thanks storm-chaser.as always your posts are very detailed  and informative at least this winter has something to offer unlike last winter that thru us a few red herrings and teased us with cold potential.

Great to see Retron is back/still about. Darren I always enjoyed your analysis and posts and really appreciated them. Hope to see more from you this winter, including cheeky updates from when you are at work at the wolf centre!

To go back on topic, I like the idea of potential developments to the NE, in time for Xmas would be just right......time will tell 😉

Retron's returned!!!!!!

***FAINTS***

First tentative whiff of height rises over/near Greenland in EC 12z clusters beyond circa 21 Dec (and out to T+360) with resultant hints of possible northerly flow regime for UK. Baby-steps....We expect there to be a possible lag period before this sort of outcome emerges further in EC with any stronger definition, but still too far off to warrant anything 'excitable' by way of forum reaction, I stress

From Fergie on the other side

At last there's a GFSP op run which not only handles things very much like ECM out to day 10 but avoids powering energy NE beyond day 10!

So here we go, the GFSP 18z op run day 10 on the left, day 14 on the right:

Notice how that nose of low heights going SE from the UK on day 10, this being less pronounced than on the ECM 12z op run, develops into something far more substantial that starts to undercut the Siberian High. Fair to imagine that the ECM run would have had a good go at it too, though it's not so clear on that run whether the low south of Greenland would track SE as smartly as it does on the GFSP 18z op.

Then, thanks to the absence of low pressure powering up in the western North Atlantic (which the 18z GFS really runs away with), this process is able to continue on to day 16 with no sign of stopping there.

It ends up giving a very nice illustration as to how the Siberian High can venture towards the Arctic:

Check out the low heights on their way to cutting off that area of higher heights which itself is nosing towards the pole. Meanwhile pressure is steadily rising across a large swathe of the Arctic as the low heights finally displace further into the mid-latitudes.

This is all well outside the reliable, but does a great job of outlining the sort of developments that MOGREPS and the EC Ensembles may be starting to explore... an element of guesswork in there of course as those model outputs remain behind closed doors. I might get to change that one day soon but of course I won't be allowed to start handing out freebies 

I think one thing is for certain, there is no sign of mild weather. We are in a period of cold zonality, it will be interesting to see if December can manage a below average CET while simultaneously being a more mobile than average year. That would be impressive and highly unusual, although I don't think TWOians would be all that pleased about it!

Until all that, I am expressing some concern regarding Thursday night/Friday morning with the chance of a sharp secondary low pressure feature zipping eastwards along the southern half of the UK.
  However, each model have their own solutions ranging from a "St Judes"-type bombing low (closed circulation) to nothing more than a weakening wave-like feature so I think it's going to be one of those "I won't know for sure until it's a few hours away" situation.

HERE IS MY LATEST ANALYSIS FROM THE OUTPUTS OF THE WEATHER COMPUTER PREDICTION MODELS FOR TWO WEEKS FROM 8AM TODAY TUESDAY DECEMBER 9TH 2014.

NEXT UPDATE WEDNESDAY DECEMBER 10TH 08:00

THE CURRENT GENERAL SITUATION An intense depression close to Iceland tonight will move slowly East driving an active cold front SE across the UK today and tonight with storm force Westerly gales across Northern areas tomorrow.

MODELS-2 WEEK HEADLINE Rather cold and windy for most with wintry showers or longer spells of rain or sleet with snow on hills especially in the North later this week. Perhaps milder especially in the South next week. Some night frosts where skies clear.

THE JET STREAM ENSEMBLE FORECAST The Jet Stream Ensemble forecast shows the strong flow continuing to the South of the UK under a deep trough over the next few days gradually moving North and weakening somewhat next week with a mix of solutions shown but still with a bias for the flow to travel West to East in the vicinity of the UK between lower pressure to the North of the UK and High to the South.

GFS OPERATIONAL The GFS operational this morning shows a continuation in the very changeable and often windy pattern of weather with a continuation of Low pressure areas driving East close to Northern Scotland with spells of rain followed by showers and sunny intervals with the showers wintry on hills at times. Little change to this pattern is shown right through to the end of the run taking us up to the run up to Christmas 2014.

THE GFS PARALLEL RUN The GFS Parallel run is much the same as the operational with only day to day differences shown between the changeable and Westerly theme which continues through to the end of the run. All areas would see spells of rain and average temperatures and spells of chillier conditions with wintry showers in the North and patchy frosts on occasions between weather systems.

THE GFS CONTROL The GFS control run also shows a similar pattern to the operational above but shows a more defined pull of milder tropical maritime air across the UK in conjunction with higher pressure over France through week 2 with less rainfall likely too especially over the South.

THE GEFS ENSEMBLES The GEFS Ensembles are indicative that Low pressure to the North of the UK and High to the South and SW will be the dominant pattern over the whole period. There will be a period through the start of the second week when High pressure comes close to Southern Britain for a time lessening the effects of wind and rain to a spell of milder weather before the return of polar maritime air at times brings back more volatile conditions with rain or showers at times as we approach Christmas.

UKMO UKMO today shows milder air returning from the West later in the weekend as the North flow early in the weekend backs Westerly. There will be spells of rain followed by showers at the start of next week with any wintry showers more confined to Scottish high ground by then.

THE FAX CHARTS The Fax Charts show a cold front sweeping SE tonight followed by a cold and very strong Westerly flow with showers tomorrow and Thursday. A secondary depression then is shown to deepen and move quickly NE across England Thursday night with rain and strong winds clearing to lighter NW winds and wintry showers at the weekend with milder westerly air over the Atlantic poised to approach the UK at the start of next week.

GEM GEM this morning maintains the basic pattern of Low pressure to the North and High to the SW over it's run this morning. This means a continuation of spells of wind and rain and average temperatures will be mixed with periods of sunshine and showers, wintry at times over the North. Patchy frost is likely in the quieter periods between weather systems.

NAVGEM NAVGEM this morning shows windy weather continuing for the whole of the run with further Low pressure areas crossing a point to the North of Scotland at various occasions over the week, each bringing a spell of rain and followed by clearer and colder weather with sunshine and showers, wintry on the hills.

ECM ECM this morning shows a very mobile pattern with strong Low pressure areas crossing East to the North of Scotland with strong winds and rain affecting all areas at times alternating with clearer and colder conditions with sunshine and showers in blustery WNW winds. Late in the run a flatter westerly flow develops which if transpired would bring milder and cloudy weather to many with rain more restricted towards the North and West in tropical maritime air for a time..

ECM ENSEMBLES This morning's Ensemble data remains largely unchanged with the overriding factor likely to be one of Low pressure situated to the North of the UK and High pressure to the SW. There will be spells ofstrong winds, rain and showers likely across all areas interspersed with colder and more showery spells with snowfall on Northern hills at times. Overall temperatures will be in the range of near or slightly below normal at times over the North and near to or slightly above average at times in the South but windchill will be a notable factor at times.

NOTABLE TREND CHANGES FROM PREVIOUS RUNS Not any major shift in trend this morning with no cross model or high percentage chance of anything majorly cold affecting the UK in the run up to Christmas shown by any output this morning.

MY THOUGHTS  The volatile pattern of strong Westerly winds and occasional periods of rain and wintry showers look likely to be maintained across the UK in the next week or two. Despite some indications from good sources to the contrary of what the current model output available to the general public shows there remains little indication of anything other than changeable weather with some strong winds at times accompanying the heady mix of rain and wintry showers. It remains unlikely than the South will see anything other than the odd flake in the showery periods whereas the high ground of the North could see copious amounts of snow at times. Looking longer term there seems little sign of anything exciting affecting the UK in the run up to Chrsistmas with broadly Westerly winds maintained. It maybe in fact thet a flatter pattern for a time brings a milder and less wet period in part of week 2 before the undulating pattern between mild and cold periods return late in the period but there still seems a lot of work to be dome in the atmosphere if we are going to see a major shift towards universally UK wide cold and wintry weather this side of the New year. Of course we must always be mindful that we are not privvy to data that some of our powers at Exeter see so what I've described above is only indicative of what we can see and doesn't cater for hinted differences to the pattern that the Met boys see so we will have to see whether any differences manifest or transpire across the mainstream model outputs in the coming days.

All JUST FOR FUN, of course, but you'd have to be a right Scrooge and/or militant mildie not to behold this with comfort and joy:

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=384&mode=0

528 decameter line somewhere over Biscay and the Dordogne

Bah, and if I may add, Humbug.  

Of course if it actually turns out like that, I'll eat my Father Christmas hat!!

I reckon that the current pattern would have generated more by way of interest among people here had it been in any December prior to 2009 & 2010. The events of both of those Decembers do seem to have raised many people's expectations of wintry weather in December, unrealistically perhaps.

That seems to be at odds with some of the comments from yesterday. Have they backed away from a more blocked picture?

Best to have a packet of sage and onion ready, just in case. Much the same chart happened 10 years ago to the very hour:

http://www.meteociel.fr/modeles/archives/archives.php?day=25&month=12&year=2004&hour=0&map=1&mode=0

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=384&mode=0

6z GFS is running but the GFSP is currently MIA.

I only have access to the regular ensemble postage stamps for ECM and MOGREPS and they were both showing the same general pattern yesterday. I can only guess that the suggestions about a change of pattern comes from output beyond T+360 something I can't see.

Worth adding that most members do show brief NW or N cold air outbreaks several times during the period.

Bank this whilst it lasts: - Christmas day everyone!! - Winds coming all the way down from Iceland!!

Please forgive my ignorance Brian, but what does MIA mean?

 PS: It's an upstream problem so won't be on other sites at the moment either.