Model Output Discussion - Into Winter

[swfc]

11 minutes ago, northwestsnow said:

There is still way to much Shannon entropy over Xmas but this morning I can't help but feel it's slipping away now.

Like you I'm more concerned about the longer term now.

I do hope something hasn't gone wrong with the background drivers ,surely the wintry potential suggested late Dec early Jsn wasn't predicated on the MJO ...

Did shannon ever work behind bar in travelers arms Sheffield Relax folks its only 18th December

Edited December 17, 2023 by swfc

[NewEra21]

You just know at some point to really put the nail in the coffin, the US will eventually see the cold return and lock us into more wind and rain as the jet fires up.

This month has been a huge opportunity to hit something in terms of cold, and we still can’t get things to fall for us. Let’s hope something happens come the new year, and we’re not still saying the same come February yet again!

Edited December 17, 2023 by NewEra21

[That ECM]

17 minutes ago, TSNWK said:

This is what makes it all the more frustrating…vortex has not set up shop in Greenland at all thus far.. and we still can’t catch a break…

My point is that there will be more opportunities. wow there’s some proper doom in here this morning.  

Edited December 17, 2023 by That ECM

[northwestsnow]

1 minute ago, That ECM said:

My point is that there will be more opportunities. wow there’s some proper doom in here this morning.  

There will be more opportunities for sure.

I think the mood is despondent because a lot of the older members have seen ,time and time again over the years, a tonne of potential but very sparce picking when it comes to results on the ground for us.

We do have NINO / eQBO and the destructive IOD is in decline so I agree with you that we will see further opportunities..

[Kasim Awan]

This Winter does have features of classic mild El Nino winters. Warm September, November cold spell with a rapid strengthening of the zonal flow and development of the Azores high into December.

Rather than to the extent of 2015 and 2019 there is a slight tripole and blocking signal therefore the magnitude of mild will probably be shy of winter 2015/2019, with slight tendency towards 2014/15 and 2018/19. Logically a halfway house which would mean CETs in winter months between 5 and 6C, with any proper cold limited to Scotland, and snow chances still fairly widely due to scope for brief cold zonal interludes one of which we may see around Christmas and around the new year.

Edited December 17, 2023 by Kasim Awan

[KTtom]

Its the constant modelling of the Euro high after Christmas which is turning into a bit of a worry... It may be 10 days or so away but its a constant theme of the latest gfs runs and now ECM is in range of that time period.  

[northwestsnow]

4 minutes ago, KTtom said:

Its the constant modelling of the Euro high after Christmas which is turning into a bit of a worry... It may be 10 days or so away but its a constant theme of the latest gfs runs and now ECM is in range of that time period.  

Precisely why I'm despondent. 

As soon as we see a signal for Euro warmth highs they seem to gather momentum,yet when we see charts full of potential at say the day 10 range,they nearly always get watered down to nothing.

 

 

Edited December 17, 2023 by northwestsnow

[Derecho]

On 04/12/2023 at 14:17, Derecho said:

You think the MJO will go into phase 8 as soon as the 12th? I think it'll take a bit longer then that, more like the 16th or 17th.

The phase 3 we are currently in isn't particularly strong. I don't think it's as simple as the MJO being the sole reason for our cold spell falling apart. Weather forecasting would be a lot easier if it was.

Had a Scandi high built and the Atlantic not fired up, this weeks synoptics would have been a lot different. Any transient building of high pressure to our south could have easily ridged towards Scandi.

A problem I have with ' the MJO will go into phase 7 then 8' is that it is far too confident in the assumption that it will happen. Just look at the scatter on the latest EC, there doesn't have a huge amount of confidence. It could still end up in the COD.

Further still, even if it does end up in phase 7, the December composites for an El Nino phase aren't brilliant.

Phase 8 and 1 are better of course but that's a long way off, if it ever happens at all. A phase 1 doesn't even have the strongest temperature signal here.

More composites can be viewed here:
 

MJO.html

WWW.AMERICANWX.COM

 

Whereas the MJO didn't fall for us here, it wouldn't have mattered if things had alligned better further east. The MJO is one of a miriad of factors that influences global atmospheric circulation patterns, as is an SSW. However with so much uncertainty it can be as I say akin to chasing unicorns. Last year there was a constant anticipation of big impacts from an SSW but all it lead to was a cold day in early March in what was otherwise a mild and very wet month.

Another problem with SSWs is that they more often occur later in winter. The last one I can remember that favoured us earlier on was the SSW event of January 2013. Indeed it can even work against us if the vortex doesn't split or does so unfavourably. Whilst NW Canada got temps 15C below normal in February 2019 the UK was basking in its first 20C of that month.

I'll only get genuinely interested when some exciting output appears within T240. The GFS is better after this point but it's a long time away. 

Teleconnections are fascinating but often lead to being chased up the garden path. 

 

Sadly this post has aged all to well. When high pressure gets the chance to build over Iberia it is becoming extremely difficult to shift. That innocuous rise in pressure on the first Saturday of the month has really hit us hard.

From there it has set the wheels in motion for a much more typical El Nino December. The EC is pretty confident the MJO will remain in the COD, though phase 1 is possible later.

So the BOM forecast for earlier in the month was truly woeful.

Just look at the spread of above average temperatures as we go into the Christmas period.

So even that intense cold air over Russia has been swept away with ease. I'm convinced some of the 2009-2013 blocking may have been caused by ocean circulation because the dominance of high pressure over Spain since then is something to behold. On rare occasions it can be overwhelmed but the expansion of the Hadley cell due to climate change is hurting us.

Hopefully another factor can fall in our favour but maybe netweather should fund a cloud seeding initiative over Spain to save our winters. I'm hoping the second half of the winter falls into more typical El Nino behaviour. Without the first week this December would have been very mild indeed.

Edited December 17, 2023 by Derecho

[Guest]

 Bugger! - heralds the inevitable arrival of Mother in law!

You can't help thinking  if us coldies collectively fell into one giant barrel full of t*ts we'd all come up sucking our thumbs!

[TillyS]

5 minutes ago, KTtom said:

Its the constant modelling of the Euro high after Christmas which is turning into a bit of a worry... It may be 10 days or so away but its a constant theme of the latest gfs runs and now ECM is in range of that time period.  

Absolutely right.

The persistence of this high is the most notable feature of model outputs recently.

I think if this were a Scandinavia High, or a mid-Atlantic High, or a Greenland High it would be the talk of the town. This kind of high can be very persistent and there’s no easy route to UK cold with it stuck there.

[Kasim Awan]

4 minutes ago, TillyS said:

Absolutely right.

The persistence of this high is the most notable feature of model outputs recently.

I think if this were a Scandinavia High, or a mid-Atlantic High, or a Greenland High it would be the talk of the town. This kind of high can be very persistent and there’s no easy route to UK cold with it stuck there.

I said before I believe we are seeing signs of a very persistent Bartlett forming. It's moving around yes but no high pressure is static all highs do this.

Edited December 17, 2023 by Kasim Awan

[SollyOlly]

49 minutes ago, bluearmy said:

The ens haven’t really promised anything notable whereas the ops have 

it was the ens that showed the Atlantic heights pushing back across to our south whilst the ops were often looking for something way deeper on the trough 

It’s a squib …….

Damp squid for Xmas dinner...nicely cooked, one hopes. 

Edited December 17, 2023 by SollyOlly

[TillyS]

2 minutes ago, Kasim Awan said:

I said before I believe we are seeing signs of a very persistent Bartlett form. It's moving around yes but no high pressure is static all highs do this.

Yes and Paul B******* (almost a swear word on here!) said he once counted 8 anticyclones one after another in a single winter that were collectively eponymous. They move around a bit as you say but the blasted thing keeps re-appearing.

Still early days and it may all change but after a very promising start to December it’s an incredible turnaround. We’ve lost all of the cold pooling and northern blocking is currently absent. 

Someone mentioned climate drivers, which is a different topic but relates to the model outputs. How often in recent years have we seen all this model promise get destroyed by warming?

 

[Jason M]

6 minutes ago, Kasim Awan said:

I said before I believe we are seeing signs of a very persistent Bartlett forming. It's moving around yes but no high pressure is static all highs do this.

When Bartlett comes for Christmas he generally doesn't leave until well into the new year. Its amazing how in recent years we are always in exactly the same position running into the holiday period.

[Kasim Awan]

8 minutes ago, TillyS said:

Yes and Paul B******* (almost a swear word on here!) said he once counted 8 anticyclones one after another in a single winter that were collectively eponymous. They move around a bit as you say but the blasted thing keeps re-appearing.

Still early days and it may all change but after a very promising start to December it’s an incredible turnaround. We’ve lost all of the cold pooling and northern blocking is currently absent. 

Someone mentioned climate drivers, which is a different topic but relates to the model outputs. How often in recent years have we seen all this model promise get destroyed by warming?

 

Often happens in El Nino years, warm September was a giveaway aswell. EQBO + El Nino combination works in our favour a little though.

Edited December 17, 2023 by Kasim Awan

[northwestsnow]

12 minutes ago, TillyS said:

Yes and Paul B******* (almost a swear word on here!) said he once counted 8 anticyclones one after another in a single winter that were collectively eponymous. They move around a bit as you say but the blasted thing keeps re-appearing.

Still early days and it may all change but after a very promising start to December it’s an incredible turnaround. We’ve lost all of the cold pooling and northern blocking is currently absent. 

Someone mentioned climate drivers, which is a different topic but relates to the model outputs. How often in recent years have we seen all this model promise get destroyed by warming?

 

Spot on.

It feels like the wheels are falling off at a rate of knots.

We are relying on the more positive background drivers but if anything NWP is hurtling towards a Euro warmth high  +AO/NAO..

Edited December 17, 2023 by northwestsnow

[That ECM]

4 minutes ago, TillyS said:

Someone mentioned climate drivers, which is a different topic but relates to the model outputs. How often in recent years have we seen all this model promise get destroyed by warming?

Model promise has gone previously on numerous occasions. People can attribute it to whatever they like. Imo the computer models, much improved as they’re, still struggle to predict past T240 for sure. 
 

I’ve seen most out put for the last 18 years or so, was various names on here before but forgot passwords etc so just set up as new as it was easier for me, trust me I’ve seen many a potential cold period go “wrong”. 
 

 

[Bricriu]

26 minutes ago, northwestsnow said:

Precisely why I'm despondent. 

As soon as we see a signal for Euro warmth highs they seem to gather momentum,yet when we see charts full of potential at say the day 10 range,they nearly always get watered down to nothing.

 

 

Is a Euro high plaguing our winter what  the glosea seasonal progged for the winter months ?

Edited December 17, 2023 by Bricriu

[northwestsnow]

Just now, Bricriu said:

Is Euro high plaguing our winter what  the glosea seasonal progged for the winter months ?

Glosea has flipped to +NAO /AO for January I believe.

[BartyHater]

Forget Where’s Wally, the question is where’s winter?

According to GFS Christmas Day looks set to have an absence of cold across 80%+ of the inhabited Northern Hemisphere, with even huge swathes of central Russia seeing temps well above average. 
Eastern Russia and N China buck the overall mild picture, but even there temps looks pretty close to average, so it’s not just the UK that seems to have lost almost complete contact of winter this December.

[Kasim Awan]

Just now, Bricriu said:

Is Euro high plaguing our winter what  the glosea seasonal progged for the winter months ?

Not really a question it is more of a hard fact when you look at the amomaly maps.

[near northampton]

9 minutes ago, TillyS said:

Yes and Paul B******* (almost a swear word on here!) said he once counted 8 anticyclones one after another in a single winter that were collectively eponymous. They move around a bit as you say but the blasted thing keeps re-appearing.

Still early days and it may all change but after a very promising start to December it’s an incredible turnaround. We’ve lost all of the cold pooling and northern blocking is currently absent. 

Someone mentioned climate drivers, which is a different topic but relates to the model outputs. How often in recent years have we seen all this model promise get destroyed by warming?

 

Indeed, and before the the euro high was established, Spain broke its all time December high on the 12th December with 29.9c in Malaga. Much is talked about scandi cold pooling earlier in the December, no one it appears was looking the other way. Month after month of record high breaking temperatures across Europe. Of course that in itself is not a driver of our weather now?

[Bricriu]

Just now, northwestsnow said:

Glosea has flipped to +NAO /AO for January I believe.

A disaster. It really feels like we could be here in mid January still looking for signs of a colder weather in the extended. I really hope met4forecast is incorrect about us having to wait till the next mjo cycle in February for cold . He has gone quiet since his last post.

[Derecho]

6 minutes ago, Kasim Awan said:

Often happens in El Nino years, warm September was a giveaway aswell. 

A warm September doesn't equate to a mild winter, there is no physical mechanism linking the two.

[TEITS]

1 hour ago, northwestsnow said:

Looks like the operationals are leading the way.

I had been banking on the ens/eps but it doesn't look like thats going to pay dividends.

Back to feeing utterly deflated there is nothing worse ,for me anyway,than wind and rain over Xmas and that looks clear favourite this morning..

Moving forward I do hope some of these positive background signals come to the fore ,soon.

You are indeed correct. As is often the case the operationals always prove more reliable than ensembles at short range. For example the 0Z GFS OP was much warmer than the GEFS mean on the 27th Dec and yet the 06Z GFS is the same. When this happens and is supported by the GEFS control run then the GEFS mean slowly increases towards the operationals in future runs.

As for positive background signals. Funny how during the past 10 years despite all these different positive signals we always end up with the same winter weather pattern i.e SW,lys with pressure relatively high to the S of the UK with very little signs of any blocking at N,ly lattitudes.

Maybe these teleconnection signals may of proved correct and gave the UK the promised winter wonderland many years ago. However are these positive signals being overridden due to changes in the global weather patterns due to a warming climate. If so then at the moment nobody fully understands how climate change will affect our weather patterns. You cannot make a successful prediction if you do not understand the cause.