I would say most of lowland Britain has already had some fairly wintry weather. I'm above average for number of frosts by mid December, I would have thought.

ECM is interesting, high pressure is quite reluctant to leave the southern part of the country, and keeps fighting back. Might not be quite as unsettled as I was fearing.

"Kiss my shiny metal butt" as someone once said.

In all seriousness, it is a statement of fact.  Are you arguing that the days don't  lengthen after 21 December in Britain?

21 December is the winter solstice.

Here is a link so you can learn more about it

https://en.wikipedia.org/wiki/Winter_solstice

A chilly few days then unsettled (maybe some transient northern snow) and then unsettled and possibly uncertain.

Agreed. Hopefully the unsettled conditions will cease in time for Christmas.

I'm sure most of us would welcome a mild and benign Christmas and New Year. Its so much easier to get about, see the family and get out for nice walks during the holiday break 

I think you just massively (and inadvertently) ramped the remaining 19 days of December as delivering snowfall to lowland Britain

Interesting models tonight it you're squinting at them with your optimistic glasses on - lack of Eastwards progression of LP systems, as has been shown for a few days now, reluctance of HP to the East to give in and some signs of ridging towards Iceland/Greenland. Not coming to much at present, although there's still the possibility of some transient snowfall for some this weekend but potential down the line.

Of course if you're in pessimism mode you'll point to the fact all the above means for the UK for most of the model runs is varying degrees of milder and cooler unsettled stuff, with no strong signal for anything properly cold as far as the eye can see.

I'll plant myself (as usual ) in the former camp and wait and see if HP can get a foothold anywhere interesting and last long enough to drag some cold air in for the last week or so of the month.

 Absolutely and if we can’t get a traditional White Christmas that scenario would be my next favourite option (followed by several feet of snow in the new year )

That intense High centred over NW Russia in the latter stages of the 12Z ECM operational run is quite impressive. At T+216 it looked as if it might just spread its influence as far as the UK, but by T+240 the Atlantic seemed to have won out, at least for the time being. However that High did bring a lot of properly cold air over Russia and to a lesser extent over Scandinavia, something that I don't really think we've really seen previously this winter. Of course that hasn't actually happened yet, but I think the run gives some reason to be hopeful regarding possible developments further down the line.

i just can't understand why anyone would want sunshine on Christmas Day. I'd take fog, rain, overcast and cool over sunshine every time. We get plenty of that sunshine stuff the rest of the year

Do you never read Richard’s posts? 

I'd take sunshine after a sharp frost and a sub-zero max.

Does "possibly" make it more or less likely to be uncertain? 

 I have absolutely no idea why I wrote that bit! 

Can I blame autocorrect? 

this I will accept

long way to go anyway in weather terms

GFS 18z delivers another completely different evolution but with a recurring theme of a relatively quiet Atlantic.  

In the shorter term it looks like the Atlantic breakthrough trumpeted to be here by now by a couple of seasoned contributors has been pushed back to later on Saturday.

It sounds like a cliche but the models do seem to underestimate the strength of blocking at times.

It’s almost as if GFS has sniffed a major pattern change but can’t work out what to do with it.

might be the warming or just the fact the Atlantic is not as strong so the blocking stability is being underestimated 

ECM 12z ensemble for London

As you’d expect, decent agreement out to Monday/Tuesday on the general pattern, with a return to more normal temperatures. Beyond day 10 there’s a clear cooling trend due to smallish clusters showing cold to very cold conditions but an awful lot of uncertainty.

Now there's a nice chart to see for Christmas Day - the 0z GFS serves up snow for the east and SE:

(Click for full size)

Lets hope it's not gone in 6hrs!

Certainly a changeable outlook at the moment with colder weather never too far away as we approach the big day!  Sadly the current brief easterly will not win out but it does show how close we are getting to something more wintry in nature.  Certainly feels chilly outside this morning! 

Op and Control diverging wildly at & after Xmas in the ensembles for Brighton, the former above all the individual runs and the latter below, some 20C apart!

Very progressive ECM this morning with the charts taking on the 'zonal bowl' look as we head towards Xmas.

Doesnt look true zonal to me ian that big high is blocking progression west to east .

I think you seem to have lost the ability to tell it as it is not as you would like.

thought GFS was best in this situation- selective!!