Model Output Discussion 18th Nov.2013-12z onwards.

[Cecil Hogmanay Melchett]

Morning-I am still very troubled this morning by the large disparity between the UKMO and the ECM.What is worrying is 2 fold* Whilst the ECM is the best resolved model I dont think I have seen 1 run of any model amplify the energy (now at 144) and take it west of greenland-This is crucial to the ECMs success and its been uber consistent with that outcome on 5 of the last 6 runs-* The second worry is the UKMOs halfway house solution of 'somewhere in the middle towards iceland' at day 6 will see a quick warm spike for england after just 36 hours of northerlies, although the cold may return south quickly again as the back edge passes through- there is also a way to longer term cold if this comes to fruition but lets wait for now-So im holding station today and waiting for the 12s UKMO-I am concerned today though- of interest will be the ECM ens especially the control.RegardsS

Yep,its very confusing and a bit concerning this morning steve.

The GFS is blinkin awful but looking at the ensembles it does look a wild outlier from ver early on,that said,maybe the rest of the pack are behind the 8ball.

UKMO is also poor moving forward,probably a 24 to 36 hour special and not a great deal to be excited about either for most.

That leaves the ecm,normally i'd be delighted to have the ECM on board but its poor form in the last fail has left me questioning its reliabilty to be honest,this will be a big test of its supremacy.

 really dont know how to feel this morning,probably concerned is the best way to describe it..

[itsnowjoke]

Ramping is half the fun on here, and never needless... Its a weather forum not a forecasting tool. Go watch the BBC weather if you want a sober reflection on the weather

#gotoutwrongsideofbed. sorry mods.

[terrier]

Reading between the lines I would think we will see half way house between ukmo and gfs model. I have no confidence in the ECM model think it's going to fail again in my opinion

[UV-RAY]

Yep,its very confusing and a bit concerning this morning steve.

The GFS is blinkin awful but looking at the ensembles it does look a wild outlier from ver early on,that said,maybe the rest of the pack are behind the 8ball.

UKMO is also poor moving forward,probably a 24 to 36 hour special and not a great deal to be excited about either for most.

That leaves the ecm,normally i'd be delighted to have the ECM on board but its poor form in the last fail has left me questioning its reliabilty to be honest,this will be a big test of its supremacy.

 really dont know how to feel this morning,probably concerned is the best way to describe it..

Until the UKMO are on board then all talk of a wintry wonderland this time next week need to be kept in check, the form horse does still looks like 2-3 days of cold uppers at least, with snow more than likely for our Scottish friends more so those towards the NW. The rest of us well it's a case of more data is needed, on the plus side there's still lots of time for upgrades, downgrades and lots in-between.

[Newberryone]

I get the feeling this morning that the ECM is leading us all up the garden path again. Remember if it looks too good to be true then it probably is. Me personally think this will be a Scotland only event and I expect the gfs to be correct again with the ECM coming kicking and screaming into line with it like it did just a few weeks ago

 

Probably an ill-informed take on these charts but if this is just to be a cold snap as opposed to spell I hope the GFS verifies for the Dec 10th ECM chart has us under the influence of what looks like a very boring anticyclone which I doubt would deliver anything other than average/mild temps by then

[BLAST FROM THE PAST]

Looking through the thread I was surprised, until I read Big Steve M's response, that no one was mentioning the UKMO.  It is not supporting ECM and would go more towards the GFS option.

Like I said last night I can see where the GFS is coming from mid-term and I don't side with the 'cleaner' option of the ECM, as it has been mentioned before the UKMO backing does seem to be crucial on many fronts.

What is of note the ECM collapses its cold outbreak quite quickly too......for me that is a decent hint? 

Lets hope, for coldness sake, its clean though.

 

 

BFTP

Edited November 30, 2013 by BLAST FROM THE PAST

[terrier]

Sometimes I don't understand why the gfs gets so much stick for. To me it seems to be out performing the ECM every time at the minute. And for the ukmo to be backing the gfs solution this morning is a big coup

[No Balls Like Snow Balls]

Bit confused with the depression on here this morning. There was never meant to be a sustained severe cold spell next week, so why be depressed with something that is never meant to happen.

UKMO and ECM still looking good for much colder weather to arrive by the end of the week.

[Paul White.]

Reading between the lines I would think we will see half way house between ukmo and gfs model. I have no confidence in the ECM model think it's going to fail again in my opinion

Hi terrier I don't want to get into a huge argument with you especially as you have the name of my fave football club. But I do find it surreal that you have more confidence in the GFS than the ECM. Two things I would like to point out the GFS is lower than the ECM in verification stats. And secondly the run to run consistency from the GFS recently has looked poor in my eyes it has looked as though every run has produced a different outcome. I don't know if you are basing your lack of confidence on two failed ECM runs in the last 15 months if that's the case there will be many many more GFS failures. All I can say is I like it when a model latches into a signal and runs with with it until resolvedPaul

[lamppost watcher]

Brian Gaze's comment this morning....

There look like 3 outcomes late next week. Cold spell, cold snap or it stays milder! The computer models are having difficulty pinning down the pattern which develops across the UK and Western Europe.

I’m still favouring a cold snap with the most wintry conditions in the north. A cold snap I’d define as lasting a few days.

Nonetheless, I’d say the chances of a cold spell have increased, as have the chances of it remaining milder, especially in the south.

So to conclude, it’s now looking like a 3 way race, with cold snap remaining the favourite.

[Snowman.]

Sometimes I don't understand why the gfs gets so much stick for. To me it seems to be out performing the ECM every time at the minute. And for the ukmo to be backing the gfs solution this morning is a big coup

UKMO isn't 'backing' it 100% its showing energy riding over rather than up the side.

 

Meanwhile the GFS is just piling it over not even giving the south a northerly.

 

GFS gets a lot of stick because its flips and flops when a pattern like this comes within mid-range and usually goes with its bias and overdoes or underestimates something usually it underestimates the strength of a block and decides to send it tumbling down, other instances it will over do the strength of a low you would have probably heard about that anyway that the GFS FI produces a monster low and sends it in like a steam roll.

 

We tend to go more towards the ECM as it outperformed the GFS during difficult times.

 

We should wait until the 12z suite before we start judging the future circumstances. 

[bluearmy]

Sometimes I don't understand why the gfs gets so much stick for. To me it seems to be out performing the ECM every time at the minute. And for the ukmo to be backing the gfs solution this morning is a big coup

not according to the stats it's not.Rather than relying on anecdotal memory, you can have look through every run over the past few weeks on meteociel on every model. Of course, gfs running twice as often has more chances to pick the correct solution. I expect you'll find it had more chances to pick the incorrect solution!of course, looking post day 7/8 is not a good idea as the operationals are not meant to be used at those timescales without the ens.

[A.J]

Bit confused with the depression on here this morning. There was never meant to be a sustained severe cold spell next week, so why be depressed with something that is never meant to happen.

UKMO and ECM still looking good for much colder weather to arrive by the end of the week.

I think the issue is that some members get caught up and hooked on the well-intentioned ramping posts showing the more extreme solutions and when subsequent model runs are missing these extreme solutions there is natural disappointment....Saying that, it should be noted that this thread by its very nature is discussing possible scenarios which may or may not verify...After all, it's the current weather patterns which dictate the future model outputs, not the other way around 

[Cloud 10]

The differences between gfs and ecm at just 96 hrs are the same as the last few days with

the gfs wanting to send energy over the top of the atlantic high,whereas the ecm sends it north.

 

gfs..  ecm..

 

 

 

 

[Matty M]

A stronger shift towards milder solutions after Sunday the 8th on the latest ECM ENS output.

 

With only circa 20% going for a colder solution at this point.

 

Good consolidation (75% support)  for a significant cold snap (Friday 6th+Saturday 7th)

Edited November 30, 2013 by Matty M

[Summer Sun]

Looking at the ECM ensemble its 3 cold days max before less cold air comes in from west

 

 

t216 and t240 sees less cold air moving across the UK

 

 

GFS ensemble is also in support of less cold air coming in

 

 

At t144 UKMO has -12 850's over northern Scotland

 

 

ECM has -8 850's

 

 

GEM has -6 850's over Scotland with -8's just approaching the far north

 

 

GFS has -8 850's

 

Edited November 30, 2013 by Summer Sun

[radiohead]

I suspect we'll end up with something more cold than what the current GFS shows, but less cold than what the current ECM shows. Either way, it's only going to be a 2-3 day spell of weather, the severity of the cold and the degree of wintry precipitation is what remains unknown.

[cooling climate]

Must admit the ECM run this morning does look a little suspect in the way it finds that

extra bit of amplification out of nowhere between t96 and t120.

The ECM model is known for over doing blocking patterns further north as I'm Dreaming

Of said so lets hope this is not one of these occasions.

The 06z run may not tell us much but the 0z ens from the GFS did not look bad at all in

my opinion.

[karlos1983]

Interesting that neither the GEM or GFS are interested really from the 00z. So do they perhaps have a better handle of what is going on over the other side if the pond, which ultimately will impact the Cold spell next week. ECM and UKMO being European models perhaps not getting a proper handle of the situation. I guess the same could be argued as the situation develops closer to home?

[Weathizard]

Must admit the ECM run this morning does look a little suspect in the way it finds thatextra bit of amplification out of nowhere between t96 and t120.The ECM model is known for over doing blocking patterns further north as I'm DreamingOf said so lets hope this is not one of these occasions.The 06z run may not tell us much but the 0z ens from the GFS did not look bad at all inmy opinion.

Agree entirely. I personally am backing a halfway house GFS/UKMO solution, which could well still be a nice 48 hour cold shot but the high will rebuild its way in from the west and bring more settled, 'milder' conditions. My reasoning for backing the GFS more here over the ECM is as said above, I find the ECM's solution & way it gets there looks very strange & it tends to have a large bias towards HLB during winter, we'll see though but I'm firmly in the GFS/UKMO 50/50 boat

[SLEETY]

Brian Gaze's comment this morning....There look like 3 outcomes late next week. Cold spell, cold snap or it stays milder! The computer models are having difficulty pinning down the pattern which develops across the UK and Western Europe.I’m still favouring a cold snap with the most wintry conditions in the north. A cold snap I’d define as lasting a few days.Nonetheless, I’d say the chances of a cold spell have increased, as have the chances of it remaining milder, especially in the south.So to conclude, it’s now looking like a 3 way race, with cold snap remaining the favourite.

Well that statement is incorrect.It's the gfs that has been having the difficulties going from mild outliers to cold outliers.The Ecm has been rock solid ,but a lot of people seem to think it is wrong,because it doesn't match the UKMO EXACTLY at t+1444

 

The UKMO could be correct,but it's been miles out several times before.I remember a cold spell quite recently which the ecm picked up way before the met model,and it  was several days later before the met model came into line.And ended up with East Suussex and Kent getting snow from a front moving West  to East.

[Cecil Hogmanay Melchett]

Doesnt look like gfs will be backing down...

[Catacol]

Bit confused with the depression on here this morning. There was never meant to be a sustained severe cold spell next week, so why be depressed with something that is never meant to happen.UKMO and ECM still looking good for much colder weather to arrive by the end of the week.

 

Agreed. And while many are talking of interpreting the models and removing their bias and that sort of thing - it must be remembered that the profile in the atmosphere above 500hPa is not supportive of high lat blocking and therefore long term cold. For all the increased vertical resolution the models are still not great at factoring this in, and therefore we get runs that promote a solution that is not backed up by the 3D image of the air above us. The word "disconnect" has been used on here recently - I do not have a memory or a database that goes back a long way but I have to say again that I am yet to see a sustained winter cold outbreak occur without the support of the stratospheric output. Is the concept of a "disconnect" a myth?

 

What we are going to get is a deflecting hit of cold air that will quickly be wrapped back up north as high pressure builds once again at mid latitudes because it cannot build further north due to the strength of zonal winds above 500hPa. This is the scenario that many have put forward in the last few weeks. the only surprise to me is that the mid lat high is not in the atlantic and seems to want to sit right over us... and that is bringing stagnant conditions rather than the damp NW flow over the top of an atlantic ridge that I expected.

 

Those that get 36 hours of proper cold enjoy it. For those like me looking for a proper cold spell we are still straining to see over the horizon. The strat output today has not magnified the wave 1 warming that was forecast yesterday at 240h, and I fear by tomorrow that we will find that therefore this warming fades once again after a brief peak in 9 days. That will translate to yet more amplification in the global pattern through December, but not the kind of split or wrecking of the vortex pattern that we need to see. There is plenty of time yet... but for now we wait and hope that most of the composites that suggest a lack of stratospheric warming this winter are wrong. I for one do not want to suffer a strong westerly winter after all the predictive model fun we have had since 2008.

[bluearmy]

Catcol, a couple of winters back the upper strat and trop were not in sync. Whether other factors not present at the moment were at play I don't know. To get a strong sustained neg AO without strat support would seem a reasonable assertion but to say we can't have a cold spell, especially with min solar input is, in my opinion, wide of the mark.

[Paul]

Going to be closing this one shortly ready for a fresh new thread..