Model output discussion - Winter has arrived

[mountain shadow]

5 minutes ago, sheikhy said:

Ecm fantastic at 120 hours!!!sliders alert!!

Not sliding into anything that cold though.

At least below average.

[Mike Poole]

Models at T144:

GFS seems on its own here but it has a propensity to blow up lows, the slider solution looks most likely and ECM is the best of the bunch, really good, GEM second.  @chionomaniac - great to see you posting, a sure sign that things are interesting this year?

[Weathizard]

A bit more cold pooling starting to appear to our north east now, nothing dramatic but certainly seems to be improving - if you believe the ECM

[Allseasons-Si]

What's that gate called again...

at 144

Oh!!!,SLIDERGATE

Edited December 5, 2020 by Allseasons-si

[I remember Atlantic 252]

3 minutes ago, TSNWK said:

But are the muddy sliders or icy

hopefully miss my location and stay dry, as will be muddy this time, unlike 3 years ago on the anniversary, much colder air then

[Eskimo]

Here we go! 

Edited December 5, 2020 by Eskimo

[nick sussex]

What drama !

The differences start early . The ECM has two separate upstream lows . The GFS is phasing those at day 4 .

Two clear indicators those lows and the phase point of the UK shortwave and the upstream low . The further south you have the phase the more likely you’ll get a potential slider after that .

Not much support for the ECM op solution however apart from the Arpege . 

 

[Decemberof2010]

ECM and GFS at 144.

 

[Skullzrulerz]

10 minutes ago, sheikhy said:

Ecm fantastic at 120 hours!!!sliders alert!!

Cold rain alert

There's no cold pool

[Catacol]

19 minutes ago, feb1991blizzard said:

Was wondering about this, this is what has lead me to change my winter forecast at the last minute to a cold blocked Feb as opposed to just a cold last dregs late feb into March, but the Nov QBO only reduced from 11 to 10 i think, will it come in time or will just a weakening of westerlies do the trick?, what level of the atmosphere would the E-qbo have to get down to, perhaps not all that low to assist an over the top SSW, also with the nina reducing in intensity we are so close to a GP combination as we are just after solar min now, that should really help shut the jetstream off in February.

It's funny isn't it - how factors can begin to come together so quickly. Nina has begun to fade and the eQBO pop its head up at just the right time when a month ago neither was certain. I have to admit that my grasp of the QBO factor is fairly basic and I couldnt honestly claim to know how far down through the layers we would need the easterly door to open in order to promote maximum wave flux penetration - but it looks to me that it will reach 30hpa by January and I'll take a decent punt that this feels low enough to allow disruptive events to be magnified in January.

Over many years on here I have only felt genuine excitement (as opposed to optimistic hope) a few times. Feb 18 was definitely one. Dec 10 we all got excited even though the longer term prognosis wasnt great. Dec09/Jan 10 was also good. I got duped in Dec 12 - excitement turning to horror. But anyway I'm getting that same excited feeling now. It's early days - it will be a bit of a slow burner - but I can see a genuine chance for more than 1 good wintry spell for the UK this season now. And a properly cold February? I felt this was possible when looking at things pre season. It's a long way out but I'd say we have a growing chance. It's been far too long since we have seen a cold February. Back in the day they were the heartbeat of a UK winter.....

 

Edited December 5, 2020 by Catacol

[chionomaniac]

The trending synoptic pattern is the most important thing here. Try not looking at the 850’s too much until we are far further down the line

[Weathizard]

2 minutes ago, Skullzrulerz said:

Cold rain alert

There's no cold pool

Sliders don’t always require the normal benchmark on cold air to deliver snow fall, we appear to be developing a U.K. cold pool at day 7

[Eskimo]

5 minutes ago, Skullzrulerz said:

Cold rain alert

There's no cold pool

This isn't true, Example: Boxing Day 2017. Here in Brum, we got about 5-6" of snow. 

Edited December 5, 2020 by Eskimo

[Allseasons-Si]

At 168 and the ECM is amplified downstream,things should open up from here IE:-block into Iceland.

[mountain shadow]

1 minute ago, Weathizard said:

Sliders don’t always require the normal benchmark on cold air to deliver snow fall, we appear to be developing a U.K. cold pool at day 7

But look at the warmth being pumped into Eastern Europe from the Mediterranean. That just serves to moderate the air coming from the Arctic.

 

[Sweatyman]

2 minutes ago, Weathizard said:

Sliders don’t always require the normal benchmark on cold air to deliver snow fall, we appear to be developing a U.K. cold pool at day 7

Well said. I hope people take note of this post finally

[Weathizard]

Just now, mountain shadow said:

But look at the warmth being pumped into Eastern Europe from the Mediterranean. That just serves to moderate the air coming from the Arctic.

 

Double edged sword as thats also WAA heading north to support the pressure building to our north east

[jules216]

Poor uppers aside you have got to love this evolution.

 

[chionomaniac]

1 minute ago, mountain shadow said:

But look at the warmth being pumped into Eastern Europe from the Mediterranean. That just serves to moderate the air coming from the Arctic.

 

Or you could look at it another way, -the WAA is perfect for strengthening and reinforcing the eastern block leading to better retrogression and a much better long term outlook

[phil b]

On 02/12/2020 at 11:16, phil b said:

You wouldn't think looking at these charts that you would get any snow but we did in B'ham 18th November 2007

 

 

Edited December 5, 2020 by phil b

[mountain shadow]

Just now, chionomaniac said:

Or you could look at it another way, -the WAA is perfect for strengthening and reinforcing the eastern block leading to better retrogression and a much better long term outlook

Here's hoping Chiono but I'm a jam tomorrow kinda guy.

I always worry that the longer we wait, something comes along to scupper the whole damn thing.

[KTtom]

4 minutes ago, Allseasons-si said:

At 168 and the ECM is amplified downstream,things should open up from here IE:-block into Iceland.

Sorry but untill we get seperation from a Scandi high and the Russian version moves off east to allow the vortex highlighted in your post to move south into eastern Norway, cold yes, but what most are looking for here no.

[JBMWeatherForever]

Seemed strange yesterday when only the GFS was going for a more prolonged colder outlook. If any model was suggesting the return of the Atlantic I would have thought GFS would be it , not the ECM (UK Met is usually  somewhere in between in such battleground situations).   Today it seems to have come back to what I would have expected, but the fact that the GFS has already shown us a colder outlook makes me think all three models will be doing so shortly. 

[chionomaniac]

1 minute ago, mountain shadow said:

Here's hoping Chiono but I'm a jam tomorrow kinda guy.

I always worry that the longer we wait, something comes along to scupper the whole damn thing.

I like more fruit in my jam. I prefer conserve and I am patient enough to hold off on the jam if there is a chance of conserve further down the line....

[winterof79]

16 minutes ago, Skullzrulerz said:

Cold rain alert

There's no cold pool

There wasn't this week but i don't see all who had snow complaining

Edited December 5, 2020 by winterof79