Model Output Discussion - Winter arrives

[bobbydog]

Hmm... 

A little too much desperation in here on only day 5 of winter. December snow is fairly rare, yet a few people have already had a decent amount. Some of the most memorable snowy winters didn't get going until January or even February. Even the famous '62-'63 winter started its main event on boxing day, currently outside of the range of the models...

Anyway, the GFS is throwing up some far from "uninteresting" scenarios.

This storm we are expecting in a couple of days looks impressive on this chart-

this is the wind gust chart for the same time-

further on at 216 hrs (probably too far out to be accurate anyway), this chart looks fairly unimpressive for most of the UK-

However, this is what that would translate to- 

Anyway, I'm certainly not giving up on winter yet... 

[Atmogenic]

2 hours ago, Ed Stone said:

Gordon Bennett -- it's Hobson's Choice! it's either anticyclonic gloom or (should the sun deign to appear) 15C and springlike?

    

I'll take that please 

[Lukesluckybunch]

20 minutes ago, LRD said:

From your posts, which essentially are saying the same thing over and over again but in a different way, I get the sense you're getting a bit frustrated mate. If that's the case (and you're not being a low-level WUM), can I give you some friendly advice? I'd perhaps give this weather watching lark and this forum a bit of a rest for a few days because what is being churned out by the op runs of ECM, GFS et al ain't going to improve in the next 3 or 4 days... and, who knows, they might not improve at all if it's winter you're after. It's what I tend to do when the short/mid term outlook is looking a bit uninteresting for my tastes. I take a break and then come back to it after 3 or 4 day

I was only saying on what I want the charts to be showing that all.I'm not frustrated or anything like that.sorry if you took me the wrong way LRD

[Dancerwithwings]

Let’s hopey poos that pert 3 is something that’ll be In place for us coldies, okay it’s right at the death of the run, but my glass is always full

Edited December 5, 2021 by Dancerwithwings

[MATTWOLVES 3]

37 minutes ago, Lukesluckybunch said:

let's hope something starts to appear,as December could quickly become a right off! And we don't want that continuing into january!

When in doubt do what I do...Start talking to fairies and writing your Xmas wish list to santa...

Sorry folks I'm in a daft mood.

Quick mention on the ens from the 12z...a growing cluster of colder runs after this milder affair towards next weekend...im thinking 7 days before it becomes colder..also growing number of ens bringing a rise in pressure! 

Yeh pretty poor at the moment...I think I need a break from model watching....catch you all after Xmas...ohh hang on a sec its EC46 tomorrow...catch you on Monday then

Enjoy it if you can.

[snowhope]

Pretty sure snow in March or April is more likely than December!

[Lukesluckybunch]

1 minute ago, snowhope said:

Pretty sure snow in March or April is more likely than December!

Which I can't really get my head around,because December is a winter month!

[bobbydog]

2 minutes ago, snowhope said:

Pretty sure snow in March or April is more likely than December!

Probably... but it's also much more likely in January or February... 

[Cheshire Freeze]

On 05/12/2021 at 19:47, snowhope said:

Pretty sure snow in March or April is more likely than December!

A lot less likely to stick around away from some decent elevation though. 

Now until around 10th Jan is the optimal period for snow sticking around all day

[LRD]

2 minutes ago, Lukesluckybunch said:

I was only saying on what I want the charts to be showing that all.I'm not frustrated or anything like that.sorry if you took me the wrong way LRD

But the charts aren't going to be showing cold and snow (which is what I presume you want) for a few days yet (if they do at all). There are some emerging signs and hints of 'proper winter' in the longer term (12-15 days from now) but if you want the op runs to show that right now I think you're going to be disappointed for the next few days... at least. Hence my friendly advice to take a step back for a bit and relax if it's getting you down a bit

I think the action is going to be on the short term thread, over the next 2-3 days, with some transient snow (for hills and mountains, not for Bicester or where I am I'm afraid) and a potentially strong wind and rainstorm midweek

[I remember Atlantic 252]

3 minutes ago, Lukesluckybunch said:

Which I can't really get my head around,because December is a winter month!

Dec is the most Atlantic dominated month of the year! snow tends to only be on northern hills

[Mike Poole]

9 minutes ago, bobbydog said:

Hmm... 

A little too much desperation in here on only day 5 of winter. December snow is fairly rare, yet a few people have already had a decent amount. Some of the most memorable snowy winters didn't get going until January or even February. Even the famous '62-'63 winter started its main event on boxing day, currently outside of the range of the models...

Anyway, the GFS is throwing up some far from "uninteresting" scenarios.

This storm we are expecting in a couple of days looks impressive on this chart-

this is the wind gust chart for the same time-

further on at 216 hrs (probably too far out to be accurate anyway), this chart looks fairly unimpressive for most of the UK-

However, this is what that would translate to- 

Anyway, I'm certainly not giving up on winter yet... 

Agree there, far too much giving up the ghost on here and it is only 5 Dec!

Anyway, the ECM clusters.  As I said earlier, apart from the obvious near term impact of the storm, other shorter range models are available for that, my interest on ECM and ensembles is on how the remnants of the storm depart the UK.  Here T72-T96:

And it is the T84 chart that is telling in this respect, with cluster 1 holding some interest for back edge snow as it exits SE.  All the other clusters have it fill in place.  The op is in cluster 3.  

T120-T168 - forget it, all +NAO.

T192-T240:

All show a rise of heights into Scandi, cluster 3 the most prominent, indeed - it gets the red border.

T264+

All 5 seem to suggest some sort of blocking to our NE by this point, MJO phase 7 kicking in by now?  We will see…

[Mapantz]

This thread is for model discussion.

Moaning about the weather or the models, or just general chat can be done over here

[NewEra21]

All I'm really looking for now is just high pressure taking over us or in our vicinity. And then just seeing if we can hopefully see it move into a more favourable position for something colder down the line.

But either way we're going to have to go through a mild spell to get to that position. The next 2 weeks aren't going to be pretty, I'm just looking for baby steps for hopefully later in the month.

[MJB]

1 minute ago, NewEra21 said:

All I'm really looking for now is just high pressure taking over us or in our vicinity. And then just seeing if we can hopefully see it move into a more favourable position for something colder down the line.

But either way we're going to have to go through a mild spell to get to that position. The next 2 weeks aren't going to be pretty, I'm just looking for baby steps for hopefully later in the month.

Yes me too , HP near or over us is a good start IMO .

[Methuselah]

Well peeps, I can't see anything in current model-output that suggests we're in for another boring, miserable and mild zonal winter. We just have to take what we get, whatever it's like. I mean, there's always 2023?

[Mike Poole]

It’s 5 days into winter, and already it feels like we need a pause and re-take of where we are headed.  First storm Barra, some in the north could see snow from this, down south it looks like it won’t be exceptional wind wise, but I’m mindful of those runs that have it clearing to the SE, possible wintry mix on the back edge there.  If it does clear SE it might have implications on how we think about the next one (there is a next one!) and we might expect the nascent wedge to our NE to put up more of a fight.

Beyond that, all the models suggest an Atlantic dominated week (I’m still not 100% sure), but it looks like some mobility is inevitable.  

One question in my mind, is how coupled are the strat and the trop PV?  NAM index (0z GFS

Well they are certainly flirting!  Maybe twice, but the end of the run maybe suggests it wasn’t to be.  And there may be a lot of reasons for that, but a strong signal in the trop in couple of weeks could be the reason, like the MJO phase 7.  The strat vortex is spinning very fast at the moment:

 

So if they do fully couple, that could be badissimo…but it makes it harder for them to do so, so some pressure from a pattern in the trop at this stage could really help keep them apart.  

And the ensembles seem to be keen on a ridge to our NE, ECM eps Z500 anomaly at T240:

Whatever it means down here it should put pressure on the strat vortex, and with it spinning so fast, if it falls, it could be cataclysmic.  Also GEFS chart T384:

 

What interests me on this one, apart from the NE block, is the Aleutian high.  @Nick F referred to this in his winter forecast, and it seems there in the models now, and there may be a gap in my knowledge here, because I thought a Russian high and Aleutian low was the best pattern to put pressure on the vortex.  Nick, or anyone else, if you could help with my understanding here, please?  

Anyway, lots going on so let’s keep the toys in the pram, or, even better, in the toy shop, for now….

Edited December 5, 2021 by Mike Poole

[Updated_Weather]

Think people need to relax it’s only 5th December and people are already calling it.. seriously? Even the weather itself hasn’t decided what it’ll do? 
the models can’t even agree on the path of this low and it’s only 2/3 days away!

a lot of factors are at play and NO model will at all give any indication at this stage I assure you. Everything is JFF imo - a lot can change at short notice.. I guess people forget that.

[Cheshire Freeze]

@Mike Poole The Siberian/Russian HP and Aleutian LP  is the optimal set up to induce a SSW...you're not wrong on that.

That's why I made mention 6 weeks or so back that I couldn't see where the Aleutian LP signal was coming from. We've seen sparse hints here and there of an optimal pattern to drive a SSW but a mid winter event looks unlikely to me and has for some time.

Edited December 5, 2021 by CreweCold

[Mike Poole]

1 minute ago, CreweCold said:

@Mike Poole The Siberian/Russian HP and Aleutian LP  is the optimal set up to induce a SSW...you're not wrong on that.

That's why I made mention 6 weeks or so back that I couldn't see where the Aleutian LP signal was coming from. We've seen sparse hints here and there of an optimal pattern to drive a SSW but a mid winter event looks unlikely to me and has for some time.

Thanks CC, I do remember you saying that.  

[Lukesluckybunch]

1 hour ago, LRD said:

But the charts aren't going to be showing cold and snow (which is what I presume you want) for a few days yet (if they do at all). There are some emerging signs and hints of 'proper winter' in the longer term (12-15 days from now) but if you want the op runs to show that right now I think you're going to be disappointed for the next few days... at least. Hence my friendly advice to take a step back for a bit and relax if it's getting you down a bit

I think the action is going to be on the short term thread, over the next 2-3 days, with some transient snow (for hills and mountains, not for Bicester or where I am I'm afraid) and a potentially strong wind and rainstorm midweek

That's right I can see things being potentially stormy tues/weds.and yes it's a a couple of days cold this week Thursday Friday as the low moves through and the winds vear easterly behind it for a short time.

[Lukesluckybunch]

1 hour ago, I remember Atlantic 252 said:

Dec is the most Atlantic dominated month of the year! snow tends to only be on northern hills

Oh ok I didn't know that thanks.I always feel that February is pretty good for some proper cold

[Mike Poole]

Well a surprise on the ICON 18z, T90:

The storm remnants move SE, and there’s some marginal air there!

T120, wasn’t expecting this much resistance from any block this early:

[sheikhy]

1 minute ago, Mike Poole said:

Well a surprise on the ICON 18z, T90:

The storm remnants move SE, and there’s some marginal air there!

T120, wasn’t expecting this much resistance from any block this early:

Yup was watching the icon as it was updating!!need to see more of the same from gfs 18z!!

[sheikhy]

Here we go!!cmon 18z give us an early norwegian wedge!!!!❄!!!