TEITS
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As you know Dave the blocking was there for August - just 300 miles to our west. However, August may have seemed poor to you and some others but this is where statistics provide a useful corrective to mistaken personal perceptions. At 16.1C August was within 0.1C of the 1971-200 average, and comfortably warmer than both the 1961-1990 average (15.8C) and the 100 year rolling average (15.9C). It was of course a relative dull month, and whilst wet in much of eastern England it remained bone dry in much of the west (30% of rainfall totals in our parts!). All in all it was therefore an average month. The mood was lightened by a thumping warm September breaking the all-time record.
Statistics do have their uses, providing the source is rigorously tested.
August didn't seem poor it WAS poor!.
It doesn't matter what the temps were the fact is it never stopped raining here in Peterborough and this is why I classed it as a poor month. The garden was proof of this because as you may remember the pic's on my sig used to show the brown dead grass of July which was changed into a lovely lush green within a couple of weeks in August.
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I don't think being so near the north Pole really comes into it. The prevaling flow in the UK is south-westerly, and we are first in line from the Atlantic. Add to this the gulf stream and you can have all the cold you like to our north and east, if the west / north-west isn't right it won't come our way ... at least not for any sustained periods. The Atlantic will always return. Even with a blocked set up last year we didn't get a properly cold winter. The final nail in the cold coffin.
Whilst local variations to the general AGW trend are always possible, and it would be foolish to deny this possibility entirely, the chances become rarer with each passing year. As more and more warm records tumble around the globe it begins to look more and more desperate for those clinging to cold hopes for the UK. Personally I'd rate the chances of a below average winter now in the UK as 1/25 or 4%. This is reinforced by the full-blown return of the Atlantic this autumn.
I'm looking to record mild possibilities rather than the other way.
Morning Richard.
May I ask where you are getting the return of the full blown atlantic from??
http://www.wetterzentrale.de/pics/Rtavn1441.png
http://www.wetterzentrale.de/pics/Rtavn2641.png
As for the chances of a cold winter becoming rarer with each passing year may I ask you what would happen if the factor's that made the 90's so mild were reversed in the next few year's. GW is only a tiny part of the reason why the winter's since the 80's have been so mild and it look's to me the other reasons are on the change.
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The problem is that you are assuming that statistical analysis only involves looking at basic variables for the previous years. It's worth pointing out that the complex teleconnections used by Steve and GP are based on statistical analysis. It just emphasises the point that statistics is key in every branch of science.
Which is why I say using stats are ok to a certain degree. SST's have a major impact on our weather and yet we know how quickly these can change and im sure GP/SM are closely montioring these over the next 6 weeks.
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Thank you for your reply
My point about statistics was not to suggest that they cannot be extrapolated forwards to base future predictions/outcomes if used properly - because indeed they can. It was to suggest though, that a line should be drawn when they are not used properly or as a tool alone without taking into account newer factors or shorter term drivers which may flesh out and put a different perspective of future predictions and possible outcomes. In that way, a statistic will tell you what has happened but it is not neccessarily a guide to what the future may hold.
You are absolutely right SP.
Assuming our future weather based on previous year's is a rather basic way of looking at our climate and isn't taking all the factor's in that make our climate. As an example our winter's since the 80's have been largely dominated by a positive NAO resulting in a rampant Atlantic with little high lattitude blocking. Now suppose the next decade bring's a return of this high lattitude blocking with more frequent occurences of continental/artic airmasses our winter's would be far different to those in the 80's.90's and would render the stats on the 80's.90's as being pretty useless.
So you are quiet right SP Statistics are ok if used properly but you need to look at all the influences that make our climate. I believe you should judge each year on it's own merits and when it's comes to what to expect this winter I prefer to look at the sign's in Autumn e.g SST's/Teleconnections rather than look at stats for the previous years to base a forecast for the oncoming winter.
Let me say this how many people on this forum expected August to be as poor as it was after the blazing hot June/July??
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Some very interesting post's on this thread about LRF's but I think we need to be clear on the different types of LRF's. Now it is my belief that LRF's that go into detail e.g week by week details of weather and synoptics are just pure guesswork when forecasting 3 months ahead because we struggle making detailed forecast's 14 days ahead!. However LRF's that just stick to whether temps/rainfall are going to be above/below average by using SST's/teleconnections for example are more realistic and it could be argued have a higher success rate than a detailed forecast for the next 14 days.
I personally enjoy reading all types of LRF's on this forum and whether these are based on instincts, hopecast's or science I find these are not just enjoyable to read but a great learning tool especially from the like's of GP/SM.
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The "fort" will be lain low by outcome over the years, SF. I can't help that, neither can you, neither can anyone. The wishers for cold can fight the "battle" for as long as they wish, but in a warming world, there will be fewer cold spells, cold winters and "victories". Reality is a domain the cold-wishers find hard to inhabit!
I don't actually take that military analogy at all. I'd lust much rather operate within a schema that gives probabilities which have a reasonable accuracy and not one in which my hopes are likely not to come true.
Paul
Until GW completely removes the possiblity of a cold winter the cold lover's on this forum shall continue to be in full force. Beside's this who know's what the future brings and without the aid of either a crystal ball or a time machine there is no way we can be sure what our weather is going to be. To assume our future climate is going to be warmer just because of recent warming is rather foolish IMO and lacks an understanding of our climate.
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Whilst we are discussing classic winter chart's I shall post my favourites.
During the winter you will often hear the word "TRUE Greenland High" now the chart's below show a true Greenland HP and not one of those fake one's you see the GFS outputting every winter!. The exceptional 1981 event began with Artic air flooding S on the first chart. On the 11th heavy snowfall occured in the S due to a LP running along the Channel. After this snow event Max temps only reached -12C in Shawbury and was followed by min temps of -25C, even by early evening the temps had dropped to -22C!!. This was caused by a combination of light wind's/artic airmass/snowfall and was IMO one hell of a freeze.
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In all truth, as I'm sure you all know - looking at specifics on these charts is pointless. But I've been following it for a few days now and this system does seem to maintain trends very well - for instance a southerly tracking jet during december. Time will of course tell as to whether it maintains these right up to the time though..
Just to even things up a tad, here's the chart for new year - not so good for the cold lovers!
I may take these chart's with a dose of salt but I appreciate you posting them Paul.
P.S Please don't post chart's like the New Year one because it upset's the ramping :lol:
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Now that we are coming into a reliable timeframe I think BFTP has made a good point here - that won't indeed be far off what happens! :lol: ....
.....
cough!
Amazing chart...sigh!
Tamara
Look's like we could be spending Xmas day shovelling snow instead of eating turkey SP.
Stunning chart especially for E area's.
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Is it out yet? Cant wait to read it.
Here we go a the link below is selling it for £11.99. I shall certainly be buying this.
http://www.play.com/Books/Books/STGCS4/3-/...me/Product.html
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HI Boot, good riposte.
Clarify away Dawlish, myboy!
Don't attribute 1990 as the start of the trend to me. 15 years was the time period that BigBear asked us to research similar length periods in the Hadley series for him. If you think there's a 15 year trend, that's fine by me. For me, the UK began to warm in the early to mid 1980s. The world has been warming longer - see the graph on the NOAA site that P3 has referred to on another thread. There has not been a negative annual temp anomaly, since 1979 and the earth has been warming for at least double that time; a trend can easily be seen back to the early part of this century, with a warmer spell, peaking in 1940 - the warming Arctic period that you refer to.
Regards, Paul
The problem is though Paul is GW actually responsible for the mild winter's since the 80's or are other factor's responsible. There is no doubt the earth is warming but I don't think it's quiet as black & white as you make it out to be.
Could our mild winter's since 1980's be down to:-
(1) GW
(2) GW affecting our synoptic's
(3) We are just going through one of earth's natural warm cycle's.
(4) Sunspot activity
(5) GW combined with warm cycle
(6) Teleconnections Note Negative NAO during 60's and positive during 80's/90's
My answer is a combination of the list above with (2),(5),(4),(6) being responsible. Now suppose these next few year's we go through a spell with low sunspot activity, Negative NAO like the 60's, change in the synoptic patterns with Northern blocking being dominant rather than LP. We would see winter's like those in the past only the severity and duration would probably be less due to GW.
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Thank goodness for some decent argument away from the......"it was colder last winter, so we've got a really good chance of it being colder this winter", stuff. And no-one getting upset! Marvellous!
After reading the post's on this thread im not sure that is a fair reflection of what some have said on here. By what I have read member's like SP commenting on the fact that last year not only did we have the synoptics but the record breaking cold pool in Russia proves a cold spell like 81/87 is very possible. Like SP what we need is the two of these to come together.
Let's face it nobody know's what is going to happen this winter but you cannot assume this winter will be cold just because of last winter but equally you cannot expect this winter to be mild just because of previous mild winter's. If using past weather to predict the future weather was so easy then many LRF would be far more successful. You need to judge each winter on it's own merit's so the best way of getting an idea for this winter is to keep a close eye on the latest data SST's for example over these next 6 weeks.
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Slinky, you just can't have a one-year trend! Good odds on my "betting" thread if you think that will come true, though! :lol:
Actually your wrong Dawlish and Slinky is correct.
The word trend mean's a general direction in which something is developing or changing. When you consider the last two winter's we have seen a greater frequency of blocking compared to the atlantic driven winter's of previous years. So what Slinky mean's is he believe's last winter's synoptic trends will continue into this winter.
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Hi John
Even taking into account the possibility that the same depth of cold isn't around as once was, you are still quite right to say that it was indeed a close call. -15 850 temps would still be capable of delivering ice days and heavy snowfalls.
Any 'loss' of degree of cold is not sufficient (at least yet) to prevent noteworthy cold weather/snow potential to compare very respectably with yesteryear. The warming effects (in the here and now) are being overstated by some and still premature.
:blush:
Tamara
This is exactly it isn't SP we are not expecting another 62/63 or 47 but another 81/87/95/96 is quiet achieveable. I think some need to remember the CET during the last winter, Dec 05 4.4C which is 0.7C below the 71-00 average, Jan 06 4.3 +0.1C, Feb 3.8C -0.4C.
I admit the synoptics since 87 have made a very cold winter less likely but not significantly so as Dawlish suggest's. Beside's this these past 18 month's has seen a change in the synoptic patterns compared to recent year's and this IMO gives hope this winter. I think those who keep banging the GW drum are going to be in for a fall one of these day's because our climate hasn't changed significantly enough to prevent another cold spell like in those year's I mention.
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I think it's more like AGW we are paying for. Whilst this will not cause an entirely linear progression to warmth, it's the main reason why I think this will be a very mild winter. Last winter was an example of the effects of AGW: even with all the right synoptics we only ended up with an average winter in most parts. This winter I expect nothing like such favourable synoptics for cold, so a very mild one is in the offing I think.
Glorious day today mind you. Was working outside in shirt sleeves and got sunburnt. Not everything about AGW always feels so bad! I'll be happy to get through to spring with lots of mild weather, but hopefully with plenty of rain to replenish the reservoirs.
Don't forget WIB on the 29th Dec 2005 the Max temp was only -4C in many area's including Peterborough which would of been considered very cold even in the good ol days.
GW may have moved the goalpost's somewhat but not as much as some suggest on here. May I also ask what is your reasoning for a very mild winter and what's the reasoning for unfavorable synoptic's?. Don't take this the wrong way but these past 5 month's you have been expecting endless HP and a quiet atlantic due to your preference of warm weather and it seem's odd now summer is at an end you expect HP to go AWOL. I hope your personal preference isn't clouding your judgement because let's face it neither of us have enough knowledge on LRF's to really make any kind of forecast for this winter.
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what was the winter average in 1941/1942 eg. dec,jan,feb
Some great chart's for you to look at.
http://www.wetterzentrale.de/archive/slp/1...slp19420217.gif
http://www.wetterzentrale.de/archive/slp/1...slp19420224.gif
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I am entertaining hopes of snow this winter, but then I always do even when the LRF is for mild. I found the idea of a low CET very interesting but wont get disappointed if it doesn't come off. I promise there will be no recriminations from me.
I think many of us on here deep down expect another mild disappointment but there is always that slight chance another 78/81/87/95/96 could happen. It is this that keep's us all addicted to the model's throughout the winter month's. I know for a fact come November 1st my excitement start's building
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I agree entirely with your last sentence Steve and much of what you say and I'm glad my points have raised the discussion. The more research, the better. There is a key in there, it just hasn't yet been found.
Your 90% success rate, quoted there and just so nobody comes back with this, as figures like that tend to stick, is not a prediction success rate. I do appreciate it could bode well for the future.
Again, I mentioned that no-one, to my knowledge has achieved a 70% success rate at predicting seasonal weather accurately. That actually means that the success rates are less than 70%, maybe 2 out of 3. The Met Office and others, have a number of paying customers and some large utilities either increase, or run down their stocks, based upon the LRF they pay for, that is true; last year's leak of the "colder than average winter" came from an ill-advised article by a UNISON member, following a Met Office presentation to their commercial customers, on exactly that topic, but only 2/3 is one hell of a gamble and I'm sure they know it. It would not be hard to imagine the furore when a cold winter does come along (and it will) and the 1 in 3 chance of the forecast being wrong drops on that year (which, statistically, it will). It is that which will be remembered.
The number of commercial customers has grown in recent years and their expectation of getting their money's worth, with a correct forecast has grown with it. I only hope that the advances in forecasting techniques improve before the combination of a cold winter and a less than 70% success rate collide.
Paul
PS If I'm wrong about the <70% and an organisatiuon has demonstrated a >70% accuracy, whose dataset is statistically significant at the 95% level (ie is long enough to demonstrate reliability), tell us, anyone, please. WF? You seem to have some knowledge here? Now that would be a forecast worth investigating. I know Piers Corbyn claims a success rate greater than that, but he has never made his research available to the scientific community, claiming (perhaps rightly) commercial confidentiality.
Im curious Dawlish at what timeframe do you class a forecast as being a LRF week,fornightly,monthly,seasonal?. The reason I say this is because due to our varied climate I believe any forecast beyond a week in the UK can be classed as a LRF. Because of this I would rate the Met O weekly,fortnightly forecast's as being very accurate.
Another point I wish to address is your comment in your sig "Event Spot 90% success". Now Im not having a go but I think im right in saying that you use the GFS for these spot's?. Do you wait to see a pattern to emerge at +240 for example and if so then claim you have spotted something?, if this is the case then you cannot really claim any credit for this because the supercomputer is doing the forecast for you. What would be more impressive is to spot something when the GFS is all over the place at this timeframe.
In my experience, those who shout loudest about their supposed wealth of knowledge are often the very same people who lack a true understanding in that subject.I can relate to this. When I first joined this forum I admit I was rather cocky, arrogant, loud, brash and thought I knew more than I did. In time I have realised my knowledge is nowhere near some on here hence my lower profile these days.
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No, I've always been consistent about that. The Met Office describe their NAO forecast as "experimental" and I class all and every long range winter forecast as little better than a guess at this range. The stats prove it. I've also always supported the Met Office, but no matter how much expertise and experience goes into their long-range forecasting, it is still far from being reliable. In the UK, they are the best, because of their experience and expertise; but their best does not produce anything approaching a good percentage success rate.
Silly? Nah. <_<
Paul
Im not talking about how reliable their forecast's are my point was in reference to your comment about them not taking into account GW when producing their LRF. I still maintain this was not just silly but a stupid comment.
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For me, frozen, they are the best in the world and the most experienced, in forecasting our weather in the UK. Pound for pound, over the years, I feel they have been better than the American agencies and they still are.
No-one's perfect, but UKMO do us proud, for a large percentage of the time.
Paul
Im a little confused Dawlish because on the one hand you say the above, and yet on one of your earlier post's you question if the Met O take into account GW when producing a LRF!. This TBH honest is a silly statement especially when you take into account the experience & expertise that goes into their LRF's and all the data they use to come to these conclusions.
Even though the Met O LRF is a little vague I would much prefer an honest forecast than a wrong one. Im sure as time progresses the Met O with firm up the details of this coming winter as more data comes in.
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Those charts not only show how different the synoptics generally are in the 'even larger teapot', but also show the marked difference of temperatures in the Arctic. The 16th February 1979 chart shows 850hPa temperatures in the Arctic circle below -25°C over a huge area:
http://www.wetterzentrale.de/archive/ra/19...00219790216.gif
Compare that to charts we get these days and it shows a marked difference:
2006: http://www.wetterzentrale.de/archive/ra/20...00220060216.gif
2005: http://www.wetterzentrale.de/archive/ra/20...00220050216.gif
2004: http://www.wetterzentrale.de/archive/ra/20...00220040216.gif
2003: http://www.wetterzentrale.de/archive/ra/20...00220030216.gif
2002: http://www.wetterzentrale.de/archive/ra/20...00220020216.gif
2001: http://www.wetterzentrale.de/archive/ra/20...00220010216.gif
Now obviously this is just one day during an entire winter, but the absence of pinks and purples compared to 'older' charts only makes the likelihood of the UK getting a proper cold and snowy spell all the less. If an airmass at the source is 5°C warmer, then after moderation it will be 5°C warmer over the UK aswell. Such differences in temperatures can make the difference between rain and snow in some cases. The big question though is whether a warmer Arctic is a result of synoptics pumping warmer air up there, or whether the airmass temperatures are a result of a warming world, which in turn drives these synoptics.
Hang on though PIT if you going to post archive charts with recent one's then you have to post like with like.
Look at the 500hpa link's below for 79/05 on 16th Feb.
http://www.wetterzentrale.de/archive/ra/20...00120050216.gif
http://www.wetterzentrale.de/archive/ra/19...00119790216.gif
Completely different synoptics and I bet if I looked at the archive chart's I could find simliar 850 temps to those of recent years. I hate the term even larger teapot because to me if we get the combination of right synoptics with cold pooling then winter's of the past can still occur. Last winter was a good example because Russia had a spell of intense cold and if synoptics could of bought that cold pooling our way then a big freeze would of occured. Too many people just assume that if an E,ly come's our way then ice day's are a certainity and if they don't then GW is to blame without looking at the larger picture. The synoptics over Europe are equally important as the synoptics that bring our cold spells. For example if Europe had experienced a spell of SW,lys and then we have an E,ly this isn't going to be as cold than if Europe had experienced a spell of N,lys. This is why I never understand why people get excited at cold pooling occuring over Europe in November because being a continent the different airmasses can bring an abrupt change in temperature and this can swing very quickly from mild to very cold. The problem recently is whenever we have had an E,ly the conditions in Europe weren't ideal for a very cold spell due to the synoptics prior to our E,ly. Let's hope this winter we can get the combination of cold pooling and then the synoptics.
Just remembered that last Dec we had a max temp of only -4C which would of been classed as very cold in even the good ol days.
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However, overall, I think everyones opinion is speculation frankly, and I would rather wait and see what happens for a while and be more open-minded about outcomes - rather than adopt a cut and dried 'I know exactly what will happen' attitude to all this warming debate.
Or perhaps rather more accurately, I would suggest some being far less certain about what will not happen! For me the period of 'proof' is still embryonic. Let me put it this way - as humans, if we are careless enough to kick-start GW then who are we to start being cock-sure about its effects weatherwise,temperature-wise et al?
And August turned out a fair bit cooler than I predicted! B)
Tamara
I couldn't agree anymore with the above SP.
My view is simple anyone who has the "I know exactly what will happen" attitude is either extremely arrogant or extremely stupid IMO.
We have enough trouble prediciting what will occur in a week's time let alone our future climate and nobody has enough knowledge to know how GW will affect our weather patterns. I remember back in the 90's when a series of Atlantic storms caused havoc in the UK, I remember the media going over the top saying how these will become more frequent and severe over forthcoming Autumns/Winters and yet who would of expected such a quiet Atlantic these past 18months!. It is this uncertainity in our climate why come November I get excited at the prospect of winter because yes our winter's are warmer than back in the good old days but it would only be a fool who would totally write off the chances of a cold winter.
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Steve
It has been my belief and I stand up as one of the 'callers' that we went through a longterm synoptic change in 2005. I will say there are not many who called it, indeed single figures. This is not look at me I got it right because it still may be a blip but it is becoming a big blip with more interest in sight with extra polar cooling. Now regarding this I stated that the arctic warming has been much more to do with synoptics and ocean temps rather than anything else. This cold pool we are seeing IMO is possibly a knock on effect of the synoptic change AND the finding that the oceans have lost 30% of their heat since 2003...and this heat has not been stored in the atmosphere...it has gone!
I do not think we are in a blip.
Reading the posts I believe you like the look of things
BFTP
You know what has cause this pattern change don't you?.
Ever since I joined this forum back in Oct 2004 I have forecasted nothing but E,lys and strangely enough that is exactly what happened in Feb 2005. So nature has finally given in to my demands and given me what I want.
Who need's science when im around
.Seriously though I did make a post about synoptic change back in March 2005 if anyone remembers
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It is indeed too early to get over excited by anything - but, if the jet can remain near our latitude then although it means having to put up with rain and atlantic winds the 'pain' could be a good thing for the longer term and allow this early cold pooling to remain intact and grow further - ready to strike when it matters in the months down the line. It does not matter in the short-medium term about us being on the wrong side of the jet if the arctic, Greenland and other northern areas are not swamped with sub-tropical air and these colder conditions are allowed to consolidate and intensify progressively. A vigourous thermal gradient inducing some beefy lows may ironically be seen as a good sign for colder than usual conditions to the north providing a greater contrast of air masses than we have seen in recent autumns and as long as the jet does not kick too far north, aka GIN corridor pattern, then good things may eventually follow.
I can see many fretting over a westerly autumn and early winter - but this may be worth 'enduring' for much better things by the end of the year/start of next as the jet lowers further and the polar front descends the country.
I will get shot for saying something like this but remember how stormy and unsettled Dec 78 was --- and what followed
Tamara
Your quiet right SP and 1981 is another good example. All 3 Autumn month's were extremely unsettled with even an outbreak of Tornado's in November and yet both Dec/Early Jan 82 were extremely cold & wintry with some record breaking min temps.
Autumn and Winter discussion...
in Spring Weather Discussion
Posted
A very good idea :lol: .
My main point im making about August is that for my location it wouldn't of mattered if the temps were +25C it was a very dull/wet month and very disappointing.