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

[The Northern Ramper]

Yes its a similar pattern to what we had in January and last week and the GFS doesn't seem to bode well in these kind of situations.

If the Ukmo and ECM building blocks match at 96/120 then I know where my money is.

[snowangel32]

Yh i agree the gfs models have not been gd all through winter and i am not just saying that because its not showing cold its a clear observation that it is badly struggling at the moment and needs to be looked at. Is it an american model is that why it always prefers to bring in the atlantic

[The Eagle]

GFS has been awful this winter. Don't see why I would trust it now. And no i'm not just saying that because it does not show cold. It has been very disappointing.

Here is something that might get people's hopes up

00z ECM ensemble mean 168

12z UKMO 144

[Methuselah]

UKMO 144

WOWWWWW

http://www.meteociel...44-21.GIF?13-17

remember this mornings comments...... The shortwave comes west..

S

Now let's see if it actually does?

[fergieweather]

Interesting dichotomy developing for UKMO, given MOGREP's (thus-far rejected) firm signal for a more unsettled SW regime to develop with milder conditions into the 15 d period (after anticyclonic S/SW)... as of this morning they discounted this and the NCEP version of events and steered slightly more to EC's broadly colder anticyclonic story (purely because of consistency in recent runs) then giving-way to the SW regime after 15 days or so, but it'll be mighty interesting to see how this balance of opinion might sway depending on 12z output from EC and later MOGREPS.

[SMU]

once again then the MOGREPS suite a fair mile away from the ECM & UKMO OPs-

Havent seen any post from Ian all winter that suggests they are any good- always following rather than leading-

S

[Man With Beard]

Interesting dichotomy developing for UKMO, given MOGREP's (thus-far rejected) firm signal for a more unsettled SW regime to develop with milder conditions into the 15 d period (after anticyclonic S/SW)... as of this morning they discounted this and the NCEP version of events and steered slightly more to EC's broadly colder anticyclonic story (purely because of consistency in recent runs) then giving-way to the SW regime after 15 days or so, but it'll be mighty interesting to see how this balance of opinion might sway depending on 12z output from EC and later MOGREPS.

Thanks for that Ian, tbh if you saw today's T0-T48 in isolation you'd be thinking SW'lies for the following period would be a good bet but something strange has been happening since early Jan, northern blocking seems determined to reassert itself over and over. Another shot at cold must be the favourite now that UKMO and ECM seem to singing the same story at T144

Edited February 13, 2013 by rjbw

[chris55]

UKMO certainly is a peach tonight, and picking up from the theme that the EC was first to spot, and which both models have been toying with over the last few runs. Good consistency and a great synoptic evolution.

[johnholmes]

once again then the MOGREPS suite a fair mile away from the ECM & UKMO OPs-

Havent seen any post from Ian all winter that suggests they are any good- always following rather than leading-

S

a biased post Steve if I may say so unless of course you can actually see the MOGREPS output.

[johnholmes]

Interesting dichotomy developing for UKMO, given MOGREP's (thus-far rejected) firm signal for a more unsettled SW regime to develop with milder conditions into the 15 d period (after anticyclonic S/SW)... as of this morning they discounted this and the NCEP version of events and steered slightly more to EC's broadly colder anticyclonic story (purely because of consistency in recent runs) then giving-way to the SW regime after 15 days or so, but it'll be mighty interesting to see how this balance of opinion might sway depending on 12z output from EC and later MOGREPS.

Very interesting post that Ian. I suspect it is not that often, unless SM is correct in his comment, that the senior man ditches MOGREPS I would think?

Interesting that beyond 15 days he is swayed to follow the SW regime. Looking at the 500mb charts, my only view of what the upper pattern might be that I trust, none of them over the past 24 hours with GFS included and 72 hours if one discounts its version, have suggested anything more than a block somewhere fairly close to the north of the UK?

[fergieweather]

a biased post Steve if I may say so unless of course you can actually see the MOGREPS output.

Correct. And the DECIDER suite. Note I stressed Exeter currently reject the MOGREPS solution - that doesn't mean it's ultimately going to be incorrect at 15 days range. It's a judgement call.

Incidentally - the MOGREPS-G and R solutions have been very good recently with snow events. Much better than NAE, often.

[PB22]

Looking through the GFS 12z ensembles at T+144, only a couple lean towards the UKMO 12z thinking, the pick probably being perturbation 18:

http://modeles.meteo...18-1-144.png?12

The rest are mainly under a anti-cyclonic south/south-westerly flow.

For what its worth, the GEM 12z at T+144 is more like GFS operational:

Edited February 13, 2013 by Paul B

[Cheshire Freeze]

Correct. And the DECIDER suite. Note I stressed Exeter currently reject the MOGREPS solution - that doesn't mean it's ultimately going to be incorrect at 15 days range. It's a judgement call.

Incidentally - the MOGREPS-G and R solutions have been very good recently with snow events. Much better than NAE, often.

NAE has been awful IMO.

Though RE MOGREPS, I picked upon one of your posts last week which stated MOGREPS was going for SW cyclonic flow later this week, over the weekend and beyond. I said I couldn't see it then and I still can't. Looks like it could have been somewhat off, for the nearer timeframe at least.

As ever we'll have to wait and see what transpires

Looking through the GFS 12z ensembles at T+144, only a couple lean towards the UKMO 12z thinking, the pick probably being perturbation 18:

http://modeles.meteo...18-1-144.png?12

The rest are mainly under a anti-cyclonic south/south-westerly flow.

Same as the 6z suite then

[weather eater]

Excellent UKMO and as far as easterly’s go I have more faith in it than the GFS or the ECM, the GFS is certainly floundering but it’s not as I stated earlier just a simple case of the GFS is wrong so therefore the ECM or UKMO is correct, it’s still a long way to go to get a decent cold and snow shot to the UK and a lot of time for model outputs to evolve off in a different direction.

Edited February 13, 2013 by weather eater

[fergieweather]

Very interesting post that Ian. I suspect it is not that often, unless SM is correct in his comment, that the senior man ditches MOGREPS I would think?

Interesting that beyond 15 days he is swayed to follow the SW regime. Looking at the 500mb charts, my only view of what the upper pattern might be that I trust, none of them over the past 24 hours with GFS included and 72 hours if one discounts its version, have suggested anything more than a block somewhere fairly close to the north of the UK?

Just chatted through the MR story with them. Essentially they think MOGREPS reverting to a zonal default and thus rejected. On other hand, they stress that at that range, no certainty whatsover on solution re scope of blocking and so they're not fretting over it. They've little interest in speculation beyond end of next week.

[Froze were the Days]

A quicker evolution than ecm as well, not sure what the uppers would be from the ukmo now the sun strengthens. Last chance saloon for gfs for any credibility this winter coming up but you wouldn't bet against the other two at present,

[Cheshire Freeze]

A quicker evolution than ecm as well, not sure what the uppers would be from the ukmo now the sun strengthens. Last chance saloon for gfs for any credibility this winter coming up but you wouldn't bet against the other two at present,

Did Ian Brown oversee the last GFS 'upgrade'

(P.s Ian knows I'm only joking)

Edited February 13, 2013 by CreweCold

[PB22]

Excellent UKMO and as far as easterly’s go I have more faith in it than the GFS or the ECM, the GFS is certainly floundering but it’s not as I stated earlier just a simple case of the GFS is wrong so therefore the ECM or UKMO is correct, it’s still a long way to go to get a decent cold and snow shot to the UK and a lot of time for model outputs evolve to off in a different direction.

I remember a couple of years back that having the UKMO model on board for an easterly was a necessity...numerous times I can remember the GFS going for easterlies in the 5-7 day range but the UKMO didn't and on most, if not every, occasions the UKMO was nearer the mark. I'm not sure how the models have progressed since then, but I'd still feel happier seeing the UKMO showing an easterly rather than the GFS. Nonetheless it will be fascinating to see how this period pans out.

[fergieweather]

On the T+144 GM, Exeter also point-out it's nothing surprising - holds with their previous story issued earlier today of "....also a risk of wintry showers affecting some E/SE’ern parts at times. Conditions may also turn quite breezy at times in the NW, E and S. Tending to turn colder, especially over E/S/Central parts...".

Anyway, miles off in time-frame and reliability, so can understand why they're not paying it much focus at present.

[Frosty.]

a biased post Steve if I may say so unless of course you can actually see the MOGREPS output.

I don't think MOGREPS has supported cold weather all winter, all I seem to read on here is how mogreps is against any other model showing a cold outlook, the ecm for example, if the ecm shows cold, mogreps says mild blah de blah, anyway, ukmo 12z is peachy for cold potential and hoping for another very cold and blocked ecm but with more snow potential this time please.

[Captain Shortwave]

Whilst there is little between GFS and UKMO at T72, the orientation of the low in the atlantic differs quite a bit

UKMO is aligned to allow WAA to move straight northwards, this allows the split of the shortwave to our north away from the main Atlantic trough, giving faster height rises north.

GFS on the other hand has a much messier atlantic trough which alligns the WAA more North Easterly in direction, this means the shortwave doesn't split cleanly and allows heights to build unfavourably over us.

It's a small difference but has a massive effect on the rest of the output.

[SMU]

Hi John- How can I be biased if I cannot see a model>?

All winter long I have logged Ians snippets- when something cold is around the corner from the ECM OP & the UKMO OP then from what I have read that particular suite then comes on baord a day or 2 later-

It may be better at short term synoptics than medium term ones....

Im sure if the trend of UKMO + ECM op continues over the next 24/48 hours then the colleagues @ Exeter will soon start to focus on next week- as it stands though im sure most will happy to get a warmer weekend out of the way ( away from the far SE corner)

regards

S

[That ECM]

On the T+144 GM, Exeter also point-out it's nothing surprising - holds with their previous story issued earlier today of "....also a risk of wintry showers affecting some E/SE’ern parts at times. Conditions may also turn quite breezy at times in the NW, E and S. Tending to turn colder, especially over E/S/Central parts...".

Anyway, miles off in time-frame and reliability, so can understand why they're not paying it much focus at present.

And who could blame them. It has been hard enough to forecast for upto t72. Might add that over the short term they have done very well for much of the winter.

Like most on here though we are looking seven days plus for that beast. Certainly not having ago at sm, I have learnt so much especially with regards to the model bias. The ones we can see anyway!!

[fergieweather]

And who could blame them. It has been hard enough to forecast for upto t72. Might add that over the short term they have done very well for much of the winter.

Like most on here though we are looking seven days plus for that beast. Certainly not having ago at sm, I have learnt so much especially with regards to the model bias. The ones we can see anyway!!

Yeah, I think the other key point here (MO at pains to stress this) is you can't compare EC/GFS or other similar GM models with MOGREPS. They're very different animals. Ditto DECIDER. Anyway - let's see what 12z EC makes of it all. Cheers for now.

[Buzzit]

Just chatted through the MR story with them. Essentially they think MOGREPS reverting to a zonal default and thus rejected. On other hand, they stress that at that range, no certainty whatsover on solution re scope of blocking and so they're not fretting over it. They've little interest in speculation beyond end of next week.

Thanks for that Ian, it brought back to the forefront of my mind, the concept that we are still many moons away from being able to accurately forecast to any extended length of time. Personally, I think we are at the point where we could do with a lot more investment by the EU in measuring devices for the Arctic / Subarctic regions - just my two cents, but I believe this is the biggest barrier to improvement in model output at the present time. The USA can afford to send Hurricane Hunters every few hours, so why we cannot afford to fly a couple of planes around every day is far beyond my comprehension.