Ruzzi
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Posts posted by Ruzzi
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4 minutes ago, mountain shadow said:The GEFS?
Is that the GEFS, where every single ensemble member predicted a proper cold spell around Christmas, which spectacularly failed?
If you're going to try and prove a point, I wouldn't be using the GEFS for it.
In all my years on here I have seen a few predicted cold spells disappear, but I have never seen a predicted PV dominant spell disappear .
That is why I'm confident of no proper cold before month end.
And equally if you're going to write off a full month on the 4th.... Don't base it on a day 10 chart of one ECM run which is what you based your point on.
Day 10 ECM charts aren't exactly renowned for being on the money either.
January is not written off, irrespective of what any output is showing.... Its the 4th!!
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7 minutes ago, alexisj9 said:
Thing is we don't need one, trop and strat are not together, which is normally what we need a SSW for, it changes the trop, and then moves down to the strat, right now that connection is not there, might even be that an SSW does nothing at all to the strat, in this scenario, something is different this year.
Yeah I'm still pinning my hopes on a Sudden Tropospheric Warming.
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58 minutes ago, Updated_Weather said:
Yeah we have been in a favourable conditions before Xmas regarding MJO etc.. look what happened. Had no effect on us at all.
just my opinion.. we will see how it plays out.
You just completely contradicted your argument.... January is out the window cause the background drivers don't support it?.... But then say that the background drivers were favourable last month, and it didn't lead to what was possible/expected..... Surely that in itself is enough to sit back and think that on the 1st of the month, anything is possible, irrespective of what the background drivers show.
Also I note you mentioned as part of your back-up that no SSW is expected in January.... even if there was, it most likely wouldn't effect the weather in January unless if was already underway given the potential lag times, albeit there can be a quick trop response but it really would need to be getting underway about now so whether a SSW was or was not forecast for January, it really would be unlikely to have much bearing on our January weather unless you're thinking about SSW precursor patterns as part of your argument? Or a SSW happening right now with a short lag to affect the latter stages of january?
I genuinely am interested to know what background drivers you are referring to for your January outlook. Not trying to be snide, I'm just curious?
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4 hours ago, syed2878 said:It’s very interesting how this issue with warm Septembers and mild UK winters have come about I have not heard about this until this year when I was watching Gav whether vids this winter update that he does and he did bring up the subject. He did show few years that had a warm September which was followed by mild winters how ever I think it’s the exhaust height that killing our winter chances those highs have been quite stubborn over the last few years. As for the SSW we had quite a major one last year if I remember correctly that did fail to deliver and that is no sign in any models at the moment of an SSW occurring.
Maybe more of a subjective issue with regards to last year's SSW delivering or not because I ended up with this: 47cm of level snow and drifts a plenty...
In terms of this year, the strat is not my strongest subject but with there being a complete disconnect between the strat and trop, I'm really not sure how a SSW would affect things.
With the uncoupled trop and strat set to continue then I think there's plenty of options going forward however with the strength of the strat at present, what we really don't want is a solid coupling if there is not to be a SSW.
I genuinely have no idea what would play out if we were to get a SSW while there remains a disconnect between the 2.
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16 minutes ago, North-Easterly Blast said:
Regarding cases of warm Septembers leading to cold winters; I can only think of cases where September was slightly above average (14.2) rather than particularly warm, like 1978 and 2009, where a cold winter has followed. The warmest September that I can think of that has led to a good winter for cold was 1985 (14.6). I cannot think of a September above a CET of 14.6 that has led to a good winter for cold.
I don't want to labour this point otherwise I'll have a Mod fist shaped mark planted on my dish...
But I don't think anyone is disputing the figures for CET for the months that are there, and the winter CET following a particular September CET, the point is that no direct correlation or explanation can be made between solely the September temperature and the following winter.
Anyway big overnight runs coming up why not eh
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1 minute ago, weathercold said:
We had so much lining up in our favour a few weeks ago, quite amazing how quickly this changes.
I wholeheartedly agree with many in that IF we fail (likely in my opinion) to pull out a deep freeze this winter with so many drivers on our side it does raise the question- due to global warming impacts do we need to be realistic that a cold spell (5 days plus temps close to freezing nationwide) really is a thing of the past? I’m increasingly thinking it is sadly.
No.... No it most certainly isn't.
Winters of the 1700's, yes maybe so but a 5 day cold spell with temps close to freezing across the country..... That most certainly is and will be for anyone on this forum, a possibility during any winter
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1 minute ago, sundog said:
Not so. Going into this winter there were some like myself who were concerned about that very warm September. In recent decades it very rarely bodes well if its a decent winter for cold you want . Granted there's still much of the winter yet to go,but I'm not particularly optimistic. What the models were showing before Xmas and the possible cold spell, i thought maybe we might get away with it this winter after all. Well that possible spell imploded but anyway we will see what happens over the coming 2 months.........
I could have maybe understood if it were down to particular teleconnections or, even if someone had mentioned reduced snow cover in the northern hemisphere, QBO phase, enso state..... But come on, becuase the UK had a warm September? 2 months before winter starts?
Sorry but I'm not entertaining that, a warm September could have been caused by so many different synoptic evolutions. A simple factor of temperature in September cannot have a bearing on the following full winter.
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17 minutes ago, North-Easterly Blast said:I think it is the warm September theory striking again. It appears to be a well known fact of the British climate that it is very rare if not unheard of to get a cold winter after a significantly warm September. I always think that a warm September is bad news if you like a cold winter. Mostly after a warm September the following winter is mild - or at best close to average (2005-06, 2014-15). Whilst it does not appear that a cool or average September increases the chances of a particular type of winter to follow, the theory appears to work that after a warm September the chance of a cold winter is very slim indeed. So the fact that we are faced with what we have now is testing the warm September / mild winter theory again.
11 minutes ago, Don said:Yes, the warm September was a big concern for the winter.
Please tell me that this is tongue-in-cheek?
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23 minutes ago, DCee said:
Just because there is 'scatter' in the ensembles post day 5 doesn't always mean there are cold options and doesn't necessarily mean there is uncertainty.
Alot of the scatter is actually the same theme as the op but just out of phase, so same weather just offset in time from the op, sometime by hours sometimes by days.
This is what is being modelled now, so it's fairly certain all the way out to two weeks....despite the scatter.
Of course things do pop-up from time to time...so nothing is nailed at day 14 for sure.
I think you've made a mistake when you suggested i predicted mild for two weeks. I did not. I said for the foreseeable, which is the now and the days ahead.
Sorry I wasn't directly quoting you, the 2 week reference was not taken from anything you said, it was mentioned elsewhere.
I don't however agree that the weather is certain, or even fairly certain out to 2 weeks. There were points not so long ago where it seemed "fairly certain" that we were facing a cold foreseeable and it changed very quickly.
And whilst I understand your point about about the ensembles showing the same pattern, just delayed by time... It's just simply not true! Especially when you're basing it on an 850's temperature basis. An ensemble could show a very similar temperature 850's wise as another ensemble member, but have a completely different synoptic pressure pattern to each other both in our locale and hemispherically.... So if you then add in the fact that by day 5/6 that there is a developing scatter, there can only be uncertainty from that point forwards. For example, if you take all the ensembles at day 6 as a starting point, and run them for the 8 days from there (which takes you up to the end of the 2 week period that you're stating is fairly certain in terms of outcome) .... There is absolutely no way that they will be showing the same general evolutions only delayed by time.
There is nothing simple about weather or indeed predicting weather as I'm sure we're all aware, but one thing that is absolutely certain is that when ensembles show scatter, especially as much as they are showing just now, you cannot be certain of a course of weather type or indeed how the following couple of weeks will play out.
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16 minutes ago, chapmanslade said:
But that was not what you said!
The standard deviation does increase significantly by day 5 or 6 suggesting uncertainty, although there is ensemble support for the OP run and the sudden drop in temperatures. But the op is not an 'outlier' and nor does it indicate 'mild for the foreseeable' future. In fact a transient N does seem likely.
Absolutely, it is not an outlier whatsoever!
Sometimes I feel like people latch onto terminology and spout it out at random times for literally no reason at all.
I think the conclusion that can be drawn from that particular run is that there is huge uncertainty beyond the 3rd of January. There's such a large spread across all the ensembles from the 3rd onwards that there is no clear specific direction of travel that can be drawn.... Which we already knew prior to the run anyway
The op goes from bottom of the pack, to top of the pack at various stages, huge scatter = more time and runs required, especially given that the deviation starts from day 5/6, in times of such model uncertainty, it's always going to be FI at that point anyway.
Watching brief would be the order of the day, see how the next couple of days develop, looking for recurring themes and patterns and as the divergence point of today's runs draw closer over the next couple of days, it'll hopefully show the direction of travel moving into the early stages of January.
And, finally... Looking mild for the next couple of weeks it ain't!! That's not to say it won't transpire like that, but taking an overview of all the models, and the many uncertainties at this point, there is no consistent signal for mild weather through-out, the next few days yes absolutely, but from day 5/6 onwards, there's no solid indication of a continuing mild theme....
Scatter = uncertainty
Plenty of options on the table, cold and mild! Let's see how we fair over the next couple of days but enough to keep the interest for sure!
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New thread to start the next chase then?
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UKV pepping up the North Sea activity.... We're not talking beast style convective heaven, but still good to see some showers appearing and drifting inland a little at parts on Xmas night and into boxing day.
Having said all that..... The way the models are, I'm still not confident on what's going to happen on Xmas yet with the constant changes and adjustments.
I really can't help but get the feeling that the southward corrections are going continue right up to the day its happening. Seen it so many times where the front was initially shown in Scotland only for it to miss the South altogether come the day.
The southward corrections obviously have ramifications for us as well.
Curious to see if we land a bit of snow tomorrow before it turns to rain aswell
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12 minutes ago, nick sussex said:
Winter is Dec Jan and Feb . This 21st thing seems to be an import from the USA.
All stats regarding winter include just those months .
Fair enough so on that basis then as of today we hit the 3 week mark, with 10 weeks left til the end of February however with the greatest respect, people aren't here because they're only interested in stats and how they panned out culminating on the 28th of February and nothing afterwards.... If its shows a foot of snow on the 2nd of March, it'll make no difference to people whether it's within the so called defined winter months.
My point was that there is scope for wintry weather or snow or cold spells etc for another 14 weeks or so, and trying to write that off on the 21st of decemeber and only referring to 2 factors as a basis is a frustratingly inaccurate read.
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8 hours ago, Met4Cast said:
EPS on the 18th..
EPS today
If that isn't a substantial shift away from colder solutions then I don't know what is. All models have handled this incredibly poorly, falling AAM and a waning MJO signal into January is making this late Dec cold a bit "all or nothing", the signal for something more westerly Jan/Feb is growing.Personally this is looking like nothing more than a bog standard cold spell now, a few lucky spots in the north should do quite well but if you're in the south its looking very meh, no matter how many ENS members you pluck out.
Someone posted a picture of straws earlier, hope you've still got em handy
I know you dont want to be considered as just a 'random person on the Internet' and I see the work you put into your pages and posts on here etc.... But please don't start banging that drum online, you don't want 85% of people in the Peak left thinking the whole winter is over now
P.S....today is the first... Yes the FIRST day of meteorological winter. I know you only quoted Jan/Feb (however March can deliver the goods aswell)... But there's 10 weeks!!! til the end of February, plus the whole of March to come. That's nearly 2 and a half months, plus March on top.
Winter is not over just because it may not snow on Xmas day and referring to only 2 factors in order to put the rest of winter to bed is beyond me. Especially when it's 2 factors that can change quickly.... We're not talking about long term slow moving factors that you mentioned like LA nina, or QBO or solar cycle etc.. Honestly it's the 21st of December!!!!
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15 minutes ago, Cold Winter Night said:
York far enough North? Same story unfortunately.
You're still in the southern half of the mainland by a fair distance, so no probably not quite. About 250/270 miles between York and Brighton on the south coast, and about 440/450 between York and Thurso on the North Coast
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Awww go on thennnn, geez the GFS
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7 minutes ago, weathercold said:
Possibly, but we need a fast turnaround especially for those in the south.
still time but we are reaching last chance saloon here I thinkLast chance saloon for what?
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14 hours ago, A Winter's Tale said:Some similarities with the cold spell of late December 2000:
21 Dec 2000
21 Dec 2021
22 Dec 2000
22 Dec 2021
23 Dec 2000
23 Dec 2021
24 Dec 2000
24 Dec 2021
25 Dec 2000
25 Dec 2021
26 Dec 2000
26 Dec 2021
27 Dec 2000
27 Dec 2021
That cold spell started around Christmas Eve and lasted to around New Year’s Eve. It wasn’t as prolonged as many of the classic cold spells but it was quite a notable period of weather.
Temperatures at Glasgow airport:
24th 4/1
25th 2/-2
26th -3/-5
27th -1/-6
28th -1/-9
29th -3/-10
30th -3/-11
31st 4/-6
The period between 26th-30th Dec 2000 saw the joint most consecutive days of maximum temperatures -1C or lower (equal to Dec 2010) in records since 1973. There was quite a notable snowfall around the 28th with depths around 15-20cm+ in the Glasgow area. The weather during that period would not have looked out of place in 2010.
Looking at the archives the main difference between 2000 and 2031 is the shape of the low pressure system in the Atlantic (elongated in 2000, bowling ball in 2021).
The potential snowfall in the Christmas period also reminds me a little of 26 Feb 2001.
Well I hope you're right about the last chart because that gave me the best 24 hour snow event I've experienced.... I lived near Shotts at the time and woke up in the morning to drifts covering vans, snow to ridiculous depths and I could even walk up the drifts onto the roofs of the bungalows, truly unreal event.
I have however had better overall periods:
2009-2010 where we had about 30 days of snow on the ground, breaking up ice 4 inches thick on the road outside the house which was under a blanket of compacted snow, the Ice was literally like lifting slabs! Snow depths reaching a couple of feet at times.
November - December 2010: snowed every day for 7 days in a row whereby the level snow depth in the garden hit waist height and then a 2 day break before the infamous stalling front from the North on the 6th decemeber, cheery bye transport minister and hello M8 Arctic carpark.
March 2013 (don't recall the exact date).... An overnight period of perfect convection left over a foot of level snow and drifts but yet when I had left work in Bellshill to head home at 4am, there was barely a covering... Drove up to Newhouse and under the rail bridge towards Newmains and it was like I had drove into a different country such a localised event from memory.
Red warning period 2018: never been so excited watching charts waiting for that to hit, the 3 or 4 day period was ridiculous! Insane charts!!
And then February 2021.... Monumental 2 days here in Caldercruix, level snow hitting a foot and a half and drifts a fair bit higher. To go from nothing to the scenes that were here in the space of 2 days was unbelievable!:
Ps those tiny little black spots in the snow are the top of the 3 foot rubber bollards to mark the edge of the road
Okay so I got carried away but nice to reminisce before a potentially good spell materialising....
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Well after being the party popper, the GFS has abruptly fell into line on the 12z this afternoon, spouting this out for Xmas day itself
ECM this morning looks awesome too and UKMO probably slightly worse but not by much.
I can't deny that I'm not starting to get a little excited.... Please don't collapse
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2 minutes ago, IceDaysAndBalticNights said:Not sure there was any need for such a belittling and patronising reply as it doesn't really help us newbies such as myself understand what the models are currently showing
Its not belittling or patronising.... It was clearly light hearted humour!!!!!! !!!
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1 hour ago, Staffmoorlands said:
I don't agree. Lots has changed within the last 24hrs and its going to take some effort to get back to a cold solution now
12 hours ago, Staffmoorlands said:Nice upgrades this morning with a real risk of a cold Christmas on the cards. Temperatures falling from this Friday across the UK
So which is it?
I think given today's outputs it would tend to suggest that we are no closer to any certainty in any particular direction. All options still on the table.
Can't help but think the spike in EAMT will throw a spanner In the works soon. Still too many factors involved at present to be confident of a particular outcome.
Loving the viewing at present and the wealth of knowledge in the forum makes for great reading!
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9 minutes ago, Staffmoorlands said:
Good write up but it sounds like you are discounting the most likely option which the Met are going with i.e high moving east allowing more of an Atlantic influence as we head in to the new year.
Can I ask what makes you think that is the most likely option 3 weeks down the line?
I'll disregard the fact that you said just an hour or two ago that you don't do any long range stuff and you were only describing what the models showed within 10 day range.
The long range MetO forecast changes.... Like the weather, funnily enough. It literally flips just as quickly as any new signal gets picked up and holds for a few days. If a new signal was to be picked up say in 3 days time and it was maintained for a few days, their long range wording would change. I find it more reactive, than proactive if I'm honest. Anyway, I know MetO forecast chat is not to be dwelled upon in this thread.
I'm just curious as to your thinking that the high establishing and migrating East in around 3 weeks time is the most likely option?
My incline is that 3 weeks is far too far out to weigh up what is the most likely option at this stage. Model volatility has been very prominent of late and the MJO forecast, strat disconnect, LA nina, E-QBO and recently hinted warming in the strat would throw more unreliability in the medium to long range likliehoods that I'm finding it hard to contemplate anything beyond the 5-10 day range at most.
As cliche as it is, it seems very much up in the air for the time being but exciting to keep an overview of all the same.
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It's getting its act together here now
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25 minutes ago, Blessed Weather said:
Poor old CFS keeps getting a bashing. So in its defence, here's the thoughts of Dr. Simon Lee of Reading University, on his excellent website. Worth a read.
CFSv2 ain’t that bad: tips on using long-range forecasts
Now, every time I mention CFSv2 forecasts, someone invariably replies with “but it’s garbage beyond week 3” or “the model changes day-to-day, just guesswork”. If this is true, why have I bothered putting effort into making CFSv2 charts? The answer is that CFSv2 isn’t actually as bad as some people find it to be. Part of my PhD involves looking at the longer-range forecasts from multiple modelling centres around the world – including CFSv2 – and in what I’ve seen (some of which is in a few upcoming papers), CFSv2 doesn’t stick out as being rubbish. Far from it, in fact. That doesn’t mean it’s the best — it isn’t — but it’s worthwhile to look at (especially as we all have access to it), and it does quite well considering it is 9 years old.
https://simonleewx.com/2020/05/31/cfsv2-aint-that-bad-tips-on-using-long-range-forecasts/Its an interesting read for sure however as he states himself, it has huge model bias towards a weak polar vortex as the forecast time period increases.
Any model with model bias will always present its issues, such as the GFS having a bias to blow up low pressure systems etc but if you have a model bias of something as significant as lowering the strength of the polar vortex as time increases, then I can't fathom how a model forecasting a time period so far in advance, on its face value, could ever be taken seriously.
What his article explains is potentially how it could be used as something more useful, but on its face value, that far in advance, its almost useless.... I say almost, because even a broken clock is right twice a day
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Scotland Weather discussion
in Scottish Weather Discussion
Posted
If it doesn't deviate too much from that then I'll be happy. Higher parts of the central belt could do quite well by Friday morning, especially Harthill, Shotts, Salsburgh etc but sitting here at 188 ASL, I'll been checking the lamppost often.