Don't you think references to 6 weeks of zonality have now been done to death, it's really not adding anything to this thread IMO and just feeds. 

...........just saying.  

UKMO would keep it cold throughout. GFS still wants to topple and we have to hope for a reload

http://modeles.meteociel.fr/modeles/gfs/runs/2016122712/gfs-0-234.png?12

But yes, temps will be below average and perhaps some snow for northerners.

http://old.wetterzentrale.de/pics/Rtavn3001.gif

GEM still not keen on building heights but it is a little better than the 00z

http://modeles.meteociel.fr/modeles/gem/runs/2016122712/gem-0-240.png?12

maybe ....but neither is the constant posting of inaccurate facts by certain individuals 

Deep in FI - High pressure looks too close to the UK and in the wrong place (too far south and east). So not looking good for snow lovers:

http://max.nwstatic.co.uk/gfsimages/gfs.20161227/12/384/airpressure.png

Back inside 120 (and inside FI) here is the 12z Arpege (French UKMO equivalent-ish) for NYD:

Interessant, n'est pas?

"Papa - ees that an Omega Block?

"Oui Nicole!"

Doubtful this is a blip now with the pattern trending northwesterly after a brief puff of cold air from the north

Nah, not dreadful. Not as much promise as the MetO but still cold for the majority of the time, blocking to the W/NW and the potential for something from the east. 

http://modeles7.meteociel.fr/modeles/gens/runs/2016122712/gensnh-10-1-324.png

Be happy with this outcome

Its clear 144 /168 is as far as one can go, gone through the ENS and its all over the shop with the HP ending up in all manner of places .

Gefs 12z definitely trending colder than the 6z.  Some very cold ones in there 7 or 8 hit -10c for London

I know we can be inclined to keep looking for breakdowns even while snow is a day away but for many lowland areas this is the first opportunity to see snow for a few years so my advice now is to limit FI to +120 and enjoy what's happening in the here and now.

I will be hoping the ECM goes with Arpege.  A bird in the hand is worth 2 in the bush.

Meanwhile here is NAVGEM's take on things at 120 here and 144 below:

No looks like Pete Tong by 192 bugger 

ECM sinker

168hrs

192 hours

Yes, ties in well with previous runs: wintry then anticyclonic then wintry potential at the end again?

Looks set for second northerly to me?  It was never really progged to stay cold after the first northerly, second one may be more potent or may never happen 

GEFS 12z..looking slightly more encouraging at face value. Will need to check individual perturbations.

It looks like a rinse and repeat scenario with the high sinking and we're back to square one. Not disastrous by any means and it'll change no doubt.

Fairly mixed and inconclusive output tonight. ECM12z 216 not without interest!

Yes more members clustering in between the -5 to -10 when compared to the 6z. The control was a real outlier! 

Looking that way Doc at 216 hours. 

Looks good to me.

ECM12z looks promising tonight. T+240 hours.