Winter Model Discussion 18Z 12/2/13 onwards.

[Frosty.]

the GFS may not be as good but if you look at some of it's previous runs in the last 24 hours we do see it slowly improving one thing that has changed is the GFS yesterday was showing a big deep Atlantic low not many on here were convinced that it was right on it and today the GFS has dumped the idea of the very deep low and made it a whole lot weaker this is a good early sign. .

Firstly, the Gfs 12z is light years worse than the ukmo and especially the stellar ecm 12z, it has made slight improvements from the 00z with the 12z latching on to the ecm pattern into early next week, but then the gfs 12z is not worth discussing beyond that point.

[LomondSnowstorm]

How many times has a 8 day cold & snowy chart come to fruition without any hiccups or without it being toned down even when like you say the big two are singing from the same sheet..

I don't think anyone is disputing that the ECM will not verify exactly as shown, whether or not it gets upgraded, downgraded or just moved around a bit, but broadly speaking at this kind of range it's the broader pattern we should be looking at. In this respect, the ECM and UKMO (along with the earlier ECM ensembles at least) are very similar at +144 with the GFS once again looking rather different (though less so than 24 hours ago). Given we've seen similar patterns resolve towards the ECM/UKMO solution and we understand that the GFS does have certain biases broadly speaking the ECM/UKMO solution of heights to our north should be favoured over the GFS solution, for the moment. Embellishments are always likely to change but if that broader pattern does indeed verify a decent easterly would at the very least be in play.

[mcweather]

Normally I would like to see all three models on board in advance of a possible cold/very cold/ snowy spell. However the GFS operational has performed so abysmally in advance of cold spells this winter that I,m really not that fussed and if you can only have two of the top three onside then having the top two verifying models of the top three is good enough for me. GFS will eventually be dragged kicking and screaming to the table at which point we can spend a happy few hours force feeding it a big plateful of humblepie.

[The Eagle]

ECM ensembles show marked uncertainty and deviation. Some similar members to the op though.

[DEYS(Kent)]

Synoptically I'd say the ECM ENS generally support the Det Op.

[SMU]

http://www.knmi.nl/exp/pluim/Data/PLUIM_06260_NWT.png

Fantastic ensembles for debilt- almost 90% agreement on surface temp-

Where things differ will be the uppers & the angle of attack being south east or east...

S

[Paul]

Any chance we can discuss the models in here please - there's a whole thread elsewhere dedicated to lrf's if anyone wants to talk about them..

[chris55]

De Blit 10 day ens, good support for the Op.

[mcweather]

ECM ensembles show marked uncertainty and deviation. Some similar members to the op though.

I,m sorry eagle they do nothing of the sort. They show a major clustering towards the coldest option.

[Frosty.]

looking forward to more good news from De Bilt ensembles EPIC T+240 chart

Just read steve's post, excellent news from De Bilt

[DEYS(Kent)]

Those charts only make The Eagles comment about the ECM all the more ambiguous. Cracking set I'd say.

[kent]

UKMO and ECM very good charts for coldies. As per usual GFS doesnt want to join the club. At present you could expect the usual watered down outcome of the former two,but it will all probably change again by tomorrow if its consistancy youre after.

[chionomaniac]

http://www.knmi.nl/e...M_06260_NWT.png

Fantastic ensembles for debilt- almost 90% agreement on surface temp-

Where things differ will be the uppers & the angle of attack being south east or east...

S

With a pretty good H500 mean at T+192 as well.

[That ECM]

I was commenting on the ECM run only. Contrary to what the likes of chino thinks. I am as big as a snow and cold ramper as the next. However unlike some on here i fail to get happy over charts that are out in fi ( Especially after the winter we have had thus far ).

- If we look at the past two cold spells that has happened these are the steps it has took.

1 - Great fi runs & the forum goes into meltdown.

2 - As we get closer & closer it gets watered down.

3 - Right down to it now & we are facing a brief colder snap with marginal temps & dp's.

So whats my point?

= I dont buy it ( Especially the way this winter has panned out ) until reliable no matter if every single model showed consistency.

Very wise not to get to excited about charts that are in fi. Also not wise to view current output with past experiences/ let downs affecting your judgement. Two references in your post talking about how this winter has panned out. This can effect objectivity.

Finally, I see that RP edited your initial post and I hazard a guess you were upset by quip. Apologise if this was the case, no offence was meant and the written word is always open to miss interpretation.

[Summer Sun]

ECM full ensemble

Still a fair few milder members long term

[SMU]

Without getting to far ahead & the usual disclaimers - theres a strong tinge of Feb 2009 in here tonight

http://modeles.meteociel.fr/modeles/reana/2009/archivesnh-2009-2-1-0-0.png

Also-

http://modeles.meteociel.fr/modeles/reana/2009/archivesnh-2009-2-3-12-0.png Wasnt this the chart that brought 40cm of snow & slurrey to a standstill>?

Lets hope the allignment is good again....

S

[Timmytour]

I think it's easy to disregard the ECM on the basis that we've seen the Easterly before with the promise of freezing temperatures, only for it to fail in the delivery in the extent of what it modelled. But what catches my eye this time is the cold pool that it's pouring into Europe this time, more impressive than on the last two occasions imo.

As always i will wait for the GFS to get on board....but I think this time I see enough about the ECM's evolution to believe that it will and pretty quickly.

Just the one note of caution.....i think the extent of cold to the east matchres what was there to tap into potentially in Decemeber. So nothing can be said to be nailed until the hammer hits and the surface gives way!

[shotski]

The 500mb Anomoly charts would seem to back up ECM & UKMO evolutions.

Large anomoly to the north of the UK.

[Methuselah]

IMO, there's no getting away from the fact: if the ECM verifies, we'll all remember the outcome... Maybe something similar to what happened in the middle of February 1979?

[mcweather]

Without getting to far ahead & the usual disclaimers - theres a strong tinge of Feb 2009 in here tonight

http://modeles.meteo...009-2-1-0-0.png

Also-

http://modeles.meteo...09-2-3-12-0.png Wasnt this the chart that brought 40cm of snow & slurrey to a standstill>?

Lets hope the allignment is good again....

S

Bit of a whiff of Feb 1978 as well Steve

[london-snow]

Very wise not to get to excited about charts that are in fi. Also not wise to view current output with past experiences/ let downs affecting your judgement. Two references in your post talking about how this winter has panned out. This can effect objectivity.

Finally, I see that RP edited your initial post and I hazard a guess you were upset by quip. Apologise if this was the case, no offence was meant and the written word is always open to miss interpretation.

Maybe i am having a off day so apology accepted.

Yes i do go on past experiences and am thinking back to the previous snaps we have seen of late.

But i also base it around the history & that history is that we very rarely see day eight charts come to fruition that is the only point i really have to make here. I have been hurt in the past by chasing the cold jackpot & i am refusing to get drawn in until reliable because of past fails.

I hope reverse psychology works for me as everyone who knows me on here knows that i love deep cold and plenty of snow. I'm just going to hang tight on the fence for a bit.

[TootyFruity]

Hi the charts look great and may I just say Steve M is a legend ... But what are the chances of the ECM charts downgrading andvthe GFS charts upgrading as they have done in the past to meet somewhere in the middle ? And it be a non event again ... ECM loves the easterlys and who can blame it I love a stiff easterly but it does tend to big itself up a tad to then over a few days come online with the GFS .

Please be nice this is very scary x

[Snowman.]

ECM full ensemble

Still a fair few milder members long term

To be fair the Mid term catches my eye.

[london-snow]

Without getting to far ahead & the usual disclaimers - theres a strong tinge of Feb 2009 in here tonight

http://modeles.meteo...009-2-1-0-0.png

Also-

http://modeles.meteo...09-2-3-12-0.png Wasnt this the chart that brought 40cm of snow & slurrey to a standstill>?

Lets hope the allignment is good again....

S

It was & if i remember i got near a foot of it and you was contemplating a drive to my town after viewing the ppn rates in the regional thread.

I hope not though steve even though 40cms would be nice. It went the next day or so following it melted dramatically thanks to milder muck.

Give me 5cms with it sticking around & i am happy as a pig in muck.

+

Edited February 13, 2013 by london-snow

[damianslaw]

As we've bceome accustomed too in recent weeks, GFS showing a very different outlook to the ECM/UKMO. I said yesterday the GFS struggles when it comes to 'blocked patterns' especially when the blocks are of european origin.

The jet is forecast to dig southwards next week - I therefore can't see much energy going NE into the Norweigen Sea as suggested by GFS.

The broader picture is for a 'blocked' outlook with a weak ineffective atlantic.

A very amplified atlantic trough is forecast to develop early next week sending warm air advection up towards west greenland which enables heights to our east to build rapidly and crucially to our NE, whilst at the same time kicking the azores high far to the SW, the trough will then be either forced to disrupt or more likely send shortwaves SE towards Spain and central europe. The key trigger will be the movement of the PV lobe out of Canada and towards Siberia as suggested by ECM this would open the floodgates to a significant arctic pool of air from the NE as heights retrogress to Greenland.

The UKMO 144hr output suggests such a transition to bitter cold could easily come from the north rather than the east with heights building out of the arctic.

I'm barely bothering with the GFS at the moment..