Model output discussion - Winter has arrived

[Jason M]

1 minute ago, That ECM said:

Depends on what people are looking for. We have had “interesting” weather in parts of the uk already. People are looking for a winter wonderland and what’s more they are looking for it in 6 or so days time. The “very low confidence” from mid month is due to not knowing where the blocking and highs will go.  Is proper cold nailed? Clearly not. Is this the best chance we have had in a while? I would say so.

I personally don't see anything that points to deep cold in our part of the world and tbh have struggled to understand the high level of expectation over the last couple of weeks. That said, I completely respect that others are maybe seeing something I'm not. Interestingly, it seems that anyone who pays attention to GFS 'has no logic' or is a 'troll'. I would argue the opposite in that anyone who disregards any model completely is lacking in logic plus denigrating people with a different view is textbook trolling.  As Obi Wan Kenobi observed 'only a Sith deals in absolutes'. At the very least lets try to be respectful of differing views.

The reality is that GFS has a good level of support from its ensemble suite so it does need to be given some regard. I often disagree with IDO (especially around use of day 10 mean charts as they just tend to climatology IMHO), but on this occasion I find myself in broad agreement. As always, I want to be wrong but for me the prognosis is nothing very cold in the next 10 days (I'm tempted to say 14 days). Increasingly we are seeing more suggestions of heights to our south over Iberia as a response to the low sat in the Atlantic. Once that happens its pretty much game over for anything other than a transient PM airmass. From memory I think John Holmes came to a similar (albeit more informed) view yesterday from his charts.

Where do we go from here? The form horse would be SW / NW split, followed by UK / Euro high over Xmas period and our usual zonal new year. Just my opinion and probably wrong but hey ho.

[SMU]

@IDO Please stop going on about poxy day 7 8 & day 9 GFS when its going to be wrong at day 5 & 6.

Or at least put some reality in your posts - The GFS looks nothing like the Euros at say 5 & 6 with a split low > that means when eventually it does come round theres only 1 model that was wrong in the short term > The GFS.

These are the forecast odds from me tonight.

GFS 5% with its bowling ball low at day 5 / 6 

The rest of the 95% split down the middle of probability will lead to a cold or mild solution depending on the angle of the jet & subsequent low at 144.

ICON > COLD > Negative tilted

ECM > MILD > Positive 

UKMO > somewhere in the middle.

[chionomaniac]

Just for those that need reminding or clarifying..

 

Zonal

 

not zonal

[bluearmy]

The ecm op looks out of the spread n scandi by day 10 - that nearly always means it’s wrong. The ridge will not give way that quickly 

[northwestsnow]

2 minutes ago, bluearmy said:

The ecm op looks out of the spread n scandi by day 10 - that nearly always means it’s wrong. The ridge will not give way that quickly 

Good,this was me as EC came out this evening...

[feb1991blizzard]

3 minutes ago, chionomaniac said:

Just for those that need reminding or clarifying..

 

Zonal

 

not zonal

Agree with your post but would just say something, sometimes people do mistake a few transient ridges in between topplers for a meridional blocked pattern, they are just transient, not saying that your chart is an example of this, it isn't but some runs depict a few transient ridges in between an overall zonal pattern, my favoured way to tell is running through on meteociel NH format, if everything from Eastern seaboard to the UK is moving fast then that isn't blocking, because nothing is being blocked, blocked means a stationary wavelength pattern IMO, usually occing within a multi wavelength NH pattern.

[Jason M]

Just now, Skullzrulerz said:

It was clear as day this would happen even with the northern hemisphere profile the issue is the lack of cold air 

You don't need to be expert to figure this one out

Any postive takes?

The influence of the 'Russian' high is perfectly normal through Autumn and it often leads to a scenario where we see lots of blocky looking charts but with no cold uppers. For a good old fashioned easterly the heights need to be centered on Scandi. A ridge thrown out from the Russian high towards just leaves NW Europe under a mild airmass (at least at 850 level). The Russian high isn't necessarily a coldies friend. 

[northwestsnow]

OK so a less cold period ,possibly westerly dominated spell is pretty much nailed on.

There are appears to be  a signal for the Azores high to ridge in, the question is how favourabley the cards fall...

[stodge]

Evening all

Some thoughts on tonight's main models into mid month and beyond.

12Z GEM - model of the day yesterday but GEM flips around a lot so we'll see. The early stages this week are well set and by T+120 signs of another south-east disruption of the Atlantic trough in the face of persistent heights to the east and north east. The Azores HP negatively aligned and ridging into North Africa rather than Iberia. However, this promising evolution is quickly undone by a new and vigorous Atlantic LP formed as a result of a drop of cold air toward the eastern seaboard of the US. This new LP swings NE and re-aigns the main trough positive and drags the Azores HP up over Iberia and France introducing a much milder SW'ly air flow for the British Isles by T+216. The run ends mild or very mild with the HP centred over north Africa but dominating most of western Europe. Not quite sure the NH profile is as bad as it looks but it's not promising at this point.

12Z GFS OP - swept into the mild camp yesterday and with GEM going the same way tonight, I'm not hopeful. By T+120 one or two subtle differences with GEM. The trough is aligned less favourably but oddly enough the Scandinavian heights seem a little stronger.  By T+192, the new Atlantic feature has invigorated the original LP and it has now developed into a large slow-moving feature just off the south west of Iceland with the trough extending to the British Isles. Heights have risen to the south but not strongly at this time. By T+240 it's all getting a bit messy - shallow areas of LP form close to the British Isles as the Azores HP edges NE and the more vigorous Atlantic features stay well to the west. BY T=312, HP is dominating southern Britain but a vigorous complex LP is moving NE albeit well to the north of Iceland on what looks a strong northern arm of the jet.  The final T+384 chart has HP firmly in charge across Europe and a hint of continental air moving into southern England but the jet has too much energy to the north to allow for northern blocking at this time but the Atlantic doesn't look active to any extent. The signal for a brief but strong warming remains in FI. 

12Z ECM - it's going to need a miracle to save us from a milder spell and I don't think ECM is going to provide it. T+120 looks much closer to GEM than GFS but note the small LP to the SW of the main larger feature - that's the spoiler for cold fans. The journey is fairly predictable from there with the Azores HP raising heights across Europe but I'm not seeing a hugely active mobile Atlantic at T+240.

Just to add 12Z Control ends with a strong anticyclone over Northern Poland and a push of frigid air into central Europe. The last vestige for cold fans would be the 00Z Parallel.

Conclusion - the switch to a milder more Atlantic-driven weather pattern looks inevitable from the end of this week but how long it lasts and what form it takes is far from resolved. Plenty of signals for heights to become more influential over Europe and the chances of some form of mid-latitude block look reasonable but whether that would be in a position or orientation to bring cold to the British Isles is doubtful at this time. I think we need to get the block in place first - what I'm not seeing is the zonal express of deep LP crossing west to east and in fact the Atlantic looks unseasonably quiet past mid month. It may well be we will have to just wait for the next amplification and while the NH profile isn't brilliant, I've seen a lot worse and all the models keep heights over the Pole. I'll leave those looking at other factors to judge the situation but while the overall picture doesn't look inspiring in the short to medium term it's not what we've seen in recent winters.

[booferking]

Ec started out well with that first low PV got a right hammering the 2nd low didn't play ball but time is on are side small changes to the tilt and positioning of that low and the outlook would look a lot different still positive going forward. 

Edited December 6, 2020 by booferking

[Alexis]

All I'm reading are people taking for gospel the forecast for our little area of the planet and ignoring the trends in the rest of the northern hemisphere. 

[feb1991blizzard]

Another big SSW signature CFS run.

[mulzy]

Outer reaches of the extended EPS - best of the winter season so far - high heights to the north and west as previously advertised; low heights to the south and finally low heights showing up over Russia.  Is this the start of a trend?

Edited December 6, 2020 by mulzy

[Scott Ingham]

11 minutes ago, Alexis said:

All I'm reading are people taking for gospel the forecast for our little area of the planet and ignoring the trends in the rest of the northern hemisphere. 

People are reading charts at face value. What is shown at 168 hours will not be what its like at 0 hours. Based on background signals, ensembles and clusters and known model bias how will that roll forward. That is forecasting from charts that far out. When I see people posting charts as gospel I just have to face plant my hand hahaha!!

[northwestsnow]

Less said about the EC mean the better this evening...

[Daniel*]

30 minutes ago, dragan said:

nothing positive at the moment for cold lol

You are a bit of a wind up merchant it seems...lol. Anyway in the here and now it is pretty cold and will remain chilly over the next 5 days, the ARPEGE model is forecasting barely above freezing highs in London tomorrow courtesy of lingering thick freezing fog. This would be the coldest London has been in daytime since March 2018, today quite a few places in East Anglia had an ice day or very close to one. Models are also showing few snow showers in the SE tomorrow evening from southern North Sea. Not an insignificant number have already seen falling snow from this diluted cold north and south, which was told to bring only cold rain. When we turn milder there is no suggestion the hemispheric picture is going to want to lock it in, there's a lot of good stuff to watch for coldies much more than usual in early December.

Edited December 6, 2020 by Daniel*

[Kirkcaldy Weather]

1 minute ago, northwestsnow said:

Less said about the EC mean the better this evening...

Looks pretty good to me mate  

Arctic high, split TPV and the big block out east 

[northwestsnow]

Just now, Kirkcaldy Weather said:

Looks pretty good to me mate  

Arctic high, split TPV and the big block out east 

Agreed, its the Atlantic sector that looks crap....

[booferking]

1 minute ago, Kirkcaldy Weather said:

Looks pretty good to me mate  

Arctic high, split TPV and the big block out east 

Arctic high coming to meet Russian high definitely very positive moving forward.

[MATTWOLVES 3]

52 minutes ago, Jason M said:

I personally don't see anything that points to deep cold in our part of the world and tbh have struggled to understand the high level of expectation over the last couple of weeks. That said, I completely respect that others are maybe seeing something I'm not. Interestingly, it seems that anyone who pays attention to GFS 'has no logic' or is a 'troll'. I would argue the opposite in that anyone who disregards any model completely is lacking in logic plus denigrating people with a different view is textbook trolling.  As Obi Wan Kenobi observed 'only a Sith deals in absolutes'. At the very least lets try to be respectful of differing views.

The reality is that GFS has a good level of support from its ensemble suite so it does need to be given some regard. I often disagree with IDO (especially around use of day 10 mean charts as they just tend to climatology IMHO), but on this occasion I find myself in broad agreement. As always, I want to be wrong but for me the prognosis is nothing very cold in the next 10 days (I'm tempted to say 14 days). Increasingly we are seeing more suggestions of heights to our south over Iberia as a response to the low sat in the Atlantic. Once that happens its pretty much game over for anything other than a transient PM airmass. From memory I think John Holmes came to a similar (albeit more informed) view yesterday from his charts.

Where do we go from here? The form horse would be SW / NW split, followed by UK / Euro high over Xmas period and our usual zonal new year. Just my opinion and probably wrong but hey ho.

Good level headed post Jason.. And we should most definitely respect other members posts and thoughts, even if they don't coincide with our own personal views! I for one have been guilty in the past of not liking other posters thoughts when they don't match my own. And that I regret, fortunately I know longer go down that path, and either keep out of the heated debates or give them credit for there opinions! There is certainly know point in accusing other members of trolling just because we do not like their analysis! 

Right then... Yesterday's EC long range anomalies... I covered them briefly after a quick glance... After a bigger inspection, they point to a rather cold December overall... For January they point to around avarage or a tad below values.. These are a ruff guideline for the month in the whole, we could still witness milder spells followed by colder ones through the month! February is again being showed as a warmer than average month and has been for some time! 

This is not the whole story as much of Central and Northern Europe is being highlighted as above normal too. Also worth noting is Central and Eastern areas of the USA are also being shown to be warmer than average... This is all along way off and shouldn't necessarily get you thinking the Winter is a write off!! But on balance the EC as been going with this theme since September... And it certainly can't be discarded! In this warming world we can never rule out numerous Winters going above avarage. But I remain some hope of at least a little Interest during the season, but I also wouldn't be overly surprised if this Winter failed to deliver also... But here's hoping I'm proven wrong.. 

Enjoy your evenings.... Its nearly Christmas ssssssss..

Edited December 6, 2020 by MATT☀️

[Scott Ingham]

36 minutes ago, dragan said:

from the perspective that the million pound computer models are not showing it lol, nor are the humans who get paid to translate the computers are not talking about cold either.

Im sure as you say a cold outbreak is possible, but then so is a mild outbreak.

By the way, i love cold and want to see it as much as any obsessed maniac on here, i’m not a ‘mildy’

Exeter talk about snow showers down to low levels at times in the East.... that wording is how they always start out before a snowy spell. They will say to high ground only if they don't 

[Allseasons-Si]

13 minutes ago, feb1991blizzard said:

Another big SSW signature CFS run.

You could of posted this to go with it Feb for Feb he! he!

 

[IDO]

42 minutes ago, bluearmy said:

The ecm op looks out of the spread n scandi by day 10 - that nearly always means it’s wrong. The ridge will not give way that quickly 

Isn't the Arctic high a driver of the circulation of the lower-heights on its perimeter, clockwise, east>west moving the chunk of the displaced tPV from Siberia in the direction of Scandi?

This surely will impact negatively on heights to our NE? The op does seem progressive compared to the means in that regard but it may simply be ahead of many ens? Saying that, a d10 ecm chart is really not what it should be these days.

[keithlucky]

51 minutes ago, Steve Murr said:

@IDO Please stop going on about poxy day 7 8 & day 9 GFS when its going to be wrong at day 5 & 6.

Or at least put some reality in your posts - The GFS looks nothing like the Euros at say 5 & 6 with a split low > that means when eventually it does come round theres only 1 model that was wrong in the short term > The GFS.

These are the forecast odds from me tonight.

GFS 5% with its bowling ball low at day 5 / 6 

The rest of the 95% split down the middle of probability will lead to a cold or mild solution depending on the angle of the jet & subsequent low at 144.

ICON > COLD > Negative tilted

ECM > MILD > Positive 

UKMO > somewhere in the middle.

The latest from met office they are uncertain what will happen Wednesday on will the warm move west to east across UK, or will the Russian HP move west deflecting the Warm front to the south of UK.Total confusion reigns.

[ICE COLD]

21 minutes ago, mulzy said:

Outer reaches of the extended EPS - best of the winter season so far - high heights to the north and west as previously advertised; low heights to the south and finally low heights showing up over Russia.  Is this the start of a trend?

I had just read the meto update and then you posted this and they are very similar. They mention the chance of very cold nights . Let’s hope the trend continues mulzy