casparjack

That's true, but the 528 on the earlier runs is well North, much further than I had hoped, I have an awful feeling that unless we have a significant change, that much of the precipitation at lower levels will fall as rain for the first 24 hours in the Midlands and areas South of them. I appreciate that there is cold air at the surface, but if you look at the 850s on the radar overlay they don't support snowfall and I can't see that changing for 36-48 hours where I am, even though I am over 500 ft amsl...

Rather worryingly it's already showing up as a huge feature on the Netweather radar, been watching it for a few hours now...

I suspect that might come down to the origins of the models, US against European - don't know for sure just speculating...

I think the point is that all the models handle mild weather much better, as they are more familiar with forecasting it. Synoptics such as we have at the moment have probably cropped up less than ten times in the past 25 years, there is no wonder they are struggling with the details...

I totally agree with that TEITS, but the current fax charts, albeit quite a long way out for this kind of scenario are showing a very marginal event 'snow-wise' initially in the lower levels of the Midlands to start with. The simple fact remains that we don't know for sure for another 24 hours - that's part of the fun though isn't it!!

I agree that's possible as far as a new trend, but my 'gut' feeling is that genuine trends should show up much further out and more often when the other models are less in tune with one another. ..as ever though, it could still verify, but seems an outside bet at the moment.

Could be a ZX80!! ...but seriously, I think there is such a tight margin between rain/snow in the initial event that we might not even know in any real detail until it actually starts to happen on the day!!

...melted in his blowtorch?

Only just had a look at the ECM 12z, seems to be a reversal of the ideas that were developing yesterday, this cold air seems to be rather more stubborn, rather like the old days... Off to have a look at the other models now, with renewed enthusiasm!

Having had a little time now to consider the GFS 06, it still looks as if the cold air is likely to be the winner certainly from the midlands north right through to New Year's eve. As we have all said there are definitely many twists to come yet that the models just can't handle, but I think the underlying trend is encouraging in that there is tacit agreement for sustained cold/rather cold for the entire model run.

It looks to me like a complete blend, taking the trend shown on ECM to go with cold overall, but allowing for the GFS indication of some mild encroachment so as to 'hedge' their bets. Overall I feel that the colder scenario will prevail, though as many have said on here there will be an element of mixing out at the edges, but as we all know and keep saying, well established surface cold is difficult to shift, especially when there is an absence of a really strong push from the Atlantic to introduce a pattern change.

I agree, seems very odd, is there any fog in the area, that would seem to be the only potential explanation?

The ECM looks to keep the cold theme going at least through Christmas day and the latest FAX charts show the attempts by the milder air attacking from the south being repelled, all shaping up quite nicely I would say.

Don't you think it's ironic that only four or five days ago it was the ECM that 'downgraded' in one run and the whole thread was on the verge of jumping off a cliff in anticipation of the next run whilst the other two principal models held with the cold/colder theme, then ECM came back in line and here we are tonight. Now it's the ECM that's leading the idea that we might not even have a mild interlude, just a less cold spell whilst things reload. I feel that there is definitely more to come from this winter...

The renewed N' blocking trend has popped up a few times in the past few days, I have no doubt that it is a trend for the new year...

I saw that and had the same immediate reaction as you, but don't you think the source of the air spoils it, the near continent has warmed up considerably by then?

I have no doubt that it will change, whether towards cold or mild, however, no one really knows. The FAX chart for Monday that I posted earlier is a perfect example of how complex the situation is and frankly that's what makes it so interesting - isn't it!! ?

Only just had time to look at this, so apologies if it's already been talked about... ...but it looks like a really marginal situation for anywhere south of Manchester/Lincolnshire to me for Monday, I know there will be some decent surface cold air, but the source to the SW looks like it might spoil the party to an extent. Many changes possible between now and then though!

-26.1c - Edgmond, near Newport, Shropshire on 10 January 1982. I remember it well, it fired my interest as I lived just a couple of miles away as a kid...

TEITS, here are the ones I had in mind, do you think we will see light winds and clear skies under these conditions - I hope so, but I'm sceptical. The potential is there, I just think the set up will be too 'busy'.

I agree, but I'm not convinced that we'll see sufficiently clear skies and slack winds will we, I'm struggling for the chart, I'll post it in a sec. Not being negative, I love extremes, that's my my whole interest in meteorology.

On the ECM T+168, the Scandi high is upto over 1050 Hpa, it really seems to be giving the signal that others have picked up on of a reinforcement from the North, the block doesn't seem to want to give way.

...now the T+144 looks much better, the warmer uppers appear to have been repelled!

The T+120 looks a little worrying, cant get T+144 yet...

UK Outlook for Saturday 19 Dec 2009 to Monday 28 Dec 2009: Cloudy with rain, sleet or snow in the north throughout with some significant snowfall possible over high ground and hills in Scotland and northwestern England. Most southern and central parts should be dry and cold with bright or sunny spells at first, but cloud and rain, sleet or snow in the north will gradually spread southwards to many areas during the week. Temperatures are likely to be rather cold or cold throughout, especially overnight, with frosts and icy conditions in many parts. Over the Christmas period it is likely to remain unsettled in most areas with further outbreaks of rain, sleet or snow. It may become milder from the south towards the end of the period. Updated: 1231 on Mon 14 Dec 2009 Another wishy/washy, let's include a bit of everything forecast - it's clear they're as uncertain as we are!!