Model Output Discussion - 18z - 25th Nov onward

[AutumnMists]

Everyone has there own thoughts on the model output this afternoon and evening all with different thoughts. I think if we see a cold trend lots of people always say the trend is there and always try and discount the mobile/milder conditions.

However the trend is there for milder and really not that cold conditions yes it may get chilly between the 2nd -6th with snow over high ground in the north but i think we are clutching at straws. Before anyone asks I am looking at all models and output, I do like colder weather and no im not trying to upset anyone.

Im trying to be honest lets recognise the trend for less cold contiditions....I have said trend and not any specifics I hope im wrong!

You're not the only one that is a bit miffed about next week!

The general scenario I think the models (despite their ever increasing conflicting signals) is for a cold snap this weekend with some possible notable falls the further North and East you go (away from these areas, the higher up you go) ...

Some decent agreement for a breakdown of the cold from the 3/4th onwards.

Looking even further ahead and just picking out the best bits, a ever so slight touch of a cold resurgence - perhaps - later on next week ... although this is extremely far away and could turn out to be a non event.

Speaking of non events, as some users have pointed out, I feel for the Irish.

[Isolated Frost]

FAX at 72hrs holding it steady- a small upgrade even of the dm line since yesterday's 12z- t48 also was an upgrade- the vital t96 and t120 come tonight about 1030- after the MO boffins meet up- important run wrt the true trough movement whether it's c europe/scandi- and progression of the nova scotia low

[The PIT]

Well we move onto a different version of events but still mostly on the cool > cold side. Hopefully this sceniro won't be downgraded before it moves into the reliable time frame.

[nick sussex]

To be fair Nick, the ECM has been VERY consistent with sending the trough into Scandinavia hence why the ECM has been predicting a Northerly flow instead of an Easterly flow as per the UKMO. The UKMO consistency of keeping the trough where it is means the UKMO has been consistently projecting our winds will come more from the East instead of the North. So at the moment, its like a game of chess where it looks like its heading into a stalemate which neither backing down but obviously one is going to have two. If you base it on the overall consistency, you would favor the UKMO but it does not always work out that way, one minor change from the UKMO regarding the trough will change things.

The GFS has toyed with both ideas but tonights 12Z is favoring more of the UKMO's idea with the trough, unfortunately it favors the Atlantic making a breakthrough hence why we see any easterly flow hitting Holland instead of the UK.

Its going to be REALLY interesting which model has got it right regarding the trough over Europe!

I take your points but the ECM has been dismal over the last few days, indeed only yesterday it pushed all the energy eastwards and didn't even develop the Canadian low.

Of course it generally comes out on top in terms of verification but its not without its occasional implosions.

I expect we might see some middle ground solution but I don't buy the Mr Blobby trough, and if thats wrong then like dominoes the rest of its output falls.

Edited November 26, 2012 by nick sussex

[John Cox]

Our Met office here in Ireland use the ECMF as far as i know and this is part of their forecast this morning "There is a gradual return to milder weather next weekend as temperatures climb towards more normal values of 9 or 10 degrees."

I find our met guys are rarely wrong so, although I wish it was otherwise, I'm afraid a breakdown of the cold spell looks on for the weekend and after that does not look great from their charts.

Hope they and I are wrong.

So the ECMF isn't budging tonight in the area that this model excels in, and very bullish with it - I'd think very hard before binning it!

Obviously weather preferences will determine which model you follow regardless of any stats.... Somethings gotta give sooner or later folks! Heart says UKMO head says ECM....

[Dampdorset82]

You're not the only one that is a bit miffed about next week!

The general scenario I think the models (despite their ever increasing conflicting signals) is for a cold snap this weekend with some possible notable falls the further North and East you go (away from these areas, the higher up you go) ...

Some decent agreement for a breakdown of the cold from the 3/4th onwards.

Looking even further ahead and just picking out the best bits, a ever so slight touch of a cold resurgence - perhaps - later on next week ... although this is extremely far away and could turn out to be a non event.

Speaking of non events, as some users have pointed out, I feel for the Irish.

I agree, This time last week there were hints of slightly milder coming in and lots of people said its just the models cant handle it it will upgrade, now we have compltely flipped we are now looking at only hints of cold weather .

[Mark Bayley]

Another nail biting day, although there does seem to have been a general move towards the UKMO, containing the best output for those wanting a more sustained and potentially snowy spell (short to medium term).

Whatever happens, and despite what the models show, i feel any milder spell would be rather brief, as echoed by many of the resident experts. There is no support for a strong polar vortex, and a +AO, especially when viewing the latest stratospheric output. The recent geopotential height charts show a rather weak and fragmented PV, and unless i'm interpreting it wrong, there is a trend to send a fragment into Europe. This would support height rises around Greenland, which is supported by the latest MJO output, and NAEFS ensemble mean.

NAEFS ensemble mean, shows strong support higher pressure in the mid atlantic and Greenland area

The general trend is to send the MJO into phase one, as shown by GFS, UKMO and ECM.

This would give us the following composite. Note Greenland heights, and the trough over us. Although maybe not ideal for the south, it should be noted that these composites are of use as a guide.

Into and through December i see support for continued blocking, with some support for blocking around Greenland. The outlook to me, over the next few weeks, is a positive one if your seeking cold!

Edited November 26, 2012 by Mark Bayley

[Frosty.]

Good ECM op tonight - its out in FI anyway, but only a single day of average temps as the low fires through, and then back to cold by day 9. Ensembles likely to do the same. Looks like GP's assessment was spot on (again).

It's a big improvement on last night, but especially for the northern ¼ of the uk, a slightly milder or less cold blip further south but no sign of returning to raging mild zoneality whatsover.

[West Sussex Kate]

It's a big improvement on last night, but especially for the northern ¼ of the uk, a slightly milder or less cold blip further south but no sign of returning to raging mild zoneality whatsover.

Yes It's looking like an interesting December!

[musicman2000]

Our Met office here in Ireland use the ECMF as far as i know and this is part of their forecast this morning "There is a gradual return to milder weather next weekend as temperatures climb towards more normal values of 9 or 10 degrees."

I find our met guys are rarely wrong so, although I wish it was otherwise, I'm afraid a breakdown of the cold spell looks on for the weekend and after that does not look great from their charts.

Hope they and I are wrong.

John they do use the ecm, as well as the hirlam model, They only showed as far as Saturday after that who knows.

[Geordiesnow]

FAX at 72hrs holding it steady- a small upgrade even of the dm line since yesterday's 12z- t48 also was an upgrade- the vital t96 and t120 come tonight about 1030- after the MO boffins meet up- important run wrt the true trough movement whether it's c europe/scandi- and progression of the nova scotia low

The fax chart looks like the UKMO 72 hour chart too me, but I won't be too surprised if the FAX charts will turn out to be like the UKMO charts though.

Bear in mind, even at 72 hours the models disagree with the trough so when looking at tonights GFS18Z run, look at where the trough will be as we go through the run. If the UKMO charts are right, we could be looking at wintry showers at lower levels for some eastern areas as near as Friday night!

Tomorrow mornings runs will only decide what may happen if the ECM/UKMO FINALLY agree on what they want to do with the trough in Europe because as of yet, they have disagreed on every run hence one shows a more Northerly flow and the other an Easterly flow!

[John Cox]

John they do use the ecm, as well as the hirlam model, They only showed as far as Saturday after that who knows.

Thanks musicman2000 for that additional info. Fingers crossed a reload of cold but the latest ECM is not encouraging at the moment after Saturday

[liam300]

Its seems every day we are flipping backwards and forwards through models, which is really playing with out emotions

[Frosty.]

Yes It's looking like an interesting December!

Yes it is, it has potential to become even colder and more blocked, the meto are still indicating fairly frequent Northerlies which implies a mid atlantic high formation, nice height rises around greenland and a persistent scandi trough..bring it on.

[IDO]

MattHugo81

The UKMO model while consistent has little or no support from the ECMWF ensembles. The Atlantic is likely to 'sneak in' next wkend(or so)...

26/11/2012 19:18

It looks like a matter of time before the UKMO backtracks if the GFS and ECMWF ensembles are worth their salt:

http://cdn.nwstatic..../t850London.png

But GFS/ECMWF models appear to keep a cool/cold outlook form T168. But sustained cold not now looking the synoptic pattern for December. We shall see...

Edited November 26, 2012 by i'm dreaming of...

[SnowObsessor90]

MattHugo81

The UKMO model while consistent has little or no support from the ECMWF ensembles. The Atlantic is likely to 'sneak in' next wkend(or so)...

26/11/2012 19:18

It looks like a matter of time before the UKMO backtracks if the GFS and ECMWF ensembles are worth their salt:

http://cdn.nwstatic..../t850London.png

But GFS/ECMWF models appear to keep a cool/cold outlook form T168. But sustained cold not now looking the synoptic pattern for December. We shall see...

And the ECM32 dayer hasn't even updated yet. Could that be the final kick in the gut? You honestly wouldn't bet against it.

Edited November 26, 2012 by Anonymous21

[nick sussex]

MattHugo81

The UKMO model while consistent has little or no support from the ECMWF ensembles. The Atlantic is likely to 'sneak in' next wkend(or so)...

26/11/2012 19:18

It looks like a matter of time before the UKMO backtracks if the GFS and ECMWF ensembles are worth their salt:

http://cdn.nwstatic..../t850London.png

But GFS/ECMWF models appear to keep a cool/cold outlook form T168. But sustained cold not now looking the synoptic pattern for December. We shall see...

Thanks for posting that. I think we all agree that the Atlantic will try and move in by 144hrs, its not if but how.

Also ensembles are misleading in these situations as they try and take the energy over the top rather than se. I think the JMA would be more inline with how this would happen and the ECM would have been very similar without the bloated trough.

[london-snow]

Our Met office here in Ireland use the ECMF as far as i know and this is part of their forecast this morning "There is a gradual return to milder weather next weekend as temperatures climb towards more normal values of 9 or 10 degrees."

I find our met guys are rarely wrong so, although I wish it was otherwise, I'm afraid a breakdown of the cold spell looks on for the weekend and after that does not look great from their charts.

Hope they and I are wrong.

This maybe the case for western areas and Ireland however for the east, north east, and south east, A battleground type situation seems the form horse to me. These situations have the potential to bring very large snow events to where ever the battle takes place usually the further east the better.

To add i am not disappointed at all with the evening runs still things are very much unresolved and in the balance. If we do see a breakthrough from the atlantic do not be to downbeat as it is very likely that the cold will return before you know it.

[cold snap]

Just been speaking to matt Hugo via my twitter (@markydub)

Says ukmo is on its own and unlikely to verify

Edited November 26, 2012 by Rybris Ponce
'w' inserted...

[Geordiesnow]

MattHugo81

The UKMO model while consistent has little or no support from the ECMWF ensembles. The Atlantic is likely to 'sneak in' next wkend(or so)...

26/11/2012 19:18

It looks like a matter of time before the UKMO backtracks if the GFS and ECMWF ensembles are worth their salt:

http://cdn.nwstatic..../t850London.png

But GFS/ECMWF models appear to keep a cool/cold outlook form T168. But sustained cold not now looking the synoptic pattern for December. We shall see...

To be fair, I think the ECM is more likely to be correct regarding the trough unfortunately because it does appear to have more support from the ensembles and at times the GFS alike but I expected the UKMO to back down by now and it has not, of course it always could on the next run which means any consistency is nothing! As it happens though, the UKMO has more support from other models regarding the trough.

The signs of blocking does not look like disapearing but using Nick's "jam" reference, why have it later when we could have it much sooner. I also think if the ECM is right its a case of all that hoping and looking at the models would be a bit of a waste because any snow would be fairly limited and we have to do it all over again so to speak.

[london-snow]

This maybe the case for western areas and Ireland however for the east, north east, and south east, A battleground type situation seems the form horse to me. These situations have the potential to bring very large snow events to where ever the battle takes place usually the further east the better its also the case whether the cold air will stay in place or not.

To add i am not disappointed at all with the evening runs still things are very much unresolved and in the balance. If we do see a breakthrough from the atlantic do not be to downbeat as it is very likely that the cold will return before you know it.

[Frosty.]

MattHugo81

The UKMO model while consistent has little or no support from the ECMWF ensembles. The Atlantic is likely to 'sneak in' next wkend(or so)...

26/11/2012 19:18

It looks like a matter of time before the UKMO backtracks if the GFS and ECMWF ensembles are worth their salt:

http://cdn.nwstatic..../t850London.png

But GFS/ECMWF models appear to keep a cool/cold outlook form T168. But sustained cold not now looking the synoptic pattern for December. We shall see...

i will believe it's going to be a cold december until the meto decide otherwise, I don't believe we will end up with a full blown zonal set up as the 6z showed. And GP's latest thoughts would be welcomed now

Edited November 26, 2012 by Frosty039

[ChartViewer]

I must say from an objective view

1. I am seeing some of the best synoptics ive seen viewing the models for 6 years

2. An arctic high at 1050...Unbelieveably rare and could be extinct soon!

3. Greenland High/Svalbard blocking linkages...unusual

4. Azores High, GH, linkage again not used to seeing this

5. Split vortex.....amazing after 90's winters and early naughties which had huge vortex and zonal/Bartletts.

6. November 26th and playing with above synoptics is quite strange.........so....

a. GP, Chio, JH, SM etc well done for spotting this synoptic pattern 3 weeks ago

b. Doesnt matter if a slight strengthend northerm arm gets a low through for a couple days mobility the trend is northern blocking....just look at charts posted from all the experts

c. I suspect December 2012 will be cold snowy and very interesting

d. No azores high, bartlett will be seen this side of the New Year:-) giving us Zonal or Mild temps

Enjoy the rollercoaster of the Model thread....those whove been here since 2005 remember the failed Easterly:-)

Edited November 26, 2012 by ChartViewer

[UV-RAY]

And the ECM32 dayer hasn't even updated yet. Could that be the final kick in the gut? You honestly wouldn't bet against against it.

Lets hope they are wrong or we could be looking at average conditions for the time of the year at best. Still that's an improvement on this time last year.

[AWD]

Just to add; (From Matt Hugo)

what about the ECM 32 dayer?†That'll be updated overnight but last Thu update showed further potential blocking mid Dec onwards

So there is continuing support for round two if indeed this weekend fails to take off. First half of December still looking good to come in below average IMO.

Edited November 26, 2012 by AWD