It's my wife's birthday today, and she can be a bit changeable as well

Up and running again........

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.

Given that FI is at around 120, and that the trend from the Euros has been to move from a flat pattern post Xmas to a sinking high  today, the most optimistic thing I can say is that maybe, just maybe the trend will be to get higher heights to stick further N, the Met O 120 has a lot to offer in this respect, a better 144 chart with blocking started further N could have been possible from the 120 point, hence Ian F tweeting earlier.

All to play for.

Ian Fergusons comments are easily the best news on a mediocre day from the models. Still very unclear what will happen after Christmas.

Uninspiring set of Op runs this evening.

GEFS is trending the wrong way.

Has the rollercoaster reached the end of the track? Time to get out and be 

 I wish her Happy Birthday

On to the models and  yeah, they're as changeable as ever except, as it happens, for the ECM op which is not far from its 00z effort.

It almost manages to replicate UKMO's 12z output, but the low is deeper and that seems to tie in with more of a desire to head east, which then conflicts with the SE motion of the storm, resulting in the system splitting in two, the main part dropping south while a small shortwave low flies off to the east. Unfortunately this leaves us without much of a low heading down to the Med. and also interferes with height rises over Scandinavia.

Thanks to the polar vortex lobe over Canada being well below full strength, it's still enough to develop a strong mid-latitude block centered just east of the UK, with a continental flow, so increasingly cold - but with no snow to be had. 

It does look a bit like one of those 'slow burners' where you're just waiting around for the Atlantic jet to permit an undercutting low. With the strat vortex looking increasingly troubled during the next 10 days the polar vortex may have a hard time holding together so it wouldn't be the worst position to be in 10 days from now... I'd still take the UKMO in a heartbeat though  but it does look like the best case scenario and such clean movement of low pressure tends to be hard to come by.

Overall, very snooze-inducing output if you're able to avoid being led by any individual output.

...although having just said that, GEFS aren't bad really:

Now this is a little misleading when comparing with the output of previous days, because the 00z and 12z suites have shown nearly all runs hitting -5*C for 25th/26th December when previously they were largely bottoming out close to -4*C, so some 15 'runs to -5*C' have appeared in the shorter range.

So really, today's longer-range output hasn't been as cold as yesterday's, but despite the trend in the op runs, there are more colder options in the 12z suite than the 00z set had to offer.

I suspect, though, that few of these feature more than slight occurrences of snowfall for most of the UK.

I'm seeing signs of a Bartlett on some of the runs this evening with the cold shunted down to the Balkans. I'll quickly add I've been driving for most of the day and haven't looked at things in much depth, especially the shorter term outlook for this weekend. 

There are a few, but no more than you might expect in a wide scatter of options.

I think the ECM is being understated in terms of attempting to maintain heights towards Scandinavia next week, although the way it fills the low as it drops across the UK goes against recent output which has more or less unanimously deepened the feature as it exited the UK.
If ever there was a case of saving a five day chart and overlaying on the corresponding zero hour synoptics in five days time for each model this is it.
Infact, I'm going to do it for the projected and actual synoptics for 00Z Sun 27th, saving the charts from the main output produced at 00Z tonight.
It will make jot all difference in what we get, but it will keep me occupied LOL

it all depends on the behaviour of the upstream trough and the track the next depression exits n america on. there are still loads of unknowns to our west and this leads to a pretty endless array of plausible outcomes. jet might split and undercut the atlantic ridge. or the opposite. or maybe a mixture. or maybe not. just a crazy period of modelling. safest bet is to predict a mid lat high and fairly cool surface conditions for much of the uk. more mobile further north and therefore less chilly. the models appear to want to bring a strong zonal flow courtesy of the return of the vortex aster to hudsons and a push sw into the atlantic from there.  guess a strong jet could provide more fun and games if it decides to dig south a bit or even split ahead of the uk. is it time for the strat to begin to influence the trop for a change this season and the weakening zonal flow high up to affect the trop jet, causing it to split to our west when one might expect it to do so to our east ?????

Ahhh.... yes. The 850's aren't a good guide (always use with caution anyway in this sort of winter set-up). EC 12z offers anywhere from 2-10cm snow from Cotswolds down across into central-southern England / northern Home Counties. MOGREPS, meanwhile, focuses further to E/SE and across NW as colder 'dig' focuses around W/NW flank. But none of this trustworthy, of course, given noticeably broad EPS spread at this range on how the evolution takes shape. Variance in track/depth/phasing quite stark in latest postage stamps, some (minority) even taking the low centre to exit from SW England!  Winds, however, a wider issue, whether in north, south or east. Still a way to go in resolving this one and history teaches us that potential explosive cyclogenesis may not resolve confidently (re track, depth and regionalised impacts) until short lead time. I'm not expecting this one to be much different (as model flux at present amply shows), so no point getting exercised about it for a while yet!

From IF on NW

The EPS are terrible, I'm hoping the 12Z are a dud because they have been nothing short of a disaster. 

Very good news for the South. Some sort of snow event has been in the models for some time now for the 27th/28th.

I suppose it wouldn't take much of an increase in the strength and/or persistence of the East Pacific ridge, or the transient high over Greenland, to have a significant impact on the Atlantic progression from this weekend onward.

At the moment it seems like just about anything is possible.

For the time being, interesting comments by Ian Ferguson that reveal the ECM event to have been a snow-bringer after all, which shows how the upper air temperatures aren't always a good enough guide, as they were in the -2 to -4*C range:

"EC 12z offers anywhere from 2-10cm snow from Cotswolds down across into central-southern England / northern Home Counties. MOGREPS, meanwhile, focuses further to E/SE and across NW as colder 'dig' focuses around W/NW flank. But none of this trustworthy, of course, given noticeably broad EPS spread at this range on how the evolution takes shape. Variance in track/depth/phasing quite stark in latest postage stamps, some even taken the low centre to exit from SW England!  Winds, however, a wider issue, whether in north, south or east. Still a way to go in resolving this one and history teaches us that potential explosive cyclogenesis may not resolve confidently (re track, depth and regionalised impacts) until short lead time. I'm not expecting this one to be much different (as model flux at present amply shows), so no point getting exercised about it for a while yet!"

Still the kitchen sink in evidence, with the storm track, timing and depth remaining about as clear as a pint of Guinness.

Edit: I see you beat me to the Fergie quote Gooner. Still, worth putting forward twice I feel 

Disappointing probably a better choice of word.

Disaster was in Glasgow

We are talking about the weather

http://www.meteociel.fr/ukmo/runs/2014122212/UN120-21.GIF?22-18

UKMO

http://modeles.meteociel.fr/modeles/gfs/runs/2014122218/gfsnh-0-120.png?18

GFS

A difference of difference as per what JH has just been saying

http://modeles.meteociel.fr/modeles/gfs/runs/2014122218/gfsnh-0-138.png?18

Certainly moving away further to the South than the 12z , lets hope the trend continues

18Z has 552 isopleth about 50 miles further north, doesn't sound much but it almost certainty will be a vastly superior run down the line. Fully expected a superior 18Z because of regression to the mean. Still on a knife edge, but both opportunities of reloading (when the wind is northerly and when the wind is southerly) are both on the table. A south easterly facing low almost never breaks through (even the weakest of blocks) whereas a south westerly facing low almost always breaks through (even the strongest of blocks).

Looks like the High is still sinking into Euroland though. Just delayed slightly. 

That was only 50 miles further north of the 552 line at 120 hours, 200 miles further north at 120 hours is still possible....

But yeh, its still an awful run but compared to the 12Z we are looking at a significant improvement. Hopefully the 0z will be an upgrade on the 18z.

Oh no, not here again...

Million miles out in forecasting terms anyway. Watching the runs flipping like an overcooked egg each day for the last week or so has been amusing though.  

552 line also much further north on the NAVGEM, in fact its more pronounced here. 

LOL I see where this is about to go, shows how a little more amplification can make a huge difference.

Another 2 GFS runs (18z op & parallel) going with the sinking High scenario. If that happens we could be in for another 2 weeks of mobile westerly weather at least. It would basically be a re-load of what we've seen through most of December.

GFS could be wrong of course but who would bet against that evolution? Seen it so many times in the past. With the 12z ECM closer to GFS, the UKMO 12z projection is looking a bit isolated this evening. 

The NAVGEM is on the UKMOs side, and the 18Z suite is undoubtedly an improvement on the 12z. Its odd that the worst GFS run comes after one of the best, the 6Z was very snowy.