Winter Model Discussion - Cold Hunting -12Z 03/01/13

[Dexter29]

Well until all the models jump on board I'll take it all with a pinch of salt. Normally where the ECM leads persistently the GFS and the rest eventually follow.

Not always - the ECM persistently kept the easterly coming for the DEC 2012 failed cold, while the GFS and UKMO picked up on the zonal and stuck with that and were correct, ECM followed suit thereafter

[UV-RAY]

I'm struggling to see the basis for this statement, and enquire what evidence you have to back it up.

On the verification stats, as I understand it, the ECM is marginally ahead of the GFS (although it's complicated by the GFS having multiple daily runs) but the margins are so tiny, that one can't leap to the conclusion that the GFS is sure to follow the ECM.

Which model picked up that the progged easterly last month was going to fail? The GFS (18z) if I recall correctly, and then the ECM and eventually the UKMO fell into line.

That said, I am not saying that the GFS will win the day. I agree that it is a concern that the ECM is not on board (see Steve's post above) and until it jumps aboard, surely every sensible model watcher should say that predictions of real cold should be treated sceptically.

However, I don't see any basis for predicting the opposite. You could just as well say that the ECM will in time follow the GFS - such a statement needs evidence to back it up.

I'd say Pit was being cautionary until the ECM comes on board, which after the last debacle is the most sensible thing to do.

[Bristawl Si]

I thought it worth re-posting this from Ian F yday evening - not because it's Ian who said it but it's just so so sensible for this period of model torture coming up!

Ian F:

A senior colleague literally just reiterated this key, key point: "No NWP will get a grip until SSW effects feed lower-down into model synthesis." Ignore -in effective sense of preventing any coronary - all GFS output post around mid-late next week. UKMO model equally showing considerable inter-run flux at longer reaches too (it goes to T+168 internally) and all of this is expected / symptomatic / characteristic of how they struggle with the complex dynamics of what is still at an incipient phase. Nothing, as yet, is offering anything surprising nor unexpected. So, please: NO MORE posts bemoaning any lack of profound cold showing at longer range of GFS, or EC, or whatever. It is all - stress ALL - considered effectively unreliable. Period.

Sit tight....!

[johnholmes]

The 500mb ECMWF-GFS issue this morning still builds the ridge over/N/NNE of the UK. I am still not 100% convinced but remain at about 80% that a cold block type of set up is being put into place.

How all the links fit or not I will try and show during today with the Friday upper air update.

I was going to issue this during the next half hour or so but I am having trouble accessing the NOAA AO, NAO and MJO data so it will have to wait until later in the day.

[Weather Boy]

I'd say Pit was being cautionary until the ECM comes on board, which after the last debacle is the most sensible thing to do.

Well, that's not what he said. If he had, I would agree with him. He said that the GFS will in time follow the ECM but I see no evidence at all to back up that statement, hence my request for such back up.

[Tim Bland]

shame the cfs can't be trusted. Lovely run though.

http://www.meteociel.fr/modeles/cfse_cartes.php?ech=174&mode=0&carte=1&run=10

Indeed! CFS is a perfect example of how this could upgrade short term so we could see a nice block / ridge pre 200hrs. Shame it's from Cfs though

http://www.meteociel.fr/modeles/cfse_cartes.php?ech=198&code=0&carte=1&mode=0&run=10

[Summer Sun]

Anyone see the BBC 1 forecast after the 10 O`clock news some big hints from John Hammond about changes mid month what this space he said

Anyway back to the models and brrrrrrrrrr

Edited January 4, 2013 by Gavin.

[UV-RAY]

Well, that's not what he said. If he had, I would agree with him. He said that the GFS will in time follow the ECM but I see no evidence at all to back up that statement, hence my request for such back up.

I see your point, I think in general that is the case but as this winter has shown there are exceptions.

[Tim Bland]

The GFS is the most extreme Northerly solution with the ridge, the ECM is the most flat- UKMO in the middle- but a big move from yesterday-

We need the most extreme solution to varify if we want that cold shot from the east- anything flatter & the train will be stopping in Europe..

S

IMO in these situations we often end up with a middle ground between the models so its possible that the cold on this occasion will grind to a halt to our east. However we have more than one bite at this cherry and if cold is established to our east it will be more tasty if it arrives!

[That ECM]

The plot thickens. With some real eye candy on offer. I would like to see the ECM trend more towards the GFS. Knowing the models, ECM will show good heights building to the north and GFS will drop the idea on the next run.

I do like the move forward by UKMO this morning and the fact it only goes to t144 maybe the limit of time we should look at in detail until we get to see how the SSW plays out.

Regards.

That ECM

[nick sussex]

Quite surprised this morning to see the GFS holding out against the flatter ECM/UKMO.

It has had several runs now to move towards them but still won't budge. The UKMO is a slight improvement on last night but even with that couldn't develop like the GFS and the ECM becomes flatter this morning.

Looking at the MJO forecasts perhaps the model that calls that correctly will have the pattern near the UK more accurately modelled.

[weather eater]

ECM vs the GFS, I very much doubt either is right, ECM better overall, GFS arguably better with blocked patterns it certainly outperformed the ECM in 2010 by a country mile. However as has been said the models are going to struggle with the Stratospheric changes and we are going to plenty more solutions over the coming days, some good some bad. Personally I'd rather not see Stella runs in FI they always end up a letdown.

[Paul_1978]

Think too many are expecting this ssw event to bring cold to the uk to be garenteed. Sorry but dont think it will happen like that. Never thought i would say it but im with brain gaze on this one. With the uk missing out on the cold. Think the models will firm up late weekened early next week. But not expecting anything cold and snowy to hit the uk im afraid. The esembles dont look too good for us. The azores high looks like remaining dominante keeping us on the mild side. All im saying is dont get your hopes up again. As you may be very dissapointed again.

Cheers for that insight.

[Summer Sun]

For those who missed what John Hammond had to say about mid month last night the forecast is available here jump to 2:15 if you want to skip the rest of it http://www.bbc.co.uk/iplayer/episode/b01ph60q/BBC_Weather_03_01_2013/

[Weathizard]

Normally hard to observe differences at 108+ but this run so far looks further east and flatter.

[ghrud]

For those who missed what John Hammond had to say about mid month last night the forecast is available here jump to 2:15 if you want to skip the rest of it http://www.bbc.co.uk...her_03_01_2013/

Use the right bate and you’ll catch a lot of fish (not Michael). I still think too much hope is being pinned on the SSW event. Raise your expectations too high and it will hurt even more when we miss out… yet again!

[TEITS]

I still think too much hope is being pinned on the SSW event. Raise your expectations too high and it will hurt even more when we miss out… yet again!

If it wasn't for the SSW we wouldn't be discussiing the potential and looking at some of the eye candy runs. Whilst this doesn't mean cold for the UK the effects of the SSW are clearly being shown on the NWP.

[thesnowman]

1. Why are people guessing at the result of the SSW when no one knows the result for us? - NOT EVEN THE MET OFFICE EXPERTS KNOW!!
   
2. Why do we need to be told that it won't be good for us, When no one Knows? - AGREE
   
3. Why is the GFS wrong and ECM right, when no one knows? - WHEN PEOPLE LIKE HOW IT LOOKS
   
4. To (TOO) many people want to make a judgement in the hope that they can say told you so. -THIS SITE IS FULL OF KNOW IT ALLS - only a few are sensible TEITS as an example
   
5. There is more chance of cold now than there has been due to various indicators, so lets see how it pans out. I think everyone knows we may miss out but..... - THIS HAPPENS AS WE APPROACH MID WINTER
   
6. Lets see where we go from here and learn as we go. - WHAT WILL BE WILL BE
   

at last.. a nice locally and unbiased view

[Nick F]

The evolution of the 00z GFS control run was certainly what many are hoping for, though unfortunately a cold outlier. The operational was one of the coldest too.

http://www.meteociel...&carte=0&mode=0

A look at the differences between the ECM and GFS operationals on the 8-10 day H500 comparisons

http://www.meteo.psu...0z/hgtcomp.html

... both build heights north, but GFS differs with the angle of the Atlantic trough - GFS has a more negative tilt with undercutting potential bringing lower heights towards SW Europe, which also allows height rises towards Iceland. While ECM has a positive tilt - which brings higher heights towards SW Europe and a more +ve NAO signature.

Positive signs from the ensembles though for blocking to the N or NE, ECM perhaps lagging behind on picking up this signal, but still a way to go until we find out how the block will position itself and how favourable it will be for cold and wintry conditions for us.

Edited January 4, 2013 by Nick F

[SnowBallz]

Newsflash from matt hugo on twitter

Ecm 32 dayer goes now for greenland block and colder 2nd half of Jan

What's that, the ECM32 performs a volte-face - surely not??

It's as mickey mouse as the CFS guys; really don't understand the faith which is continually put in this false prophet. The thing is, there is no model which can forecast out to such range - but it's the implicit trust of this particular model - yet mockery of its peer, the CFS, which is hilarious.

They are both unreliable, both developmental and neither should be trusted.

[swfc]

I think the trend "hate saying that"is for a drier period of weather then later in the month the chance of high pressure becoming more dominant around or over the uk.It could be anywhere in its location so i guess its wait and see for a week or so.Having not seen a snow flake this winter id take a day of snow showers now however it gets here!

Edited January 4, 2013 by swfc

[swfc]

The oz looks flatter and the low to the west a lot more intense?very volatile outputs still but this run looks pretty rank if somewhat in fi past the 120 hr mark

Edited January 4, 2013 by swfc

[Weathizard]

Still miles apart at 192 but I feel the GFS has moved SLIGHTLY towards the ECM here.

Not looking forward to the fall out if this run brings in SW'lies! (Toys being thrown) and/or it all goes to pot! Have to say as well this is what the big cluster on the 0z pointed too, mid lattitude blocking getting a bit stuck and we are stuck west of the cold arctic air.

Edited January 4, 2013 by Weathizard

[No Balls Like Snow Balls]

Still miles apart at 192 but I feel the GFS has moved SLIGHTLY towards the ECM here.

Not looking forward to the fall out if this run brings in SW'lies! (Toys being thrown)

SW'erlies in FI matters no more than raging E'erlies in FI, Don't you read the posts from the Pros?

[Ian Brown]

Still miles apart at 192 but I feel the GFS has moved SLIGHTLY towards the ECM here.

Not looking forward to the fall out if this run brings in SW'lies! (Toys being thrown)

Yes, though quite a few of the 0z ensemble suite went this way. Disappointing because if the High ends up parked to the East with the jet running over the top, it’s another wait for a possible shot at something else further down the line.