[Winter 2022-23 : Forecasts and Discussions]

On 26/11/2022 at 21:18, SqueakheartLW said:

Mild Novembers vs following winter

As it appears November 2022 is going to definitely end up milder than average provisionally and certainly with the final CET mean figures I thought I would do a bit of research on this one and see how winters panned out following mild Novembers in the past.

I have used all Novembers from 1870 to 2021 so I can include ENSO status within them too and the criteria for a mild November is a CET anomaly of at least +1C above the relevant year's climatological mean.

Using this I ended up with the following 33 years between 1870 and 2022

As you can see all years have November CET anomalies of at least +1C above the 30 year mean mentioned just to the right of these. The individual monthly winter CET's and anomalies are in the middle section with the section on the right containing the CET monthly means for those 30 year means. The far right is the ENSO status for that period between the November and March period.

All mild Novembers vs following winters

First I simply averaged out all of the anomalies for each month as well as all anomalies to get the overall December to March anomaly and put these next to the most recent 1991-2020 mean and came up with a projected monthly CET figure based on these. The result is below.

Using all these years it looks quite promising if you are after a colder than average winter, particularly later on in the winter.

December is slightly above average but not by much and in fact comes in as green for basically average with a projected CET mean of 5.14C so still potential for colder weather mixed in with milder cancelling each other out.

January is where the interest for cold begins to increase as we head below average with the anomaly by a small amount, enough to take the mean projected CET slightly below average at 4.36C. Not too bad and based on the results the cold is more likely later in the month than earlier.

February is the most interesting from a colder perspective with a more solidly below average mean predicted with a colder than average anomaly giving a projected mean CET of 4.18C.

March sees a recovery back to close to average again at 6.60C but this is still slightly on the colder side of average.

Overall a signal for a slightly colder than average December to March period at 5.07C with the most cold potential in February.

All mild Novembers in La Nina or ENSO Neutral years vs following winters

This is where things get much more relevant to this year as we currently are in La Nina conditions and these are predicted to move back to ENSO Neutral during the winter so I have included the ENSO Neutral years with the La Nina ones. A reduced total of 18 years were left. These years are below.

Now we will see how removing all the El Nino years changes the overall results.

If the initial all mild Novembers vs following winters looked good for cold prospects then this one looks even better as now all months come out colder than average, even the Decembers.

Decembers now come out with an anomaly of -0.21C compared with the +0.17C from before which adjusts the projected December CET down from 5.14C to 4.76C and now looks a bit more promising for colder potential.

Januaries are now more solidly colder than average with a new anomaly of -0.69C compared with the -0.30C from before which adjusts the projected January CET down from 4.36C to 3.97C, bring it on.

Februaries look even better than before and a definite bet for a good cold month with a new anomaly of -1.26C compared with the -0.71C from before which adjusts the projected February CET down from 4.18C to 3.63C and makes it the coldest of the 3 main winter months.

Marchs have also adjusted colder but only very slightly and still come out basically average with a new anomaly of -0.17C compared with the -0.14C from before. This only changes the projected March CET down from 6.60C to 6.57C.

Overall for the December to March period we see a new anomaly of -0.58C compared with the -0.25C from before taking the overall period CET down from 5.07C to 4.74C.

Conclusions

Overall it would seem that having a mild November is a good signal for a colder winter to come and heavily favours a back loaded winter. Also it would seem if this happens in a year that isn't an EL Nino the prospects are even better. It would seem using this measure for 2022 looks very promising for cold for winter 2022/23, what could possibly go wrong ........... ???

Well everything probably knowing the weather in the UK but we can hold onto hope that this mild November vs cold winter to come theory holds true. Watch this space in February in particular.

Hi @SqueakheartLW,

Thanks for the info. Apologies if I have missed something but you mention "the criteria for a mild November is a CET anomaly of at least +1C above the relevant year's climatological mean", wouldn't it need to be higher than standard deviation to be an anomaly and not higher than the mean ?

Also, are you extrapolating from comparisons with other years where November temps were similar that the overall winter outcome should likewise be similar ? wouldn't using one variable, the November temp similarities make this a weak analogue for this year ? I would have thought a good analogue would include lots of variables. I am not a weather person so totally clueless in that sense but in another sense we are mathematically modelling a complex phenomena with lots of variables, where each interaction between variable may have more or less significance than other variable interactions so I would expect there isnt much that can be extrapolated from the data ?

Excuse me if I am taking it too literally (Autistic), I just often see people look for past years and how they compare but in a math sense this only really works if you have something that compares on all the levels we measure, and when we understand all of the variables and their interactions. I don't expect we ever will know all the variables and their precise interactions when it comes to weather so I understand a statistical comparison with past years can be helpful in finding a good or reasonable analogue but I would have expected more variables to be compared at a minimum

 

[Stratosphere and Polar Vortex Watch]

19 hours ago, Don said:

I think the fact of the matter is we are likely to see another mild January. 

Not sure how you can jump to that extreme a conclusion, the models are not great at all at forecasting more than a week ahead. However, despite no SSW we still had substantial cold in December and already here in South Wales we are well below average temps again for a few days. In December we spent about two weeks with sub zero temps, now considering Met Office data shows average low through Jan and Feb for much of the UK (including here) is only zero degrees, our -9 was substantially below usual temps, and as colder here than it was in 2010, although not as cold for as long we still had two weeks of -2 and -3 with wind chills much lower which is again for December well below even the Jan and Feb average lows. Snow was good, not as good as 08, 09 and 2010 but was near a foot at about 200m which lasted days.

Today it will be down to -2 and tomorrow about -3 (forecasts keep changing), so we don't need an SSW event to get cold and snow, considering we had all that before winter technically started on 21st of December we still have plenty of time and as I said, as for the models they ain't got nothing nailed for more than 5 or 7 days so January is far from written off.

[Winter 2013-2014 Discussion- Part 2]

HI Maw,Thanks for the great post, clearly a lot of time and effort put into it..I completely agree with you not to judge a book by its cover, except if we were talking about `he whom shall not be named`i did wonder about piers methology though as you say , he is touting a big storm for the BI come new years day, give or take a couple of days either side.Piers Corbynâ€@Piers_Corbyn1hRtRt! BEWARE MAJOR NEW YEARS DAY STORMS B+I+Eu, USA; as SOLAR ACTION UPS http://bit.ly/1eeJIsw <=WHY THE STORMS? http://twitpic.com/dqdjlr Ty so looking at the models for new years day shows a shallow trough approaching from the west, which at best/or worst depending on your POV will give a wet day and a bit of a breeze for the south east...thats from the gfs 06z , maybe it wont be there on the 12z or it gets a bit of an upgrade..then theres a big storm over usa to yet develop and clash with some very cold air being ejected into the atlantic.. as Noaa have used a new word apparently to describe it `bombogenesis` . so real potential for a big storm to brew and head our way, maybe by the 6th according to gfs...whereas ecm not as progressive.so thats 4 days out of his window of time...albeit there is a lot of solar activity at the moment (cme`s i think) is this something he predicted/forecast 4 weeks ago.

Is it not a prettt decent storm today? Within the 2 day period. Forecasted over 4 weeks ahead. Impressive. I know people dont want to derail thread but the detail of the forecast is to accurate and to frequent to be chance. Give credit where credit is due I say

[Winter 2013-2014 Discussion- Part 2]

is piers corbyn`s  metholdgy anything to go by ?

Hi Bryan.I personally think he is the best forecaster I have encountered. People are too quick to dismiss him, often because they have just believed what others have said without looking for themselves, because people get into clicks and dislike anyone outside of their little cozy groups, because people dislike any competition despite credibility etc.For example, someone here answered you with a NO, he is not credible, despite admitting not even following his work, or most likely not ever having purchased his forecast and not honestly knowing what Piers has forecast, which is very common, people believe what they hear, don't bother seeing his forecasts especially as they have to be bought and just speculate... which is very very unscientific. How can you say he is bad or got things wrong if you never bought his forecast to start with. Thats just you lying.Piers is well qualified for a start, unlike many on weather forums who do love to speculate and assume, while Piers follows strict scientific methodology, which unless coming from a science background, you often wont understand what these strict processes are and why they are important. Piers is gaining some serious reputation around the world, he is getting recognised by large organisations, governments, and political figures. He is probably the most recognised weather forecaster outside of organisations like the MO at the moment, that you will come across. How many guys here have been invited to parliament to discuss weather with government? How many here has been invited to other countries to talk weather with their governments?If you guys want any credibility in this field of science that you are discussing, then don't ignorantly ridicule another scientist before learning his methods and, actually seeing his forecasts, while giving him a sensible enough amount of time to see if there is any reasonable success.Here is a few examples of my experience with Piers. 4 weeks ahead he forecast a red warning for snow in my town. Met office picked it up 5 days ahead, but they chopped and changed wildly in their predictions, going from a yellow warning to amber and finally a red warning the evening before the supposed snow event. Piers doesn't only make a 4 week ahead prediction but he doesn't chop and change (which isn't really a prediction if you chop and change as you would be making a new prediction each time). Despite him predicting it 4 weeks ahead without change or update, he was impressively... correct!

 

This pattern has been the case over the last 2 years that I have followed him. He does make mistakes but they are blown out of proportion by the ignorant, because every forecaster gets it wrong, but I think people are jealous of Piers amazing success and make a larger deal than they ought to. He forecasted a storm this year with damaging winds, low pressure system, sweeping across parts of the UK, 4 weeks before, while the Met O had not a single signal of such event a week before, so accurate he was that his followers called it Piers Corbyn storm in credit to his success.One such example you could use to check out his ability is the storm that he has forecast for new year which had not been recognised by the Met O and many others over the previous 4 weeks. Piers does give a 2 day variability on his forecasts, 2 days before or after the said dates but that is entirely understandable considering Piers is forecasting a lot of highly variable bits of data over an incredibly long period of time. So Piers has another bad storm with 90+ mph winds hitting parts of the UK between tommorrow and the 2nd of January. If he gets it right again, another significant event to add to the list that he forecast weeks ahead while many model watchers were still guessing at what's the weather going to be next week, because that' about as far ahead you can get any reliability from these models. Even then they are wrong far to frequently.

[Snow and Ice in the Northern Hemisphere 2013/14]

Please do so, should you wish. I must say 2009 looked pretty poor for snow and ice when I viewed it, but January 2010 was a very cold one and a decent December preceded it. It's similar to overanalysing each and every model run, you take what you take from it all I guess.

 

That is exactly why forecasting by comparing similarities is useless. Just because two things look the same over two periods, doesn't mean the causes were the same, and while it can appear to be accurate from looking at the most statistical outcome quite often, it's not a genuine understanding or a good method for forecasting as there will always be years that won't be average and unless you know all the causes and how each cause interacts with all the others, then people will keep getting caught out making forecasts based on cosmetical similarities. I As highlighted, no doubt there will be good winters here while being low amounts of ice and snow in the NH. Could mean that ice and snow coverage has little importance for our winters, or just another cause has more influence than the snow and ice, like an SSW for example. Sorry for stating the obvious, but I find it fascinating how many people interested in a mathematical and scientific forum, using such unreliable assumptions purely on similarities.B F Skinner did some interesting Pigeon experiments that highight how people learn these superstitious beliefs. The pigeons were conditioned to do bodily movements to get rewards, just as you would train a dog to sit with a treat t reinforce the behaviour. All animals including people learn the same way, we are pattern recognising machines. But Skinner observed ther behaviours, when he released food at a fixed interval and not as a reward for the pigeon doing a particular motion the pigeon was still looking for the pattern, so it would remember the last movement it made when the food was released and would repeat it, then when the next piece of food was released the pigeon would remember what it was doing that time and keep doing that mve hoping to earn a treat and after a period of time Skinners pigeons were walking around doing all sorts of unnatural movements believing superstitiously that it made a difference, when in fact it did not, food was released at a fixed intervals.A bit long winded but this is exactly what I see people doing with the weather all the time, unless there is specific scientific reasoning that can be directly linked, observed and repeated to prove the theory works, then it is most likely a superstition formed by observing a pattern that seems to exist, but does not. If you find a number of years that contradict the notion of NH ice and snow coverage having any significant infuence on our weather, then it is either a superstition or it isn't influential enough to matter as it is often being over ruled by more powerful weather factors.

[Winter 2013-2014 Discussion- Part 2]

Plenty of snow in South Wales this morning and into mid day, stuck on high level roads and a few cars have gone down banks after leaving snowy roads.I don't know why people say years that are similar to this have ended up badly, sorry but weather is chaotic and doesn't work like that. 2 very similar years could have very different causes, or even a number of different causes so comparisons like that are very unscientific, illogical and not even good mathematically, sounds kinda pointless to compare years. Although, people are far more confident on other threads like interesting activity on the SSW front and good ice and snow coverage in the NH.Plus, here in South Wales it has been hitting below average for the last week and looks to continue as far as the models are any reliable at predicting with any accuracey. Considering it's colder than average and snow as far as South Wales and it's only Mid November I think there is lots to be positive about. I think the problem on this thread is a lot of negative people commenting. Where as there are many of positive people regarding winter also. To be frank trying to predict the whole of winter this far out is pretty daft. But while people here are comparing this year with others that have gone poor snow and cold wise is quite hilarious because in the snow and ice thread and the SSW thread the majority of people talking are comparing this year with the likes of winter 2009 and 2010, goes to show there is no solid proof or concenus either way, but as its cold and snowy around the UK in November and the sun is very inactive, I think it's a good time to be positive.

[Winter 2013/2014 Forecasts/Hopes/Discussion Thread]

Personally I don't care when, as long as it comes. Preferably cooold!, prolonged and deep snow with some howling winds that carries away the sound of your voice into the whiteout. Some shocking drifts from the bliazzardy conditions. As long as I can get all that, I don't care when it comes, I will be ready... same as I am every year, winter gear just sitting there in it's place ever year just waiting for some good snow conditions. Of course I will settle for less and always make the most of what I get, even if it means having to romp all over the mountains to find the better stuff. But I'm waiting every year for that big one.

[Stratosphere Temperature Watch 2013/2014]

thanks chio for the reply. From what i here solar activity is on the rise would that have any effect on the strat down the line? If i'm rite last dec's cold was scuppered by that according to gp. Shame wouldn't get his input this winter.

Is it really on the rise? from what I have seen it was in decline. The CM Predicts a rise while the SC predicts a drop but I don't think anyone can say for certain.http://sidc.oma.be/sunspot-index-graphics/wolfjmms.php

[Winter Model Discussion 12Z 09/01/13> The hunt for cold ?]

Dave, the GFS has churned out 4 runs today all showing the same outcome with that shortwave.

Many members of the forum will not have been around for many past failures and will struggle to understand why 1 model, out of maybe 4 or 5, turns out to be correct when showing mild, so they need to be prepared for the possibility of the GFS being correct. I think you probably know yourself Dave which way it will go. Fingers crossed it doesn't because the GFS at T168, well, will take care of the next 7-10 days with that pattern.

But you seem to be missing the masses of criticism towards the GFS in previous posts... it appears not to be processing the situation well and it's current position may deserve serious doubts. Again though as Dave pointed out, some of us coldies are prepares to be open minded and despite the almost unanimous support that the GFS may be right.

[Winter Model Discussion 12Z 09/01/13> The hunt for cold ?]

You've over complicated what I stated I was pointing to the scenarios painted by the GFS, ECM and UKMO. Just those three. One of them is likely to be accurate. They are all very different. One is a very cold and wintry east or North easterly, One is a slack northerly and dry for many. One is a mild and dryish south westerly. If you toss a three sided pyramid it can only land on one side, and it has a 33.3% chance of landing on that side. In the same way, two of the outputs are likely to be quite wrong compared to the eventual outcome. Most modern day output us formulated using Math and percentage variables.

I have no doubt over complicated your statement, I have a habit of doing that. I mean no offense but I still disagree with your analogy. You can't compare the three scenarios with that of a 3 sides pyramid as again the three sides have equal values so the odds are an equal split.

But the three scenarios are not simply a choice between 3 equally likely scenarios but scenarios based on the accuracy of the chart. If one chart has a different source of information, different observations or different input then it would change it's value as well as their rates of accuracy would give them different values. So there is not 1 in 3 chance. I understand in simple terms we have 1 of 3 scenarios, but the odds on each scenario are not 1 in 3. We have 3 scenarios that could have 70% against 20% or 10% for example.

[Winter Model Discussion 12Z 09/01/13> The hunt for cold ?]

Exactly and if you factor in the GFS mild output, technically the ECM has a one in three chance of being correct, or a 66% chance

of being wrong. Lets see what the pub run serves up in an hour or so.

Technically that is incorrect. You have assumed all three are equally accurate or successful. If they all had 20% success rate (random figure) then yes you could argue that they would have equal values which would allow a clean division of 100% by 3 but they not only have different success rates but their success rates seem to vary which would mess up your estimation even more, do we know at present what success rate the ECM and the GFS has etc.

Your 100% probability could actually be made up of 70%, 20% and 10% split rather than 3 equal parts (random figures). I wouldn't like to hazard a guess to what odds there are the ECM will be right, however there is a lot more support from ensembles and models in favour of ECM than there is GFS and this would give a boost to the odds in favour of the ECM.

I am assuming you were serious when you said technically it has 1 in 3 chances of being right, maybe you weren't I don't know but I thought I would like to point out for any people new to the charts that it isn't a correct observation of the odds.

[Stratosphere Temperature Watch 2012/2013]

@John Badrick, There hasn't been any increase in activity on the sun. The sun as of today is still at low level activity as it has been in quite some time. There are sunspots visible on the disc but non of them are magnetically complex at this time. Check SolarHam website for reliable up to date information on solar activity:

www.solarham.net

The current activity is still in a nose dive as can be seen in the graph updated by Nasa this week. They have been forced to reduce their cycle count prediction after increasing it to 72 a few months back:

http://solarscience....v/predict.shtml