If it has support, that has to be a positive sign IMO.

Just running through the GEFS individual runs right now Brian, Im not sure why they arent exciting.  I count 14/5 out of 20  going for Pressure rise to our north or west at some point around 216 hrs.  With the runs either already in the depths of cold or on the verge of introducing cold.

Call me an optimist, but i reckon thats one of the best GEFS runs weve had in years.

Looking at the GEFS from 216 hrs onwards:

P1 - Greenland HP 

P2 - Tranisitional Northern HP 

P3 - Weak Greenland HP

P4 - Tranisitional Northern HP 

P5 - Moderate Greenland HP 

P6 - Weak Greenland HP -> Azores HP 

P7 - Tranisitional Northern HP 

P8 - Azores / Mild SW 

P9 - UK HP -> Scandi HP (almost)

P10 - UK HP -> Northern UK HP 

P11 - Weak Greenland HP -> Mild SW

P12 -  Weak Greenland HP -> Mild SW

P13 - Mild SW

P14 - Greenland HP 

P15 - Greenland HP -> Northern based HP 

P16- Greenland HP -> UK HP  

P17 - Azores / Mild SW 

P18 - Atlantic mobile HP

P19 - Greenland HP -> UK HP  

P20 - Greenland HP  

The period between xmas and new year, whilst still a long way off, is starting to look interesting if you like stormy weather.

The shorter term zonal variability and meandering polar front will be largely a continuation of what we have now.

At this stage I do not see any longer term reduction in Atlantic power BUT the fact that there a few more colder options in the ensembles suggests that the jet may be sinking south which would bring greater cold risk to more places.

2/1 the field (Aberdeen, Glasgow, Edinburgh) with William Hill.

Sorry, totally OT, I'll go back to lurking again

Fingers crossed the current encouraging signs continue though.....

Trend seems to be firming up for a little depression to head south over the country over Christmas Eve and into Christmas morning. Hills in the north could well turn white briefly from this: http://www.wetterzentrale.de/pics/Rtavn1921.gif

A quick return to dross on the 06Z though with the purples rapidly regrouping over Greenland. Not much sign of the vortex being disrupted here. http://www.wetterzentrale.de/pics/Rtavn2881.gif

Albert's post is rather misleading. Here's the actual Fergie comment:

"Next updated assessment due later this morning. Last one discussed colder/unsettled/windier possibilities, and they've leaned last couple of days towards high to W, low to E; more veered flow, so broad theme in keeping with 00z output. However, very unwise to over-react to couple of GFSruns at such a range; public f'cast message of anything so pronounced will need much more coherence showing nearer the time in EC & MOGREPS EPS."

Firstly, their broad pattern idea certainly means the 00z output is within what they consider to be possible (i.e. the ingredients are there) but they have decided that, as we so often say on this thread, more runs are needed before any significant changes to expectations can be made.

Now then, I hope you folks have your reading glasses on because I have written an account of the way GFSP, ECM and GFS have developed their operational output since last weekend, for documentary purposes - read if you're interested or ignore if you don't fancy it :

NWP Modelling 14th-17th December 2014

As a amplified Pacific/U.S. pattern (negative East Pacific Oscilliation or EPO) gained ground in the models, model response varied.

Amplifcation of the mid-Atlantic ridge featured in most runs 14th-15th but mobility remained an issue with GFSP bringing only transient cold with the help of a Scandi trough before a strong push of low heights leaving Canada that flattened the ridge on most runs.

ECM stayed away from any signs of such flattening, but showed little consistency with how the U.S. trough interacted with the mid-Atlantic ridge; runs swung between the trough undercutting the ridge and the trough providing good warm air advection (WAA) to help build the ridge toward Greenland. The former option led to signs of a west-based -ve NAO being shown.

GFS was very keen on a Greenland High even at this early stage, but the jet going underneath was too strong on most runs, and the Scandi High not digging far south enough on others, to place the UK on the cold side of developing low pressure. Very similar behaviour occured prior to the prolonged cold period of Nov/Dec 2010.

16th saw marked changes in GFSP with blocking to the NW gaining prominence, and unlike GFS the jet underneath was shown to be weak enough and far enough south to place the UK on the cold side of some of the storm systems. The trend of the day was to shift the storm track still further south with an increasing signal for a complex trough developing over NW Europe.

ECM again flipped between an amplifying (driving WAA) U.S. trough and an undercutting one, the former looking 'safer' going forward for significant final-week cold in 2014. Consistent, though, was the jet being shown to track a long way south, similar to GFSP's output.

GFS persisted with the jet being too far north on the 00z and 06z runs but the 12z had a much weaker influence of Atlantic LP out to day 10 with a shallow Channel low. A push NE later in FI was followed by LP digging into Europe and renewed Atlantic/Europe pattern amplification.

The 17th has basically taken things to the next level, with a strong Greenland High quite suddenly in place on both the GFSP and ECM 00z runs. The consequence is deceptively simple on the broad scale; the jet is even further south and supressed in intensity, meaning lows track more towards Europe from the Atlantic and take until they're about to reach the UK to really start developing.

GFSP really digs LP down into Europe just as the HP over Greenland begins to subside. This really helps sustain a tall mid-Atlantic ridge while pulling in more and more cold air into a complex unsettled pattern across the UK giving snow event after snow event.
Amazingly enough, GFS is very similar, despite the recent reluctance of the GEFS to have the jet tracking so far south. Those ensembles showed little movement 14th-17th until a shift colder this morning.

ECM offers strong support for the GFS and GFSP solutions going forward from day 10, with strong HP to the NW. However before that time the angle of the mid-Atlantic ridge is not as favourable for cold air reaching the UK so conditions aren't as wintry for Christmas Day itself.

I have also read that the ECM ensembles are promising this morning, which suggests that MOGREPS aren't really going for the strong high to the NW and/or NW Europe low at this point in time, or at least continue to Show a huge spread of options with no real dominant outcome.

The GFS para is stunning once again a snowfest!

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=276&mode=0&runpara=1

A thing of beauty.  Classic battleground snow for the south.

Entire eastern side of the country getting a snow fest if this chart verified:

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=300&mode=2&runpara=1

I wonder how much support there will be for this outcome in the ensemble (he said, knowing it's going to be a MASSIVE cold outlier)

Spoilsport..... Your are almost certainly correct however.....

Interesting that while both GFS and GFSP pick up on some 'shortwave drama' on day 8 which interferes with the mid-Atlantic ridge, GFSP not only maintains the low digging into NW Europe but has it happening more quickly. This results in a Scandi High being born days 10-11 and another epic final 5 days of the run as a decent easterly is followed by battleground scenarios with no sign of collapsing as of day 16.

By contrast GFS has the subtropical jet pushing the ridge west of Iberia into Europe just a bit too fast for that digging trough to take place. Really the LP could still easily have slid SE from day 10  (there's already an Italy low in place!) but instead the subtropical jet then powers LP across the Atlantic and it all flattens out. Typical GFS bias? Probably but can't be sure of course.

Come to think of it, that low pressure in Italy, also present on the GFSP 00z and 06z op runs days 9-10, and the GFS 00z, represents a huge change from just a couple of days ago, when a strong ridge was being shown to persist across much of Europe and the Med.

A good pal of mine said to me back then how the anomalous warmth down there ought to lead to low pressure development and it looks like he was right on the money! I do wish he would post on here (hint hint,  I know you're reading this!).

surely Xmas Day was always a marginal outcome for snow in most places.  the potential is afterwards, and the ensemble hasn't got there yet.

It was never in the equation away higher northern and western areas. Look at the bigger picture emerging here.

There was a pretty big jump cold on the 00z GEFS in the 10-16 day range (well outside the reliable of course!) which does make the 06z seem a bit of a letdown really. Glad the parallel provided a good balance 

Met Office suggest low support for ECM's vicious Boxing Day Blowout and also the severity of the longer-range output from the last two GFSP runs and the GFSP 00z op.

None of this is at all unexpected and while the overall cold trend is the best I've seen in almost two years, I have seen that spoiled by uncooperative shortwave lows too many times in the past to allow more than short-lived excitement - that happening as I watch the more sensational runs unfold, which is very entertaining especially after months of nothing more than fleeting suggestions of something better.

Someone take me out of my confused state

It does seem ( me included ) we pick a GFS run that suits our need , so which are we to really take note of

GFS or GFSP ??? , and just why can they be so different

Thanking you

F

Apologies - I agree. 

From looking at the GFS theres the potential for flooding in Northwest England Sunday night onwards - potentially Cumbria.  Seems a front stall for several days and meandre ever so slightly north and south.  These were the same conditions that brought carnage to Cockermouth back in 2009

Sunday night: Front arrives into Northwest England

Front still hovering around Northwest England 40 hrs later:

Interestingly embedded within this time another shortwave LP comes through aswell increasing rainfall amounts.