Very roughly from GEFS 12h, 50: 50 split Cold: Mild Ens at 240h and 360h (60:40 in favour of cold on the 06h GEFS) so slight trend to mild but no clear breakthrough to Atlantic yet being modeled.

After the 00Z GEFS trended milder, the 06Z trended back to cold and now the 12Z has gone milder again.

And still nothing hitting -10C: a testament to the pathetic lack of cold on this side of the pole this month.

sorry rob - my post earlier was incorrect re the gefs - they are still solidly neg AO throughout. eps and geps are heading back to neutral. I have found the gefs to be the best guidance re AO over the past month.  

Just to lift the spirits of those further south east the 12z WRF run shows some snow right down to Kent at one stage and widely north of London

Arpege for Sunday northern cut off point looks to be Yorkshire

Same model - predicted snow laying at noon on Sunday

Just checked the full run - brilliant for where we live if it verifies. Fingers crossed, but these situations can never be taken for granted until they happen - I won't feel secure about it until and unless I get up on Sunday morning and see the white stuff.

Fascinating - Arpege also hints at a brief "rain to snow" event down in this corner on Sunday. In both cases, it seems to be the intensity of the precipitation pulling down slightly colder air, lowering dewpoints such that snow is possible, albeit briefly. That WRF run really does have good resolution, as the frame before that chart (1 hour before) shows just the Downs seeing snow... you can see the effect the freezing level dropping a couple of hundred feet makes!

Truth be told, any snow falling on Sunday would be a complete bonus here, as I'm expecting cold rain only. It'll be interesting to see what Euro4 makes of it when Sunday creeps into range (tomorrow afternoon). Euro4 is, I believe, an offshoot of the high-res model used by the Met Office for short-term forecasts. I'd imagine it has the resolution to capture things such as that shown by Arpege/WRF, whereas I suspect the UM, or normal Met Office model, doesn't.

EDIT: And if by some fluke that heavy rain turns into heavy snow for a while, chaos will ensue on the roads. For the Midlands and north Wales, I'd imagine it'll be pretty dicey during the morning on Sunday!

Those are the 00z charts. 12z is available here

https://www.theweatheroutlook.com/twodata/arpege.aspx

GEFS seems to have more milder or less cold solutions in the run up to Xmas. It's not just background noise IMO. I'll be keeping an eye on that and checking the Met Office 30 dayer updates to see whether they are picking up the possibility of a change.   

Turns milder for a couple of days if the models are to be believed. Although whether it is cold enough to be wintry or not is a different matter.

Fingers crossed, even if it is only briefly white.

The Arpege run showed a similar effect of increased intensity of precipitation turning rain/sleet to snow - I noted it in an earlier post.

The main reason I showed the WRF run was to underline that nothing is remotely fixed yet. 100 miles either way at 60+ hours out is not surprising.  Generally you’d say sliders tend to be adjusted further west with time because of the effect of the cold air in place but this isn’t a simple slider.

Valid for 3PM, 11-12-17

A bit tiny - is that from the 12Z ECM?

The 96hr ECM chart looks interesting.

Yep, it's the 12z.

Latest fax for Sunday 12h.Occlusion has shifted very slightly south.

Tantalising for us southern folk. If I stand on a chair and look north I'll almost be able to see the snowfields of the fabled Arctic kingdom beyond the hallowed pathway known as M4 

That looks good for the SE contingent. Somewhere will get buried in Sunday.

Surely the ecm has been on the sherry with those depths.

240h seems to be a nomans land   tipping point for something -either more atlantic or a pressure build?

ECM 12z also looks to be flattening the pattern out. Remaining coldish at times but further signs of a possible change in the mid term?

https://www.theweatheroutlook.com/twodata/ecmwf.aspx?run=na&charthour=240&chartname=mslp500&chartregion=na-region&charttag=500hPa%20GPDM

Longer term term:  JMA 12z 192 - view from the pole: 850s A distinct cooling in the Arctic areas closer to us - a good sign IMHO for a decent cold shot at or soon after Christmas. A correctly placed Arctic High is what I will look for in the third and 4th weeks of the month.  Until then, its a few transient flakes as a reward for hours of diligent model watching. (if I'm lucky)

Without wanting to commit the WIO sin at this stage, based on the long-range forecasts of Jan/Feb being much milder than December there has to be quite a chance that the next week or so could be the wintriest we see... IF the hints of flattening towards Christmas come off.