Model Output Discussion - Into Winter

[swfc]

3 minutes ago, northwestsnow said:

Agreed.

But in the context of a flat EC it's not a trend we'd want to see ...

Indeed. If you also look to the far nne the arctic high and residual heights are not evident on the gfs 6z

Edited December 9, 2023 by swfc

[northwestsnow]

The changes earlier in the run have big knock on effects

0z

6z below

[nick sussex]

The GFS 06 hrs still displaces the Azores high but it’s a weaker effort with the wrong orientation and associated Scandi trough set up .

The later output is wildly different over the NH . You can always rely on the GFS to throw up all manner of solutions in FI with 4 runs a day ,

 

[That ECM]

I think many would take this at T0 and see where it went from there. 

[Nick2373]

     

I'll just leave this here. 

[northwestsnow]

8 minutes ago, Nick2373 said:

     

I'll just leave this here. 

Nice..

But it's 00z of course

[CoventryWeather]

Think people need to remember not to take every single OP run literally - there are going to be changes in the long term. Generally though, the GFS is consistently pointing towards an amplified pattern in the Atlantic - likely to be amplified further as it counts down due to models struggling with the MJO. Yes, people are worried about the flatter ECM solution, but the KMA (the Korean model) shows this too albeit still ends up a similar solution to the GFS. 

It will most likely end up with a ridge to the west, perhaps Greenland if the MJO is sufficient enough to provide enough energy up there, but how we get there (ie are we under a milder SWerly for a while) is still uncertain within the ensemble suites. 

Personally, I don't see why anyone's worrying, everything is going to plan like the professionals are saying ATM. 

Have a good weekend!

Edited December 9, 2023 by CoventryWeather

[jmp223]

One thing I noticed In the run up to our recent cold spell, the 06z always seemed to throw out stinkers of charts, which then be modified (positively for coldies) in the 12z.  It seems to be doing it again!

[NewEra21]

The overall pattern is still very much the same, that’s all that matters.

There’s obviously going to be slight differences run to run, and those slight differences make a huge difference to the UK.

But in the grand scheme of things, everything is going in the right direction. Whether we hit the jackpot or miss out, who knows. But this far out the pattern is all that matters.

[That ECM]

A step back or forward. I would suggest forward.

Edited December 9, 2023 by That ECM

[MJB]

3 hours ago, blizzard81 said:

I've never bought into this end of Dec cold spell. I'm just not feeling it. I actually hate seeing that arctic high these days - it never does us any favours. 

That's quite a bizarre comment, we aren't even 8 1/2 days  into the month and you are writing a cold spell at the end of the month, I understand if you are talking at 168 but end of the month. ? 

It seems if ECM isn't showing it, it ain't happening ?

Edited December 9, 2023 by MJB

[MJB]

1 hour ago, northwestsnow said:

I'm afraid 6z and 0z are chalk n cheese

Hmmmmm NWS, that isn't strictly true, both show HP to the West of the UK, so a similarity is there, just a difference in orientation..........surely. And at that range, it's not worth looking at the tiniest detail , the fact that we have a HP near us gives a chance of retrogression down the line.

[BartyHater]

1 hour ago, Battleground Snow said:

Not sure what your expecting before the 22nd?

We are looking for the high to be drawn up around this date to the north west from the next wave break

How amplified the mjo gets will probably dictate how far north the high gets and how long it sustains.

Not sure what your expecting before the 22nd?
 

Something that gives me hope that things will improve for cold after the 22nd…. I don’t see it, if you do then great, but the 06 has turned out a run that I was pretty much expecting to see based on my previous post.

Even at this stage I’d suggest a cold Christmas such as the one we were looking at just 48hrs ago, i.e under a flow from between N and E is no better than a 10/1 shot….whereas something similar synoptically to the 06GFS at 384hrs already looks more like evens.

My main fear is now the Xmas high slips even farther south and brings us back into the mild, wet SW’erlys, which really would be a massive kick in the proverbials considering the expected overall hemispheric pattern….but I certainly wouldn’t rule it out.

Edited December 9, 2023 by BartyHater

[Spikey M]

A gentle reminder that today is day 9 of Winter. Any alarm bells should be having snooze hit for atleast 2 months.

[bluearmy]

The gefs 06z hangs back a high anomoly from the Atlantic around T300 in line with the general direction of travel at this timescale. it’s a struggle to get the drop in euro heights backed far enough west in the 12/14 day period 

atm, the momentum is definitely with a mlb across the U.K. extended from the Atlantic high approaching Xmas weekend 

beginning to see a definitive trend to the Siberian ridge and western American ridging loosely meeting across the polar field - potentially assisted by the Arctic high which usually defaults to exiting the Arctic by one of these routes. That aligns the NH profile in its traditional west - east profile and makes it tougher for the Atlantic ridge to gain the traction we want to see. The 06z gefs certinainly a poor suite for Greenland heights post T300 with the Canadian vortex extending well across that region.  
 

to illustrate my point comparing yesterdays 06z with todays for Xmas eve 

    

Edited December 9, 2023 by bluearmy

[AO-]

God Afrernoon all,

 

Since I am new here, I would like to introduce myself and my weather interests. 

 

My name is Anco and I have been reading along with this forum for quite some time. I live in the Netherlands, Friesland to be exact, and for us it is as big an ordeal to get winter as here with you in the UK. The Atlantic is quite a spoiler wrt winter weather. As many of you I am a "coldie" and would like to see a winter like the ones in '63  or '79 (even more so) if possible of course due to AGW. 

 

Now to the present. I have some observations which I would like to share.  There is a lot of talk about teleconnections and wether they are picked up by the models it not and to what extent. But looking strictly at the model output, the anticyclone over the US might be one of the problems. We miss the pump near the eastcost of the US to elevate the high over the UK towards Greenland. This might be a welcome feature around the 17th when MJO phase 7 comes at stake. At that point we have seen in several outputs that the troposphere might be susceptible to a rise in geopotential over the North. I am not sure why so little members show this in the ENS. (Anyone with an explanation?) Maybe we first have to leave past 5 of the MJO before the models pick it up? At this moment I don't see the phase 7 reflected in the output. I would like anyone with some knowledge to reflect on that. 

[LRD]

Christmas is still up for grabs (I reckon it'll get colder but not spectacularly so) but it's grimly fascinating to see how warm we could get next week. Very unseasonal.

[LRD]

5 minutes ago, AO- said:

God Afrernoon all,

 

Since I am new here, I would like to introduce myself and my weather interests. 

 

My name is Anco and I have been reading along with this forum for quite some time. I live in the Netherlands, Friesland to be exact, and for us it is as big an ordeal to get winter as here with you in the UK. The Atlantic is quite a spoiler wrt winter weather. As many of you I am a "coldie" and would like to see a winter like the ones in '63  or '79 (even more so) if possible of course due to AGW. 

 

Now to the present. I have some observations which I would like to share.  There is a lot of talk about teleconnections and wether they are picked up by the models it not and to what extent. But looking strictly at the model output, the anticyclone over the US might be one of the problems. We miss the pump near the eastcost of the US to elevate the high over the UK towards Greenland. This might be a welcome feature around the 17th when MJO phase 7 comes at stake. At that point we have seen in several outputs that the troposphere might be susceptible to a rise in geopotential over the North. I am not sure why so little members show this in the ENS. (Anyone with an explanation?) Maybe we first have to leave past 5 of the MJO before the models pick it up? At this moment I don't see the phase 7 reflected in the output. I would like anyone with some knowledge to reflect on that. 

Welcome. Good first question to which I can not answer! Someone on here probably can though

[BartyHater]

14 minutes ago, bluearmy said:

The gefs 06z hangs back a high anomoly from the Atlantic around T300 in line with the general direction of travel at this timescale. it’s a struggle to get the drop in euro heights backed far enough west in the 12/14 day period 

atm, the momentum is definitely with a mlb across the U.K. extended from the Atlantic high approaching Xmas weekend 

beginning to see a definitive trend to the Siberian ridge and western American ridging loosely meeting across the polar field - potentially assisted by the Arctic high which usually defaults to exiting the Arctic by one of these routes. That aligns the NH profile in its traditional west - east profile and makes it tougher for the Atlantic ridge to gain the traction we want to see. The 06z gefs certinainly a poor suite for Greenland heights post T300 with the Canadian vortex extending well across that region.  
 

to illustrate my point comparing yesterdays 06z with todays for Xmas eve 

    

Good post…hopefully it’ll bring a dose of reality to the forum, because in reality the drift towards MLB pre and now hopefully over Xmas (we really don’t want the mild/wet rubbish back), has been signalled for at least 24hrs.

[LRD]

 No convincing signs of deep cold for Xmas from the GFS ensembles

The ECM clusters started to look really shaky from yesterday and things haven't improved (for cold that is)

[Jason M]

9 minutes ago, LRD said:

 No convincing signs of deep cold for Xmas from the GFS ensembles

The ECM clusters started to look really shaky from yesterday and things haven't improved (for cold that is)

We could see a short lived PM or even arctic outbreak, but its a longshot. Its one of those set ups that will tease in FI but not amount to much. We have been in far worse positions to be honest though.

 

[johncam]

3 hours ago, bluearmy said:

Because it’s a very useful tool when used without the usual drama that accompanies the op runs. especially for week 3 and 4. it’s been fairly consistent for the past two weeks ref late dec and Jan. we can review this in a months time. 

Is there any stats how how the EC46 performs. As all I remember is posters saying it got it wrong again .

[CameronWS]

Why so many negative when the MJO signal isn’t even being factored in yet to the models? Surely when that becomes apparent the blocking showing up is likely to increase.

[johncam]

1 hour ago, MJB said:

That's quite a bizarre comment, we aren't even 8 1/2 days  into the month and you are writing a cold spell at the end of the month, I understand if you are talking at 168 but end of the month. ? 

It seems if ECM isn't showing it, it ain't happening ?

It does have the best stats but this far out they will all be wrong when we get to day 0

[Bricriu]

20 minutes ago, CameronWS said:

Why so many negative when the MJO signal isn’t even being factored in yet to the models? Surely when that becomes apparent the blocking showing up is likely to increase.

I just wonder  do the UKMO factor it into their forecasts? Could it be the other models don't see it being amplified  enough to lead to a HLB. We have to hope it is as you say, and the ensembles will soon start showing support for a block that leads to cold  weather. 

Edited December 9, 2023 by Bricriu