The Run Up To Winter 2011/2012- Signs Of A Cold/mild Winter And The Autumnal 'building Blocks'

[johnholmes]

BFTP

thanks Fred

In there you have given your views on the main teleconnections that you look at, and where you feel they are, along with a very balanced view as to their likely resultant weather pattern.

More like that post would be beneficial to this site rather than some of your posts from last winter.

thanks again.

[Cheshire Freeze]

Just had a quick nosey at the CFS pressure anomoly charts for Nov-Feb and I must say that striking high anomoly over Greenland has been well watered down in just a few days! In fact there is now no signifficant anomoly showing anywhere in the world for next month really(when compared to the anomolies shown for other months).....this is odd and suggests that either there is likely to be little deviation from average pressure distribution, or there is wild deviation in the data with the median solution being fairly central and thus being reflected in the output. Either way, after months of the striking anomoly showing over Greenland, a fairly major shift has occurred.

http://www.cpc.ncep..../glbz700Mon.gif - Latest Update/Rolling average

http://www.cpc.ncep..../glbz700Mon.gif - As it was last week

Edited October 19, 2011 by CreweCold

[ribster]

Seeing as some of the more narrow minded (some of whom should know better) were adamant there are no such things as building blocks etc, I decided to contact the MET Office regarding the question of whether the weather today has any bearing further down the line, i.e. patterns establishing etc. The answer was yes sometimes the weather today will have a bearing/shape events weeks down the line, other times it will have no bearing whatsoever. An example cited was the cold snap last year, suggesting that not only would it occur, but that it would become established for weeks. So in my view, those suggesting building blocks are in place are not wrong in doing so, it is entirely plausible. Of course at the same time, a case can be argued against also, but to simply dismiss out of hand is clearly wrong.

Edited October 19, 2011 by ribster

[Liam J]

Seeing as some of the more narrow minded (some of whom should know better) were adamant there are no such things as building blocks etc, I decided to contact the MET Office regarding the question of whether the weather today has any bearing further down the line, i.e. patterns establishing etc. The answer was yes sometimes the weather today will have a bearing/shape events weeks down the line, other times it will have no bearing whatsoever. An example cited was the cold snap last year, suggesting that not only would it occur, but that it would become established for weeks. So in my view, those suggesting building blocks are in place are not wrong in doing so, it is entirely plausible. Of course at the same time, a case can be argued against also, but to simply dismiss out of hand is clearly wrong.

A large percentage of the so called 'building blocks' were charts that were picked out of deep FI by a few members and ramped up because they spotted a potential set up for cold weather, the charts have subsequently vanished from the model outputs and this thread has gone very quiet.

I have no doubt that the current pattern will have a bearing on the weather further down the line - as it occurs quite often through autumn and winter and is highly likely to repeat itself many times. I dont' see what your point is on that one?

The arrival of the cold spell late November 2010 wasn't picked up months in advance by looking for building blocks in October, Long range forecasts can and have gone very wrong even for the most experienced forecasters who analyse many many sources of data to create them. The Met Office give up producing long range season forecasts to save their reputation after they went horribly wrong.

[Snowmad79]

This mornings 00z GFS chart again show a tendancy for height rises to our north east and the north/nw, with warm air advecting towards Greenland and HP gaining influece over a wider area, not just a little pool of low heights centred over GL and thus actually having the effect of a "weak" Greenland High Block. Only going back to last winter we saw similar things and even when the models dropped the idea they re-emerged later and came to fruition.

The run is mild in terms of UK weather but what the charts again show this morning is how a GL High block can form out of a seemingly atlantic dominated outlook and what we need to see more of as we head towards and into winter.

Edited October 20, 2011 by Paul
Removed response to an already deleted post

[Liam J]

I am not totally discounting the theory regarding the early signs and building blocks which can lead to cold and snowy weather in the coming months over winter, my point I was trying to get across was that perhaps experienced meteorologists would have picked up on this in the past and then have been able to identify early in the season what this actually meant in terms of weather we can expect in the near future.

Long range forecasts do still go wrong, so this theory needs much more investigation before anyone can can say with confidence that potential building block synoptics do have a bearing on the weather some months down the line. Equally at the same time nobody can claim with any confidence that no link exists.

I'm sure this thread will keep going through winter so we can keep the discussion on this subject open, the buidling blocks that we see appearing now may or may not come to fruitition - hopefully not as early as last year because the final two months of last winter were painfully boring and lacking in anything remotely interesting!!

Edited October 20, 2011 by Paul
Removed response to an already deleted post

[johnholmes]

I suppose it depends on what you define as 'building blocks'.

I do believe that what the synoptic models are showing at the moment has nothing to do with how the 3 winter months MAY turn out.

It is true that certain weather types once set up do take quite some time to be changed. Remember last November into early Decemeber. The cold associated with that was not really broken until we were into january.

What caused the change?

Did any model predict the change to less cold some 3 months before hand?

Are we able to routinely predict what the weather pattern, as opposed to precise weather deatails, that far ahead?

Are there any links which do this on a better than 50% basis?

There is some discussion on how reliable could certain values in the AO and NAO for predicting what the winter may be in Britain-to me its far from proven either way about either of them.

Others disagree-that is fine-we are all entitled to our views so long as we respect each others' views.

I find the attempts on various sites including professional centres quite fascinating and am open to the various ideas, some mainstream meteorology others from viewpoints which do not yet have much if any support from that area.

It sure does make for interesting reading and research.

Edited October 20, 2011 by johnholmes

[shedhead]

If you buy into this 'building blocks' theory, which incidently I don't, you could argue that this time last year the blocks were already far more clearly in place....

Mind you, 2003's 'building blocks' looked pretty good too... how did Winter 03/04 turn out?

Edited October 20, 2011 by shedhead

[Paul]

I agree, charts in isolation surely can't be talked of as building blocks. A chart + some explanation of other longer term signals which perhaps tie in with it, then there's more scope for discussion.

[Coast]

Nice article on the upcoming Winter from Irish Weather online - I've copied some of the more interesting parts into the media thread here:

[Don]

Winter 2003/04 was mild overall, although it wasn't bad for the 1997-2008 period! The overall CET was 5.1C

Edited October 20, 2011 by Don

[Liam J]

UK Outlook for Friday 4 Nov 2011 to Friday 18 Nov 2011:

The early part of November is expected to be unsettled with Atlantic systems moving from west to east across the British Isles. Northern and western areas are expected to see the most persistent rain with strong winds and gales at times. The southeast will be most favoured for some drier and brighter interludes. Overall temperatures, rainfall amounts, and sunshine totals across the United Kingdom for this period should be around average for early November.

Updated: 1237 on Thu 20 Oct 2011

Meto continue to predict unsettled weather into Mid November, temperatures around average.

.

[ribster]

No, as someone has said, one chart in isolation cannot be defined as the building blocks. However, I have categorically had it from the MET Office that the state of the atmosphere today, can and sometimes does have an effect on the weather that we get weeks down the line. At the same time they advised that at other times it has no bearing at all. So I don't see what the argument is, only relaying what I was told by the professionals.

[bobbydog]

No, as someone has said, one chart in isolation cannot be defined as the building blocks. However, I have categorically had it from the MET Office that the state of the atmosphere today, can and sometimes does have an effect on the weather that we get weeks down the line. At the same time they advised that at other times it has no bearing at all. So I don't see what the argument is, only relaying what I was told by the professionals.

of course todays weather has an effect weeks down the line! we all know that.

the art of forecasting is to predict how it evolves. days, weeks, months down the line

[Liam J]

No, as someone has said, one chart in isolation cannot be defined as the building blocks. However, I have categorically had it from the MET Office that the state of the atmosphere today, can and sometimes does have an effect on the weather that we get weeks down the line. At the same time they advised that at other times it has no bearing at all. So I don't see what the argument is, only relaying what I was told by the professionals.

Do you have any replies from the Meto via e mail you can post out of interest with a bit more explanation? or was this a telephone conversation?

Thanks

Edited October 20, 2011 by Liam J

[SP1986]

The problem with building blocks is that they are not a guarantee of winter, those building blocks may actually be evident, but all it takes is a train of Atlantic lows to wipe away these building blocks, especially if they exist in the east, and are not sustained by a Greenland block. So as everyone knows, even if there are building blocks emerging, they shouldn't taken as sign for the start of anything grand, or long lasting.

There were numerous times in 2006/2007 when people saw these building blocks, and they did not, for whatever reason, come to fruition.

I do agree building blocks can emerge, but it's fairly obvious they don't always sustain - think for example of this summer just gone.

[bobbydog]

i think the only 'building blocks' are the things that create winter in the first place - the earths tilt on its axis, which causes less daylight, therefore it gets colder.

the 'building blocks' people are talking about are only really in the short term, for a particular scenario. they can only really be seen as they happen, i.e. high pressure over greenland, southerly tracking jet etc. no-one knows for sure if these things will happen in advance but when they do and can be seen to be happening, then maybe they can be called 'building blocks' but only for any given weather scenario and in a relatively short timeframe. even then, we have all seen the ideal scenario evolving perfectly, only for it to come to nothing.

i for one dont think we can write winter off before it has officially even started. even the experts will not say how things will pan out- because they dont know! they give us an idea of what might happen, not what will happen

[Cheshire Freeze]

The problem with building blocks is that they are not a guarantee of winter, those building blocks may actually be evident, but all it takes is a train of Atlantic lows to wipe away these building blocks, especially if they exist in the east, and are not sustained by a Greenland block. So as everyone knows, even if there are building blocks emerging, they shouldn't taken as sign for the start of anything grand, or long lasting.

There were numerous times in 2006/2007 when people saw these building blocks, and they did not, for whatever reason, come to fruition.

I do agree building blocks can emerge, but it's fairly obvious they don't always sustain - think for example of this summer just gone.

True, but I associate a hot, dry April-May period with a cooler/wetter summer so to me that would be a building block in the opposite direction.

[bobbydog]

True, but I associate a hot, dry April-May period with a cooler/wetter summer so to me that would be a building block in the opposite direction.

can you provide any long term statistics to back that up?

[BLAST FROM THE PAST]

I agree that a synoptic chart or two are not building blocks.

[SP1986]

True, but I associate a hot, dry April-May period with a cooler/wetter summer so to me that would be a building block in the opposite direction.

The fundamental question is, when does a building block become a building block, and when does the building block cease to be a building block and become the actual event. Also how does a potential building block interact with various possibilities? Of course if we knew that...

[johnholmes]

I'm afraid the term 'building block' is yet another example of using a rather clever sounding name which has little to support its use in reality. Sorry to be a killjoy but its a feature of folk on the web I suspect trying to sound rather clever!

Obviously one can use such a phrase but it is overused and seems to lead, reading through this thread, to a touch of impatience with one another in just a few cases?

The term teleconnections is another that has got into use since the web gave us all so much weather information-not a bad term and handy to use rather than the term building blocks as we can actually relate some rough time scales to most of them, AO and NAO, 500mb anomaly charts, MJO, 30mb temperature profile, ENSO; all can be given some kind of time scale in which their effect is most felt.

[Snowmad79]

So the models repeatadly showing height rises to our NW, N and NE along with a southerly tracking jet and WWA up north aided or infact initiated by low pressure which can make a high more robust in terms of becoming more sustainable and evenutally having the effect of a NH block, cannot in the slightest be called a building block for a future weather pattern ?

I suppose it depends on what you personally define as a build blocks really. As I understand things, the NAO and AO are drivers of weather but you dont get a Negative NAO with LP dominating the Iceland/ Greenland area do you ? and High pressure over that area does infact need Warm Air (via advection ?) to become more rebust thus forcing the NAO negative ?

Or have I missunderstood ?

My post this morning is amatuer but thats all I am and they definately werent isolated charts. The models have shown height rises to our NW, N and NE, which I believe is important for a potent cold spell to develop (not just for a -Nao).. down the line.

I think in reality we are using this thread becuase if you post about charts in FI and try to discuss what pattern could emerge from them (even if it doesn't turn out that way in the end) and they are related to colder weather, you get shot down by the mild weather fans.

[Robbie Garrett]

Comparing the Actual chart 6th Nov last year to this years 6th GFS forecast. Clearly showing high pressure that we need for a Northernly block is forming to our south west, so why's everyone going for Above Average/Average? Nice cold airmass to our east too But at the end of the day, maybe it's a good thing that we are having all these LPs running through a bit now instead of at a later date.

But I have to agree, last year's November end spell would be remarkable to be repeated this year. If anything's going to be coldest, it's probably going to be December. I'd give it two weeks to calm down a bit, and see where we are at.

Edited October 21, 2011 by Robbie Garrett

[ITSY]

The danger is what happes in late FI in the 12Z GFS. A huge Blast from the East heads our way only for building blocks to allow troughs and atlantic dominated weather to 'bail us out' and leave E.Europe in the freezer (-4c by day) and us in a comparitvely balmy 14C. In other words, don't use the emergence of blocks at this stage as the holy grail to clues of a cold winter - it could simply lead us the other way. One thing is for sure though, model watching of the next 2-3weeks will start to become more and more interesting as the possibility that one of these highs could deliver cold increases with the onset of winter.