Model Output Discussion - Christmas week and beyond

[bluearmy]

36 minutes ago, CreweCold said:

Yes it can...we've seen it in the past. It can happen very very quickly once the strat and trop couple, for example.

bloody annoying that we can’t see the ecm cross section any longer …

the gfs runs are still showing that increase in zonal flow making it down towards  1000hpa but it does then start to bounce back upwards 

And the extended clusters aren’t without amplification….

[Rain All Night]

13 minutes ago, goosey007 said:

Jan 1984?

Just looked this up - wow, that is a brutal angle of attack.

https://www.meteociel.fr/modeles/archives/archives.php?day=8&month=1&hour=0&year=1984&map=2&region=nh&mode=2&type=era

[danm]

6 minutes ago, CreweCold said:

We have to take into account that the past few weeks have seen a lot of cold air sat around our shores and also flooding into the N Atlantic. Any PM flow is likely to be less moderated than usual now.

Possibly, but by their very nature, cold zonality set ups tend to be transient and are often marginal for those areas that do see snow. High ground is the exception obviously. I’m guessing the Scottish highlands get most of their snow from polar maritime sourced airmasses.

Edited December 19, 2022 by danm

[goosey007]

2 minutes ago, RainAllNight said:

Just looked this up - wow, that is a brutal angle of attack.

https://www.meteociel.fr/modeles/archives/archives.php?day=8&month=1&hour=0&year=1984&map=2&region=nh&mode=2&type=era

Delivered big snow in south wales and many other areas that’s why i know that particular month year ….

[Eagle Eye]

Just a short post for now:

Alright so, I've noted an Atmospheric River a lot today but what can it's effects be. Let's have a look at a fairly major one in California last year:

Ours won't nearly be as strong as that but if we can get the cold strong enough for around Christmas time and the back edge of the AR can time itself with that we could find somewhere with a near Christmas (or maybe on Christmas) decent snowfall. Our AR hasn't gotten that much vertically integrated water transporting with it but that doesn't mean it can't bring a fair amount of precipitation with it and the back edge of these AR's tend to be colder so if we can time it will we may potentially see a lot of snowfall somewhere but surely nowhere near as much as the one last December. So, I'll keep monitoring the AR and you can monitor how the cold moves .

Edited December 19, 2022 by Eagle Eye

[Rain All Night]

1 minute ago, Eagle Eye said:

So, I'll keep monitoring the AR and you can monitor how the cold moves .

Deal!

[blizzard81]

Ecm ops not consistent over the last couple of days so this sows doubt in my mind about it's validity right now. Here's an example. 

[Cold Winter Night]

I'm actually surprised to see that EC46 keeps the heights to our North alive deep into January.

Week 2

Week 3

Week 4

Week 5

Week 6 (!!!)

Edited December 19, 2022 by Cold Winter Night

[chicken soup]

1 hour ago, tight isobar said:

 states the notion.. separation of the lows is now pinpoint for advancement!.. getting “binocular sync “- dictates the forward of rolling the Iberian orange arm to pastry.. and the commence of heights allowance into the mid latitudes b4 we could become struggling with Jetstream placement! Anyway whichever way your bid ya head- we are slowly getting jigsaw management!! .. but .. we need to look for the pieces in the kitchen draw... and put them together... !!! 

love your posts...though God help.anyone new who comes across one.

[ICE COLD]

2 minutes ago, Cold Winter Night said:

I'm actually surprised to see that EC46 keeps the heights to our North alive deep into January.

Week 2

Week 3

Week 4

Week 5

Week 6 (!!!)

Well at least the blocking signal is still there . Weeks 5 and  6 is nuts

[mulzy]

3 minutes ago, Cold Winter Night said:

I'm actually surprised to see that EC46 keeps the heights to our North alive deep into January.

Week 2

Week 3

Week 4

Week 5

 

Week 5 is good.  The countdown is on!

[LRD]

Good news - EC46 shows possible scandi high anomalies

Bad news - in the 2nd half of January so unlikely to verify

Jan 23rd - 30th

Strong old signal at that range! But it's screaming cold and snow and a classic

Next week could still go either way with strong anomalies to the west and NW but also to our SE. I'm guessing the SE heights will win because a high anomaly there - when pressure is usually relatively high (compared to Greenland) - must be pretty powerful

[Bricriu]

7 minutes ago, Cold Winter Night said:

I'm actually surprised to see that EC46 keeps the heights to our North alive deep into January.

Week 2

Week 3

Week 4

Week 5

 

Yes, its hard to reconcile that with the Trop and strat Vortex connecting. If i may ask a question,  are we seeing such eye candy output on the GFS because of what it thinks will happen with the MJO. Is it overreacting to that signal hence heights rising to Greenland? I am not a praying man, but if the the GFS turns out to be correct , i will get down on my knees and worship it. Seriously though if it has got this wrong it's going to get some flak from everyone.

Edited December 19, 2022 by Bricriu

[Rain All Night]

5 minutes ago, chicken soup said:

love your posts...though God help.anyone new who comes across one.

It took me a few weeks to learn how to read them, but it was worth it!

[blizzard81]

4 minutes ago, Cold Winter Night said:

I'm actually surprised to see that EC46 keeps the heights to our North alive deep into January.

Week 2

Week 3

Week 4

Week 5

Week 6 (!!!)

Could this mean ecm is spotting a SSW? I wonder. Interesting that the met are also seeing greater chances than usual of cold episodes deep into January. 

[Stravaiger]

Well what a spell of model watching this has been...I don't about you guys but when the stakes are this high and the uncertainty is this great, I find the model watching very compelling. There are still massive differences between the Big 3's 12Z runs regarding the shape, structure and centre of the lows around the UK at T+72, weirdly agreement is almost better at T+96, but even then notable discrepancies persist.

The point is we still don't know how things are going to pan out later on this week and, I'm afraid, trying to pin one's hat on anything at the moment, whether that's ensemble trends or operational run's consistency, is likely to give an unjustified sense of confidence, esp. for the period after Christmas.

The good news is that cold weather still very much has a seat at the table. At least in the North. The bad news is that things are far from nailed on. You know the drill...more runs needed and let's pray for the result us coldies deserve.

[Cold Winter Night]

Another view of EC46.

NAO+ in January? EC46 not really interested.

Stunning update in my opinion, I did not see this coming.
Let it be right just this once...

[ICE COLD]

@Cold Winter Night have you got the zonal wind speed graph please ? Cheers 

[blizzard81]

1 minute ago, Stravaiger said:

Well what a spell of model watching this has been...I don't about you guys but when the stakes are this high and the uncertainty is this great, I find the model watching very compelling. There are still massive differences between the Big 3's 12Z runs regarding the shape, structure and centre of the lows around the UK at T+72, weirdly agreement is almost better at T+96, but even then notable discrepancies persist.

The point is we still don't know how things are going to pan out later on this week and, I'm afraid, trying to pin one's hat on anything at the moment, whether that's ensemble trends or operational run's consistency, is likely to give an unjustified sense of confidence, esp. for the period after Christmas.

The good news is that cold weather still very much has a seat at the table. At least in the North. The bad news is that things are far from nailed on. You know the drill...more runs needed and let's pray for the result us coldies deserve.

Very true - big differences between models in just a few days. Big uncertainty. 

[Cold Winter Night]

2 minutes ago, ICE COLD said:

@Cold Winter Night have you got the zonal wind speed graph please ? Cheers 

ECMWF | Charts

CHARTS.ECMWF.INT

 

[LRD]

Another representation of week 6 on EC46

 

[bluearmy]

1 minute ago, Cold Winter Night said:

ECMWF | Charts

CHARTS.ECMWF.INT

 

The zonal wind forecast very much in line with last Thursday.  A return to average after a strong week or so. No ssw in sight but no sustained roaring vortex either. 

[Cold Winter Night]

9 minutes ago, Bricriu said:

Yes, its hard to reconcile that with the Trop and strat Vortex connecting. If i may ask a question,  are we seeing such eye candy output on the GFS because of what it thinks will happen with the MJO. Is it overreacting to that signal hence heights rising to Greenland? I am not a praying man, but if the the GFS turns out to be correct , i will get down on my knees and worship it. Seriously though if it has got this wrong it's going to get some flak from everyone.

I don't know what is behind the GFS amplification signal, but the EC46 regime chart actually shows more support for Scandi heights than for Greenland Blocks or Atlantic ridges.

Edited December 19, 2022 by Cold Winter Night
typo

[blizzard81]

Control looks cold on ecm 

[bluearmy]

1 minute ago, LRD said:

Another representation of week 6 on EC46

 

The thing about week 6 is that the ec46 rarely churns out a week six chart very far away from climatology. 

Just now, blizzard81 said:

Control looks cold on ecm 

Mid lat sceuro high