Model Output Discussion - cold spell to end Autumn

[Daniel*]

9 minutes ago, northwestsnow said:

cheers feb, hope your right- although the info from TWO suggests lots of cold hard rain..

It doesn’t quite matter what it is showing it will change again and again. Midlands north look to remain on the right side of the cold boundary so no real concern more iffy further S.

[Team Jo]

It’s one run. Let’s all just keep calm! Discussion around what’s happening on TWO is mudtracking out of context commentary in here, if you were a complete novice like many new people just guests browsing on here are the last three pages make very little sense. GFS amazing, slider on slider off, ECM rain. All offer a variation on a theme. 

look at the trend and compare like for like. Don’t panic! It’s too early for shouting.

Edited December 5, 2017 by Team Jo

[Daniel*]

I’m sure if I looked at EC snow charts there would be decent snowfall for some in Midlands northwards largely wet S of the M4 even this bad outcome will produce for some in the north. 

D10 on ECM ends on an intriguing, very cold, note.

[nick sussex]

Well good and bad news this morning!

The ECM isn't interested in the favourable early slider however its later output is an upgrade compared to last night.

The GFS delivers a couple of sliders and not as good as the ECM later.

The UKMO looks a bit washed out upstream at T144hrs in terms of lack of shortwave development upstream and flatter at that point but somehow grabs victory from the jaws of defeat at T168hrs with the jet running south of the UK with another slider at that point.

In terms of overall pattern little change positive PNA still there but the broad trough ridge pattern belies the uncertainty over the UK.

Overall the NH pattern continues to look favourable for the UK to see further cold and snow. Its a pattern where you need some luck because the dividing line between cold and less cold is small on a global scale.

Expectations can sometimes ride ahead of the type of set up, its not one which you can guarantee non-stop cold but it is one where you have chances for periods of cold and snow if that makes sense.

[Severe Siberian icy blast]

3 minutes ago, Team Jo said:

It’s one run. Let’s all just keep calm! Discussion around what’s happening on TWO is mudtracking out of context commentary in here, if you were a complete novice like many new people just guests browsing on here are the last three pages make very little sense. GFS amazing, slider on slider off, ECM rain. All offer a variation on a theme. 

look at the trend and compare like for like. Don’t panic! It’s too early for shouting.

Completely agree, I got up at 6:30 and different people shouting very contradicting opinions on every single hour that came out as the models updated, I gave up and just looked for myself, but a tad frustrating it has to be said,  why not allow for the entire period in question to come out and look across a suit to compare and try to inject a balance, and if can't then wait for more experienced ones to comment because this forum is viewed by professionals around the world and it's nice to try to uphold netweathers reputation as one of the best out there . . . 

[bluearmy]

22 minutes ago, northwestsnow said:

Anyway- lets see what the EC ens show..

Less snowy than previous run (especially further south) although ok n midlands north 

next amplification days 9/10 have good mean agreement and look to be more sharp re the jet than previous so potentially colder 

later on I think we have variation in the clusters which delivers a flatter mean than is probably likely - wait for the clusters to confirm this 

Edited December 5, 2017 by bluearmy

[terrier]

Well looking at the big 3 models this morning it seems we could be heading for a half way house as often is the case. Think regarding the snow potential into early part of next week we will see more in the way of wet than white. Even further north any snow soon turning back to rain. Unless your in the far north. But as ever more runs needed. 

[Summer Sun]

ECM op and mean pretty close this morning

[Snowy L]

44 minutes ago, Surrey said:

We got this starring us in the face, think we should get over this first before looking ahead.. 

 

2016

 

2015

2014

N/A

2013

Closet is 2012.. Even then not even as potent.

 

 

Incredible stuff so early on in winter comparing the last few years. Shows how potent this cold spell will be

Exactly, compared to the last few years. 5c would be incredible stuff compared to the last 4 winters. They have really made us forget what a typical winter should be like. A 3-4 day northerly is nothing out of the ordinary.

[Captain Shortwave]

The issue at the moment regarding Sunday onwards is whether we see a weak high develop to our north and the approaching Atlantic low moves towards us, if we see warm air advection get over the top of this low (The slider option), then many places could see snow depending on the track. The trouble is are we seeing the models showing phantom heights to our north? If they are then we could very well see a the models all moving to the same solution rather quickly and that could very well be a track which takes the low east through Scotland with the potential for a lot of rain and gales with some very low heights across the UK.

High stakes game this is, no higher heights then the low simply will not slide and will instead track roughly eastwards through Scotland but ultimately we see a mild sector with the maritime air pushing the cold air away. If we do get a wedge of heights then the low will disrupt and move south east into the base of the Euro trough whichwould be the snowy solution. Frankly the mornings output ranges from the potential for large amounts of snow to solutions with the potential for large rainfall totals and the risk of very strong winds if that Atlantic low is allowed to move towards us without any means of weakening it (trough disruption).

Longer term the ECM looks decent at keeping us at below or even well below average in terms of temperature with the Atlantic ridge/Euro trough waxing and waning but ultimately the long wave pattern looks fairly fixed so I suspect this will it/won't it snow question will keep rumbling on into the coming weeks.

      

No sign of a break to a milder pattern or to a properly blocked pattern just yet......

I guess as the old saying goes, we at least have a ticket in the raffle here.

The differences in the 850s from the initial cold plunge are still there this morning as well. A lot to be resolved.

[karlos1983]

ECM is a worry

UKMO at 168 makes we worry a little less

GFS is a southern dream 

Edited December 5, 2017 by karlos1983

[northwestsnow]

1 minute ago, karlos1983 said:

ECM is a worry

UKMO at 168 makes we worry a little less

Looks a corker that - hope EC is wrong!!

[karlos1983]

Just now, northwestsnow said:

Looks a corker that - hope EC is wrong!!

Yeah, i think by this evening or certainly tomorrow morning, we will know which ones been wrong. Of course I hope it’s the ecm, but..... it’s the ecm. So I’m on the fence big time until I see compelling evidence to convince me otherwise. UKMO wouldn’t be such a bad middle ground imo. 

[I remember Atlantic 252]

2 minutes ago, northwestsnow said:

Looks a corker that - hope EC is wrong!!

Doubt EC will be wrong, experts on here, model thread says it's the best, stats prove it? so game over for the south unless EC backtracks, the low is further east than the 12Z

GFS though has sliders too far west, need a middle ground

[Frosty.]

The Gfs 00z is a beauty, major cold spell, ice days, snow showers and even a snow event or two..yes please!

[karlos1983]

1 minute ago, I remember Atlantic 252 said:

Doubt EC will be wrong, experts on here, model thread says it's the best, stats prove it? so game over for the south unless EC backtracks, the low is further east than the 12Z

GFS though has sliders too far west, need a middle ground

I’m sorry but to any newcomers that’s just completely misleading. 

When we have the “big three” all Showing a different route at D6, you can’t say the EC will be right, also I’ve not heard anyone saying EC will be correct, apart from your comment

there is worry because the EC has been so reluctant to show the low slide further west, but that’s it.

all to play for

 

[captaincroc]

3 minutes ago, I remember Atlantic 252 said:

Doubt EC will be wrong, experts on here, model thread says it's the best, stats prove it? so game over for the south unless EC backtracks, the low is further east than the 12Z

GFS though has sliders too far west, need a middle ground

To be honest the ECM could be wrong as it has been before but you're right it is one that isn't to be bet against lightly.  I do feel slightly more apprehensive than I did last night due to the ECM becoming more marginal but we have lots of fun and games until it's sorted and 'sliders' will never please everyone. I personally just want the cold to last - rather than intermittent - so I would favour the GFS outcome for sure. 

Maybe the experts could refresh us on how sliders are modelled in regards to their biases? This might give us a hint of what to expect in a few days? 

[I remember Atlantic 252]

1 minute ago, karlos1983 said:

I’m sorry but to any newcomers that’s just completely misleading. 

When we have the “big three” all Showing a different route at D6, you can’t say the EC will be right, also I’ve not heard anyone saying EC will be correct, apart from your comment

there is worry because the EC has been so reluctant to show the low slide further west, but that’s it.

all to play for

 

Sure I've read on here EC has the best verification  stats? not sure at which range mind, GFS not rated by many on here

[BurwellWeatherWatch]

3 minutes ago, karlos1983 said:

I’m sorry but to any newcomers that’s just completely misleading. 

When we have the “big three” all Showing a different route at D6, you can’t say the EC will be right, also I’ve not heard anyone saying EC will be correct, apart from your comment

there is worry because the EC has been so reluctant to show the low slide further west, but that’s it.

all to play for

 

yes it was very misleading - but i suspect more for the purpose of attracting attention rather than in respect of being scientific or analytical. In these situations where you have a range of solutions at relatively close range, it normally seems best to assume the middle ground between them will probably play out. That normally tends to be dull/non-descript but in this case could be rather good??

[Chesil View]

Just now, I remember Atlantic 252 said:

Sure I've read on here EC has the best verification  stats? not sure at which range mind, GFS not rated by many on here

That may be so but that doesn't mean its right all the time in every corner of the world at six days out infact I would wager that at six days the model verification stats for all models are quite low and fairly closely grouped.

Plus we're at the time of year when the ECM throws out its yearly complete balls up chart. Remember THAT ECM in Dec 2012 and the 51 ensemble members going coldfiasco last December.

Edited December 5, 2017 by Broadmayne blizzard

[snowblizzard]

14 minutes ago, Frosty. said:

The Gfs 00z is a beauty, major cold spell, ice days, snow showers and even a snow event or two..yes please!

Surely, much too marginal (cold rain/sleet) for us in the South?

[BLAST FROM THE PAST]

29 minutes ago, karlos1983 said:

ECM is a worry

UKMO at 168 makes we worry a little less

GFS is a southern dream 

How is the ECM a worry?  Very cold air with LPs moving in on NW/SE axis hitting that cold air then (as hoped/anticipated at mid month) an Atlantic ridge re-establishing with deep LP to E/NE flooding yet more cold air south at end of run.  Smaller Detail will change but the theme is great.

By Sunday / Monday very much every chance the south will be in the party if runs remain as they are

 

 

BFTP

Edited December 5, 2017 by BLAST FROM THE PAST

[karlos1983]

9 minutes ago, BLAST FROM THE PAST said:

How is the ECM a worry?  Very cold air with LPs moving in on NW/SE axis hitting that cold air then (as hoped/anticipated at mid month) an Atlantic ridge re-establishing with deep LP to E/NE flooding yet more cold air south at end of run.  Smaller Detail will change but the theme is great.

 

BFTP

Completely agree.

Edited December 5, 2017 by karlos1983

[BLAST FROM THE PAST]

4 minutes ago, karlos1983 said:

Completely agree, I was just talking about the initial slider low that was being referred to. I’ve been around long enough to know the ecm and just about every other model is showing fantastic winter prospects going forward.  it’s all good

Unfortunately these slider lows are always a gamble aren’t they as milder air mixes in.  A gamble worth having though

 

BFTP

[karlos1983]

1 minute ago, BLAST FROM THE PAST said:

Unfortunately these slider lows are always a gamble aren’t they as milder air mixes in.  A gamble worth having though

 

BFTP

Completely agree. But ECM always a worry when not on board. Not to say it’s right. All to play for. And I’m talking  about the slider low, not the D10 or mid to long term prospects.

mis-read your orginal post, apologies for that. So have re-written it.