Winter Model Discussion - Cold Hunting 08/01/13 00z Onwards

[Robbie Garrett]

I emailed them regarding this, let's see what they reply...

What I dont understand is the METO update was cold or very cold with snow last night from yesterdays 12z. Yesterdays evenings ECM wasnt what we wanted with regards to cold, and they didn't use that output as part of their update. So what were they using, the GFS? Now they wont even consider the GFS and are going with the ECM.

So it seems ignore any output from the GFS until it matches the ECM

[cold snap]

Sorry but you cant just say ignore the GFS.

Now if we cast are minds back again to Nov 2010 ECM was the last to pick it up.when every model wanted to flood cold air west.

I still dont think this is a done deal.

12z will be crucial i believe.

Edited January 8, 2013 by cold snap

[Met4Cast]

Sorry but you cant just say ignore the GFS.

Now if we cast are minds back again to Nov 2010 ECM was the last to pick it up.when every model wanted to flood cold air west.

I still dont think this is a done deal.

12z will be crucial i believe.

The thing that confuses me is that the ECM Ensembles are not particularly mild, the mean remains below 5c throughout the entire run! The MetO though aren't saying mild WILL win out here, they've stressed a lot of uncertainty within their outputs and indeed from what Ian has posted on here too.

I'm not surprised they've ignored the GFS, it really is the most extreme the UK could probably get

[That ECM]

Well I don't quite know what to say really. Sigh. The gfs has masses of potential and wouldn't it just be lovely if that came off!! I do though however worry and unlike yesterday eve my guy feeling is that of Ian's in respect of the ecm being most probable (typical ) I simply just can't see how the gfs can thrust heights northwards without a low or shortwave pushing through ala ecm!

It is however even more frustrating though because all background signals bar the NAO go more or less with Greenland heights which the ecm goes against. Why this is the case seemingly yet again! The other day the ecm showed two runs of very cold conditions n then rapidly changed back to mild. I bet the same opposite first happen here! If the ecm comes out right I think we will be stuck in this pattern for weeks. Regardless of the SSW.

Doesn't *first*

I think it may be worth another read of his posts. He said that they are leaning that way but EC was prob an outlier. Also he talked of huge uncertainty. A day or so ago, he described this weekend and next week as normal winter with the effects of the SSW to be shown in output in the 8 days or so.

If we look at the ens they are currently showing a cold dip around 13th for a few days and then on average tracking back up to the average. This kind of ties in with their latest forecast. This is where the talk of battle grounds comes into play. If it plays out like that, then the FI for detail will be at t24 due to a few miles here or there will have a big impact. The east would be more favourable in term of being winterey due to the cold air coming from that direction.

What I would like is for heights to be shown NW of us then there is more chance for most to see what most would like. As much as it will be of great interest to see the runs this evening, I am sure it will not give the clarity that most of us crave.

[bluearmy]

Sorry but you cant just say ignore the GFS.

Now if we cast are minds back again to Nov 2010 ECM was the last to pick it up.when every model wanted to flood cold air west.

I still dont think this is a done deal.

12z will be crucial i believe.

still too much straw clutching. much of it based on very shaky foundations aswell. as far as the se being colder, you only have to look at the extended ecm ens for london to work that out. i really cant understand why so many of you feel the need for definitive answers. why cant we just accept the uncertainty and see what happens. not one of the model runs you have looked at over the past few days is likely to be exactly right. maybe a few are 70% there. which one? trying to find a reason why one run is more likely than another ? logic of the mad house at the moment.

EDIT: The 12z wont be crucial. this isnt suddenly going to resolve itself in one set of runs. the pendulum could swing either way and still swing back again thereafter.

Edited January 8, 2013 by bluearmy

[NL]

In all honesty I dont think the 12z nor 18z will paint what the near or mid term future will hold with uncertainty being 'off' the scale. Still as my signature says its good to take a stab at what may happen.

[latitude]

The thing that confuses me is that the ECM Ensembles are not particularly mild, the mean remains below 5c throughout the entire run! The MetO though aren't saying mild WILL win out here, they've stressed a lot of uncertainty within their outputs and indeed from what Ian has posted on here too.

I'm not surprised they've ignored the GFS, it really is the most extreme the UK could probably get

And I thought the ECM was considerd a mild outliner the last few days and didnt match the ensemble....(think thats right, what Matt Hugo said??)

Edited January 8, 2013 by latitude

[mcweather]

The METO response to the one of the NWP picking up on the change is often to be suspicious or wait another day or so, but I think this will collapse quickly in the next 24 hours.

And yes, it’s hard to get out of the sort of pattern predicted by the ECM because you would have a strongly positive NAO and Azores High with nowhere to go.

Actually Ian the meto further outlook suggests nothing of the kind if anything it suggests a battleground situation where the possible rain in the west/ southwest could just as easily be snow.

[Chris W]

I have found the consistency of warm air advection west of the UK being modelled over the past few days by the GFS (I haven't seen too much of other models) for this week pretty encouraging, especially in light of the SSW and effects it clearly seems to be taking on the models. More experienced folk know more of course, but personally I have high confidence in strong northern blocking and severe cold coming. I doubt the 06Z GFS run will verify in FI, but oh my if it does!!!

As a short off-topic aside, lot of credit is due to those in the strat thread and others in here with a wealth of experience for their level-headed forecasts and analysis of this event.

Edit - just saw this on the Met Office site:

@bluebakermcfc Our 30-day UK outlook is indeed indicating wintry conditions for the north for the next few weeks, http://t.co/9O71ti0o ^TK

Edited January 8, 2013 by Chris W

[Shunter]

Sorry but you cant just say ignore the GFS.

Now if we cast are minds back again to Nov 2010 ECM was the last to pick it up.when every model wanted to flood cold air west.

I still dont think this is a done deal.

12z will be crucial i believe.

The 12z will be eagerly awaited today thats for sure........

Just for the record, the updated NAO table has a slight ensemble improvement to negative values today ....

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/nao.sprd2.gif

[garbagebags]

What I dont understand is the METO update was cold or very cold with snow last night from yesterdays 12z. Yesterdays evenings ECM wasnt what we wanted with regards to cold, and they didn't use that output as part of their update. So what were they using, the GFS? Now they wont even consider the GFS and are going with the ECM.

I think the MET only use their own data and models dont they?

[Timmytour]

"That ECM" was great...but didn't deliver what it wrote on the tin..

"That GFS" was superb and i really hope it does deliver.....

But should we be afraid, be very afraid, of "That Email" ?

Matthew Hugo @MattHugo81 1h

@fergieweather - Ian did you get that email?...

Confidence in a great cold spell seems to have dropped a little as far as our professional friends are concerned....does the answer lie in "That Email"?

[LomondSnowstorm]

The METO response to the one of the NWP picking up on the change is often to be suspicious or wait another day or so, but I think this will collapse quickly in the next 24 hours.

And yes, it’s hard to get out of the sort of pattern predicted by the ECM because you would have a strongly positive NAO and Azores High with nowhere to go.

We shall see Ian, you said something similar a few days ago when the GFS trended away from the initial easterly but then it was the ECM showing the most potential. I must say I'm fairly wary of the output at the moment myself but I really would not like to prejudge anything after the volatility of the last few days when none of the models have exactly covered themselves in glory. This is an instance where I'd happily sit on the fence and I wouldn't be surprised to see the models playing with a few different solutions before this is resolved.

[Rob K]

Ian Brown is right that in general, if there is model disagreement, it is the milder solution that is the correct one, whether that is ECM, GFS, UKMO or whatever. You could say that at least 9 times out of 10 just because of the balance of probability. Any one missing ingredient and you end up with mild. That's just the reality of UK climate, much as I would love something like the GFS 06Z to occur!

[Adam lufc]

Guys can anyone help me out here or am I just kicking myself for no reason. Why are all the anomalies and signals showing heights towards Greenland but the ecm going against it?? If the anomalies and signals were showing mild you can bet your bottom dollar that the charts would all show that.....??

[mulzy]

Ian Brown is right that in general, if there is model disagreement, it is the milder solution that is the correct one, whether that is ECM, GFS, UKMO or whatever. You could say that at least 9 times out of 10 just because of the balance of probability. Any one missing ingredient and you end up with mild. That's just the reality of UK climate, much as I would love something like the GFS 06Z to occur!

Where is the evidence for this? At the moment things are finely balanced between a mild outcome and a colder wintry outcome.

[TAFKAP]

"That ECM" was great...but didn't deliver what it wrote on the tin..

"That GFS" was superb and i really hope it does deliver.....

But should we be afraid, be very afraid, of "That Email" ?

Matthew Hugo @MattHugo81 1h

@fergieweather - Ian did you get that email?...

Confidence in a great cold spell seems to have dropped a little as far as our professional friends are concerned....does the answer lie in "That Email"?

I think you're starting to over analyse things a little. As good as the Meto are (no seriously!) they are not omniscient and 'that email' could just as well say the Meto are now worrying about England being covered in several feet of snow in 10 days time (unlikely, yes). This is starting to get a little silly actually and we need to stop micro-analysing every comment by every weather bod on social media and get back to the NWP output which at the moment, to take an objective view, is about as far from having it 'nailed' as it possible to be. To use an analogy the roulette wheel has been spun but that ball is still sputtering around and where it lands is anyone's guess.

[Ian Brown]

Guys can anyone help me out here or am I just kicking myself for no reason. Why are all the anomalies and signals showing heights towards Greenland but the ecm going against it?? If the anomalies and signals were showing mild you can bet your bottom dollar that the charts would all show that.....??

It becomes back to my theory about the NAO refusing to go negative for reasons that need researching in spite of the background signals being otherwise.

We can get cold without the benefit of –NAO but events such as Jan 1987 and Feb 1991 are rare beasts.

[frosty ground]

Ian Brown is right that in general, if there is model disagreement, it is the milder solution that is the correct one, whether that is ECM, GFS, UKMO or whatever. You could say that at least 9 times out of 10 just because of the balance of probability. Any one missing ingredient and you end up with mild. That's just the reality of UK climate, much as I would love something like the GFS 06Z to occur!

Following that logic, any forecaster would miss any upcoming cold spell....... Then again I can't remember too many occasion (If Any) Ian called a cold spell / Snap correctly that went onto occur. There is always an exception to the rule, even when the rule is a made up one.

[Rob K]

Where is the evidence for this? At the moment things are finely balanced between a mild outcome and a colder wintry outcome.

No evidence other than 10 years or so of looking at the models! And we know that to get a decent cold outbreak in the UK everything has to be "just so" to overcome the natural mildness of our location. Generally if one of the models spots something that's not quite right then the whole house of cards collapses in short order.

I'm not saying that will necessarily happen, just that I think it is more likely that GFS will flip towards ECM than vice versa. Fingers crossed that I am wrong though!

[snowblizzard]

Where is the evidence for this? At the moment things are finely balanced between a mild outcome and a colder wintry outcome.

Yes, but in reality it's probably 90% certain to end up a mild outcome because that's what usually happens in the UK!

And, is it really that finely balanced?

Edited January 8, 2013 by snowblizzard

[snowmackem]

Ian Brown is right that in general, if there is model disagreement, it is the milder solution that is the correct one, whether that is ECM, GFS, UKMO or whatever. You could say that at least 9 times out of 10 just because of the balance of probability. Any one missing ingredient and you end up with mild. That's just the reality of UK climate, much as I would love something like the GFS 06Z to occur!

Difference is, this time there is so much evidence weighted in favour of a severe? cold spell that your 9 times out of ten has, on this occasion probably dropped to a 4 in 10 chance of a severe cold (snowy?) spell not occurring towards the back end of next week. In all my tears of model watching I have never seen so much confidence, nee ramping, from senior more experienced commentators than now.All the ingredients are in place for the 3 course meal, starters this weekend, main course next weekend, pudding thru Feb lol

[Radiating Dendrite]

The problem is that people think cold means heavy snow and -10c temps.

The majority of the last 12 months have returned colder than average CETs - so colder weather is very much a possibility, just as milder than average is.

Edited January 8, 2013 by Radiating Dendrite

[Timmytour]

I think you're starting to over analyse things a little.

Either that or you're taking some posts too seriously

[mcweather]

No evidence other than 10 years or so of looking at the models! And we know that to get a decent cold outbreak in the UK everything has to be "just so" to overcome the natural mildness of our location. Generally if one of the models spots something that's not quite right then the whole house of cards collapses in short order.

I'm not saying that will necessarily happen, just that I think it is more likely that GFS will flip towards ECM than vice versa. Fingers crossed that I am wrong though!

I wouldn't always go with that Rob. Like you with many years of model watching under my belt i i find it is often a case of the actual outcome being a something of a halfway house between the two and to be honest a if the 06Z gfs came in even half as strong as suggested it would still be quite something.