Model Output Discussion 1200 hrs 15/11/14

[Polar Maritime]

Enough bickering please! I have just had to delete and edit many post's, Let's put an end to this, And continue to discuss the model output in a grown up and respectful manner. What a shambles...

 

Any more off topic posts or one liners will also be deleted . So if your post goes missing you know why.

 

Many Thanks, PM

Edited November 15, 2014 by Polar Maritime

[Tim Bland]

A nice scandi high and Easterly from the CMA at day 10. Anyone know how well this model has been performing? I don't read much on here about the lesser models Eg the NASA model, Is that not worth an occasional gander?

http://www.meteociel.fr/modeles/cmae_cartes.php?&ech=240&mode=0&carte=0

[shaky]

The push west continues on the 18z gfs!! Very slightly further west at 78 hours!!

[nick sussex]

Lets hope the GFS 18hrs run cuts out too much drama, the best route to cold especially in the UK is one with as few steps as possible.

 

So we want to see the following:

 

The pattern over the eastern USA to be more amplified at around T144hrs, the ridge ahead of it to get as far north as possible, as the troughing exits the USA it digs far south, this pushes the high further north, at the same time want to see a shortwave cut se near Denmark or the Low Countries, as this clears we get our high to the nw and higher pressure to the ne joining forces, we then wait for cold pool to move sw.

 

It's important to get high pressure as far north as possible otherwise the cold pool gets directed too far south,we await the GFS verdict!

[damianslaw]

Attention remains on developments over the other side of the atlantic - models appear to be picking up a signal for an increasingly amplified pattern over eastern seaboard of USA and Canada - as opposed to just a couple of days ago, knock on effect an ineffectual atlantic coming unstuck against a stubborn block to the east.

 

BBC update shows two possible scenarios for later next week, one is high pressure sat to the NE and low pressure to the SW with a SE flow, the other high pressure more to the north and north west with north easterly and easterly airstream - how different to what the 21:55 forecast was saying just 2 days ago with its quick dismissal of an easterly outbreak and instead a SW flow.

 

We've seen many a time before how the models can get longer term pattern changes right well beyond reliable timeframe, then drop them as they come closer to medium timeframe i.e. around 8-10 day timeframe, only to backtrack and run with the pattern change theme within reliable timeframe , and run and run.. is this one of those times.. quite possibly.

[chionomaniac]

Since posting the anomaly charts yesterday there has definitely been a trend today to keep the lower heights further west and ridge buliding over the UK.

 

NAEFS

 

 

ECM

 

 

It may not lead to a northerly and I suspect that we wont see a Scandi trough just yet, but at least more settled weather will bring something more seasonal. Again, if we get some WAA in the right place then we may even get the unfavourable split turn into something more favourable. Will definitely need to keep an eye on the strat wave 2 forecasts because we could get a reinforcement of the split from this type of pattern.

[Methuselah]

^^ And could a NE flow ensue? Of course it could. So let us all hope, eh? 

[nick sussex]

The GFS 18hrs is far too flat upstream and also phases low heights with the troughing over Greenland. Around T114hrs you'll note that little green area of lower heights west of Ireland, compare what happens with the ECM between T96 and T120 and then the GFS 18hrs.

 

As soon as this parcel of energy phases it starts pulling energy over the top, this small difference is important.

 

Before then though it all unravels because we don't see that dig of energy into the Atlantic, it will need a miracle to save this run now.

 

It's difficult enough to get to cold so I'd say at this point we must see a complete clearance of energy as the low to the sw of the UK heads south, so for newbies no little patches of green left over to the west of the UK. The ECM takes a shortwave sw which phases with the low to the sw and not nw.

Edited November 15, 2014 by nick sussex

[Eugene]

Quite on the warm side really

 

 

No near average 2M temps actually, might be on the mild side though at night if its cloudy, as Steve Murr says I think ECM 12Z OP is on it's own tonight, I think GFS will be nearer the mark with a mild aloft SE'ly feed for Thursday/Friday with maybe a cold front moving slowly E'wards on Friday/Saturday introducing clearer cooler air from the NW, could stall though and be mild/cloudy but definitely not record breaking or anything that mild(early to mid teens max's)

[summer blizzard]

Lovely model output tonight delaying the Atlantic and providing scope for home grown cold. The Euro and Parallel even ignoring FI highlight this well.

 

 

[gottolovethisweather]

Since posting the anomaly charts yesterday there has definitely been a trend today to keep the lower heights further west and ridge buliding over the UK.

 

NAEFS

 

get_orig_img-1.gif

 

ECM

 

get_orig_img.gif

 

It may not lead to a northerly and I suspect that we wont see a Scandi trough just yet, but at least more settled weather will bring something more seasonal. Again, if we get some WAA in the right place then we may even get the unfavourable split turn into something more favourable. Will definitely need to keep an eye on the strat wave 2 forecasts because we could get a reinforcement of the split from this type of pattern.

 

Good to see your level headed views of the outputs in here Chio as ever, most informative.

 

For those wanting to know what might happen in our small patch of the globe in some six to seven days (FI probably as close as t+96 right now I'd suggest) tonight's 10-dayer from the Beeb hinted at two scenarios for next weekend.

 

• Firstly scenario one was where the omnipresent trough remained positioned a few hundred miles due West of Ireland with a blocking Euro HP cell over central parts of Europe. End result near average Temps and some largely dry conditions around for a few.
•  
• Second scenario offered up at t+168 hours plus was a trough positioned due SW of the UK, more like over the Bay of Biscay area and the HP blocking due North of the UK between Greenland and Iceland - End result a potential Northeasterly flow from Scandinavia, yes please! 

 

The BBC forecasts have UKMO backing as far as I am aware so I'd strongly hint that a much better setup is a coming for the final third of November. Right now, the Atlantic is NOT in charge and deep cold weather is also NOT ariving during the next five days. Beyond that though, there is hope for something better but we need to hear the extended details before jumping on board any cold train.

 

Before all the above materialises, a fair bit of nuisance rain rotating around the UK over the next three to four days, at least with Tuesday potentially dry. Overall however, as a coldie I am happy to see the much paraphrased "building blocks" being out in place but that's all it is right now, give it time. 

Edited November 15, 2014 by gottolovethisweather

[Captain Shortwave]

The GFS 18hrs is far too flat upstream and also phases low heights with the troughing over Greenland. Around T114hrs you'll note that little green area of lower heights west of Ireland, compare what happens with the ECM between T96 and T120 and then the GFS 18hrs.

 

As soon as this parcel of energy phases it starts pulling energy over the top, this small difference is important.

 

Before then though it all unravels because we don't see that dig of energy into the Atlantic, it will need a miracle to save this run now.

 

It's difficult enough to get to cold so I'd say at this point we must see a complete clearance of energy as the low to the sw of the UK heads south, so for newbies no little patches of green left over to the west of the UK. The ECM takes a shortwave sw which phases with the low to the sw and not nw.

Hilarious how it goes so wrong....

and then goes so right 

 

Lets see what tomorrows model output brings

[TEITS]

I cannot believe the change in the model output as I haven't viewed the models as regularly as I normally do.

 

http://www.wetterzentrale.de/pics/Rtavn2401.gif

 

Just goes to show how quickly these models can change. If this output continues then the Met O will have to change their forecast which has constantly referred to mild, unsettled SW,lys.

[Mucka]

Mucka maybe you & knocker want to look at the T2m ECM 12z ensembles to revisit your thought pattern

Wasnt you 'all in favour of mild atlantic just 24 hours ago'

?

 

Nope. I was in favour of pressure being eroded over Scandi and getting a trough there rather than hanging hopes on a slider and undercut since there was too much PV energy leaking under SW tip of Greenland for me. I always said that even if we got a zonal period it would likely be brief though it is true I fancied a stormy period later at one stage before the ScEuro ridge proved so stubborn. 

Once that happened I fancied the sort of pattern that is being modelled now and said as much before it appeared in tonight's output.

Think you must have me mixed up with someone else Steve. 

 

Not sure what ECM 2M temps have to do with anything I posted but never mind. I read my comment back and it looked like a jibe but it wasn't, just a little tongue in cheek humour so you are entitled to fire back.

 

There are too many sycophants here to take on anyway.

[Cloud 10]

The 18z GFS "normal" has spat out an easterly in FI,and it ain't a warm one.

 

[seabreeze86]

Here come your miracle Nick

 

http://modeles.meteociel.fr/modeles/gfs/runs/2014111518/gfs-0-240.png?18

 

The way it evolves is shaky at best, this could be called That 18z

 

Expect a million and one solutions while the models figure out the pattern other the next few days.

 

 

The new GFS not looking to bad at 240hrs 

 

http://modeles.meteociel.fr/modeles/gfsp/runs/2014111518/gfs-0-240.png?18

 

Will it be a new trend to replace the scandi high with a trough, who knows but great model watching so early in the season.

Edited November 15, 2014 by seabreeze86

[ukpaul]

Anyone know the details of why the parallel run has been put on the naughty step?* It looked more consistent in the high resolution part.

 

*(as in taking over postponed until Jan)

 

EDIT: as for the pub run, a Scandy to Greeny high classic, the sort of chart that has reload written all over it.

Edited November 15, 2014 by ukpaul

[Jason M]

I've seen worse charts at 240

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=240&mode=0

followed 24 hours later with a textbook scandi high.

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=264&mode=0

The thing I like about this is that its at day 10, not day 15.

Jason

[Cloud 10]

Well,here comes the GFS  P   which looks like going down a similar route as the ECM 12z op...

 

 

 

....and there we have it,not often you see that sort of agreement between day 10 operational runs!

 

ecm..  gfs..

Edited November 15, 2014 by Cloud 10

[nick sussex]

Just to elaborate on my previous post, and especially for newer members small differences can have big impacts, things that globally seem tiny differences do impact greatly on some patterns.Here is the GFS 18hrs run at T96hrs, note that litte wave there circled red:

 

 

This then goes nw:

 

 

And then phases with troughing near Greenland

 

 

At this point the troughing will then start to go more ne with energy spilling over the top.

 

Now the ECM T96hrs, you'll see that shortwave circled red:

 

 

The ECM takes this sw which phases with that low to the sw, note also the ridge has extended further west:

 

 

 

This phasing alone won't finish off cold chances as long as the upstream pattern was more amplified however here you get the double negative this phasing and the flatter upstream pattern. Regardless of what the GFS manages to pull out of the bag later on you're already on dodgy foundations.

 

People might think why am I bringing this up when the GFS has performed a miracle to something interesting, the point being that with UK cold spells you need as few extra problems as possible, the best route is the easiest and cleanest transition, the quicker the cold is modelled to happen the better. For this reason I'd be wary of having too much faith in output at T240hrs when the start is already shaky.

 

It might happen that way of course, but I'm known in here for being a bit picky and looking for issues as experience tells me this is a good way for deciding whether a cold spell modelled goes into my green, amber or red warning system!

Edited November 15, 2014 by nick sussex

[chionomaniac]

Ha! I always think that it is a momentous occasion the first time a model shows the -10ºC 850 isotherm reach the UK in a season and today was that day. Granted it is th GFS pub run and well into FI, and only brushes the east coast of Scotland, but it was there for a moment!!!

 

Back to the +10ºC isotherm tomorrow!

[Jason M]

contrast with the parallel 240 chart. Scandi low!!!

Both routes = cold but it does illustrate why its a bit premature to get carried away!!!

Jason

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=240&mode=0&runpara=1

Edited November 15, 2014 by Jason M

[Jason M]

The parallel is a true Cobra run!!!!!!!

Now we have some consistency between the two GFS runs, albeit the route there is different. I like this chart even more than the 'normal' GFS.

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=288&mode=0&runpara=1

Jason

drool!!!!!!!

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=288&mode=0&runpara=1

Even better is this one!!!! Pub run special tonight :-)

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=324&mode=0&runpara=1

Edited November 15, 2014 by Jason M

[lorenzo]

I think that tonight's modelling displays a couple of things - 

 

1 We are not truly rid of the King model achilles heel -  ECM amplification bias, hence the distrust in the pot of gold direct WAA runs, we have the 100hPa strat displaying the parameters of the split and a difficult block to our East to model.

 

2 More positively - we are establishing / already established  a different base state whereby HLB and 'tendency' to blockier outlooks killing the Atlantic are already a theme. Simply put he jet wants to dive and create slider lows, dial into Iberia.

 

What is massively encouraging and what sits well within analogs is that we are so early in the season,  it's November !

 

Here are a few random plots from last Winter showing where we were at in the face of a hopeful OPI wave 1 and 2 intrusion to upset matters - 

 

Sorry for the scatter charts, they are from a random folder of the general state of play last season.

 

I fear that within model runs we are yet to lose the GFS eastward bias, nor have we seen the end of ECM amped output so this must be considered.

 

The parallel GFS capped the extension of ridging vs the GFS, therefore worth a watch, esp thru ensembles, I think the GFS new is smashing any GFS run and going to GFS first is folly.The positive NAO which is on point and actually beneficial is not unexpected.

 

We have a unique set of background states, numerously pre-disposed to throwing up blocks.. It's going to be a great winter, vortex is caned... don't fear the NAO + November 

 

[Barry12]

The really good trend is that on most of the operational models today we eventually end up with an Easterly by at least day 10.

 

ECM gets the Easterly in the earliest at day 5:

 

 

GFS 18z gets it in at day 10:

 

 

GFS Parallel at day 6

 

 

 

Hopefully this trend continues tomorrow!

 

Will be interesting if the UKMO tomorrow also joins the Easterly brigade.

Edited November 15, 2014 by Barry95