Model Output Discussion - Winter arrives

[MATTWOLVES 3]

1 hour ago, SqueakheartLW said:

Here's one for Christmas from the GFS Extended run today

Also the 12z CFS run too

I know I don't rate the CFS very much but it has very much been calling this winter as mild and zonal more or less throughout December to February really right from around mid October on it's 9 monthly runs and with the way the AO and NAO look to be heading positive then rather annoyingly it would seem both the CFS and most of the seasonal models look to have called this winter correctly.

You occasionally get these sudden freaky cold runs on the CFS but in the last few weeks they have become so rare and all I see on most of them are reruns of December 2015.

I feel we missed our golden opportunity last winter to be fair with the patterns we had that didn't quite line up favourably and as we know in the UK if we miss any cold chances it can often be a long time before we get another one.

Cold snaps at best most likely and if we'll be lucky if we get anything more than a 2 day wonder at any stage

I hate to keep harping on about the same thing here,but how on earth can you say the seasonal models have called this correctly? You would need to be at least half way through the winter to make that kind of call!

And regarding CFS..its bit like going to costcutters for ya shopping,when we've got access to the Harrods of models out there!

In the short term...snow possible tonight,I'm not expecting a great deal though as milder air chases in behind it.

Perhaps a greater chance of something wintry over the weekend as temps begin to fall again...and perhaps more of a chance of suprise snowfall during Sunday night,and into Monday!.

Beyond that I just don't care.

As Danny Glover used to say in Lethal Weapon...im to old for this Sh@t

[Georgina]

On 02/12/2021 at 13:26, MATTWOLVES said:

I hate to keep harping on about the same thing here,but how on earth can you say the seasonal models have called this correctly? You would need to be at least half way through the winter to make that kind of call!

And regarding CFS..its bit like going to costcutters for ya shopping,when we've got access to the Harrods of models out there!

In the short term...snow possible tonight,I'm not expecting a great deal though as milder air chases in behind it.

Perhaps a greater chance of something wintry over the weekend as temps begin to fall again...and perhaps more of a chance of suprise snowfall during Sunday night,and into Monday!.

Beyond that I just don't care.

As Danny Glover used to say in Lethal Weapon...im to old for this Sh@t

This is why beginners like me get so confused by people calling off winter on the 2nd December ! And from my few years of following this thread the CFS isn’t the most reliable model , so when people put posts like this it’s really really confusing

[mountain shadow]

32 minutes ago, Battleground Snow said:

It's not really nonsense is it?

It's a statistically proven phenomenon that has direct evidence of affecting the UK's climate in winter.

Granted, it's not sole influence, and not at a very high amplitude, but it can't be discounted either.

 

What is the Madden-Julian Oscillation?

WWW.METOFFICE.GOV.UK

---

The Madden-Julian Oscillation is characterised by an eastward spread of large regions of enhanced and suppressed tropical rainfall, mainly observed over the Indian and Pacific...

 

I do apologise, my original post was very vague.

I am of course very aware of the MJO and its potential influence on our weather particularly when it is of a high amplitude in a favourable phase.

We are now entering a period where the tropospheric PV is starting to really strengthen and a large portion of the vortex looks like setting up shop in the NE Canada/W Greenland area of doom. The spread on the MJO into phase 7 is fairly large and the mean is not of much amplitude, I believe, to override the strengthening vortex.

It will certainly be interesting to see what amplitude the MJO does actually achieve in phase 7 in a couple of weeks and what influence it has on our weather, if any.

 

 

[blizzard81]

1 hour ago, Cold Winter Night said:

Yes, this is interesting.

It's visible in the clusters and regimes.

The 192h-240h clusters this morning have moved to a NAO+ dominated picture. The accompanying big jump away from cold stands out in the De Bilt 2m temperature plume.

That move at 192h is visible in the regime chart (that only goes as far as 192h) as well.

However, interestingly, the clusters in the extended are dominated by BLO+ (Scandi blocking) regimes.
A 31 member majority goes for BLO+ against 20 for a NAO+ regime.
So that Ural High moving West is a serious option in the extended period.

That there are only a few members showing real cold in the De Bilt plume has to to with the alignment of the block. If it's positioned too far South, we get Southerlies and Southeasterlies from Greece instead of Easterlies and Northeasterlies from Siberia.

Anyway, all this FI depends heavily on what is going to happen before 120h, so it's way too early to put confidence in any outcome.

Thanks for showing those clusters which add credence to the projected long term outlook. Of course this could change but there is much evidence overall certainly not to rule out a block close to our east or/and directly over the UK as we approach Christmas. 

[MATTWOLVES 3]

49 minutes ago, Georgina said:

This is why beginners like me get so confused by people calling off winter on the 2nd December ! And from my few years of following this thread the CFS isn’t the most reliable model , so when people put posts like this it’s really really confusing

Yeh I'm aware of this Georgina,it can be difficult at times to follow even when your quite knowledgeable! There will be many contrasting views on this Forum,and you will learn alot,but also very sensible to keep an open mind...and as you become better skilled in this art we call forecasting, you will be better prepared to make your own judgements!

But always remember one golden rule...background signals lead the models...whatever they are showing,the models will eventually cater into there forecasts of these downstream changes for instance. So MJO cycles are quite important regarding what cycle we are entering(the higher the better)...The strength of the Vortex and where its situated will also be a big player in how we pan out for this part of the world. Then you have all the big events across the tropics...standing waves etc...knock on affects from these can take quite a time to have implications on our atmospheric conditions.

So whatever is taking place right now may not be showing on the current model output...but could well be in a 2 or 3 weeks time. Never let sole Operational runs cloud your judgement,and take long range model forecasts with a large pinch of salt.... as there will always be a large degree of climatology normal bias factored in at such long lead times.

@blizzard81 great minds think alike..either that or we are posting from the same household mate

Edited December 2, 2021 by MATTWOLVES

[Battleground Snow]

3 minutes ago, mountain shadow said:

I do apologise, my original post was very vague.

I am of course very aware of the MJO and its potential influence on our weather particularly when it is of a high amplitude in a favourable phase.

We are now entering a period where the tropospheric PV is starting to really strengthen and a large portion of the vortex looks like setting up shop in the NE Canada/W Greenland area of doom. The spread on the MJO into phase 7 is fairly large and the mean is not of much amplitude, I believe, to override the strengthening vortex.

It will certainly be interesting to see what amplitude the MJO does actually achieve in phase 7 in a couple of weeks and what influence it has on our weather, if any.

 

 

I hear conflicting information on whether la Nina interferes with the convection associated with the MJO, I suppose the cooler waters of the pacific in theory  dull the thunderstorms (amplitude on the graph) once they reach that region, but as most of the cooler water is in the far Eastern Pacific, maybe convective activity won't reduce until the thunderstoms cross most of the pacific. If they get stuck in the middle of the Pacific that may be ideal

If anyone else has any knowledge on this, it would be good to try further my understanding.

[blizzard81]

27 minutes ago, Georgina said:

This is why beginners like me get so confused by people calling off winter on the 2nd December ! And from my few years of following this thread the CFS isn’t the most reliable model , so when people put posts like this it’s really really confusing

I suppose the secret is not to be totally swayed by others poster's opinions whichever way they might lean. As you gain more knowledge of the models you will be able to rely on your own judgements more as opposed to relying on others . 

[blizzard81]

3 minutes ago, MATTWOLVES said:

Yeh I'm aware of this Georgina,it can be difficult at times to follow even when your quite knowledgeable! There will be many contrasting views on this Forum,and you will learn alot,but also very sensible to keep an open mind...and as you become better skilled in this art we call forecasting, you will be better prepared to make your own judgements!

But always remember one golden rule...background signals lead the models...whatever they are showing,the models will eventually cater into there forecasts of these downstream changes for instance. So MJO cycles are quite important regarding what cycle we are entering(the higher the better)...The strength of the Vortex and where its situated will also be a big player in how we pan out for this part of the world. Then you have all the big events across the tropics...standing waves etc...knock on affects from these can take quite a time to have implications on our atmospheric conditions.

So whatever is taking place right now may not be showing on the current model output...but could well be in a 2 or 3 weeks time. Never let sole Operational runs cloud your judgement,and take long range model forecasts with a large pinch of salt.... as there will always be a large degree of climatology normal bias factored in at such long lead times.

That is spooky lol  

[damianslaw]

Reliable timeframe fairly short at present, 96 hrs I say. The models thereafter show a deepening low pressure spinning in fron the west. It's depth and position will be unknown until short timescales.. already we are seeing the models show a slightly less deep feature and it tracking a little further to the south. UKMO has it filling quickly over the UK, likewise ECM - this all indicates to me the block to the east isn't going anywhere fast.. whilst it may well retreat further east for a bit, it won't be eroded. I can see an easy path to a blocked outlook from mid Dec onwards with perhaps a bit of a SW flow in the interim but the Atlantic will hit the buffers... heights building through UK and merging with heights to the NE. Many longer term forecasts are suggesting it. The theme of 2021 could well continue short bursts of the Atlantic interspersed by lengthier blocked patterns.

[syed2878]

3 hours ago, LetItSnow! said:

12 days away... that's all I will say

  12 days it may be how other models are fairly good at picking up those patterns and most of the time they do verify let’s hope this time is different

[Cloud 10]

Certainly one to watch in the 5 to 6 day timeframe,with nearly all models spinning up a deep low in the Atlantic,the ECM looks a bit extreme with its almost 150mph gusts though.

 

The LP does weaken a bit the closer it gets to the UK,but still makes for rather uncomfortable viewing.

 

[Kasim Awan]

Very good. Cold wedge driving southeast. Plenty of potential.

[Mike Poole]

5 minutes ago, Kasim Awan said:

Very good. Cold wedge driving southeast. Plenty of potential.

Yes, the doesn’t blow up anywhere near as much on the ICON 12z.  Still some way to go if it is to take a sufficiently southerly track.

[topo]

Dear God,

Please make ICON 12z come true. 120mm of snow on the coast for the next 6 days. Please.

Thank you.

[Duane S.]

1 hour ago, Georgina said:

This is why beginners like me get so confused by people calling off winter on the 2nd December ! And from my few years of following this thread the CFS isn’t the most reliable model , so when people put posts like this it’s really really confusing

It’s quite simple. Just ignore any comments that write off winter on what is only the 2nd day of winter .

They hold no weight whatsoever. Even moreso in respect to the start of this particular winter I say… 

[blizzard81]

The brutal cold is going to be on the Siberian side as opposed to the Canadian side. We just need the mothership high over Siberia to advect it westwards. If only it was that simple . 

Edited December 2, 2021 by blizzard81

[Frosty.]

22 minutes ago, topo said:

Dear God,

Please make ICON 12z come true. 120mm of snow on the coast for the next 6 days. Please.

Thank you.

I just dropped in to see what condition my condition was in.. ..anyway, the icon doesn’t look so iconic too me! …peace.. out..we’re not in Norway..and we’re certainly not in Kansas anymore… , !..  

Edited December 2, 2021 by jon snow

[blizzard81]

1 hour ago, MATTWOLVES said:

Yeh I'm aware of this Georgina,it can be difficult at times to follow even when your quite knowledgeable! There will be many contrasting views on this Forum,and you will learn alot,but also very sensible to keep an open mind...and as you become better skilled in this art we call forecasting, you will be better prepared to make your own judgements!

But always remember one golden rule...background signals lead the models...whatever they are showing,the models will eventually cater into there forecasts of these downstream changes for instance. So MJO cycles are quite important regarding what cycle we are entering(the higher the better)...The strength of the Vortex and where its situated will also be a big player in how we pan out for this part of the world. Then you have all the big events across the tropics...standing waves etc...knock on affects from these can take quite a time to have implications on our atmospheric conditions.

So whatever is taking place right now may not be showing on the current model output...but could well be in a 2 or 3 weeks time. Never let sole Operational runs cloud your judgement,and take long range model forecasts with a large pinch of salt.... as there will always be a large degree of climatology normal bias factored in at such long lead times.

@blizzard81 great minds think alike..either that or we are posting from the same household mate

I thought I could hear somebody in my loft

[MATTWOLVES 3]

32 minutes ago, blizzard81 said:

The brutal cold is going to be on the Siberian side as opposed to the Canadian side. We just need the mothership high over Siberia to advect it westwards. If only it was that simple . 

What ya thinking mate...the flow looks North of West come the end of the run..with a segment of vortex dropping further into the North Atlantic...surely would still be pretty cold air,even taking into account some moderation.. Do I detect the pattern trying to push Heights further out of the urals quadrant! I wouldn't say this is a bad run...but the uncertainty still looks key! And it's better to see more of the vortex dislodged further away from home. Plus we still have low Heights around S Europe 

Judging by the Exeter thinking...perhaps more of these fronts diving SE...the risk of rain turning to snow at times and with it Frost and ice over the next couple of weeks...I think we are back in the game...a few days back it looked mainly mild and uninspiring tbh.

Edited December 2, 2021 by MATTWOLVES

[Catacol]

7 hours ago, jules216 said:

How uncanny, pattern shaping Up now in Europe is almost exactly as it was last december yet everywhere else it looks the opopsite, this anomaly is also very close to the pattern at the begining of June 2021 which preceeded the warmest June/July period in some regions like mine. There we go.

 

Looks extremely good if stratospheric disruption is your thing. Same with your previous post. Having just had the 3rd warmest autumn on record, and looking the impacts of CC straight in the eye over the last 20 years, vortex disruption is the path to winter. I nearly wrote "only path" - that would be overstating it a bit because as we just saw with storm Arwen tropospheric patterns can still bring moments of wintry extreme and that storm a month later would have been very good indeed, but these are outlier events now. 1 year in 5 we can hope for a SSW with beneficial impacts that will run roughshod over any CC bias. I still see the setup this year as being conducive to an SSW and the arrival of the Ural High now, looking like a sustained feature, is great news. Ongoing Alaskan cold via a trough is the perfect partner. Watch and wait....and see if we can shatter the vortex and watch the cold run amok!

[That ECM]

T120 Ireland take cover. And then it pretty much stalls. T144.

Edited December 2, 2021 by That ECM

[tight isobar]

How good is ya model memory??! I said  and it’s happening, ultra lobes in near timeframe (now) going on separate journeys. Mother lobe dropping- father lobe gaining A’s parameters are felt, tropospheric vibrations.. without other layer ramifications. We could end up with an almighty limpit lobe at the usual sector but with a Siberian breaking feed.. and with block format holding the usual chuck westerly regime!!!.. then its spill down to us @mid latts.. I said bizarre many times @this winter .. and it’s shaping up!!

[fromey]

3 minutes ago, That ECM said:

T120 Ireland take cover.

Is that a central pressure of 951MB!! In another part of the world that’s a hurricane! 5 days out!! Surely we are not taking this seriously  

[That ECM]

On 02/12/2021 at 16:03, fromey said:

Is that a central pressure of 951MB!! In another part of the world that’s a hurricane! 5 days out!! Surely we are not taking this seriously  

If two models are showing this then it needs watching.  955 on gfs. At t120. Jeez trying to post on phone is hard with my eyes. thanks @fromey

 

 

Edited December 2, 2021 by That ECM

[blizzard81]

15 minutes ago, MATTWOLVES said:

What ya thinking mate...the flow looks North of West come the end of the run..with a segment of vortex dropping further into the North Atlantic...surely would still be pretty cold air,even taking into account some moderation.. Do I detect the pattern trying to push Heights further out of the urals quadrant! I wouldn't say this is a bad run...but the uncertainty still looks key! And it's better to see more of the vortex dislodged further away from home. Plus we still have low Heights around S Europe 

Judging by the Exeter thinking...perhaps more of these fronts diving SE...the risk of rain turning to snow at times and with it Frost and ice over the next couple of weeks...I think we are back in the game...a few days back it looked mainly mild and uninspiring tbh.

Yeah matey. Looking west/north west but I was musing about further down the line. There shouldn't be any shortage of cold uppers if we can tap into something of a more easterly persuasion