Model Output Discussion - moving into Winter

[feb1991blizzard]

17 minutes ago, Eastern Scotland WX said:

I’ve never liked the ensemble graphs on Meteociel , prefer Wetterzentrle as you can see clusters.

the full ecm ones do come out on meteociel in an hour, you can see the individual members on the graph.

[Speedbird]

44 minutes ago, Ali1977 said:

Day 10 on the ECM has a dusting of snow in many places, obviously JFF as we’d struggle to get this right at day 2 even!! 

Any chance you could crop the image in such a way that it removes the French but includes us in the Highlands ?

cheers

[Ali1977]

2 minutes ago, Speedbird said:

Any chance you could crop the image in such a way that it removes the French but includes us in the Highlands ?

cheers

This is all it shows sorry  

[Eastern Scotland WX]

5 minutes ago, Speedbird said:

Any chance you could crop the image in such a way that it removes the French but includes us in the Highlands ?

cheers

Here you go

[Speedbird]

Just now, Eastern Scotland WX said:

Here you go

That's great, thanks very much.

Looking good for many of us in the Highlands

[Eastern Scotland WX]

The Met Office 10 day trend will be interesting.

[Mike Poole]

ECM mean, T240:

Now to the clusters, first T120-T168, this is where the issues lie that either permit or forbid the early jackpot solution like the ECM op, but the GFS solution of yesterday doesn’t appear to be represented.

T192-T240:

Strong showing following the op in cluster 1 (22 members), the others seem to leave more wiggle room between the south of the block as coloured, and the UK.  I think I would need to have a look at the individual members, including temperatures before making a call for UK prospects.  And really, the same goes for the T264+ ones, clusters 1 and 3, although cluster 2 looks more clear cut:

Anyway, all remain with Greenland centred block throughout - and that in itself says something.

[Mike Poole]

1 hour ago, John88B said:

The ecm has been very consistent now for a few days whilst the gfs has flapped about.

If the ecm proves correct, which I have a hunch it is, would it be wise to take more notice of the ecm this winter rather than the gfs or does it not work like that?

I'd be interested to see the verification stats of both lately.

Day 5:

Day 10 (perhaps of more interest to us currently) note strong performance of GEM recently:

[Notty]

Does anyone have access to the latest Decider model/graphic that was posted on here recently?

[NewEra21]

While the GFS op wasn't what we want to see, this really isn't a bad set of ensembles. Especially for towards the SE of England.

 

[raul_sbd]

18 minutes ago, Eastern Scotland WX said:

The Met Office 10 day trend will be interesting.

is that on their YT channel? when does it come out?

 

[Eastern Scotland WX]

3 minutes ago, raul_sbd said:

is that on their YT channel? when does it come out?

 

Will be out like early afternoon ish

[SussexSnow]

Oh I've missed the pure adrenalin rush of the rollercoaster ride that is 'Model Output Discussion' in the winter.  Fascinating. 

[TEITS]

The Bullseye over Greenland is all I really need to say today.

I do confess to having mixed feelings though due to knowing the effects this may have on energy bills. Also increasing demand could result in rationing of supplies. The worrying truth is the infamous Greenland blocking set up can be locked in for a very long time. This is especially true if blocking remains and extends into Scandinavia and you end up with alternating spells of E,lys/NE,lys/N,lys.

Let me put it this way. If I was to draw my own synoptic charts for the perfect cold spell in the UK then it would be very close to what the ECM OP/Mean is actually showing. The models will struggle though as they always do when we see the reverse of our normal weather patterns.

[Battleground Snow]

Icon small step to ECM, 00z v 06z

I don't expect GFS to come on board until  tomorrow.

Edited November 30, 2022 by Battleground Snow

[mushymanrob]

12 minutes ago, TEITS said:

The Bullseye over Greenland is all I really need to say today.

I do confess to having mixed feelings though due to knowing the effects this may have on energy bills. Also increasing demand could result in rationing of supplies. The worrying truth is the infamous Greenland blocking set up can be locked in for a very long time. This is especially true if blocking remains and extends into Scandinavia and you end up with alternating spells of E,lys/NE,lys/N,lys.

Let me put it this way. If I was to draw my own synoptic charts for the perfect cold spell in the UK then it would be very close to what the ECM OP/Mean is actually showing. The models will struggle though as they always do when we see the reverse of our normal weather patterns.

Surely that low pressure anomaly is too far North? to me that suggests warm air off the mid atlantic will be drawn up over most of the Country, leaving any wintriness in Scotland ?

[NorthYorksWeather]

ICON 6z only goes out to 120hrs but you can see the PV lobe over the pole primed to head towards Scandinavia. This lobe holds the intense cold air we hope to eventually tap into as the the high to our north moves NW and the cold air is ushered SW towards Blighty as per this mornings EC. 

 

[Singularity]

3 minutes ago, mushymanrob said:

Surely that low pressure anomaly is too far North? to me that suggests warm air off the mid Atlantic will be drawn up over most of the Country, leaving any wintriness in Scotland ?

The 500 hPa anomalies are skewed negative by colder airmasses. With the coldest air being on the north side, that means the surface lows will be further south of the upper trough centres than usual (in any case, surface lows typically travel within the southern flank of troughs and then swing into the centre once matured). 

I'd estimate the polar boundary to be somewhere over the southern half of the UK on that mean.

[andy989]

Great ECM, but I want to see 2 things now. Cross model support and for that support to tick down from day 10

[bluearmy]

8 minutes ago, mushymanrob said:

Surely that low pressure anomaly is too far North? to me that suggests warm air off the mid atlantic will be drawn up over most of the Country, leaving any wintriness in Scotland ?

 

1 minute ago, Singularity said:

The 500 hPa anomalies are skewed negative by colder airmasses. With the coldest air being on the north side, that means the surface lows will be further south of the upper trough centres than usual (in any case, surface lows typically travel within the southern flank of troughs and then swing into the centre once matured). 

I'd estimate the polar boundary to be somewhere over the southern half of the UK on that mean.

The mean is obvs affected by the less cold cluster at a higher latitiude

what we’ve seen on two successive ops is the greeny ridge pushing further se and keeping the Atlantic lw trough further south. 

the eps clusters are improved on yesterdays noon run. Meteociel is frozen on the detailed ens charts which is a pain. 

gfs, gem and icon are all an improvement on yesterday.  The pendulum continues to swing - hopefully those swings get ever smaller. 

[Singularity]

44 minutes ago, mushymanrob said:

Surely that low pressure anomaly is too far North? to me that suggests warm air off the mid atlantic will be drawn up over most of the Country, leaving any wintriness in Scotland ?

Come to think of it, a chart exists that demonstrates what I'm talking about.

As I suspected, mean polar boundary likely somewhere over southern UK (-5°C 850 hPa isotherm is usually a sufficient loose guide).

In fact the mean low pressure axis is arguably through the Channel.

Overall, support from the ECM det. pathway has increased this morning, though it's still not enough to make a confident call in my opinion.

N. Hem views at +144 in order of support level from least to most. Notably, UKM & GEM are very close and GEM goes on to be almost on par with ECM, which suggests that despite not being nearly as advanced with proceedings as ECM at this point, UKM would follow a similar path during the following days.

Typical that the model would chose today to slack off putting out a 00z +168 chart!

Rouge UKM chart removed - thanks to @Blessed Weather

Edited November 30, 2022 by Singularity
Rouge UKM chart removed

[blizzard81]

Gfs op still not coming to the party. However, ecm is holding firm and if anything, it's ens are an improvement too. In fact, this is the best 168hr mean chart of the season so far. 

[Battleground Snow]

Might have to take it back about the GFS not coming on board until tomorrow, big changes as early as 108

Edited November 30, 2022 by Battleground Snow

[Midlands Ice Age]

Whilst we await the 06z, a quick summary of where we are - (for those of less knowledge)

It looks as if we will have an outbreak of cold of some-sorts fired towards Europe  (assuming the more extreme negative -ANO now ruled out).

ECM fires it at the UK...

GEM at the North Sea 

UKMO look as if it will do the same.

JMA fires it at Holland

GFS parra  goes further East, and the GFS looks at Moscow and beyond.

So what  is influencing this?

I think that it is determined by the angle of attack being generated by the 2 anticyclones involved.

1 the Greenland high and 2 the Alaskan ridge which is now shown to be extending into the Arctic.

The pressure being generated between these 2 high pressures will determine where the cold is fired.

(Look above for all the charts>>>>>)

Watch for the angle generated by these 2 major systems.

 

Edited November 30, 2022 by Midlands Ice Age

[feb1991blizzard]

Right onto the next GfS - too late this time but we could play a game every GFS- mark on the map analysis chart where abouts the quasi stationary spoiler low / shortwave will set up.