Who is looking North, I'm not

Coldest set of temps we have seen on a run for some time

From 6pm on 24th 7c , 6c , 7c , 3c , 2c , 3 c , 1c , 1c , 0c , 2c , 2c , 2c , 1c ,

Your comment of a MASSIVE step back for a cold spell is laughable Rob, sorry but I don't see how you can say that

This is said every year but you have to treat any high pressure modelling over Greenland region with a huge pinch of salt because if I remember the models they have trouble with modelling over the plateau region. Thats why it can show a 1045mb high in one frame and 18 hours it's gone. The computer has produced a phantom Greenland high. 

I think the GFS ends quite splendidly really.  Post the Storm on the 27th, we enter a very long cold spell that carries til the end of the run.  No sign of Mild SWerlys.  Or they arre, they dont really impact the UK.  Take a look at the euro temps at the end of the run!

All in all 

Days 1-5 - Dominated by HP to the south, wet and mild.

Days 6-10 - Dominated by northerly winds, stormy - detail to be decided on who gets cold air and when

Days 10-14 - Dominated by Winds from the east, becoming drier very cold wind, snow flurries just about anywhere.

The latter could end up anywhere, and just because it looks rather flat and dry, doesnt mean it will end up being so.  If the GFS is keen on a Scandi block - that could develop a number of characteristics with time....Interestingly the GFS ends up placing that deep Boxing day LP out over Italy, which if this develops into a proper Eastlery (currently trending) - I could see favour of this LP to start moving back west and  feed back to the atlantic via the UK and France.

Agree that the Eastern Block looks like being squeezed away.However in the absence of northern blocking the development of a Scandi HP looks best bet for proper cold spell.The Atlantic option is  changeable with cold snaps with NW/N followed by collapsing ridges.

As it represents the current middle-ground solution, with UKMO in close support, here's a closer look at the GFSP 06z's storm event:

This version of the charts best shows the sort of trouble that a particularly deep low could bring in terms of precipitation type; because there looks to be such deep cold to our NW as the storm develops, a strong one will pull a tongue of that in towards the low pressure center. This could bring a period of heavy snowfall given that with high precipitation rates and low pressure bringing the 850hPa level a bit closer to the surface, uppers not far below zero could be sufficient (let alone as low as -6*C as shown above). It depends on to what extent the strong winds counter the evaporative cooling effect (as snow melts, it takes in energy from the surrounding air and cools it).

This run then brings the warmer core of the low down across the areas that saw this tongue of cold air, bringing some spells of rain... so it's heavy back-end frontal snow followed by a bit of rain to make a mess of things - exciting to watch if the snow falls in the middle of the day (particularly given 40 mph wind gusts) as shown on this particular outcome, but no lasting snow on the ground.

The strongest winds are associated with the warmer core, and they look destructive:

Tree-troubling gusts there. The swathe of near-70 mph gusts then crosses the south during the following few hours.

What really heightens concern is that this type of intense storm formation, with a distinct 'conveyor' of warmer air curling into the low and meeting a cold tongue of air wrapping in to meet it, is the sort of setup that can produce a sting jet.

At this stage, adjustments in the storm track could change the game entirely, and really the above represents the most extreme outcome on offer from the op runs so far today.

The normal GFS shows an alternative in which the shortwave from the SW tracks further south and doesn't phase soon enough to produce such a system - we still get an intense low but it lacks the structure needed for a sting jet event. It also avoids bringing a second round of less cold air through the UK, so it's a relatively simple rain to snow transition, though with hardly any of the latter across England and Wales. All in all, a far less extreme outcome, though,  still with a swathe of damaging winds to worry about, so still a severe weather event.

Due to ECM still having the low further NW than GFSP and UKMO, and the sheer extremity of the middle-ground outcomes, there's not really anything to justify calling any one solution as the most likely at this point in time... more runs needed!

In other news, GFSP is now being a big tease with the idea of a Scandi High arising in response to low heights reaching the Med. and the upstream pattern retaining enough amplification. We can never catch a break from these distant offerings can we? 

This can only start to be taken with less than a truckload of salt if and when ECM treats the above storm system in the same sort of way as GFSP, UKMO and GFS.

Extended 0z EPS - still no real change, still showing a cold spell as the most likely outcome:

Are those 2m temps?

They must be 2mTs surely? Plenty of ECM runs get London down to -8C for periods at 850 and non of those go below -5.
The lack of diurnal variation is likely due to a cloudy HP at the lower end - and the scatter confuses the brain that's for sure.

If so, unless I'm reading them wrong (probably) the average is around +3 or so, and barely a single run touches -5 at any stage?

Yup!

Problem solved. They ARE 2m temps. Cheers Darren. 

Remember people we do have two opportunities, as in any case like this, to maintain our cold spell.

The first ofc is a reload from the NW that prevents toppling and gives us a new leash of cold air.

But we also have an opportunity even if the high does collapse. When the winds become southerly it is quite possible for a 'turn over' to occur and for us to go back into the freezer, as some of the models are suggesting with height rises over scandanavia.

Basically it is not over until the winds have a westerly component in them, southerly winds are your friend, not your enemy.

Also bear in mind, the high cannot collapse so long as heights remain low to our east, and this ofc depends on our trough, and it is being modelled differently on every single run.

Summary GEFS.

144h 80% ENS support deep depression close to UK.Exact track /depth will be refined no doubt.

240h 60% of ENS have HP to SW with flow West or SW.40% have HP to W/ Mid Atalantic with more NW/N flow.No support for HP build to East

360h 80% Strong westerly flow with remaining  20% SW or NW.Atlantic very much in charge with no sign of eastern HP block 

A lot of rose tinted spectacle wearers around at present but realistically there are not many hints that we are going to see any spectacular wintry charts in the next few weeks.

The caveat is this potential storm may be skewing things a lot and I think we may be in a better place to judge once this week coming is out of the way.

But to hope vainly for the prospect of an Easterly at present is just that.  Hope. There is more interest than last winter but that doesn't mean the conditions we will see will be any more interesting from a winter perspective. 

Ironically if the storm verifies it will be arguably worse than anything we saw during last "winter" - the winter that never was.

OK I should have said cold and snowy spell. Those low temps are just gloomy HP so not too exciting!

However there may be at least something interesting next weekend with a decent winter gale and perhaps some transient heavy snow even in the south :)

Where?

Here is generally much more sanguine and hence why I never joined over at NW.

Yes but you are from snowless Witney , you lot are all doom and gloom merchants

Fair comment Rob