The models are clearly picking up a disturbance in the force for the 3rd week of Jan with a great variety of solutions being shown, compared to the zonal consensus at the same time frame a few days ago. So you could say we're entering a lottery for that time period - what odds that we will hit the jackpot?

Looking at the individual perturbations the most common scenario is basically a toppler.

This I think a fair representation of the most common scenario and the means so is a good bet at this stage I think

NAEFS anomalies

It must be said the NAEFS and GEM ens have been consistently less amplified than the GEFS. So it'll be interesting to see how this goes

Aside from cold there are some very nasty storms popping up in the carts. The GFS delivers a vicious storm to Scotland next week

GFS control, yikes

And this from P1 and P2. Many other nasty perturbations, worth keeping an eye on.

Some jet heading our way

Jako's  comment is aimed and constant wind and rain and higher temps

Only just got online today, and my initial impression is that GFS and GFSP have displayed typical behaviour, showing a strong reaction to a new signal (the MJO being taken to phase 7 by the GEFS), then backing down in light of uncertainty regarding that signal, with a variety of outcomes starting to appear instead of the insistence on strong height rises to our NW.

No MJO model updates to work with so far today so I can only imagine that we still have a good signal for it to reach stage 6 but continued high uncertainty for phase 7.

http://www.americanwx.com/raleighwx/MJO/MJO/JanENMJOphase6all500mb.gif

http://www.americanwx.com/raleighwx/MJO/MJO/JanENMJOphase7all500mb.gif

It remains easy to see how a phase 6 to 7 transition would encourage the pattern across the UK to evolve, with the mean trough sinking into Europe. Couple that with a weak but still influential polar vortex and the toppler scenarios portrayed by the 06z GFS and GFSP op runs seem like a good illustration of the probable route.

We can also see how a decay in phase 6 would encourage the high pressure over Europe to hold on and leave us stuck in a continuation of the westerlies. The ECM 00z was an unwelcome insight into how that could play out, while the 00z GFS and GFSP runs seemed to be caught between two minds.

It would not be surprising to find that the ECM ensembles continue to be the least keen on taking the MJO on to phase 7, as this was the case last time we had this situation. As I said yesterday, the MJO did manage to push on into phase 7 that time, but it was only at very low amplitude which meant there was hardly any influence on the pattern sequence we went through.

Looking back through a series of snapshots that I took when investigating the modelling of the MJO in December, it turns out that outcome was actually a halfway house between what the GEFS and the ECM ensembles went for when it was in the 8-10 day range.

A repeat performance would again see a small phase 7 influence with a temporary decline in high pressure across Europe in favour of a mid-Atlantic ridge. I suppose the 00z GFS and GFSP runs were actually quite close to this, not very inspiring but the most realistic view that I can come up with at this point in time.

there is every chance they are related

Meanwhile GFS gives us another variation

12z GFS & GFSP don't really cut the mustard for me today. The GFS op is obviously the more interesting run for coldies.

(GFS will be replaced on 14/01 by the GFSP).

http://www.theweatheroutlook.com/twodata/datmdlout.aspx

I am sure Mr Brown would be delighted Marcus...

In response to White Meadows post earlier, at least I don't sit on the fence and follow the co census of opinion. Please do enlighten us with your take on the situation, if indeed you can 

;-)

Tidied.

12z GFS and GFSP are both remarkably consistent at 312 hours in promoting a mid atlantic ridge that would usher in a generally colder polar maritime incursion.

The background signal is fairly strong for this to occur in the 17-19th January period.

The ECM ensemble clusters that Darren helpfully posted indicate a similar set up.

My gut feeling (and that is all it possibly can be at such range) is that this will be a brief NW'ly spell before the jet rolls back over the top. However as a Kent Winter Coldie myself I am very aware that such a set up can lead to a 2 or 3 day NE'ly convective snow fest before the whole thing collapses.

We are in a better position than 3 or 4 days ago..that's for sure. 

damn predictive text!

cheers David. 

ENS watch starts then.....

Back to the real world, the NAO looks on course to dip in about a weeks time. One would hope this co-incides with the warm 850's over Greenland in discussion yesterday.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/new.nao_index_ensm.html

them model charts above seem to look OTT to me, at this range,!!!  if this came of I would say luvvly  jubbly  rodders but would not surprise me that another red herring is about to occur, as always,  we shall see, !!!!

I am sure I have seen this highlighted elsewhere?

Interesting times for the GFS FI  most runs now ending with stubborn cold over europe forcing the jet to split and milder air south.

What strikes me as most interesting the moment, is how similar to the pattern in 2012/13 the current run ends.  This of course was a winter brought on (i believe) by a SSW.  It also didnt have a beast from the east type look to it, instead it always had just enough cold in it to force weather systems south and introduce lots of snow for some parts.  Whilst never really looking like a beast of a high pressure. its was more of a lazy block.

Now, im not really following the SSW chatter as its a little above my head, and confusing - as in one breath theres talks as if its already happened, about to happen or will happen in two weeks.  

What i do know is 2012/13 went on to have a great Jan, Feb and especially March.  Based on the current FI charts - could we be on for a repeat?

P3 on GFS is definitely a keeper - The Day After Tomorrow spring to mind looking at that one. If we don't get blown away or drowned in storm surges we'll be buried in snow by the 20th Jan. Fingers and toes crossed everyone! 

GEFS12z showing the cooling trend and then quite an uncertain picture by the end.

http://www.theweatheroutlook.com/twodata/datmdlout.aspx

Another GFS FI run toying with some sort of Atlantic ridge, although still a fair few ens members with much more southerly based HP.

Still it's a continuation of a reasonably strong signal for something a bit colder for a few days - be interesting to see if this signal gets stronger over the next few days and whether it firms up as a toppling ridge or something a bit more interesting.

In the near term milder and cooler interludes, with the worst of the wind and rain towards the North West. Down in my neck of the woods there's more in the way of HP influence so hopefully drier.

There's also still a few nasty little LPs shown to move over or near the UK, with the HP to the South presumably aiding a squeeze in the isobars.

Anybody remember January 2005? First half was zonal and very mild, second half was colder, but also a let-down with the "failed easterly" fiasco of the final week.

Looking at some of the output today I wonder if we could be in for something similar...

Nothing has changed that I can see (no noticeable upgrades or downgrades), its only a couple of days now before this comes into the high res frame, then the mood in here will go distinctly bipolar with eye candy and guff both on offer.

This chart perfectly illustrates the problem that it will need 'a lot' to overcome - the temperature gradient off the eastern seaboard is staggering (26 degrees within about 500 miles) and is a recipe for cyclogenesis:

http://www.meteociel.fr/modeles/cfse_cartes.php?ech=1254&mode=0&carte=1&run=3

For general amusement verging on jaw dropping amazement, browse through this run from the final week of February through to April. Everything from scandis to greenies to Icelandic highs to channel lows. The dream run!

Indeed. This is the main reason why next week is likely to be stormier and more volatile. The insane cold at T+120 in New York at 40N will have an influence at circa 192-240hrs on the UK given the zonal nature of the jet.

Caution is required..without a prolonged signal for an amplified jet we are at the mercy of the atlantic.