Model output discussion - 5th December 2016 - Into Winter we go

[Man With Beard]

Yes, 2m temps on that Warsaw ensemble chart.

Well it's another exciting morning in the forum. At T240, 10 out of 22 GEFS ensemble members not only maintain strong heights towards Scandi but also develop low heights over C Europe, many forming a cut-off high to our NE. The remainder either keep heights strong to the east without low heights to the south, or (just a few) flatten the pattern slightly bringing something more westerly over most parts. But in general, the GEFS week 2 looking like ECM46 week 2.

But the ECM op is having none of it. It smashes the block out of Scandi in later stages and storms rather than cold would be the buzz word.

Edited December 13, 2016 by Man With Beard

[Man With Beard]

Just one more from me for now - I note the GEFS mean by T192 has shifted the huge high further north, centred over southern Scandinavia at 1035mb

Given the strength of the mean high, I'd imagine the ECM evolution is quite unlikely this morning. 

[mulzy]

2 minutes ago, Man With Beard said:

Just one more from me for now - I note the GEFS mean by T192 has shifted the huge high further north, centred over southern Scandinavia at 1035mb

Given the strength of the mean high, I'd imagine the ECM evolution is quite unlikely this morning. 

Maybe but let's wait for the superior product (the ECM eps) first...

[Polar Maritime]

A few posts have had to go, Please stick to Model Output Discussion only in here.

Please continue, Thanks.

[shaky]

12 minutes ago, Man With Beard said:

Just one more from me for now - I note the GEFS mean by T192 has shifted the huge high further north, centred over southern Scandinavia at 1035mb

Given the strength of the mean high, I'd imagine the ECM evolution is quite unlikely this morning. 

The ecm at 192 hours is not far off that mean chart!!if the high was slightly further north that low out west would have probably disrupted!!expect more changes on the 12z!!

[Blessed Weather]

3 minutes ago, Man With Beard said:

Just one more from me for now - I note the GEFS mean by T192 has shifted the huge high further north, centred over southern Scandinavia at 1035mb

Given the strength of the mean high, I'd imagine the ECM evolution is quite unlikely this morning. 

The latest ECM Weekly thoughts for Weeks 50 to 52 appear to support the GEFS mean. The 2m temp anomaly shows the High likely to be where the GEFS suggests, feeding milder air onto the north Scandinavian coast and something cooler for NW Europe (although the really cold air staying over Russia/Siberia). Precipitation below average throughout for much of NW Europe.

2m Temp Anom:

12-18Dec  19-25Dec  26Dec- 01Jan

Precip Anom:

12-18Dec  19-25Dec  26Dec- 01Jan

 

[jvenge]

51 minutes ago, Seasonality said:

A chilly xmas eve on the 00z. Poor old Father Christmas expecting the usual mild UK mush for a liitle break after he crosses the Atlantic. And for those looking for cold to the east a significant amount of really frigid ensembles appearing for Warsaw. 

 

Hi,

The last few pushes of cold haven't been modeled too well by the GFS so far out. What has happened is that the cold hasn't reached as far north and east, nor has it been modeled in the depth close to accurately. It is good for the general shape and trend, but I wouldn't be at all surprised to see that again further south and not as far east.

 

44 minutes ago, Seasonality said:

Just to add to your comment. In the north of central Europe and in eastern Europe there was only a little 'snap' of mild. Back to average or a touch colder at the surface now.

Quite true. 4 days or so of above average temperatures.

[carinthian]

Take your pick. Assuming 144t is with-in the reliable time span, both GFS and ECM outwardly look similar in their ops . However, ECM is really more progressive to make in roads from the Atlantic. Looks like UKMO chart is more in line with GFS run this morning. The main thing to note is all models show a fall in heights in SW Europe and maintain a strong high pressure zone in Mid -Atlantic keeping the zonal flow out of reach of much of Europe. How the model evolve after that is the question and who is likely to produce the right synoptic for Christmas week ?

 C

Edited December 13, 2016 by carinthian

[Nick F]

UKMO looks a marked improvement pro blocking close to the east compared to 12z run yesterday with more troughing/energy undercutting to the SW - similar to GFS and it looks better in this respect than EC at this timeframe

Quite a few 00z GEFS members have high pressure centre over Scandi at day 8

We are left with an underwhelming 00z EC det. - but is it dealing with the blocking right? It has been the most progressive / keen to blow way the blocking influence over the UK over recent days, despite strong support from GEFS for blocking holding sway, though we have seen the EPS grow support for the blocking over recent runs.

Edited December 13, 2016 by Nick F

[Seasonality]

3 minutes ago, jvenge said:

Hi,

The last few pushes of cold haven't been modeled too well by the GFS so far out. What has happened is that the cold hasn't reached as far north and east, nor has it been modeled in the depth close to accurately. It is good for the general shape and trend, but I wouldn't be at all surprised to see that again further south and not as far east.

 

Quite true. 4 days or so of above average temperatures.

You're right, I'm being optimistic. There has definitely been a trend re: the pulses of cold air. @daz_4 has highlighted this well in a couple of posts. I am heartened by a seasonal feel to the festive period though and also pleased by the increasing presence of lower pressure. Seasonal temperatures at or just below freezing are great but a little snow would be lovely.

PS I think you meant the cold isn't going as far west as predicted by the models, it has even shown as pushing into western Europe but then in reality has dived south into Greece and the Balkans for example.

[carinthian]

19 minutes ago, carinthian said:

Take your pick. Assuming 144t is with-in the reliable time span, both GFS and ECM outwardly look similar in their ops . However, ECM is really more progressive to make in roads from the Atlantic. Looks like UKMO chart is more in line with GFS run this morning. The main thing to note is all models show a fall in heights in SW Europe and maintain a strong high pressure zone in Mid -Atlantic keeping the zonal flow out of reach of much of Europe. How the model evolve after that is the question and who is likely to produce the right synoptic for Christmas week ?

 C

For what is worth the latest UKMO N. Atlantic chart out to 168t shows support for the strength of the block , more in line with the GFS. At the same time ecmwf h res for the same time is much more progressive to make in roads. If I was to make a punt , I would not back the ECM recent outputs.

 C

[West is Best]

56 minutes ago, Man With Beard said:

Just one more from me for now - I note the GEFS mean by T192 has shifted the huge high further north, centred over southern Scandinavia at 1035mb

Given the strength of the mean high, I'd imagine the ECM evolution is quite unlikely this morning. 

Yep this is interesting. That Scandi high is developing as early as T36 which fills me with more optimism. But it's not until c T162 that the reload occurs, aided by the low pressure system developing over Moldova. This helps the high retrogression and unlocks the easterly. Although this later sinks south it's at least something to hang our hopeful hats on.

 

Edited December 13, 2016 by West is Best

[bluearmy]

And yet in he 5/8 day range, the ecm op is generally the better bet 

i imagine we could well be looking at a sinking block for a time and a more zonal period ( nw/se split) before it re amplifies from the west.  May only be a few days 

 note on yesterday's 12z eps, there was a zero percentage chance of getting uppers below -10c into w Europe by end week 2 which makes the meandering cold pool option seem quite a punt.

Edited December 13, 2016 by bluearmy

[jvenge]

27 minutes ago, Seasonality said:

You're right, I'm being optimistic. There has definitely been a trend re: the pulses of cold air. @daz_4 has highlighted this well in a couple of posts. I am heartened by a seasonal feel to the festive period though and also pleased by the increasing presence of lower pressure. Seasonal temperatures at or just below freezing are great but a little snow would be lovely.

PS I think you meant the cold isn't going as far west as predicted by the models, it has even shown as pushing into western Europe but then in reality has dived south into Greece and the Balkans for example.

Yes, that's what I meant. And it has been happening at the 5-6 day range.

[bluearmy]

It's gonna be tough in here when e Europe is under a thick blanket of snow !!

[Blessed Weather]

Matt Hugo comments on the consistency of the GFS ENS and ECM:

[jvenge]

Just now, bluearmy said:

It's gonna be tough in here when e Europe is under a thick blanket of snow !!

Not sure if it will be. There isn't anything to indicate a warm Eastern Europe, for sure, but the precipitation forecasts are showing things to stay quite dry. It won't get above -3 here today, but there are only a few flakes blowing around.

 

[Man With Beard]

ECM mean vs GEFS mean at T192. Big differences for the UK, potentially

  

[feb1991blizzard]

Here she comes.

 

Snow in Murrland at 240.

Edited December 13, 2016 by feb1991blizzard

[Seasonality]

34 minutes ago, jvenge said:

Not sure if it will be. There isn't anything to indicate a warm Eastern Europe, for sure, but the precipitation forecasts are showing things to stay quite dry. It won't get above -3 here today, but there are only a few flakes blowing around.

 

True, no proper snow forecast, yet. Although Poland has already got sprinklings in December and a good dumping at the start of December that I posted about here. https://www.netweather.tv/forum/topic/86370-weather-in-poland/?do=findComment&comment=3486892But with lower pressure starting to appear in the output I'm feeling more optimistic.

 

Edited December 13, 2016 by Seasonality

[Weather-history]

This was ECM ensemble mean 240 hrs ago for today.

 

[Man With Beard]

3 minutes ago, Weather-history said:

This was ECM ensemble mean 240 hrs ago for today.

 

Well, if it moves towards the GEFS again, we'd have to conclude the ECM ensembles are struggling a bit with the set-up. But we'll have to wait another 10 days to find out! I'd be very, very surprised to see the GEFS get a 1035mb mean high that wrong. Never seen it get those wrong before give or take a few hundred miles.

[nick sussex]

Interesting output from the GFS with that shortwave starting off over Finland working its way sw then west and then nw towards the UK with associated colder air.

This is by far the better output because even if the Atlantic does want to make inroads you might get some of the energy going se under any high pressure.

The ECM doesn't do this but takes that shortwave more south, although it does develop some lower heights in the northern Med.

Recent trigger shortwave modelling though doesn't give me much confidence in the GFS solution.  

Recently we had a similar stand off and the GFS overdid the cutback in the jet, we'll see I certainly hope the GFS can come out on top with that shortwave.

[Summer Sun]

Looking through the ECM weekly charts one that caught my eye is for early Jan a noticeable area of below average temps over northern France, Belgium and into Holland

Any sort of SE'ly flow and the SE at least could turn rather chilly

Precipitation remains below average out until Jan 8th at least

[Frank Trough]

29 minutes ago, Man With Beard said:

ECM mean vs GEFS mean at T192. Big differences for the UK, potentially

  

that looks to me like a brilliant example of "tiny Island in the north Atlantic" syndrome. Globally speaking there really are pretty miniscule differences in those two charts but for us on the ground?!