Model output discussion - Jan 3rd onwards

[ScottSnow]

2 minutes ago, SLEETY said:

Who cares,the credibility of EC 46 is through the floor anyway ,never correct,and we have just seen the latter stage of ecm run up to day 10 be  also useless after weather history posted the actual for today compared to 10 days ago.

I still think there is potential in the models and looking at the GFS average it keeps the Scandy trough throughout and I think northern areas will likely hang onto to the colder weather. Certainly the higher areas of the north east where I live have had snow since before  Xmas.
The Met Office update from today looks like they are going for a cold end to the month maybe taking into the effect the SSW.

Just going from experience usually we see patterns repeat and hopefully we will see the current patterns repeat but with a colder feed

[Singularity]

36 minutes ago, Tim Bland said:

EPS confident of a return to average next week

Couldn't let this one slip through - you can't call a projection confident that has the 25th percentile 4 or 5°C lower than the 75th percentile, as is the case for the maximum in the later stages.

There's a general sense that the models are in a state of flux at the moment regarding what goes on after about a week from now, beyond a broad signal for high pressure near or over the UK in 8-10 days time (which is a typical La Nina pattern during times of reduced zonal flow).

Worth bearing in mind that any significant errors in resolving the SSW propagation downward within the near term will skew entire ensemble suits going forward.

I've not been calling for any major cold spells to take place this month but have always considered it a possibility given the stratospheric events. This hasn't changed.

[chris55]

53 minutes ago, sebastiaan1973 said:

Latest EC46

ECMWF | Charts

APPS.ECMWF.INT

 

The signal here is very diffuse towards the end of the month. If anything it’s suggesting a southern jet stream on the last frame.Aka 1947 ️

[Battleground Snow]

Icon at 120. Deeper Iberian low, but not much change compared to 12z

 

[chris55]

13 minutes ago, Mr Frost said:

I don’t blame you for not being optimistic mate - especially living in one of the flattest countries on Earth.

We could all be sunbathing by the end of January and through February if these charts below become reality. 

Latest ECM Monthly Temperature (T2m) Anomalies.

Weekly breakdown below:

04/01 to 10/01

11/01 to 17/01

 

18/01 to 24/01

 

25/01 to 31/01

 

01/02 to 07/02

 

08/02 to 14/02

Interesting run for sure though from an above average outlook perspective!

We all know how quickly these can flip - cold/snow lovers no need to panic. 

Fascinating model/chart/teleconnections viewing at the moment - loads to view and discuss! Great stuff! 

Interesting to see Greenland/Iceland BELOW average throughout. That suggest a southern jet (as previous post) with the lack of a strong TPV over Greenland. 
 

The plot thickens. 

[Weather-history]

26 minutes ago, Jason M said:

Pretty good effort by the GFS I'd say

 

Just looked at the other GFS runs for that day, not sure I agree with it being  a pretty good effort. I think the comment would be justified if it was broadly across all runs that day . Anyway for what its worth

0z 

and the 06z run

and the 18z run

 

[bluearmy]

3 minutes ago, chris55 said:

Interesting to see Greenland/Iceland BELOW average throughout. That suggest a southern jet (as previous post) with the lack of a strong TPV over Greenland. 
 

The plot thickens. 

I dont quite follow the logic but the likelihood of an upper ridge around greeny persists in the clusters on the 46. But the jet runs below ...... unconvincing but not a good update .....

[Scott Ingham]

18 minutes ago, Singularity said:

Couldn't let this one slip through - you can't call a projection confident that has the 25th percentile 4 or 5°C lower than the 75th percentile, as is the case for the maximum in the later stages.

There's a general sense that the models are in a state of flux at the moment regarding what goes on after about a week from now, beyond a broad signal for high pressure near or over the UK in 8-10 days time (which is a typical La Nina pattern during times of reduced zonal flow).

Worth bearing in mind that any significant errors in resolving the SSW propagation downward within the near term will skew entire ensemble suits going forward.

I've not been calling for any major cold spells to take place this month but have always considered it a possibility given the stratospheric events. This hasn't changed.

Yeah them percentiles scream uncertainty mathematically

[Daniel*]

Just now, steveinsussex said:

So the murmers on Twitter are that the ssw may actually not impact our weather as much as first thought....

That is based upon the GFS 12z alone for that matter ECM has continued to be more ‘coupley’ the GFS has hardly handled stratosphere great in recent times. 

[MAF]

4 minutes ago, steveinsussex said:

So the murmers on Twitter are that the ssw may actually not impact our weather as much as first thought....

but its not a surprise, the SSW may give a chance of change, then again it could do nothing to change. lots of other factors to take into consideration. the biggest one is that i have seen no cooling down from the east of UK to help any SSW proliferate

Edited January 4, 2021 by MAF

[Mapantz]

A bunch of posts hidden as it's either moaning or just general chit-chat. 

Please use this thread for that:

Thank you.

[Mike Poole]

1 hour ago, sebastiaan1973 said:

This doesn't reflect a SSW we want to see. Just look how small negative NAO is.

It’s a model, albeit a lower resolution one (I believe) than the ops, so if all models are struggling, I can see no reason why this one would be any better, and several why it may be a lot worse, on the cusp of a SSW.

Also, taken at face value, in the depth of winter any regime other than +NAO can hold promise, and that is diminishing rapidly into Feb!

Edited January 4, 2021 by Mike Poole

[IDO]

5 minutes ago, steveinsussex said:

So the murmers on Twitter are that the ssw may actually not impact our weather as much as first thought....

...it is complicated, but I would expect some colder shots at least even in the worse case scenario. The BFTE is what is up for grabs and that maybe less likely. Greenland blocking is my call if we do get a good coupling. We should know more by next week...

[Guest]

Typically, doesn't an SSW move or amplify the the polar vortex into north America, bringing deep cold to low latitudes in central areas? That's being depicted in the models now in thier later frames. So if that's a given we can only hope it central and not eastern cold otherwise it'll fire up the Atlantic and the UK would have zonal for a while at least....

[SMU]

GFS Moves to UKMO as it transfers more energy northwards over France @96

[TSNWK]

1 minute ago, Steve Murr said:

GFS Moves to UKMO as it transfers more energy northwards over France @96

Good.. personally I'm done with heights into Greenland and drooping low thing for the weekend too inconsistent..

I mused early on I preferred UKM.. would be darn cold at the surface at the end and NH was ripe for picking..

[frosty ground]

Not sure there is much difference between the 12z 18z 

 

 

[Man With Beard]

Pub run has been a blast in recent days and I sense another stinker coming. Trigger low moving in for D6 

 

[Griff]

108 gfs and p

My head hurts from model fatigue, home school shock, and an unwanted football result... 

In other words I can't see this going well. 

[Griff]

Maybe just maybe 

[MKN]

4 minutes ago, Griff said:

Maybe just maybe 

Either way it goes from here the GFS is certainly the most promising for prolonging the cold spell.

Edited January 4, 2021 by MKN

[Griff]

2 minutes ago, MKN said:

Either way it goes from here the GFS is certainly the most promising for prolonging the cold spell.

GFSP has similar ideas

 

[Mike Poole]

ECM mean, spread and clusters from 12z:

Points to note:

• Trop vortex (T240) still other side of the globe, only question whether it travels west or east towards us!!
• Mean plot disguises a lot of uncertainty in all sorts of weird places, but since the run up the downstream/easterly upstream component has looked large.  
• No return to westerly Atlantic on the clusters, any of them (T192-T240), cluster 2 looks particularly strong on blocking moving from below Greenland to scandi, I think we should look out for this one.  

SSW day tomorrow:

Maybe a bit of a double dip, but not back into significant westerlies for at least two weeks, that’s from Stratobserve, so GFS, GEM + ensembles.  

So where now?  Let’s consider 2 previous events, 2013 SSW happened about the same time, lead to a week of snow about 2 weeks after, that’s all, and then there was that serious cold spell in March, attributable to the same event.  2018, happened later in Feb, and we had the true BFTE going into March.  I think there is no way there is enough oomph in the Atlantic currently to stop a reversal of winds if the fallout from the SSW is favourable, or even nearly favourable.  So, I’m still gunning for either the full BFTE or a highly blocked scenario giving maybe more limited opportunities for snow.  The idea that the Atlantic will be steaming ahead in a couple of weeks is for the birds, what’s to drive it, given there’s nothing now?

Might start commenting on individual runs again tomorrow .

Edited January 4, 2021 by Mike Poole

[Griff]

GFSP at 168 signs of amplification ooop north

 

[winterof79]

8 minutes ago, MKN said:

Either way it goes from here the GFS is certainly the most promising for prolonging the cold spell.

What cold spell. It hasn't happened.