Model Output Discussion - moving into Winter

[Rayth]

14 minutes ago, Dave Kightley said:

I would say we need the pattern further south on GFS .. to the point there really isn't a cold spell for south on that run as the battleground of SW and E is to far N.. to the point it could avoid give northern blocking a cold air mass.. such a lemon run for the south really

What I do find interesting is the appetite for blocking to keep reinvigorating in some form , so at least there’s a signal there, it’s been noted on here that the real fireworks ( if they are to happen) will take a few bites of the cherry before the pattern is set in 

Then we have the possibility of what catacol mentioned, a complete drop of the signal then grasped again, it’s all intriguing and way more interesting than a rampant PV

[That ECM]

It’s not winter wonderland but it will be very noticeable the difference.  

[Kentspur]

Well for me the GFS ensembles this morning are much better on this 0z suite than last nights 18z. It's clearer further north id suggest but even for my location in Kent there's a strong clustering of colder options present.

Even the likes of Nov-Dec 2010 had the odd blip along the road. 

Keep the faith 

[Mark Smithy]

6 hours ago, terrier said:

It’s not about been pushed back. Look at the trend. We are heading colder and the building blocks are there for something much more potent further down the line. We are in a much better position than we have been in recent years. Certainly beats mild westerly winds and Atlantic dross. The polar vortex at the moment is like boxer on the ropes. Just a case of the final knock out punch. 

It's perhaps worth noting though that the "this is better than previous years" is a line which gets repeated by cold lovers on every forum every single winter. I suspect this is more a case of us hoping it to be true rather than what the models are showing. There really isn't anything unusual or out of the ordinary so far this autumn (and it is still autumn). Yes there's a bit of blocking out in Siberia, which may or may not build into Scandinavia, but that's pretty normal.

Also, and I mean this politely not rudely so please don't take it that way, yes we are "heading colder". It's been a mild autumn and December is about to start, with it the winter season. So, yes, it's going to get a little colder as we come into the winter season.

Yesterday afternoon / evening saw a deluge in the west country with wild winds. Very much still an Atlantic onslaught. The 18z and then the 0z GFS suggest a flacid easterly which then gives way to something more like a southerly (again). It will cool down but perhaps the most notable feature of both runs is that the Atlantic onslaught might finally be abating. Although I do note that this has potential for considerable rain around the 5th/6th December.

A cooler, possibly cold, spell is still quite likely but no guarantee of much of an easterly. And it may pep up again on the GFS. UKMO 0z still thinks so. But generally it's best to take charts out past T168 with a big pinch of salt. Maybe that's why UKMO stop there. Sensible people.

[KTtom]

Synoptically, ECM the best of the usual bunch this morning. We do seem to be getting some sort of pattern being agreed on ar last....initial slack easterly finally  blocking off the Atlantic, pulse of heights to eastern Greenlant around day 6, low to the south west turning winds south of easterly. Temperatures nothing to write home about. Anything to raise an eyebrow still over 10 days away.

Excellent, well written and accurate post from Mark above.  

Ecm day 6:

[Dave Kightley]

ECM from 192 hours hmmm pass like GFS ... 

[SLEETY]

Ecm looked good until 168,then it wants it to warm up from the South,probably one of the warmest runs in the pack after 168 as it seems to be nearly every single time

Wrong anyway the way the block moves away then comes back in the last frame

[TSNWK]

Ecm is so close to being a good run.. up to 192.. then 216 and 240.. not sure.. and I'll say it... West based nao risk showing its hand.   Defo steps backward on narina since yesterday's 12z 

[Skullzrulerz]

7 hours ago, Met4Cast said:

Yikes.. 

Pretty sizeable shift in the ensembles there. The problem we've had for days now is still there, a complete lack of access to cold air despite the blocking. 

We must be the unluckiest country in Europe for getting any cold air here.

It's been a issue for the past few days that to simply put, anything noteworthy for cold... Isn't there in the short time or is beyond day 10/pushed back.

It's going to have to be a second yellow card for this "cold" spell.

 

 

 

[SLEETY]

GFS one of the warmest runs again in the critical part of the run for us and the near continent/Lots of colder options ,16c difference between the op and some of the others,useless

[mountsbaysnow]

I'm beginning to get that winter 21/22 feeling again 

[That ECM]

If people have the expectations of walking through 6 inches on powder in a weeks time then I guess I can understand disappointment.  Gfs is the only output that goes beyond T240 and it has been suggesting a blocked scenario. This is the T240 from ecm. Does this show a blocked scenario? Is this, on a broad scale, a good place to start the season?  
 

 

[tight isobar]

8 minutes ago, SLEETY said:

Ecm looked good until 168,then it wants it to warm up from the South,probably one of the warmest runs in the pack after 168 as it seems to be nearly every single time

Wrong anyway the way the block moves away then comes back in the last frame

168- pinned itself  on yesterday’s 12z as the slash point via the ops, The ens will reflect the non- need for panic on the 00z- And imo we’ll soon see cross model regeneration of wanted Synoptics. The ops doingwhat the ops WILL do b4 eventually getting into the mode. What a place to be in going into December....

[tight isobar]

8 hours ago, tight isobar said:

168 hrs- we can have a large degree of confidence of @ Dripping point!.. the lobes will fight it out yet it’s getting more assured that the north east takes the jugular!.. and thus the dripping starts ticking... and as momentum sits in sync... notability block formats start processing.... I think we - need to think of the cold getting to our shores a fair bit earlier.than present thinking-. and we’ll see this nxt 48 hrs as we gain!!!

Yesterday’s post for reference @168 - via the raws.. Chill out

2 minutes ago, Adam lufc said:

Led up the path again. 

Just knew the sensational charts last night would fail.

All those means and black hole anomolies are an utter joke! Waste of time.

Have a day off

Edited November 27, 2022 by tight isobar

[sheikhy]

Cmon guys rekax!!ukmo and gfs and ecm are darn good in the reliable no downgrades at all!!yes it goes tits up a bit after a bit but after looking at gfs ensembles the op once again is at the top end from day 7 or 8!!it keeps doing this!!infact the ensembles look better than the 18z ones!!

[mbrothers]

Just now, sheikhy said:

Cmon guys rekax!!ukmo and gfs and ecm are darn good in the reliable no downgrades at all!!yes it goes tits up a bit after a bit but after looking at gfs ensembles the op once again is at the top end from day 7 or 8!!it keeps doing this!!infact the ensembles look better than the 18z ones!!

Spot on and a million miles better than this time or in fact any time last winter

[Dave Kightley]

Hmm the trough firstly want going SE not NE why it brings slightly less cold air in from the South . To be fair and someone said about a NWly not showing on GFS this.morning does I think hmmm is the truth maybe the first lot collapse then a second is more successful.. in FI

Edited November 27, 2022 by Dave Kightley

[sheikhy]

3 minutes ago, mbrothers said:

Spot on and a million miles better than this time or in fact any time last winter

Mate after viewing the ecm and ukmo they look better than yesterdays 12zs!!the gfs op is very close to outlier territory!!we just need the op to finally go with one of the colder options and this place shall go mad on a different level lol!!

[jules216]

7 hours ago, Catacol said:

 

Jules would have us believe that this never happens anymore - and we know sub tropical high pressure is getting more and more stubborn as the years roll by - but the longer we keep the ridge to the north, and especially if it doesnt retrogress too far west, the more likely a Romanian positive anomaly will fade. This, of course, is all built on the foundation of GFS forecasting

Its not that I would make you believe its not happening anymore, but evidence is there around the start of December a possible cold spell has slipped away because that "Rimanian" high. Not to forget last week easterly where cold from Belarus took a "last minute" northward track flooding Poland and parts of Czechia with cold and snow but northerly track meant potential blocking got mixed out and high pressure there again to the rescue from south. Its just a begining and already 2 ocasions the potential slipped away,now we are looking at possibly something after 10.12. dont forget Tamaras words we wont be riding this Ninoesque AAM blocking forever. Also prospects of temporal -NAO(could turn out to be west based) and we are loosing Ural high and heat flux. Remember Christmas 2021 turned out to be west based -NAO then we lost Pressure on stratosphere. So there is a big risk of "fruitless Scural high retrogressing to west based -NAO and no more pulses of strat warming cemented by destructive interference of Nina when it matters most. Tíme will tell.

Edited November 27, 2022 by jules216

[Captain Shortwave]

The models aren’t far away from producing something of note for northern areas as cold air builds across Scandinavia and is driven towards the U.K. on that easterly wind.

 

The current Synoptics do suggest that the south could struggle to really see anything more than a couple of chilly days thanks to being under the cyclonic flow of that Iberian low. But at this point I would say that there is still a chance that the cold air to the north east might be upgraded and offer greater influence compared to the modelling at the moment.

Beyond this - Patience is required, the pattern is still blocked and could easily swing towards something more significant.

[sheikhy]

8 minutes ago, Captain Shortwave said:

The models aren’t far away from producing something of note for northern areas as cold air builds across Scandinavia and is driven towards the U.K. on that easterly wind.

 

The current Synoptics do suggest that the south could struggle to really see anything more than a couple of chilly days thanks to being under the cyclonic flow of that Iberian low. But at this point I would say that there is still a chance that the cold air to the north east might be upgraded and offer greater influence compared to the modelling at the moment.

Beyond this - Patience is required, the pattern is still blocked and could easily swing towards something more significant.

There was no cold air as such across the continent few days ago but all of a sudden as we gettin closer colder uppers seem to develop and upgrade!!

[IDO]

The macro pattern remains the same; a great 16-day mean on the GEFS:

 

...though the usual caveat as to how far south that will dive as it interacts with other variables.

London GEFS: Problems: 

 

The GEFS show good confidence up to D6 with a cooling down, SE'ly. But the trend, post then, is what others pointed out a few days ago, encroachment of milder uppers. The majority now with that warm up, though still some, including the control avoiding that scenario. By the end of today we should know the fate of D6-D12 viz a UK cold pool or not (also N to S variation).

The usual issues that crop up as we enter the reliable, the disruption from the Atlantic trough, the smaller features that act as spoilers, and the fact we are early in the season and no quick access to cold, unless we get the cards falling nicely into place. 

Edited November 27, 2022 by IDO

[Ali1977]

GEM, ECM and GEFS mean at day 10. Let’s not be downbeat, we’ve rarely been in this position early Dec. Let’s just get the continental feed in and see what happens. 

 

And I’ll add the JMA day 10 too

Edited November 27, 2022 by Ali1977

[seabreeze86]

There is that much blocking the models are going to struggle to nail down the correct outcome and will struggle for some time 

We are in the game for cold which is more than can be said in the vast majority of early Decembers. 
 

This will be a slow burner if it comes of we as always in the UK need a bit of luck .

Edited November 27, 2022 by seabreeze86

[Penrith Snow]

Any easterly was always going to be mediocre in the short term, no chart ever showed a wintry spell before the 7th December.

If we do get a proper cold spell it will be around mid December following the halting of the Atlantic and a lengthy spell of high pressure and slack cool easterly winds, both GFS and ECM have toyed with this idea and I think its still on the table.

Andy