[Model Output Discussion 1st January 2014-06z onwards.]

Again 144hr is probably as far forward as we need to look imo and again the 'overall' pattern looks fairly stable, with some pretty cold surface air in place by that time.  Yes there are shortwaves circling like sharks around a shipwreck, but that was always going to be the case, it wouldn't be a potential cold shot without um!

 

 

[Model Output Discussion 1st January 2014-06z onwards.]

Probably wise to let the run complete, or at least the high res part of it, before reading to much into any possible changes...subtle or otherwise.

[Model Output Discussion 1st January 2014-06z onwards.]

yes, and for what it's worth (probably not much but....) the CFS has been adamant for a while now that spring, especially March, is going to see plenty of blocking and undercutting - similar to the synoptics progged for next week actually.

 

 

personally i find that a bit upsetting as i wasn't really a fan of last spring but there you go. I'm getting used to cold springs, now.

Think it's coming earlier this year NFG, was actually expecting Feb, but now the last third of Jan looks increasingly like it may be back in the frame.  Looking at the shorter term I'm not yet convinced that next weeks first bite of the cherry will leave more than teeth marks or perhaps split skin, but thereafter we may see the whole thing absolutely inhaled.

[Model Output Discussion 1st January 2014-06z onwards.]

And finally we have the London ensembles:

 

 

 

Sub 5c Mean all the way from next week onwards and with the strongest clustering below the mean. We can also see that the end of the 0z GFS was an outlier compared to the ECMWF ensembles, most notably from the wind:

 

 

 

Reading through the running commentary of the 6z was actually quite entertaining. One might hope that the events of the past 48-72 hours would show once and for all not to draw meaningful conclusions from a single deterministic run for 5+ days in to the future, especially before the run has even completed. But there we go, you live and learn...hopefully the latter part of that more especially!

 

SK

You would think so SK, but No...expect plenty more '-5c 850hpa line 11 miles farther south across Surrey at 180hrs on this run' type comments over the coming days...

 

Waiting on the 06 GFS ensemble suite now, will be intertesting to see where this Op fits as the 00 run was reasonable close to the mean.

 

Edit - 06 Op one of the colder members, esp 16-19 Jan.

 

 

 

 

 

 

[Model Output Discussion 1st January 2014-06z onwards.]

Once past 120-144hrs it matters not a jot if the 06 is slightly better/slightly worse or the same. The important fact is the overall evolution remains pretty solid, as long as doesn't change any inter run variability across one particular model is unimportant. However, we will as even need to look out for shortwave development IF things remain on track as far as timing is concerned, because they will crop up as sure as night follows day. 

[Model Output Discussion 1st January 2014-06z onwards.]

144hrs is realistically as far ahead as we need to look for now imo and perhaps not unsurprisingly the 06 is less clean by then....let the shortwave drama commence, you just knew it would

 

[Model Output Discussion 1st January 2014-06z onwards.]

A few people saying the cold would not last long, I disagree, if we DO get to T144, what can the block do next? Go east and we keep a cold continental flow. Go west and we set up for a northerly. Seems v unlikely the block would go north. And even if it sinks south as per ECM, it would take several days to get back to a westerly from there. The most likely follow-on, IMO, would be for the block to hold in situ for at least a few days to the north of Scotland, meaning more of the same. But that's getting WAY too far ahead!

As ever there is no real point in discussing how long something will last before it's even arrived, especially when it's an E'erly and it's not due to arrive for 5 or 6 days. Let's see what the 06 goes for, because over the last few days it has been one of the keener GFS runs to build pressure to the NE. 

 

Just an aside...isn't it odd that when mild you can't wait to view the next updates for some hope, but when cold is progged you almost don't want to look in case it disappears again. OK, perhaps it's a personal thing...

[Model Output Discussion 1st January 2014-06z onwards.]

Last week I posted some charts to show how in 47 we went from a miserable SW pattern to a bitter E pattern in little over a week and looking at the ECM those charts are pretty much replicated by it 00 output. Given what we have seen so far through extended Autumn the latest suites look very pleasing indeed, but most if not all of us know that getting E'erlies into the UK is very rarely as straightforward as the models suggest when past T+120hrs. A significant step in the right direction though and even earlier than I expected.

[Model Output Discussion 1st January 2014-06z onwards.]

You were saying the GFS was the best model the other day?

Oh yeah....well it is again now

[Model Output Discussion 1st January 2014-06z onwards.]

Lots of cold air getting where we want it but can we get it this way, very interested as to what the UKMO’s take on this will be this evening as the GFS is millimetres off a full blown easterly on this run.

Pity it's such a poor model though, because this chart looks like we might be starting to get somewhere at last...maybe a blue moon event tho, you never know.

 

[Model Output Discussion 1st January 2014-06z onwards.]

Morning all,

 Our snow computer forecasting system upgrades snowfall in our region for Tuesday and Wednesday next week with a combined reduction in temperature at all levels. Our portal forecasts indicated a fall of pressure in Southern Europe and a rise in pressure further north with a developing cold pool over West Russia. A low circulation would seem likely during this period , probable centre about 200k south of Klagenfurt.

Looking towards the British Isle, the expectancy still holds for some fall of pressure to the Southwest next week, whether this is trough alignation or cyclonic development , it still in mid- term prognosis period. The consensus from our experts is that the British Isles may become some sort of boundary ( battle ground ) against a increasing colder block further east.

Of course it is much harder to forecast snow in your location than here in central Europe. Should make for good model watching as this week progresses.

Have pictures over here on the news of the UK flooding and Mid-West Blizzards. Quite a contrast. Warmer uppers here to today, should see some snow melt after the weekends 35cm fresh snowfall.

 C

Thanks for the update C.  Is it fair to say you/they have backed away from this to a degree?

 

03 January 2014 - 20:40

Evening, the latest ECM is almost akin to our latest scrip. It is important for cold retention that heights continue to drop to the south of the uk. A pool of cold air not far from the UK. Changes are a coming, a soggy Southern Britain could soon become snow laden landscape come the second half of the month. Will up date latest UBIMET thoughts tomorrow.

c

 

[Model Output Discussion 1st January 2014-06z onwards.]

For now there is still nothing in the NWP to suggest a switch to colder weather across the UK anytime soon, BUT looking forward Ian F has has just posted there are some colder E members that the MO are not discounting.  Given what we have seen so far this winter and more especially recently that should be good enough for most imo... but of course it never really is.

[Model Output Discussion 1st January 2014-06z onwards.]

I'm sure some will no doubt put another positive spin on the overnight models in terms of cold, indeed if you live in Scandinavia and northern Europe it is a great run, however, so long as we keep the low heights around southern Greenland / Iceland then we will be governed by south westerlies as we are for the vast majority of the ECM run. As above it looks like close but no cigar for the mid January  timeframe and we'll need another bite of the cherry late in the month to hopefully back up the Mets delayed colder spell in Feb.

 

Recm2161.gif

Indeed, I mused on Sunday that my fear was a Scandi high would develop to far east, meaning the North Sea becomes a frontal graveyard and we largely remain on the wrong side. However as I also said at the time, this kind of set up can at least bring some occasional temporary interest to easternmost areas. 

[Model Output Discussion 1st January 2014-06z onwards.]

Afternoon Draztik

 

I think maybe you should take yourself out of the GFS cacoon for a few moments...

 

 

I think everyday for at least the last 7 outlined why the GFS is 'expected' to be wrong- NB expected. As once in a blue moon it gets it correct. If by now you are still placing faith in a model that: 

NCEP regularly dismiss it: even to the point of chastising it

UKMET dont even have it ( or probably compare it to the game PONG at lunch time )

The seasoned regulars on here have no time for it...

the varification stats put it sometimes second- sometimes 4th ( & thats the BEST run- of the 4 operationals- of whcih 3 will be even worse)

 

if of course you choose to put that ahead of all the others then thats your bed-

 

 

However for those of us who set about showing to the members on here why a model is wrong-

* its known faults

* the inter run model bias

 

Then you come out the other side knowing that your backing the rank outsider.

 

 

The GFS now since the 18z through now to the 12z has been seen by most viewers on here & have seen the high'resurection' from a pancake non existant on the 12z yesterday to this today

http://modeles.meteociel.fr/modeles/gfs/runs/2014010612/gfsnh-0-180.png?12

 

A ridge with energy undercutting.- but of coursde into low res & it all goes THROUGH the block.

 

UKMO NA at this moment in time.

 

 

Am I ecstatic- not really as if you expect something to happen within a model then it does exactly as planned- all it does is confirm the ' no faith ' in that model.

 

However yourself & the other GFS die hards will have seen my post this morning changing the emphasis to %age/ confidence based commentary.

Sure the GFS only got 10%- but to be fair it only deserved 10%.

 

Hopefully from the 12z GFS & perhaps its ensembles you will have seen again how for th second week running it flails about beind the ECM/ UKMO/ JMA/ GEM- possibly even the TEITS crayon method of 1998........

 

Best regards

Steve

Despite all the above Steve the MDT has been littered by posts from your self over recent years, literally hanging on the next GFS chart and shouting from the rooftops when said chart was full of cold or cold potential, whatever the timeframe.  If you view GFS with such deep disdain, why even look at it or comment on it at all...or is it just in case that 'once in a blue moon it gets it correct' 

[Model Output Discussion 1st January 2014-06z onwards.]

What's this, jet going under?! Lows tilted NW-SE?! Good lord!

 

The GFS is dead...long live the GFS. For now

[Model Output Discussion 1st January 2014-06z onwards.]

Hi Shedhead,

 

What I would say, as the strongest possible response to your post, is that the NOAA themselves are not happy with the performance of neither the GFS or its ensemble compatriot, GEFS.  To that end, it is undergoing a major overhaul in April, in order to correct a number of errors which have been identified in the physical model.  In addition, it is also worth stating that all mathematical models generate bias, and the GFS is no different in that regard; it will - for example - display a predisposition to explosive cyclogenesis, and this is mainly due to an issue around resolution depth, coupled with a data issue regarding SST.  If you read the narrative that Nick often references from NOAA discussion, you will - quite often - see commentary to this effect.

 

With respect to the verification statistics, I would wholly disagree with your approach.  The statistical basis for verification is an accepted industry standard, and it is through that which respective model performance is objectively assessed.  There is no agenda at play; the statistical results are derived from the output of the models, so - if they don't verify - then it is the model that is at fault, not the statistics.  I think an important point to make here is that - in a scientific environment, there is no room or for that matter value, in assessing using subjective interpretation; there needs to be benchmarks and criteria, and that is what a standard reanalysis model delivers.

 

The ECMWF - in tandem with UKMO - are world-leading pioneers in meteorology, and this isn't lost on NOAA or other worldwide counterparts.  There is actually a fairly broad consensus right across the board, and I think you'd be surprised that there really isn't this competitive nature - it's a lot more scientific and progressive than that.  For example, I know that there are (at least) two ECM colleagues over in Reading who are currently advising NOAA on how to best transition from the current iteration of GFS over to the new one in April.  That's so that the NOAA have a seamless implementation of the operational model which, in time, the ECM can also make use of and naturally compare itself against.

 

My personal - and I stress personal - view of the GFS, is that it contains too many consistent and permanent flaws, in order for me to attribute it too much credit.  That is not to say that I completely discount it - that would be foolish - but it's about weighing it up, relative to its peers; there will be times when the GFS performs better, and there will be other times when it performs quite obviously poorer.  But that's mathematical modelling.  There is one model, for instance, that is nigh-on useless through the first third of winter, and that is because its physics engine relies so heavily on stratospheric data.  Thereafter, its performance appears to be quite exceptional.  It is not within my gift to say which one, but I'm sure Ian knows which one I'm referring to.  Equally so, it is evident that some models perform better through different seasons, and this can be understood through how every model will have different elements of teleconnective reasoning.

 

So, it isn't really the case that there is one model that is in any way to be considered a panacea - that really isn't the approach that is used by the Met Office (or the NOAA, for that matter)  The approach is to objectively assess all outputs, and to then apply probabilistic reasoning against it, in order to draw a forecast.  That approach abrogates against the sort of bias which is often found to be at the source of most known human errors.

 

I hope that helps, or at least serves to perhaps dispel a myth or two?

 

SB

Hi Snowballz - thanks for your clear and detailed reply. I fully appreciate what you have said and I can't/wouldn't argue with the points you made, but as I made clear from the off I was talking from a personal perspective.

[Model Output Discussion 1st January 2014-06z onwards.]

I too share the wonderment at how worked up folk can get about a model, whichever one. However your comment shed' re the statistics is about as odd as those you berate about GFS performance. I would be interested in how you can convince us in what way GFS has outperformed ECMW since the autumn and before, when the statistics for the upper flow (500mb) suggests the opposite for most instances whenever I have looked and I do look fairly regularly?

As I said John it a purely personal viewpoint, but it's primarily based on what GFS and ECM have projected outside my front door, rather than across the wider scale. Post 144hrs GFS has been significantly better all Winter so far imo, as it was across most of Autumn and a good part of Summer.

[Model Output Discussion 1st January 2014-06z onwards.]

Surprised by some of the posts this morning. Still, we lack consistency across the models, with the GEM gravitating towards GFS in its evolution. The ECM still going with heights to our NE, but its 10-15 ensembles are starting to drift towards a more zonal outlook. With gefs by Jan 20th, keeping the mean trough to our NW.

Day 10-15 heights ecm, gefs 6z mean t336

With the signal post day 13, for the signal to be a rather mobile westerly, by day 15.

So even if heights build per ecm, it appears at this juncture to be temporary.

Looking at the latest Teleconnections, theyre telling me our favored pattern will be zonal easing, a drier interlude with pressure rise, then returning to something akin to zonal.

Obviously, all hope not lost. When a block has been setup, they can prove stubborn to dislodge. But, the models indicate a quick return to zonality and that's where im headed too.(tho important to note, gfs says no to any block in first instance)

As for comment on the positive temp anomaly over Europe, gefs 0z sees a lot of the Balkans and mainland Europe between positive and average, even by day 16.

Lastly, this constant berating of the gfs by some members is really odd! No idea why projected synoptics of a model can cause so much emotion and disdain. And unfortunately, with that emotion any objectivity is thrown out the window, and posts become so bias. Its painful viewing.

latest UKMO - interesting!! Add to that the respected view of snowking.. For sure, im perplexed! obviously there are signals for settled weather within their forecast data and timeframe quoted. Wish we could see evidence of this within the medium term models, but alas..

Another excellent post Draztik and I must admit to sharing your confusion over the constant critisism of GFS. Of course it get things wrong at times and no doubt it is often more progressive and extreme re zonal pattern in particular. However as far as I'm concerned (not really interested in the so called verification stats) it has completely out shone ECM since early Autumn and it did so frequently across Summer too, especially post T+144hrs.  

 

I guess the only plausible explanation for the amount of abuse it receives is the fact it often shows what most don't want to see in Winter, but if it were a living thing I'm sure it would have successfully sued for deformation of character long ago....and won handsomely

[Model Output Discussion 1st January 2014-06z onwards.]

The new update summary just posted by my UKMO colleagues at BBC Weather Centre precisely replicates what Ops Centre are currently considering as probable outcome:"Monday 20 January—Sunday 2 FebruaryStaying unsettled... at firstWhilst current indications point towards unsettled weather persisting through much of the rest of January, conditions are expected to be more typically unsettled for the winter season. Certainly early in this fortnight the pressure looks set to remain low to the southwest of Iceland.However, and this would be quite a change for this winter, there are some signals emerging for an increasing risk of a change to colder weather types towards the end of January. This would increase the potential for more settled conditions, leaving a lower risk of wet and windy spells than has recently been the case."

Thanks Ian...everything remains on track then, just hope it actually delivers for the last third of Winter.

[Model Output Discussion 1st January 2014-06z onwards.]

No change across Europe for the next 8 days which takes us to the half way point of winter on the 14th with the majority of Europe staying above average

 

 

Average temps left expected temps right

 

Clearly we don't have to like it, but I guess we do have to admire the sheer persistence and strength of the European warmth anomoly this winter, because it is now starting to look pretty damn impressive...and much of continental Europe looks set to become even warmer this week!!

[Model Output Discussion 1st January 2014-06z onwards.]

Not really a lot that can be added to what's already been covered by Gibbys excellent post, but from a personal perspective I'm becoming increasingly encouraged by the big 2's want to build pressure and dry things out, especially next week...happy to see that develop first, then worry about cold afterwards, but how welcome would a week of strong easterlies be to suck up some of this moisture? 

[Model Output Discussion 1st January 2014-06z onwards.]

yes all 3 main models suggest what forecasters call a confluent upper trough in about the same place on all 3. From these, surface features can run just ahead of it giving a fair amount of rain, so Met will certainly be watching this probability and their Fax charts show this type of pattern at the surface.

Indeed John, might well be out of the frying pan and into the fire this week, especially for this neck of the woods...hopefully Ian might also be able to shed (no pun intended!) some light on the risks as the MO currently see them.

[Model Output Discussion 1st January 2014-06z onwards.]

My purely imby'ism concern right now is how wet is it going to be in the south this week.  Lighter winds are all very well, but not if what looks like a potentially troublesome trough gets stuck over or close to the English Channel as a result...this really isn't the kind of setup I want to see come midweek... 

 

[Model Output Discussion 1st January 2014-06z onwards.]

OK, not really model related, but as it's quiet.....you gotta ask yourself if this is preferable over what we have? 

 

URGENT - WINTER WEATHER MESSAGENATIONAL WEATHER SERVICE BISMARCK ND352 AM CST SUN JAN 5 2014...LIFE THREATENING WIND CHILLS TODAY THROUGH MONDAY....VERY COLD ARCTIC AIR WILL CONTINUE MOVING INTO NORTH DAKOTATODAY AND WILL REMAIN THROUGH MONDAY. LIFE THREATENING WINDCHILLS TO 65 BELOW ZERO ARE EXPECTED TODAY THROUGH MONDAY.

FROSTBITE CAN OCCUR IN 5 MINUTES OR LESS WITH THESE WIND CHILLS.AVOID OUTDOOR ACTIVITY. 

[Model Output Discussion 1st January 2014-06z onwards.]

Indeed Shed and had this forum been around then there would have been much despondency, strong PV, big euro high I won’t use the B word, just goes to show what can happen. However things right across the NH were different then, arctic ice extent for one thing, back then sea ice coverage in August was as great as it is now at its greatest winter extent, so the winter ice pack back then must have been vast, I’m sure someone can find some data on that. My own theory and I stress that. Is that there is a correlation between winter sea ice cover and the prevalence of HLB across Greenland and Scandinavia and I seriously doubt if we could get another 47 or 63 unless that changes, leastwise our odds against it are substantially greater now. That of course doesn’t mean we can’t get HLB at all as recent years have shown, just that it’s less likely, certainly less likely to be of that extreme nature.

The 06z is out now but it’s done nothing to change my mind, although post mid range it looks substantially different from the 00z, the central theme remains, zonal, MLB, back to zonal, although there are again some hints at HLB it never really gets off the ground and only has a minimal impact on us.

Couldn't agree more weather eater - things were very different back then, indeed Dec 46 was nowhere near as zonal across Europe, with bitter E'erlies even reaching the UK at times....

 

Frankly my fear is a Scandi block will set up for the 2nd half of Jan, but probably just to far east, with the North Sea becoming a frontal graveyard. That kind of set up may well bring some interest at times to eastern areas, but Feb is still to month to watch imo. Interesting times ahead, with the worst now soon to be behind us, but still a good deal of patience will be required imo.