Based on the way things have gone this week;
This time tomorrow, the models will be showing something very cold and exciting
In reality though, I think todays models just about paint the picture ... a relatively cold weekend but average or just below average next week and very wet, rain for most ... but it would be stupid not to rule out anything Wintry especially for the North ...
It is very unrealistic and silly to dismiss cold next week ... average Max for early December is round 8-10'C and the models are showing nothing of the sort ... more like 4-7'C.
As for mid December, it is far too early to be making a conclusion on that yet just on one particular run ... I can guarantee you now, that link you have posted will show a massively changed chart about another 20 times before we get to Mid-December.
Let's stick to what the models are really showing ... and not concentrate on the double figures in the South next week .... Low single figures in the North, East and Scotland is FAR more important.