Model Output Discussion 29th December - Into mid-Winter.

[snowbob]

8 minutes ago, booferking said:

Hot of the press.

Wow full house then

surely ecm consistency for the last few days has got to be sniffing something correctly.

the world of model reading is fascinating. Would love gfs 6z to smell the coffee.

 

Edited January 10, 2017 by snowbob

[Met4Cast]

I cannot see all 51 ECM Ensembles having the wrong signal here. I just can't. Has there ever been a situation where an entire 51 member suite backtracked? I'd say it's game on. 6z in an hours time will complete the backtrack and show the full blown Easterly the ECM has been showing for days now.

[Johnp]

12 minutes ago, knocker said:

I would think that a fair call. Regarding the EPS means this morning predictable thay do not follow the det. run with the extensive ridging and the movement north of the upper low to the SSE. Thus the high pressure centre remains to the south west and the cold easterlies are further south over central and eastern France. This portends a transition to a more W/SW regime over the UK as has been indicated by the anomalies

That's not what Matt Hugo is saying?

[Summer Sun]

UKMO extended (t168)

High pressure back over the UK and dry for most

Edited January 10, 2017 by Summer Sun

[Ali1977]

With regards the Scandy block and all members showing it, the Op wasn't a proper Scandy block and we only had a very cold slack flow - which is great but we aren't talking a very snowy one just yet.  Maybe EC clusters give a better idea on this.

[Johnp]

5 minutes ago, snowbob said:

Wow full house then

surely ecm consistency for the last few days has got to be sniffing something correctly.

the world of model reading is fascinating. Would love gfs 6z to smell the coffee.

 

But if you read what Knocker has written, how can all 51 members be in agreement?

[Paul_1978]

7 minutes ago, Chris.R said:

I think it's ON! 

 

He also tweeted that the GEFS (ens) aren't having it. So which model is right? One of these days we'll get a concensus across the board!

[winterof79]

11 minutes ago, knocker said:

I would think that a fair call. Regarding the EPS means this morning predictable thay do not follow the det. run with the extensive ridging and the movement north of the upper low to the SSE. Thus the high pressure centre remains to the south west and the cold easterlies are further south over central and eastern France. This portends a transition to a more W/SW regime over the UK as has been indicated by the anomalies

I truly believe that ,as with the GFS ,your default setting is Zonal

[Summer Sun]

 

[knocker]

8 minutes ago, booferking said:

Hot of the press.

I wonder if Matt is being a tad disingenuous here vis his EC comment. If we follow the evolution further the EPS mean NH profile at 00z on the 22nd this morning is totally different to the last EC46 update.There is no Scandinavian blocking and in fact we are looking at a trough by the end of the run.

[Rocheydub]

Or else it has a data issue and is completely wrong! 

Im just warning you all, until the Synoptics are within 96/72, this is no done deal.

[johnholmes]

The anomalies I use each suggest blocking as the main signal developing after the outbreak of the cold NW-N flow, so remaining on the cold side but mostly dry is the longer outlook, say 6-14 days on. If the NOAA 8-14 is near the mark then, currently, eventually this would be replaced by a less cold, possibly, mild and unsettled/changeable 500 mb flow.

links

http://www.cpc.noaa.gov/products/predictions/814day/500mb.php

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

Edited January 10, 2017 by johnholmes
usual spelling errors!

[Met4Cast]

1 minute ago, knocker said:

I wonder if Matt is being a tad disingenuous here vis his EC comment. If we follow the evolution further the EPS mean NH profile at 00z on the 22nd this morning is totally different to the last EC46 update.There is no Scandinavian blocking and in fact we are looking at a trough by the end of the run.

He does go on to ay that there is a significant spread beyond 168hrs so maybe all 51 members are on board with the initial Easterly flow, but beyond that it could still go either way? Doesn't necessarily mean a prolonged Easterly, but certainly encouraging at this range anyway.

[loafer]

1 minute ago, Summer Sun said:

 

Well it will always spread at some point. What the ECM is showing is consistency to T+168, which is a strong signal and further out that we might normally expect.

[frosty ground]

2 minutes ago, knocker said:

I wonder if Matt is being a tad disingenuous here vis his EC comment. If we follow the evolution further the EPS mean NH profile at 00z on the 22nd this morning is totally different to the last EC46 update.There is no Scandinavian blocking and in fact we are looking at a trough by the end of the run.

Just out of interest are you comparing Matts Comments on a chart 7 days from now with a different set of Data 12 days from now?

[snowbob]

5 minutes ago, Johnp said:

But if you read what Knocker has written, how can all 51 members be in agreement?

Only commenting on matts tweet so in answer to your question it's up to 168 not the whole run

[knocker]

3 minutes ago, Daniel Smith said:

He does go on to ay that there is a significant spread beyond 168hrs so maybe all 51 members are on board with the initial Easterly flow, but beyond that it could still go either way? Doesn't necessarily mean a prolonged Easterly, but certainly encouraging at this range anyway.

I doubt it does mean that as the mean at T180 has the riidge over the UK and a light anticyclonic drift from the north

[knocker]

2 minutes ago, snowbob said:

Only commenting on matts tweet so in answer to your question it's up to 168 not the whole run

That is very much the point

[knocker]

6 minutes ago, frosty ground said:

Just out of interest are you comparing Matts Comments on a chart 7 days from now with a different set of Data 12 days from now?

I'm not comparing anything merely suggesting his tweet was maybe a little premature. I'm not disagreeing with what he said as I'm not that presumptions not being privy to the data.

[Rocheydub]

ARPEGE high Res not showing much in the way of snow, or precipitataion on Thursday, when we're supposed to be at our coldest over the coming days! Slightly worrying for the near term. 

Could possibly be a wash/dry out if this were correct. This may come down to radar watching and nowcasting!

[Summer Sun]

If GFS is correct vast parts of central and eastern Europe see mean surface temps remain below zero for the foreseeable future the UK's temps remain around average or a touch below

Should an easterly break out like ECM shows this would change

[Met4Cast]

NetWX-SR is showing shower acitivty across Northern and Western parts as early as Wednesday evening, turning increasingly to snow as the evening progresses.

NetWx-MR, slightly lower res goes out past Thursday, it has the precip on Thursday moving through South-Western parts showing mostly as rain and then moves back out into the channel, doesn't get into Central Southern parts at all.

 

[SLEETY]

Until I see an easterly being modeled at + 72 hours,I'm not getting excited,how many failed easterlies have there been the last decade or longer,fingers crossed ,but long way to go yet.

[Sky Full]

ECM and GFS look broadly similar at +168hrs....

  

After that, the CFS suggests that the cold conditions to be sustained for more than a week at least....

   

I know how little reliance can be placed on these images but it does show what could happen and we are in the coldest phase of winter so I think they are worth posting?  I am intrigued to see that cold pool in mid-Europe being drawn right over the top of us.....  The next few days will be very interesting as this could be the start of a very memorable winter spell during which almost all of the U.K might see some notable snow.

[Weathizard]

What is the point of mean surface temperature charts? It might be helpful if you live somewhere that hasn't got a volatile weather pattern but somewhere like the UK you could have 65% Easterly and 35% westerly and it just leaves you with an 'average' prediction.

 

Edited January 10, 2017 by Weathizard