Winter Model Discussion 12Z 09/01/13> The hunt for cold ?

[snowblizzard]

To be honest the best thing to do now is watch to bbc forecasts in the coming days. Most people on this forum always wait for their confirmation of cold weather, weather warnings etc so I believe this is the way to know the longevity of the cold snap without wasting too much of your life on line

Last night, the BBC Weather Presenters were definitely getting more exited about v cold & possibilities of snow next week. This morning, they seem to be supressing it again!

Still no model agreement though!

Edited January 10, 2013 by snowblizzard

[NorthernRab]

Trust me. That would not be a snowy outlook, apart from higher ground. I expect it will look different later today though.

For much of the UK that would bring considerable snow, low-lying areas included.

[Gustywind]

Sorry but the ECM has definitely taken a step towards the GFS in the short range this morning, the initial movement of the shortwave is now east not south east, which means less cold for the uk. Yes it does then take it south east as before but that is past t96 so is FI at present. It's the initial eastwards motion that is telling and that is as per GFS. Writing on the wall now I fear for this cold spell, but still time fir things to change, desperately need a slightly stronger more northerly Scandi high to prevent that eastwards movement, still time for this to change.

Huge coup for GFS though having stood alone last night and been rubbished by all and sundry.

[Ian Brown]

Well the GFS remains rock solid with it's OP run and whilst there is still a sharp ensemble split, more runs now go with a quick Atlantic return next week, with a strongly zonal route going forward.

The ECM is beginning to wobble with heights weakening to the North but still enough to deflect Atlantic systems on a Southerly track. It's a well worn downgrade path from past years - the models start to show easterlies, then it becomes South Easterlies as the Atlantic charge is picked up, then it becomes...well what the GFS shows.

Hard to believe that there can be such uncertainty in 2013 at such a short range, but I think we must now back the GFS as having pulled off a big coup and I would think the ECM ensembles will reflect many members like the GFS and the OP will look much like it tonight. Will be interested to see how the METO react later today.

[IDO]

Well that was torturous viewing. This forum, not the models.Some frankly ridiculous posts this morning.

ECM OK, a bit meh after yesterday's 00z but like I mentioned at the time it seemed all a bit too soon to me.It's heading the right way through the run and unlike the GFS, which is again completely out of kilter, it looks fine to me going forward.

UKMO good but it is lo res after +72 and often tends to' under complicate' things.

Another set of runs, another set of possibilities, all stil look very good to me.

The ECM is OK at the moment but it is a U-Turn. From an easterly (both runs yesterday, from next Tuesday) to a cool/cold westerly flow. That is a big synoptic change. May still get cold/cool/snow but thats not the point. It only has to shift north a few hundred miles and it would mirror the GFS.

[Ian Brown]

Of course they have shifted.. 72 - 96hr on the ECM has the Low going West to east across Iceland, 96hr to 120 and it barely sinks. Yesterday it dropped quickly SE. So the game is changed from an Easterly to a Northwesterly and a pattern that looks weaker and on a knife edge as they say. If the ECM output corrects again and keeps that Low to north (which looks even more plausible today) then it will go pear shaped. What happens after 96hr doesn't really matter atm.

The GFS refuses to eject it SE yes but this morning the ECM is showing a lot of reluctance in doing that also.

Yes that's the huge shift in the ECM this morning, after that both models pick up on a rampant Atlantic signal, it's just that because the ECM handles it slighly differently pressure rises enough to the NW to deflect the angle of attack.

[Penicuikblizzard]

As I keep saying and most ignore this, but fact!! GFS picked this same trend up back in December all the models were going Easterly and GFS changed to Zonal and proved to be correct, the only crumb of comfort for coldies this time is the SSW, but nothing is certain!!

[Gustywind]

I agree with Ian however what I would say is this is still on a knife edge andcitvwould take very little for the GFS to move back towards the UKMO and vice versa, still no solution this morning however past experience suggests mild is likely to win out.

Another thing slightly worrying me from a cold perspective is I don't recall in over 5 years if model watching seeing a solution like the UKMO/ 12z ECM ever verify for the uk, I.e low pressures forming in the GIN corridor then diving sharply sse, they almost always move east or north/north east. Not saying it can't happen but I've never seen it before so is clearly highly unusual and hence in itself unlikely to verify that way. Still here's hoping I'm wrong.

[NorthernRab]

As I keep saying and most ignore this, but fact!! GFS picked this same trend up back in December all the models were going Easterly and GFS changed to Zonal and proved to be correct, the only crumb of comfort for coldies this time is the SSW, but nothing is certain!!

The reason most ignore it is because it doesn't really have anything to do with the current lack of clarity.

[snowangel32]

Yep have to agree although still time for change the ecm model has clearly back tracked towards the gfs model, and i am new to all this, and even i could see the short wave takes a different track i fear greatly for ecm on the next model run so hope the gfs dosent win though

[Paul]

As I keep saying and most ignore this, but fact!! GFS picked this same trend up back in December all the models were going Easterly and GFS changed to Zonal and proved to be correct, the only crumb of comfort for coldies this time is the SSW, but nothing is certain!!

That was December, this is now - no two weather situations are identical, so what happened then is irrelevant. There is a chance the GFS will be correct but that has nothing to do with what happened last month or indeed any time before it.

[iowpompeylee]

Chris Fawkes on twitter!!@_chrisfawkes: ec model has cold arctic air getting dragged across scandinavia, if correct next weekend (10 days away) could be v interesting. One to watch...the professionals.still edging towards a cold period

[R.P. McMurphy]

I have to say, hats off to Ian Brown for sticking by his guns & not over ramping/jumping the gun. We desperately needed the GFS to come on board with the other models to be sure of a full blown blast, something which never happened. We now see the ECM back tracking towards the GFS bringing in the Atlantic towards the middle of next week. It's a shame as the synoptics were fantastic, but tough ol' GFS wasn't budging, and fair play to that model. I understand Paul says there are no two weather events / setups exactly the same which is true indeed, but the GFS has been in outstanding form when all other models have been showing different setups. Will wait for updated ensembles / models which again, might just swing back for the better, but i'm not holding my breath.

[Long haul to mild]

Here we go again, posts congratulating a model on getting it right when we are still a long way away from any agreement or consensus.

It can be a totally maddening experience on here to be honest and this morning is a low point.

[bluearmy]

remember that ukmo runs at very high resolution out to T72. there is clearly a data isssue between ncep and the other modelling re the scandi blocking. whether ncep is right will become apparent later today. as far as the longer term is concerned, the ecm ens will reveal whether the greeny blocking is subsiding as per noaa cpc's caveats last evening.

its never straightforward for us.

exeter have a big call re monday. a hundred miles either way on entry from the north makes a massive difference for the uk

[Gustywind]

Think I said earlier this week that all models but in particular the ECM and UKMO have performed abysmally this winter whenever a potential cold spell has reared it's head. The GFS hasn't been great either but has generally found the correct solution first and the others have followed kicking and screaming. The GFS seems a bit more dynamic in these types of situations.

[Jason H]

Thats not Matt Hugo.

[thesnowman]

Well the GFS remains rock solid with it's OP run and whilst there is still a sharp ensemble split, more runs now go with a quick Atlantic return next week, with a strongly zonal route going forward.

The ECM is beginning to wobble with heights weakening to the North but still enough to deflect Atlantic systems on a Southerly track. It's a well worn downgrade path from past years - the models start to show easterlies, then it becomes South Easterlies as the Atlantic charge is picked up, then it becomes...well what the GFS shows.

Hard to believe that there can be such uncertainty in 2013 at such a short range, but I think we must now back the GFS as having pulled off a big coup and I would think the ECM ensembles will reflect many members like the GFS and the OP will look much like it tonight. Will be interested to see how the METO react later today.

excellent post - Zonal is now ROCK SOLID from the GFS - just look at charts past Monday.. ECM falling behind the GFS now - as expected

[iowpompeylee]

Matt Hugo's twitter....@MattHugo81: 00z GFS still not having it and to an extent ECM not just as impressive. Until the GFS 'comes on board' there is always some uncertainty.

[lord stratus]

I agree with Ian however what I would say is this is still on a knife edge andcitvwould take very little for the GFS to move back towards the UKMO and vice versa, still no solution this morning however past experience suggests mild is likely to win out.

Another thing slightly worrying me from a cold perspective is I don't recall in over 5 years if model watching seeing a solution like the UKMO/ 12z ECM ever verify for the uk, I.e low pressures forming in the GIN corridor then diving sharply sse, they almost always move east or north/north east. Not saying it can't happen but I've never seen it before so is clearly highly unusual and hence in itself unlikely to verify that way. Still here's hoping I'm wrong.

What's the betting, the GFS will show raging easterlies in FI on the 12z or 18z.

[Severe Siberian icy blast]

Another morning, another lot of very poor commentary in here.

NEITHER have shifted. They are both variations on their own theme. ECM less cold than yesterday's runs but still has the shortwave slide SE over the UK, and still has a lot of snow potential into next week, and had NOT shifted towards GFS. If it had shifted towards GFS we would not be having the Greenland height rises.

The GFS still refuses to eject it SE, so we wait for another set of runs!

UKMO different from its 12z output - still cold but yet another variation!

SK

Finally a more accurate post .

The ECM is basicly the same as the last one , when looking for trends past 120z you should never look at 850's as a guide as they will always change , the theme is this .

ECM - trend for undercutting lows and high pressure to build over greenland. (Also massive snow potential next week)

UKMO - trend for undercutting lows and high pressure to build over greenland. (Also massive snow potential next week)

The gfs on its Own , the ECM was always going to downgrade the uppers at some point , but we have a very snowy picture next week , and I for one can't wait.

[john pike]

too much scatter on these 15th-16th to start congatulating gfs yet

anyone notice the kontrol run today

http://www.meteociel.fr/modeles/gefs_cartes.php?ech=192&code=0&mode=0&carte=0

http://www.meteociel.fr/modeles/gefs_cartes.php?ech=192&code=0&mode=1&carte=0

thought not

[nick sussex]

You really couldn't make it up.

No agreement within such a short timeframe, I don't think I've seen anything like this in the past.

One look at the UKMO fax chart at T84hrs shows the disparity between models. Off to see what I can find out about the pattern in the USA.

[snow drift]

Why do people feel the need to position themselves in one camp or the other? When forecasting or reviewing the output, it is OK to say, to much uncertanty to have a clear view at this time. If the professionals do it then why can't some amatures.

[SLEETY]

As I keep saying and most ignore this, but fact!! GFS picked this same trend up back in December all the models were going Easterly and GFS changed to Zonal and proved to be correct, the only crumb of comfort for coldies this time is the SSW, but nothing is certain!!

but it isn't correct yet,it was one of the warmest runs in its ensemble pack,not just uk but europe as well