary terms it wouldn't be a lie, or even an untruth, but merely spin. 
As regards the druids and the pagans, I think it has something to do with the fact that this year the actual time of the solstice was after sunset on the 21st in the UK but I'm not exactly sure why that was important as the shortest day was still on the 21st.
We celebrated after sunset on the 21st. And sure enough, the sun came up the next day, so I guess we did it right, heh. 
Well done! Is your real name Ptraci?
Well, I do enjoy indoor plumbing. Though I have encountered more llamas than camels in my meager existence. None of them was much good at Calculus, as I recall, but then maybe they just weren't into sharing, heh.