Model Output Discussion

[snowmadchrisuk]

No comments on the ECM ensembles tonight . I am taking that is because they are not that great , there are some colder members though.

[Optimus Prime]

All the synoptics are so much different to the usual easterly stuff we see forecasted, this would be an amazing setup to be just thrown away plus have we ever seen the ECM model anything like this setup since we've been on netweather?

No we've never seen the ECM show what is an exceptional blocking setup comparable to good ole '62. At the same time the ECM isn't great at trend watching but is good in fixing what the GFS gets wrong. The UKMO model...well I don't really like it.

I'm sure the GFS has got this right. At the end of the day the GFS is a higher resolution model and also has more runs to fish out any inconsistencies.

I'd give the ECM a 1 in 3 chance of getting this right.

[BLAST FROM THE PAST]

Hi Blast,

How can it even be called a shot across the bows if we end up with the ecm solution which is just for a dry fine week with sunny periods and overnight fog & frost, it's the type of weather we could easily get in oct/nov and winter..normal.

It will be cold Frosty,not mild or cool BUT cold and severe cold won't be too far away. Its not to say the 12z ECM is spot on but one must anticipate the less extreme events shown by GFS. The mega cold has never been inside t144....that says a lot. Lots of frost, snow for some....but I really believe milder/less cold as we hit Christmas hols. If I'm wrong then Happy Days...if not...a fair cold spell with real anticipation for early New Year through Jan as what we are seeing is the building blocks positioning themselves rather nicely.

I mentioned the other day that the current longish stretch of solar inactivity helping to buckle and send the jet south and that we'd see tha cold spell but to look for signs of activity as that would help show signs of interruption to the cold setup. We activity starting to show again

BFTP

Edited December 10, 2009 by BLAST FROM THE PAST

[snowmadchrisuk]

If the gfs is wrong then it's a major kick in the teeth for the much congratulated parallel model which may turn out to have been consistantly wrong instead of right, maybe we have been backing the wrong horse all along.

Frosty do you know where exactly the ECM ensembles are for : http://www.knmi.nl/exp/pluim/Data/PLUIM_06260_NWT.png

It would really help me figure them out :lol:

[John Snow]

I think the end result will be something in between the ECM and GFS

Not the country paralysing blizzards of the GFS but not the cold dry with a bit of wintry mix ECM

[Frosty.]

It will be cold Frosty,not mild or cool BUT cold and severe cold won't be too far away. Its not to say the 12z ECM is spot on but one must anticipate the less extreme events shown by GFS. The mega cold has never been inside t144....that says a lot. Lots of frost, snow for some....but I really believe milder/less cold as we hit Christmas hols. If I'm wrong then Happy Days...if not...a fair cold spell with real anticipation for early New Year through Jan as what we are seeing is the building blocks positioning themselves rather nicely.

BFTP

Thanks Fred :lol:

Anyway, the much anticipated 18z is almost upon us, will it back down or keep steaming ahead towards an arctic snow fest. Whatever the 18z shows probably won't be too important, the 00z runs will be though!

Frosty do you know where exactly the ECM ensembles are for : http://www.knmi.nl/exp/pluim/Data/PLUIM_06260_NWT.png

It would really help me figure them out

Netherlands by any chance, the models are really confusing me now, think I will just hope for the best in the morning, if there is 140 online at 7 am it might be good news.

[Ross B]

I realise we are between model runs folks but that does not excuse the completly off-topic posts.

People will want to try and catch up on today's developments later and it would take hours if we didn't remove them. PLEASE think twice before posting!! :lol:

[Harsh Climate]

Thanks Fred :lol:

Anyway, the much anticipated 18z is almost upon us, will it back down or keep steaming ahead towards an arctic snow fest. Whatever the 18z shows probably won't be too important, the 00z runs will be though!

Netherlands by any chance, the models are really confusing me now, think I will just hope for the best in the morning, if there is 140 online at 7 am it might be good news.

I dont believe them esembles for a moment, hardly one run reaches -10hpa. Places like holland are pretty muched nailed on to reach -12hpa to -15hpa at some point.

[MR EXTREMES]

I think after this we need to look at the reasons why we cannot get stable High latitude blocking in the winter months, yes the ECM has chopped and changed but the evolution now looks very plausible and the other models are now trending to move the High back SE.

A very sorry episode for the GFS in particular. Best to make the most of at least a more seasonal feel before the return to Atlantic weather.

absolutely the ecm was the most consistent from the start so theres no reason to suspect its wrong and it is the top model out of them all,

and most of the more expert people are not giving there thoughts its easy to side with the models that give us what we want.

so its better to be realistic,

from tonights ecm there will be colder air but nothing very wintry apart from fog and frost and nice sunny days,

this was always the risk with such lovely recent outputs.

but ecm is number one in the charts i dont really know how the gh will effect us in the future i have a bad feeling this may well lose its grip aswell.

but it is still early days im sure gp would agree that this event was a close call,

but we all know that theres a chance of another shot perhapes a little later in the winter,

like suggested mid january.:lol:

[SMU]

Well ..........

Ive got to LOL at some of the comments on here- its definatly united we stand divided we fall on here.. ( for some anyway..)

So onto todays models- I mentioned this earlier-

we have seen a very subtle shift over night in the jet energy distribution around 140- we see a lot more flow moving along the iberinan Peninsula & less energy into the loop jet over scandi- as a result that huge pulse of cold air starts to look a though it may not make it. However on the plus side the jet pushing along the southern flank in a surpressed regime is likely to strenthen the Easterly to start with & begin to elongate the troughs over spain & portugal- Whilst this is a slightly risky pattern as it does bring the 0c isotherm back North it also brings a higher potential for a BIG snow event-

Just to summerise whats happening is the speed of the flow coming off the states & the distribution of energy going into the Northern Arm-

If we cast our mind backs X2 days we were all getting excited at the prospect of a fleeting Easterly ( Mostly going into France) then the large trough coming roaring SW through Scandi introducing that -15c / -20 airmass-

This is the 12z run from the 18th- It should link to the jet stream-

http://91.121.94.83/modeles/gfs/archives/gfs-2009120812-5-144.png?12

Go to the 144 Chart-

NOTE the amplification of the jet- a high pressure is sandwiched in there- Look at the jet flow over the top- it doesnt get right out to the top of greenland- subsequently the shortwave that we were watching traversed east across Greenland & then interacted with the trough coming out of svalbard & they both were picked back up South in the jet flow-

Also look at the jet energy cutting across the UK- the shortwaves will sit on the southern Side hence the lightish easterly flow-

http://91.121.94.83/modeles/gfs/archives/gfs-2009120812-0-150.png?12 T150 on this one-

Now we move onto todays model run- the energy distribution has changed- obviously T144 is now T96-

look at the jet now on the GFS_

http://91.121.94.83/modeles/gfs/run/gfs-5-96.png?12

A LOT more amplified in terms of loop over greenland- Now remember if the NET energy off the states is ~ the same as X2 days ago then if theres less pulsing North the rest is going into the Southern arm-

When you energise the southern arm the net in this situation is forcing low pressures NE wards- Because there is blocking out of greenland then there is a greater force & SQUEEZE of the isobars along the boundry- in this case Southern England & Northern France- resulting in this-

http://91.121.94.83/modeles/gfs/run/gfs-0-96.png?12

What this also means though is the shortwave that was orginally going to traverse through Greenland is now pushed more poleward & moves slower & doesnt phase with the Svalbard system- as a consequence its delayed & weaker & further North ...........

The ECM on the other hand has taken a step in the other direction by forcing more energy in the northern arm- it has minimal disruption to our 72 chart ( but enough to cause the flow to be to far South & east for a good Easterly to start with- & because of that faster initial flow any subsequent ridging towards greenland from the Upper high to less pronounced & its final local is somewhat tempered - centred more East & South-

To put this into perspective is a SMALL SMALL pterbation between each model- spin this out to t72 & you get minimal difference- throw it to 96 & theres still the same OVERALL hemisphric pattern as is 120 but there are distortions in the shape of the high when comparing model to model-

out to 144/168 & beyond that intial distortion- maybe a difference of only 10 m/s in each arm is enough to show the Greenland high Sinking on the ECM or the GFS block holding strong with undercutting-

incidentally- we had a poor run from the ECM the other day here VV- notice that the jet flow is strong in the northern arm & not amplified- however as we are very very close on this pattern - this run does appear to be quite wrong, & this arguement lends itself to todays similar arguement that the ECM is progging to much Northern Energy-

http://www.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/deterministic/msl_uv850_z500!Wind%20850%20and%20mslp!144!North%20hemisphere!pop!od!oper!public_plots!2009120712!!chart.gif

We must be cautious though as every time this has happened before the northern arm & the ECM have been correct- HOWEVER the background modality change of the AO & NAO do somewhat mute the previous signals we have seen before & along with it some of the comments put forward by some of our more volatile members-

We have been here before- the GFS looks more believable & this would be a dead cert major easterly if it was yesteryear- but we have to wait as quoted before until the train is visible to confirm its not detouring to Greece or even holland & france in this scenario....

CIAO

Steve

[Iceberg]

I'm afraid Will is very much ramper, if 1 model out of 5 showed cold, he would back that solution.

Very solid support from the ECM ensembles for the operational solution, the 18z could throw anything up but I would expect pretty uniform agreement to the ECM solution on the 0z runs.

Utter rubbish, you don't have access to the EPS Ian. come on stop making it up.

The problem with the Holland EPS results is that Holland has pretty much the same weather under ECM and GFS, so unfortunately they are pretty useless in figuring out how much of an outlier the ECM ops was.

[sebastiaan1973]

hai weatherfanatics, my name is Sebastiaan from the Netherlands

I really like to read your forum, so I joined this forum and this is my first attribution.

I would like to say to you, that a Dutch meteorologist just told at weerwoord.be that the EC of tonight is probably containing a fault.

He wrote

Dit is een grote sprong tussen twee ensembles, vrij ongewoon. Er bestaat kans dat het gehele ensemble, en ook de ECMWF operationele run, beïnvloed is door een relatief grotere fout in de analyse. Zo zie ik dat er geen gegevens van de MTSAT, de geostationaire satelliet voor Oost-Azië, zijn meegenomen. Dat is de afgelopen drie maanden niet eerder gebeurd.

THere is a giant gap between the two ENS, which is very unsual. There is a chance that the whole ENS, and also EC operational run is influenced by a relative bigger mistake in the analyses. E.g. I there are no data of MTSAT used, the sattelite for East Asia, this wasn´t case for 3 months.

Another helpful link is this one

http://www.weerplaza.nl/15daagseverwachting/default_pluim.asp?r=midden

it contains the ENS for several areas in the Netherlands

E.g. given southeast of the Netherlands, see that wonderfull control !

[Snowyowl9]

Thanks Fred :lol:

Netherlands by any chance, the models are really confusing me now, think I will just hope for the best in the morning, if there is 140 online at 7 am it might be good news.

Yes Frosty lets see what the morning brings.

This is when it all starts to collapse on ECM.

http://91.121.93.17/pics/Recm1441.gif

Still a good run for a cold dry spell,but nothing special what we really want to see after all we all want that bitterly cold air for once.

OP`s post is positive I hope your right.

[kold weather]

The 18z GFS is going to be important but even more importantly the 0z runs is going to be far more important then any other of the 18z output I suspect.

FWIW the ECM really is terrible, probably a shot at wintry showers at 144hrs but even then I suspect it'd be mainly of rain....the ECM screams to me temps overnight close to freezing but probably a lot of cloud and temps in the day between 4-6C. Cool but probably not that cold really...milder then the 0z ECM and a lot milder then any other output.

[Neilsouth]

http://www.wzkarten.de/pics/Rtavn001.png

Well it's coming out now ofcause no change YET

[sebastiaan1973]

hai weatherfanatics, my name is Sebastiaan from the Netherlands

I really like to read your forum, so I joined this forum and this is my first attribution.

I would like to say to you, that a Dutch meteorologist just told at weerwoord.be that the EC of tonight is probably containing a fault.

He wrote

Dit is een grote sprong tussen twee ensembles, vrij ongewoon. Er bestaat kans dat het gehele ensemble, en ook de ECMWF operationele run, beïnvloed is door een relatief grotere fout in de analyse. Zo zie ik dat er geen gegevens van de MTSAT, de geostationaire satelliet voor Oost-Azië, zijn meegenomen. Dat is de afgelopen drie maanden niet eerder gebeurd.

THere is a giant gap between the two ENS, which is very unsual. There is a chance that the whole ENS, and also EC operational run is influenced by a relative bigger mistake in the analyses. E.g. I there are no data of MTSAT used, the sattelite for East Asia, this wasn´t case for 3 months.

Another helpful link is this one

http://www.weerplaza.nl/15daagseverwachting/default_pluim.asp?r=midden

it contains the ENS for several areas in the Netherlands

E.g. given southeast of the Netherlands, see that wonderfull control !

[Neilsouth]

TOO ALL THOSE THAT THINK ECM IS RELIABLE AND THE BEST MODEL

http://www.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/deterministic/msl_uv850_z500!Wind%20850%20and%20mslp!168!Europe!pop!od!oper!public_plots!2009120312!!chart.gif

Check how wrong it was for todays forecast , according to ecm we should be under a southwesterly and wet

[Snow Queen one]

hai weatherfanatics, my name is Sebastiaan from the Netherlands

I really like to read your forum, so I joined this forum and this is my first attribution.

I would like to say to you, that a Dutch meteorologist just told at weerwoord.be that the EC of tonight is probably containing a fault.

He wrote

Dit is een grote sprong tussen twee ensembles, vrij ongewoon. Er bestaat kans dat het gehele ensemble, en ook de ECMWF operationele run, beïnvloed is door een relatief grotere fout in de analyse. Zo zie ik dat er geen gegevens van de MTSAT, de geostationaire satelliet voor Oost-Azië, zijn meegenomen. Dat is de afgelopen drie maanden niet eerder gebeurd.

THere is a giant gap between the two ENS, which is very unsual. There is a chance that the whole ENS, and also EC operational run is influenced by a relative bigger mistake in the analyses. E.g. I there are no data of MTSAT used, the sattelite for East Asia, this wasn´t case for 3 months.

Another helpful link is this one

http://www.weerplaza.nl/15daagseverwachting/default_pluim.asp?r=midden

it contains the ENS for several areas in the Netherlands

E.g. given southeast of the Netherlands, see that wonderfull control !

Hi there i would like to say thankyou for your post and i hope that some of the more experienced forcasters on here are able to go to your link to see what you see. It is a relief that there is maybe a problem with the ecm we look forward to you joining our debates and welcome.

[Paul]

Just a quick reminder for those who didn't see it earlier- the latest forecast from Michael Fish is online with his take on the weekend and potential for cold/snow into next week. Unfortunately due to server problems we couldn't show any graphics on the forecast this week but he makes up for that with some interesting thoughts:

http://www.netweathe...chaelfish;sess=

[Thundery wintry showers]

I expected Ian Brown to return on here because the ECMWF 12Z, with its northerly tracking jet pushing the block south, is the first run for a while that has supported his "modern winter" theory. In fact that's one of the first things that went through my head when I saw the run.

However, the last time a run cropped up that was consistent with the modern winter phenomena (I think it was the ECM from 2 or 3 days ago), Ian was pretty sure that all other models would fall into line, and as it happens they didn't.

The modern winter theory does work most of the time these days, but as last winter illustrated, not always. Whether this is one of those exceptions remains to be seen but the AO and NAO do make it more likely than in previous instances. I would also like to mention that today's ECM 12Z is not greatly different from yesterday's 00Z, so it has been spouting similar scenarios for a while, but interspersed with yesterday's 12Z run which showed a bone-chilling north-easterly and a big low in the North Sea.

I am currently very much on the fence on this possible snowy spell- this morning I was swinging towards 70-30 odds on, but after seeing tonight's ECM in particular I have reduced those odds to 50-50. But with the massive uncertainty from one run to the next I don't think we've seen enough to aloow the probability to drop below 50% yet.

[kold weather]

absolutely the ecm was the most consistent from the start so theres no reason to suspect its wrong and it is the top model out of them all,

and most of the more expert people are not giving there thoughts its easy to side with the models that give us what we want.

What a load of tosh Badboy, most consitant, we must have a different defination of the word, the ECM has been on and off the train more times then I've had hot dinners!

The GFS paralell and the UKMO is the one that is really consitant.

You maybe right in respect to the outcome and the ECM is one model you'd rather have on your side then against it but get your facts right please, of course those models could be consistantly wrong, seen that happen many times!

[Geordiesnow]

TOO ALL THOSE THAT THINK ECM IS RELIABLE AND THE BEST MODEL

http://www.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/deterministic/msl_uv850_z500!Wind%20850%20and%20mslp!168!Europe!pop!od!oper!public_plots!2009120312!!chart.gif

Check how wrong it was for todays forecast , according to ecm we should be under a southwesterly and wet

i can only assume looking at the dates that the ecm predicted this outcome for today on the 3rd December, i'm not sure though.

A bit concerning regarding the ecm, it must be said, the GFS is on it's own regarding the first easterly so even this is not nailed on yet sadly.

[Snow Queen one]

hai weatherfanatics, my name is Sebastiaan from the Netherlands

I really like to read your forum, so I joined this forum and this is my first attribution.

I would like to say to you, that a Dutch meteorologist just told at weerwoord.be that the EC of tonight is probably containing a fault.

He wrote

Dit is een grote sprong tussen twee ensembles, vrij ongewoon. Er bestaat kans dat het gehele ensemble, en ook de ECMWF operationele run, beïnvloed is door een relatief grotere fout in de analyse. Zo zie ik dat er geen gegevens van de MTSAT, de geostationaire satelliet voor Oost-Azië, zijn meegenomen. Dat is de afgelopen drie maanden niet eerder gebeurd.

THere is a giant gap between the two ENS, which is very unsual. There is a chance that the whole ENS, and also EC operational run is influenced by a relative bigger mistake in the analyses. E.g. I there are no data of MTSAT used, the sattelite for East Asia, this wasn´t case for 3 months.

Another helpful link is this one

http://www.weerplaza.nl/15daagseverwachting/default_pluim.asp?r=midden

it contains the ENS for several areas in the Netherlands

E.g. given southeast of the Netherlands, see that wonderfull control !

can one of the more experienced mebers look at this link and tell us what they think please i don't read dutch.

[Harsh Climate]

http://www.wetterzentrale.de/pics/Rtavn181.png O dear gfs 18z at 18h is going the way of the ecmwf!! :o :o :o Edited December 10, 2009 by Jed Bickerdike

[Alex95]

http://www.wetterzentrale.de/pics/Rtavn181.png O dear gfs 18z at 18h is going the way of the ecmwf!! :o :o :o

Not really, all the GFS runs lately have gone for that tomorrow. The high pressure will move through the UK and head northwards, its where it ends up, along with the shortwave(s) after the weekend, that's causing the nail biting.