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

[chris55]

No surprises really on GFS 12z op, we are looking at day 9/10 and beyond for the potentially colder scenario to verify. This morning GFS Ensembles clearly highlighted the spread, and Matts tweet this morning showed a 50/50 split from ECM ens.

For me, the 12z ens, tonight's ECM and its ensembles plus the 18z may swing either way. We will just have to wait and see eh.

[Banbury]

Some options in the ENS that we would be more than happy with

[knocker]

48 minutes ago, Ed Stone said:

Agreed, Phil...Even this morning's opening shot (the one that went in off the post) barely grazed the side-netting, on the 12Z...A temporary blip in the overall pattern, perhaps...The Chinese Year of The Slug?

Nah, it's the year of the Squirrel 

Edited December 23, 2016 by knocker

[Purga]

9 minutes ago, Banbury said:

Some options in the ENS that we would be more than happy with

Yes & P17 would do rather nicely

[phil nw.]

Glancing at the gef clusters for day 8 and around  half show a fairly flat Atlantic westerly flow with only 10% going for a direct northerly.

The remaining members are looking at a little ridging with something more north of west. 

http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=euro&MODELL=gefs&MODELLTYP=2&BASE=-&VAR=cslp&HH=204&ZOOM=0&ARCHIV=0&RES=0&WMO=&PERIOD=

Let's see what the ECM run makes of it.

Edited December 23, 2016 by phil nw.
Link added

[chris55]

ECM looking alright at 144, energy pressing on the slug looks to be at a better angle than GFS, should help move it on and allow the ridge behind to build.

Edited December 23, 2016 by chris55

[radiohead]

ECM looking interesting at T168. Let's see where it takes us from here...

Edited December 23, 2016 by radiohead

[I remember Atlantic 252]

2 minutes ago, radiohead said:

ECM looking interesting at T168. Let's see where it takes us from here...

Ay, if you want double digit temps! but yeah agree really, looks like maybe northerly by 1 Jan

[ArHu3]

1 minute ago, radiohead said:

ECM looking interesting at T168. 

It's a slightly flatter version of yesterday but it's still too far away, so still a chance of going back to amplification, though ECMWF rarely goes for more amplification

[northwestsnow]

Not liking ecm at 168, id be suprised if we see a northerly...

[radiohead]

Far better amplification of the 12Z ECM compared to the GFS.

Edited December 23, 2016 by radiohead

[Ice Day]

14 minutes ago, radiohead said:

ECM looking interesting at T168. Let's see where it takes us from here...

Good spot, now looking very interesting at 192 with heights shooting up to Greenland, very like the earlier GFS runs.  Should get a decent northerly from this you would have thought?

Edit, A northerly of sorts by 216 but not looking to last long.  Good to see models still showing disruption in the Atlantic though, hopefully this will bring a much needed pattern change!? 

Edited December 23, 2016 by Ice Day

[chris55]

Those Euro heights are just to stubborn! A more west based evolution but still a variation of the theme. Not to bad TBH at this range..

[radiohead]

A cold end to the 12Z ECM

[booferking]

ECM 168hr primed for a Northerly whats stops it you guessed the slug...

[Matthew.]

The ECM settles for a toppler. Haven't seen Arctic maritime since end of April. Let's hope it can last a day or 2 to get some wintry showers southwards.

[Summer Sun]

A cold start to 2017 according to ECM

[Iceberg]

A very complicated ecm but imho it's probably the best n.hemi I've seen this winter. 

Firstly the high toppling over us. 

Its not going to sink. The higher up 500 charts show a big upper low that's going to stop any sinking. Imho the only real option from there is a rebuild west and another shot at a northerly. 

The polar jet is so fragmented on that run with breakouts all over the place. 

Coupled with the lack of pv on the Atlantic/ us side it would lead to a very interesting Jan. Let alone giving us cold etc for the first couple of days. 

Bug thumbs up from me. 

[knocker]

51 minutes ago, Iceberg said:

A very complicated ecm but imho it's probably the best n.hemi I've seen this winter. 

Firstly the high toppling over us. 

Its not going to sink. The higher up 500 charts show a big upper low that's going to stop any sinking. Imho the only real option from there is a rebuild west and another shot at a northerly. 

 

I'm sorry I haven't a clue what you mean by that, could you clarify please. To be more specific where is this big upper low situated and why is going to stop the progression south east that the previous bout of ridging followed? I'm taking a punt and thinking it maybe the trough to the east extending an arm south west to phase with the cut off upper low off the coast of North Africa, which would do the trick, but it's a big stretch to arrive at that.

Edited December 23, 2016 by knocker

[BLAST FROM THE PAST]

1 hour ago, radiohead said:

Far better amplification of the 12Z ECM compared to the GFS.

Look at the heights over Europe....that is screaming of flattening out.  No decent northerly from that position. Toppler and HP ringing over likely. That is just my reading of the model run, nothing more.

 

BFTP

[-uksnow-]

UKMO goes the way of the ECM, more amplified than the GFS - this is far from resolved yet, I think it'll be tomorrow night or christmas day before we know how the low in the atlantic will behave.

[I remember Atlantic 252]

Just now, -uksnow- said:

UKMO goes the way of the ECM, more amplified than the GFS - this is far from resolved yet, I think it'll be tomorrow night or christmas day before we know how the low in the atlantic will behave.

Then we'll get, models inaccurate because of missing data over Xmas 

[bluearmy]

4 minutes ago, knocker said:

I'm sorry I haven't a clue what you mean by that, could you clarify please. To be more specific where is this big upper low situated and why is going to stop the progression south east that the previous bout of ridging followed?

Assume ice means the Azores upper low will stop the mid Atlantic upper ridge from sinking south

what happens to the surface features is another matter !!

 

 

 

[-uksnow-]

Just now, I remember Atlantic 252 said:

Then we'll get, models inaccurate because of missing data over Xmas 

Please not that saga again! We shall see.

[Iceberg]

5 minutes ago, knocker said:

I'm sorry I haven't a clue what you mean by that, could you clarify please. To be more specific where is this big upper low situated and why is going to stop the progression south east that the previous bout of ridging followed?

25w 30n on the 500 ecmwf.int chart