Question, do all the models initialize with the same data? If this is the case then the ECM is likely to be bad, but the 0Z is likely to be a massive improvement. 

No. ECM initialises with the most, which is why it takes so long to come out!

OK I'm assuming UKMO does aswell then. What about GEM, JMA, NAVGEM, GFS, GFSP?

No, it's quite accurate for the date it was run.

Hi Darren,

the date says 22nd 12z - am I missing something? Have they published duff data then?

No, MetO initialises with less data than ECM AFAIK. As for the others, JMA aside they all start coming out at a similar time - so it's likely they have similar data input.

Look more closely at the date on the chart itself. Hint: you've picked a T+6 chart, but that's no longer listed as a valid option on the site...

I really don't envy the professionals at the moment.

For me, the UKMO looks the best of a bad lot so far, but rather than the T+144 screaming potential to me, I think if we were to go on 24 hours, it would collapse that high over the UK completely.

But as that is 168 hours away, and we can't even fathom out Boxing Day yet, it'll all change again on the next run.

Would just like to say, Gavin's video today is out of the top drawer as he tries to explain the charts.

That man is a real pro in my book, and he has made an incredibly complex situation easier to understand.

Hats off to you Gavin - your website is outstanding.

Another useless set of runs coming out I see, no consistency, no cross-model agreement, nothing 

Case in point as mentioned by others already: day four from GFSP (left) and UKMO (right)

Jet running straight NE from the Azores (GFSP) versus jet riding up and over a mid-Atlantic ridge (UKMO).

The outcomes are drastically different; GFSP fires the main low on east while a secondary low drops south, while UKMO drops the main low straight down to the Mediterranean.

The latter opens the door wide for a ridge to build from the UK to Scandinavia, with a decent cold feed from the east for day 6. The former has the UK low phasing with the Scandi trough and leaving us at the mercy of the Atlantic westerlies. The flattening of the pattern takes a while and is far from convincing on the GFSP run, but is much quicker and more asserted on what is a truly tragic GFS 12z run.

GEM tries to be more amplified than GFS and GFSP, but with the jet running straight NE on day 4, it has no means of generating an easterly, despite the Atlantic jet digging some way south days 7-10.

Good (from a cold weather perspective) to see a fair number of UKMO-like outcomes in the GEFS, and of course ECM was all for the dropping trough on its 00z op run, so once again we're left without any real indication as to which output is more likely to verify.

Taken on it's own, the GFS/GFSP trend toward a more northerly track to the main low this weekend, with greater east-west momentum (setting the crazy GFSP 06z aside) is concerning, but the huge level of uncertainty means it may just be a fluke. This may instead be true of the shift by UKMO from its 00z run (that mid-Atlantic ridge was absent on the 00z run hence the very different track). Or they could all be barking up their own wrong trees...

Nor do I!

I daresay you're underestimating the potential of the UKMO output there - with such a deep low over the Med. coupled with a separate low dug down to the Azores helping to turn the jet away from the SW-NE alignment that would trouble the high, that ridge has plenty of support for lasting a good number of days longer.

Shame it's only one of countless outcomes on offer at the moment because I'd be quite happy with it! 

Met O 144 NH view.  I think I've got my "cold tinted glasses" on as if there was a 168 chart I reckon we would could see a Scandi High there.  A terrible case of wishful thinking, probably

And some... based on T+126, 132 etc. V cold/wintry NE'ly undercut as the low centre transits SE.          

Comment from Ian F on NW   reference the UKMO

http://www.meteociel.fr/modeles/ecmwf/runs/2014122212/ECM1-144.GIF?22-0

http://www.meteociel.fr/modeles/ecmwf/runs/2014122212/ECM0-144.GIF?22-0

ECM not a million miles from UKMO now

http://www.meteociel.fr/ukmo/runs/2014122212/UW144-21.GIF?22-18

http://www.meteociel.fr/ukmo/runs/2014122212/UW144-7.GIF?22-18

UKMO a tad colder at the same stage

Dare I say there might be some interest in the SE ( see the comment from I F )

Unless it is in the 192hr+ range I can't see it. I guess at +144hrs with evaporative cooling there is a risk of wet snow for some for a time.

Edit: having now seen the 192hr chart I'd rather have the GFS 

Luckily he can

I'm confused. Your post on the previous page seems to refer to the UKO run not the ECMWF (to which I refer). I don't think the ECM 12 z was even available at the time of IF's comment?

post 316 on NW in model output thread, Ian was commenting on the 144 UKMO charts ,  as your were commenting on Ian's comment I naturally assumed you were referring to the UKMO  

The main action from an IMBY perspective would be on 28 possibly 29 December as the NEly follows the sinking low.  You are right, the ECM is pretty dull but I imagine the actuality will be slightly less uninteresting, and possibly wildly different, possibly something like the UKMO 144 which is close to a snow chart down here; though possibly a lot more mild.  FI is clearly at 120 hours presently. 

Hold those pens a new thread coming

Another quote from Ian Ferguson on Netweather.

Different organisations/companies provide forecast advice to different councils. The heads-up to them for next weekend is solely in precautionary (not prescriptive) response to some of the forecast solutions being chewed-over currently. 00z EC, for example, shifted goalposts with it's snow threat/distribution charts into that period, yielding a more bothersome signal down across Midlands into parts of the south, but it's all a moveable feast of course.