Model Output Discussion - Spring Has Sprung

[northwestsnow]

45 minutes ago, bluearmy said:

At least everyone’s catching up with their sleep!

more of the same on the nwp 

seems a v slow road to the removal of euro heights and the movement of the rump of the upstream vortex across to the Asian side (if that does actually happen) 

00z runs are an utter car crash.

 

Got to hope things change,soon..

Edited January 23 by northwestsnow

[TillyS]

8 hours ago, Met4Cast said:

This must be the most boring the outlook has looked all winter, at least we had something to talk about with the storms etc during the first half & indeed this week. 

Going forward though? Nothing but “bleughh” across all modelling & ensemble suites. Perhaps we’ll get a bit of amplification at some point in February but I can’t see it at the moment. 

I think the kind of euro high that’s showing up across various model runs at the moment i.e. stuck over northern France / Benelux / north Germany is the worst of all possible outcomes for UK winter cold. It leaves us in a predominantly south-west mild, moist, feed but as you say without any of the drama of storms or even northerlies. It’s the lack of northerly blocking and a resurgent jet pummelling across the north of the high and into Scandinavia that’s going to be especially disappointing for some. This sort of thing:

 

These outputs are eating up prime winter time.

[winterof79]

Shannon has entered the room

[northwestsnow]

Just now, winterof79 said:

Shannon has entered the room

That's good.

We need EC ens to show similar now ...

 

[IDO]

The GEFS is showing zonal to D16. Mean at D8-16:

As expected, the N/S divide for the worst of it.

The members look like there is uncertainty beyond D10, but that is untrue. Just as we move into FI, the timing of each zonal interlude varies, and the sine waves cancel each other out, hence the 850s in FI at 0.

With the TPV running the show due to the lack of any force, we are relying on removing the tPV from the Euro/N American side of the NH, and the mean Siberian block continues to thwart that. D16 GEFS mean:

These types of charts are winter killers for the UK.

[joggs]

Not looking good across most runs for a coldie.

Seasonal's could be a big bust for Feb.

Not that I'm saying winter is over.

Edited January 23 by joggs

[LetItSnow!]

30 minutes ago, northwestsnow said:

00z runs are an utter car crash.

Another garbage winter passing us by, I can write this script - +NAO Fab and then raging -NAO in March and April.

Concerning build of heights so strongly so early in the season. An early start to summer for our folks to the south of us. Hopefully not another summer from hell setting up across Europe. If there’s any consolation at least winter may still be alive and well for our Scandinavian friends. They’ve been very lucky to miss the mild muck that’s plagued us most the time. 

Edited January 23 by LetItSnow!

[AO-]

26 minutes ago, LetItSnow! said:

Concerning build of heights so strongly so early in the season. An early start to summer for our folks to the south of us. Hopefully not another summer from hell setting up across Europe. If there’s any consolation at least winter may still be alive and well for our Scandinavian friends. They’ve been very lucky to miss the mild muck that’s plagued us most the time. 

Good Morning,

Exactly my concern. This setup is the worst possible for people in Spain. On the other hand, this wasn't very different last year but then May came around. Winter or high pressure for us often means rain or unsettled conditions for them. To give an impression of the EC this morning:

 

again dryer than before, but cold members are hard to find. Nevertheless could the day 10 chart of EC be the beginning of something later on. I do not have time to go through the different members to discover the synoptics at the end of the coldest members, but I'm curious what they come up with. If the EC46 is correct we may see some high pressure over the Atlantic. 

 

Edited January 23 by AO-

[Mike Poole]

ECM clusters, nothing of interest from a coldie perspective until T240, so here’s T264+:

Signs on both clusters 2 and 3 of an Altantic ridge, and the removal of Euro heights, still not really sure this is gaining traction, seems more prevalent this morning than last night though.  Cluster 1 remains flat.  

[nick sussex]

It’s like Groundhog Day .

The same old zonal pattern with strong Iberian high repeated ad nauseam.

The GEFS show a few better solutions post day ten .

The ECM op does finally split up the PV day ten but still leaves a lobe over Greenland .

The wait continues ......

[Singularity]

Some here seem to view a strong Iberian high as a driver of weather patterns - but this is not so, it’s a response to drivers. In this case the forcing leads to attempts to establish a high over N Europe which are countered by the AO being too positive (likely related to the unusual stratospheric events - who’d have rationally bet on that one?), meaning that in a sense, amplification becomes trapped over S Europe.

Due to the MJO & AAM setup, further attempts to shift the high N are likely in the coming weeks (which can happen abruptly even with a strong Euro high). Signs are the first of those in 6 days time will likely fall short & boost the high over C/S Europe instead. Then, however, we are seeing the models tend to raise polar heights as we head into Feb. That improves the chances of the next attempt being successful, regardless of how current modelling paints the picture (they’re not actually that reliable for week 2+, it’s just easier to predict +NAO because it happens way more often than -NAO in N Atlantic climatology).

Emphasis on chance here. As Tamara has said many times over the years, there’s no magic bullet for HLB patterns. As I’ve said before, the most likely outcome isn’t always what happens. With this in mind I’ve found forecast model watching a lot less stressful.

Edited January 23 by Singularity

[Penrith Snow]

I a  not sure Singularity is correct about the Iberien High being a response not a cause, its chicken and egg.

Check out a 100 years of historical data pre 1988 and you won't find such a massive and persistent Iberain/Mediterranean High as we see modelled now, it just didn't happen and of course the current persistant Bartlett is only the latest in a long line since the 1999's.

IMO, the Iberian High dominance is due to the expansion of the sub tropical Hadley Cell in response to a warming world, the expanse forces the Jet Stream north preventing the PV leaving its natural home ie Greenland, it happens occasionally of course like last week but any change is pushing againt the new normal and is quickly crushed.

This I feel is the over riding factor and overwhelmes other natural signals that might encourage Northern Blocking, hence the late January early February forecast debacle.

Watch the MJO if you like but it will make little difference 

Andy

[Dennis]

BOMM MJO ---febr has some in mind  (MJO event forseen)

[sebastiaan1973]

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/mjoupdate.pdf

So the MJO enters phase 6 strongly, long term is uncertain. According to EC46 it is improving. 

Edited January 23 by sebastiaan1973

[ANYWEATHER]

10 minutes ago, Penrith Snow said:

I a  not sure Singularity is correct about the Iberien High being a response not a cause, its chicken and egg.

Check out a 100 years of historical data pre 1988 and you won't find such a massive and persistent Iberain/Mediterranean High as we see modelled now, it just didn't happen and of course the current persistant Bartlett is only the latest in a long line since the 1999's.

IMO, the Iberian High dominance is due to the expansion of the sub tropical Hadley Cell in response to a warming world, the expanse forces the Jet Stream north preventing the PV leaving its natural home ie Greenland, it happens occasionally of course like last week but any change is pushing againt the new normal and is quickly crushed.

This I feel is the over riding factor and overwhelmes other natural signals that might encourage Northern Blocking, hence the late January early February forecast debacle.

Watch the MJO if you like but it will make little difference 

Andy

Yes it's modelled now but how reliable are the models? Anyway ,a drying out trend partly due to to Iberian high after today ,which I can say is a positive trend especially for southern uk ,we don't want anymore rain for at least a month! Even at day ten the unreliable timeframe it shows high pressure into the south of the uk, and even the wacky unreliable timeframe from gfs at T+384 hrs it shows a similar pattern. Probably fairly correct at day ten ,given the synoptics,  perhaps we will have to wait to mid-February before we see a dramatic pattern change......

[Duane S.]

11 minutes ago, Dennis said:

BOMM MJO ---febr has some in mind  (MJO event forseen)

It will change of course but thats incredible how the mean, over 6 days, steadfastly refuses to enter phase 8 !
 

Amplified P7 should (eventually) at least help our cause P6 at this stage of winter in this ENSO state is more of a wild card I’d say?

[sebastiaan1973]

26 minutes ago, Penrith Snow said:

I a  not sure Singularity is correct about the Iberien High being a response not a cause, its chicken and egg.

Check out a 100 years of historical data pre 1988 and you won't find such a massive and persistent Iberain/Mediterranean High as we see modelled now, it just didn't happen and of course the current persistant Bartlett is only the latest in a long line since the 1999's.

IMO, the Iberian High dominance is due to the expansion of the sub tropical Hadley Cell in response to a warming world, the expanse forces the Jet Stream north preventing the PV leaving its natural home ie Greenland, it happens occasionally of course like last week but any change is pushing againt the new normal and is quickly crushed.

This I feel is the over riding factor and overwhelmes other natural signals that might encourage Northern Blocking, hence the late January early February forecast debacle.

Watch the MJO if you like but it will make little difference 

Andy

Science seems to back your thoughts. 

he Azores High is a persistent atmospheric high-pressure ridge over the North Atlantic surrounded by anticyclonic winds that steer rain-bearing weather systems and modulate the oceanic moisture transport to Europe. The areal extent of the Azores High thereby affects precipitation across western Europe, especially during winter. Here we use observations and ensemble climate model simulations to show that winters with an extremely large Azores High are significantly more common in the industrial era (since ce 1850) than in pre-industrial times, resulting in anomalously dry conditions across the western Mediterranean, including the Iberian Peninsula. Simulations of the past millennium indicate that the industrial-era expansion of the Azores High is unprecedented throughout the past millennium (since ce 850), consistent with precipitation proxy evidence from Portugal. Azores High expansion emerges after ce 1850 and strengthens into the twentieth century, consistent with anthropogenically driven warming. https://www.nature.com/articles/s41561-022-00971-w

 

5 minutes ago, Duane S. said:

It will change of course but thats incredible how the mean, over 6 days, steadfastly refuses to enter phase 8 !
 

Amplified P7 should (eventually) at least help our cause P6 at this stage of winter in this ENSO state is more of a wild card I’d say?

I guess we all remember BOM in december  

[Eagle Eye]

35 minutes ago, Penrith Snow said:

I a  not sure Singularity is correct about the Iberien High being a response not a cause, its chicken and egg.

Check out a 100 years of historical data pre 1988 and you won't find such a massive and persistent Iberain/Mediterranean High as we see modelled now, it just didn't happen and of course the current persistant Bartlett is only the latest in a long line since the 1999's.

IMO, the Iberian High dominance is due to the expansion of the sub tropical Hadley Cell in response to a warming world, the expanse forces the Jet Stream north preventing the PV leaving its natural home ie Greenland, it happens occasionally of course like last week but any change is pushing againt the new normal and is quickly crushed.

This I feel is the over riding factor and overwhelmes other natural signals that might encourage Northern Blocking, hence the late January early February forecast debacle.

Watch the MJO if you like but it will make little difference 

Andy

Its both a driver and a response but larger changes in the overall setup in AAM and MJO would change it more than it would affect them. Therefore the second rise in AAM or still a small chance this rising AAM is important. Yes because of the horizontal temperature gradient it can drive zonal mean zonal wind fairly continentally but the EAMT is more of a driver of the Asian pattern than the Iberian high, as in my mind it's a sudden and strong event. Almost akin to a major warming being stronger than an initial westerly zonal wind. Once the support for an Iberian high is lost it won't be able to sustain itself. Hence, if there is a complete flip in the zonal extension over the north Atlantic (the north Atlantic Jet, maybe the NAJ) , then the Iberian high doesn't magically stay. The hard thing is getting that, almost needs to happen in this situation with a disconnected jet phasing between the NPJ and the NAJ and therefore the support for a poleward propagating Rossby wave over north America transferring eastward is likely. This AAM rise may semi-support that but the CAD over eastern USA that's possible may be overriden by the extended jet despite the equatorward NPJ movement. However, to say Winters over because of the Iberian high when there's that second potential AAM rise, isnt necessarily wrong but it's not really right either. Depends on how the MJO and AAM both go beyond the current rise which is mostly not poleward propagating. 

Yes climate change expansion of the Azores high has made it harder but it's by no means impossible to get rid of it, we do, however, need a stronger zonal mean zonal wind change than we did in years past. Cold spells still happen, they haven't disappeared, it's just harder to get and sustain them.

Edited January 23 by Eagle Eye

[Stravaiger]

28 minutes ago, Penrith Snow said:

I a  not sure Singularity is correct about the Iberien High being a response not a cause, its chicken and egg.

Check out a 100 years of historical data pre 1988 and you won't find such a massive and persistent Iberain/Mediterranean High as we see modelled now, it just didn't happen and of course the current persistant Bartlett is only the latest in a long line since the 1999's.

IMO, the Iberian High dominance is due to the expansion of the sub tropical Hadley Cell in response to a warming world, the expanse forces the Jet Stream north preventing the PV leaving its natural home ie Greenland, it happens occasionally of course like last week but any change is pushing againt the new normal and is quickly crushed.

This I feel is the over riding factor and overwhelmes other natural signals that might encourage Northern Blocking, hence the late January early February forecast debacle.

Watch the MJO if you like but it will make little difference 

Andy

This - 100%. So often climate change isn't looked at as a driver but it has fundamentally changed the game. Expansion of the Hadley cell, GHG and CFC-induced stratospheric cooling leading, etc., all of these factors are uniting to increase the likelihood of strong, coherent PVs and a northward push of the sub-tropical high into Southern Europe during winter.

Of course there will be times when other drivers can override these factors and we get pressure in Europe to fall - we've seen it a few times since November - but the winter season is fundamentally changed by the increased likelihood of long periods where really high heights to our south effectively block any cool or cold air from covering the British Isles.

The way I think about it is that we're playing the same game but the cards in the deck are different now, with many more leading to anomalously mild conditions. We'll still occasionally get to play great hands but the odds of them appearing have lengthened considerably.

[Gowon]

Don't worry folks - the KMA's got this:

[Don]

22 minutes ago, Duane S. said:

It will change of course but thats incredible how the mean, over 6 days, steadfastly refuses to enter phase 8 !
 

Amplified P7 should (eventually) at least help our cause P6 at this stage of winter in this ENSO state is more of a wild card I’d say?

But the other day, wasn't the mean refusing to enter phase 7 and instead going into COD?

9 minutes ago, Gowon said:

Don't worry folks - the KMA's got this:

Heights to the south again.....

[TEITS]

46 minutes ago, Penrith Snow said:

I a  not sure Singularity is correct about the Iberien High being a response not a cause, its chicken and egg.

Check out a 100 years of historical data pre 1988 and you won't find such a massive and persistent Iberain/Mediterranean High as we see modelled now, it just didn't happen and of course the current persistant Bartlett is only the latest in a long line since the 1999's.

IMO, the Iberian High dominance is due to the expansion of the sub tropical Hadley Cell in response to a warming world, the expanse forces the Jet Stream north preventing the PV leaving its natural home ie Greenland, it happens occasionally of course like last week but any change is pushing againt the new normal and is quickly crushed.

This I feel is the over riding factor and overwhelmes other natural signals that might encourage Northern Blocking, hence the late January early February forecast debacle.

Watch the MJO if you like but it will make little difference 

Andy

Very good post and very difficult to argue against.

Only positive is the models will get better because they cannot get any worse from a coldies perspective.

[Derecho]

53 minutes ago, Dennis said:

BOMM MJO ---febr has some in mind  (MJO event forseen)

We all know how the BOM MJO phase 7 prediction turned out in December.

I hope we do get into phase 7 but it looks very uncertain to me going by the other models. Phase 6 in January is followed by very mild weather and in February it is cyclonic. We could get stuck in phase 6 for quite a while.

EC does get there on it's ens mean but If we are to get out of this rut, the increasingly slow progression towards a phase 7 means I'm not hopeful of much interesting until the second week of Feb (around the 10th).

By that point we have to start relying on increasingly impressive synoptics to get a good cold spell. If we can't get that I'd prefer a Feb 1998 type of month.

Feb 2018 did show we can get something potent but time is starting to work against us now.

Sorry but my glass is half empty today.

I also do believe the Iberian high is becoming more prominent due to climate change. Problem with that is if we get lower heights over the Azores (which is more common in El Nino late winters), this can actually make things even milder if the Iberian high doesn't subside we end up with a deep fetch SW'ly. Feb 1998 again being a prime example.

Not suggesting it will go that way at this early stage but the GFS is very stubborn with the Euro heights. EC also very poor at day 10.

[Gowon]

22 minutes ago, Don said:

But the other day, wasn't the mean refusing to enter phase 7 and instead going into COD?

Heights to the south again.....

The heights over greenland are nicer.

[Penrith Snow]

45 minutes ago, TEITS said:

Very good post and very difficult to argue against.

Only positive is the models will get better because they cannot get any worse from a coldies perspective.

Indeed, just been checking historical charts since 2000 and while persistent Bartletts are frequent (as we all know)  the size and extent of the current Iberian/Mediterranean High is off the scale.

This is why I have now lost faith in using teleconnections as a forecasting tool, two weeks ago every signal pointed to HLB in late January resulting in great EC 4 weekers and an usually positive MetO MRF, it appears they all couldn't have been more wrong.

And before anyone says I am only looking at UK centred micro developments I am not, the whole NH profile is the exact opposite of those the teleconnections had indicated.

In science when you run an experiment and the outcome isn't what you expected you go back to the drawing board not run it again and again hoping for a different result.

Andy