Yes, certainly looks like some warmer and wetter weather end of the week, however a switch back to blocking still on the cards the week after. GFS still has plenty of blocked runs past day 10. (FI I know) and this consistent with ECM.

No sign of the zonal train.

Martin

The lack of aesthetics should not take away the value of the UKMO model. This shows an Atlantic incursion but keeps the jet NW-SE into France and a dumbbell pair of low pressures straddled across the Uk by T144: These should follow the Jet and nestle into southern France, doloping even more snow on the Alaps (early joy for skiers), and ensure a decent HLB behind it - nicely set up for the run-up to Crimbo. For me - Santa can bring me a re-run of 1970-71 - that’s all I want for Christmas!!

I’m puzzled by your thoughts because in the next week I don’t see anything in the output that suggests it will turn mild.  What I see is the prospect of a stuttering jet stream still on a track to our south, keeping us predominantly on the cold side.  There’s ample evidence of a rather blocked pattern persisting but the uncertainty is around how that influences our weather.

The comment about the Net Office having to change their forecast is a perennial nonsense: we all know that they have access to more data, more skill and more experience than anyone here. If the signals show a consistent change then their forecast will reflect it.

What cold air?

Just before the change to cold weather just after Christmas 1978 the temperature in the Baltic states was -20/-25C or below. As i write this the temperature there is above 0C. Last night I watched a live stream of the aurora over the far N of Finland - the temperature there is barely below zero and there is little snow.

Lets get real.

Yes startling numbers and indicative of the modern era, the ECM later on is an incredible almost late Spring type chart such is the lack of cold air over Europe.

Yes this old pipe-puffer is rolled out every year. The UKM extended forecast is not always perfect - no LRF can be - but what it doesn’t do is react to the fragility of six-hourly output, even when by some miracle the extended range of said output shows some consistency over several days. They have far more data available and make sub-seasonal forecasts based on probabilities and trends and by definition react only gradually to changes in those trends.

Personally I’m glad they don’t change as dramatically as the output does, and is one of the reasons I take the wording as one of the best guides to the longer range outlook there is. Not saying they shouldn’t be examined and criticised of course - as any forecast should.

I disagree, we have seen the NWP lead the METO longer range outlook many times, often seeing colder outlooks dropped as the NWP (that we see) continues to show milder conditions prevailing.

Look at the current conditions by all means or maybe think a little more about if the pattern gets in place how quickly that would change. I am talking about the high being better aligned and not mixing air from a warmer source. This is being hinted at in time for Xmas week. Enjoy the model watching

Liking the unusual  pattern this winter.The common theme of persistent above average upper level air temps to the north east is amazing but that doesn't mean as weve seen last week the UK wont get hit by lots of marginal snow events this winter to make it memorable.Classic spring snow in winter !!!!! We are the spread in the sandwich this year and that spread is wet snow.

Quite, Peter.

I have also made the point you make in your second paragraph to others who seem to have a habit of second-guessing what the Met Office might or might not say in their later updates, and how IMO this is a rather unwise thing to do. Some don't seem to listen though, unfortunately.

The last time that I predicted that they would change their outlook - in mid-November - they did so the next day !

Be that as it may, it doesn't take a great deal for temperatures to drop noticeably pretty quickly over a large continental land mass such as mainland Europe at this time of year if the synoptics which allow it come to fruition. Just like temperatures there can and do shoot up very quicky in the spring and summer when the right synoptics prevail. The same is true of much of the USA as well.

There couldn't have been a lack of cold air over northern Europe during the times of our recent notable cold spells, e.g late Feb/early March 2018, March 2013 plus December 2010 and mid-December 2009 to mid-January 2010.

Stylus stuck in the groove as usual.

You’re actually contradicting yourself here and agreeing with me. The point I was making is the whole NWP suite (short, long, seasonal, paywall, etc) are used to shape the UKM extended text but they’re not as reactive as you’d like them to be thank goodness.

And although this doesn’t compute with you, they will change their wording to reflect any charge in outlook - not just to milder.

Did they stick with their altered thoughts though?

From what I have read of their updates in recent weeks, there has been a fair amount of altering of their thoughts to one degree or another, which is only to be expected given the very unpredictable nature of the model output lately.

If you make enough predictions you're bound to be right occasionally, Ian.

Your prediction for last week wasn't so great, was it.

Why not call it by its proper name? It's climate change; it's real and it's pushed up our temperatures by over 1c so far. Then there are the impacts on prevailing weather patterns: Brian posted a chart showing the slight, but noticeable, rise in pressure to our south.  Against that we have an apparently increased frequency of the jet stream meandering and getting stuck, bringing greater extremes of heat/cold, wet and dry.

As for the 00z ECM, it is neither 'incredible' nor is it uniquely 'Spring type' and nor is it even especially mild: daytime maxima around 7-9c.

It is when you see that the source of the air is East of South and from mainland Europe ! ...in mid December

There wasn't, but there is now and that is clear from the charts. Unless there is a seismic shift in the pattern, looking for meaningful cold from the East is futile regardless of how 'non-zonal' the synoptics may be.

https://modeles.meteociel.fr/modeles/gfs/runs/2020120606/gfs-0-246.png?6

GFS pretty consistent with it's 00z run, the big +ve height anomaly that the ensembles have hinted at for Iberia and France is well signposted here.

The biggest anomaly at that point is actually to the west of the British Isles, but no need to let little things like facts get in the way of your narrative.

The end of the 06 gfs run shows how quickly cold air can start to flood down into Europe. Three days later that could be across us with HP in the right place. All of course will change, but to just show how quickly things can change in 6 hours worth of runs and also how quickly warmer can become colder!
Martin

Seismic. 

Yes the GFS 6z very nearly gets us too the promised land late on. And continues the theme of lots of HLB starting to shift into favourable position for the UK around 20th December.