GEM is very nice although falls for the Dec 2010 problem of going too far west and allowing milder air to sneak into the south. 

ECM looks tasty but for real phwoar! value then the GEM is pick of the bunch - check out the T+240 chart at the end!

Clearly outside of the reliable but fun to look at nonetheless. FWIW snow in the South starts from roughly 6 or 7 days out and so if it's still showing tomorrow teatime then I may start to pay a little more attention. 

JMA not too good south of the border.  Uncertainty remains.

GFS Op - agrees with FAX and brings the N-ly down across Britain by Sat 3rd esp marked on the E coast. It only lasts a couple of days before HP is resurgent form the SW, drifting E-wards across Britain 1035mb Wed 7th, pushing the N-lies off to the Baltic and introducing a W-ly regime. Then on Mon 12th LP breaks away from Greenland and is centred 970mb Rockall with some rather cold polar maritime circulating around it.

ECM - agrees with GFS to Mon 5th but then persists with keeping the cold air and LP over Britain (970mb London Thu 8th) and although the LP moves off to the NE, cold air stays over Britain until Mon 12th. As Ally says above, prospect of a big snow dump on Thu 8th - confirmed by Sod's Law, as I'm supposed to be travelling to Oxford on the Friday!

GEM - different again after Mon 5th as LP, not HP,  moves up from the SW (trough from Azores to Cornwall 995mb Tue 6th) beginning to introduce S-lies and push cold air back to Scotland and beyond.

AIFS - London, maxima about 5c to Sat 3rd with a brief cold plunge at New Year, then prospect of ice days to Thu 8th before back to 5C with frosty nights; very little rain. Edinburgh, temp profile similar, but everything happening a day or so earlier; significant rain Thu 8th. In both cases 'rain' looks more like cold rain/sleet than snow.

GEFS - generally, good agreement on temp mostly down to 5C below norm until Tue 8th (a touch milder in the west at first), when back to just below norm and less agreement. Chances of rain or borderline snow from Fri 2nd onwards (less borderline on the E coast, small falls likely in first week of January). 

A cold spell likely from the New Year, backed up by BBC forecasters who don't normally commit themselves this far in advance. But as to how long it lasts, choose you favourite model!

Uncertainty does remain indeed, however that is the first time in a very long time I have seen the JMA used to highlight uncertainty when there is broad agreement across much of the rest of the output. What’s next, revival of NOGAPS to point out it looks like a breakdown at day 10?  😀

Seriously though, the consensus on the overall pattern across the models for the start of the new year is almost as high as I have seen it for any scenario in recent months. (The usual caveats apply of course).

https://www.meteociel.fr/modeles/gfs/royaume-uni/precipitations/162h.htm 

https://www.meteociel.fr/modeles/ukmoeu.php?&ech=168&mode=0 

https://www.meteociel.fr/modeles/ukmoeu.php?&ech=168&mode=2 

I much prefer the low much further south as gfs especially control looks bitter with no push from the south with snow showers becoming heavy at times

https://www.meteociel.fr/modeles/gfse_cartes.php?&ech=168&mode=0 

https://www.meteociel.fr/modeles/gfse_cartes.php?&ech=168&mode=2 

On we go all to play for

Lengthy cold snap with snow just about anywhere but favoured spots preferred, hard frosts, snow to rain event before rather not think about it ...

Very wintry medium term outlook ( for the modern era)

It'll be interesting to see if GFS sticks with not developing HP over Greenland as much as the Euros (and GEM) are currently doing or if they drop the idea. GFS often seems the most keen to inflate Greenie HPs, so it's slightly perplexing why it's not doing so now.

GFS is still very cold into the mid term, with a cleaner feed (IMBY) for example than the UKMO, but whereas the Euro setup runs the high risk/reward scenario of milder air and LPs trying to encroach from the south west, the GFS solution risks the core of the HP slowly sinking too far and milder air rolling in over the high.

At T180 regardless of the differences it's a lovely run, with the usual shower distribution you'd expect from the setup and appreciating it's 'JFF' but significant snow building up over some parts:-

https://www.wetterzentrale.de/maps/GFSAVGEU06_144_1.png 

To be pedantic I think it’s a day of two maybe beyond that point. The colder synoptics look favoured before then.

This is the 180 hr 06z GEFS mean

 And the 00z ECM 192 hr  mean 

This morning... it's showing that day as totally dry 

I did take a screenshot for posterity but can't login to the other part of TWO to upload it

Shows the knife edge that our chances sit on, and the impacts of even moderate changes in the output.

If these verify, we could be on the cusp of something special, but still early days and I won't be making the mistake of telling friends and family and hope that Brian doesn’t dig out the images of polar bears (those who are veterans of TWO knows what that means 😅😅).

https://www.wetterzentrale.de/en/topkarten.php?map=1&model=gfs&var=1&run=6&time=240&lid=C00&h=0&mv=0&tr=6#mapref 

Happy Big 5 zero Mooms,  may it be a snowy year for you

Yes I think the south is likely see a similar picture as 2010 (but watered down), with mild air encroaching from the southwest and keeping us out of the freezer. Before that it looks good for a day or two of cold. 

Thank you. Fingers crossed 🤞