Model output discussion - January cold spell ending, what next?

[Vikos]

Less people know that GFS after (imho) 240 has less data input in it's calculation and accuarcy drops dramaticly. So it often goes to return for "normal patterns", which for our region is west (at it's best) Hard to explain...

[Paul]

Errm, I think if it's ok to post up a viewpoint and a cherry picked chart or two that show colder solutions, those who do similar but with a milder looking chart, perhaps to do nothing more than highlight that the colder outcome isn't 'nailed on' or whatever else, then they deserve to be able to do that without getting brickbats from a select few. 

So, those getting all antsy and defensive just because someone dares not to go nuts over the cold potential right now, please stop. 

[Battleground Snow]

Control and mean at 228

I echo @snowking comments. With frequent warmings which should hold a negative AO for weeks  and squeeze the cold into the mid lats like a baloon We will have ample opportunities to strike it lucky over the rest of winter.

[Frostbite1980]

 In my eyes the general trend is looking good at present, there is plenty of scope for Atlantic ridging coupled with further warnings up above. At this juncture all we can look at is trends and IMO it is 60/40 cold and hopefully the ECM can build on that.....let's not run before we can walk whether you are a cold or warm lover!

Edited January 9, 2021 by Paul

[Methuselah]

3 minutes ago, Vikos said:

Less people know that GFS after (imho) 240 has less data input in it's calculation and accuarcy drops dramaticly. So it often goes to return for "normal patterns", which for our region is west (at it's best) Hard to explain...

But I've always believed that models run according to their initial data-input... How can that disappear after 240 hours?

[pureasthedriven]

17 minutes ago, That ECM said:

Yes gfs and tongue in cheek. I’ll worry if it gets to T72

72 minutes. 

[Paul]

2 minutes ago, General Cluster said:

But I've always believed that models run according to their initial data-input... How can that disappear after 240 hours?

Yep, it doesn't. The resolution does drop from 0.5 degrees to 1 degree after 192 hours though. 

[Vikos]

Just now, General Cluster said:

But I've always believed that models run according to their initial data-input... How can that disappear after 240 hours?

I am not sure, I can be something different. I read about it some time (years) ago. Can also be the density of data after that timemark. But I know that there is something after +240h in the GFS modelling. I will search for it and PN you

[winterof79]

The GEFS 240 mean remains steady and looks loaded.

A warm up of sorts seems to be being watered down

Edited January 9, 2021 by winterof79

[SteveB]

24 minutes ago, snowking said:

Yeah if anyone is looking for the exact synoptic pattern 10 days out you’re going to be disappointed.

Keep on following the overall longwave themes:

Heights rising to our NW

Asian vortex segment retrogressing into Scandinavia (and beyond....)

Big artic high (which is always poorly modelled beyond a few days)

Continued warming episodes in the stratosphere

 

For as long as the models continue to show these themes, we should all be happy. That’s as much as we can ask for right now.

And maybe a nationwide snow event....

[CSC]

Hello all, evening! 
it’s my opinion that the GFS has now developed some kind of ‘westerly bias.’ It seems confused with the possibility of extreme cold coming in from the east. I am sure in the coming days, this will correct, but it’s still wrong even 6 hours our. 
 

for example tonight it predicts as cold as -1 here in Brighton for midnight. It’s already -1 at 5pm and will probably go as low as -3 or -4. 
 

Exciting times ahead. Take any models with a punch of salt right now. Extreme cold may still happen next week.

[Ice Day]

I think the Control gets the award tonight for the best run so far!  228, 252 and 276

  

Absolutely stunning

 

[BLAST FROM THE PAST]

20 minutes ago, General Cluster said:

I'm not, for one minute, suggesting that SE France will enjoy 15C Uppers, in January... But, what intrigues me, is that there must be sufficient data for a state-of-the-art NWP to suggest that it might... Hey, ho, model-watching at its best?

    

And what are they say 8 days earlier Pete? Wild swings of the jetstream and extremes make it all possible.

 

BFTP

[Mike Poole]

12 minutes ago, Paul said:

Yep, it doesn't. The resolution does drop from 0.5 degrees to 1 degree after 192 hours though. 

I understood that the FV3 GFS retained the higher resolution throughout the run to T384.

[Notty]

GFS doesn't have a scooby what is going to happen after 12th:

 

Edited January 9, 2021 by Notty

[Jason H]

Those ensembles are all over the shop. All options are on the table. Pick a long range forecast out of that

[winterof79]

 PV Under pressure again

[TSNWK]

3 minutes ago, Notty said:

GFS doesn't have a scooby what is going to happen after 12th:

 

That's a shame seeing the op as a clear outliner.  Was expecting more support..

[Jason M]

2 minutes ago, Ice Day said:

I think the Control gets the award tonight for the best run so far!  228, 252 and 276

  

Absolutely stunning

 

Trouble is that they flatter to deceive. The temperature profile that sits behind them is more reminiscent of what we have just had. If I was any good at posting images I'd post each chart with the 850 profile alongside to illustrate as for lurkers it would really help to explain. Looking through the GEFS tonight there are still a few genuinely cold charts but they are mostly out beyond 10 days and there is nothing convincing. These northerlies always look dramatic on the 500 charts but the reality rarely matches! Get a proper easterly and its a different ball game, but I'm not seeing much evidence of that at present.

For me, we are not in a 'bad' place but equally if a big deep freeze is coming its not really showing its hand yet. The danger is that we look at everything through the lens of a background SSW and don't see what is in front of us. Based on tonight's output (not withstanding the usual ECM day 10 northerly later) I'd imagine Sidney would be happily munching through his winter stores right now but perhaps just holding a little in reserve in case of a sneaky beast turning up 

[Cheshire Freeze]

2 minutes ago, TSNWK said:

That's a shame seeing the op as a clear outliner.  Was expecting more support..

IMO the GEFS will not 'see' the pattern better than the op...and what have we had so far? 3/4 ops showing N Atlantic blocking by D10? The ensembles will not model the strat as accurately as the op...

Anyone expecting ensemble help at the moment is living in cuckoo land

Edited January 9, 2021 by CreweCold

[CSC]

1 minute ago, TSNWK said:

That's a shame seeing the op as a clear outliner.  Was expecting more support..

Don’t worry. I’m pretty sure all of GFS is wrong and it will get a lot colder than it’s currently showing 

[Chesil View]

We are at the 9th January. Anyone trying to put detail on something that might be happening around the 20th whether that be snowfall detail or a west or east based nao, is deluded, Whether you are an avid cold and snow fan ( like me) or one of the usual  misanthropes who don't believe any cold synoptic unless there's five feet drifts in their garden.

We all need to take Snowking's advice and just follow the patterns which at the moment look promising.

Nothing even semi reliable for the 20th onwards will appear until the the 15th so let's just enjoy the run in to what MIGHT be an jnteresting period of winter weather from a coldies point of view.

[Premiere Neige]

57 minutes ago, Johnp said:

I'm not sharing the excitement with others - what am I missing?

I'm looking for a long lasting cold spell, but GFS seems keen on a good northerly followed by a west based -ve NAO then Atlantic domination. 

Atlantic domination? Have I missed something? Like the Atlantic being all fired up? Last time I checked it was pretty much dead. The models are erring more towards a cold solution over the past few days...

[I remember Atlantic 252]

36 minutes ago, General Cluster said:

I'm not, for one minute, suggesting that SE France will enjoy 15C Uppers, in January... But, what intrigues me, is that there must be sufficient data for a state-of-the-art NWP to suggest that it might... Hey, ho, model-watching at its best?

    

Come on Ed, absolute ridiculous FI, GFS 12Z is decent, keeps hopes alive of northerly/cold around 18th, even that's too far in FI

[Scott Ingham]

4 hours ago, Tim Bland said:

GEM (CMC) is also outperforming both GFS GFSp and UKMO! It still doesn’t get much airtime on here though

Yes correct. Gem is reportedly to a degree by the pros over in exeter. 16th/18th increasingly looking like a go date for the next bout of cold weather! Lets hope we get the upper air to bring more into the game but with events higher up now pushing very respectable cold over scandinavia and europe i cant see how we wouldnt be!