Model Output Discussion - 31/10/2014 and Beyond

[fergieweather]

Maybe the operative word there is 'significant' - one should not expect significant cold in the middle of November but it does not rule out a trend to cold.

Precisely so.

However, cumulative impacts from rain in W/SW is key concern for UKMO into more reliable timeframe.

Edited November 8, 2014 by fergieweather

[Captain Shortwave]

hmm

Certainly holds promise. A long way to go though.

[SMU]

& there be the first twitch with perfect timing..... 2 posts above....

Updated MOGREPs must be seeing the signalled block-

Not much required to get the UK cold but a fair way to go to get very cold-

Edited November 8, 2014 by Steve Murr

[skadi]

With the ECM and UKMO in agreement at day 6, then there is certainly a good chance of a true Scandi high developing into week 2 (as in one supported by low pressure and cold air to the south as opposed to the moment where it is fed by mid-latitude ridging). We do need agreement on the development of heights towards Svalbard which will allow cold air to start feeding into Europe slowly but surely.

The GEM does this a few days later but the damage is done

Good polar heights, bad Atlantic and European pattern with a developing mild southerly.

So need for caution at the moment

To be honest, the GFS isn't far off the Euros on the block. So we have a good start point in my opinion. GFS parallel, not so hot. 

 

What we need imo is what we call in Dutch a "drafter", some LP near Italy (or Genua ) to make this work:

 

[lorenzo]

Love it when these crop up on the anomaly plots, you know something is afoot...! Black Hole watch..

 

[carinthian]

Hi C,

 

It's not been overwhelmingly exciting for cold lovers looking face value at the current/recent NWP output out to T+240. But the upper flow foundations are being laid for something colder later this month and perhaps into December, these foundations certainly are looking solid looking at medium range ensembles.

 

Certainly HP over Scandi in itself isn't going to guarantee cold will come our way with low pressure/upper torugh so close to the UK, but should we see retrogression of the wave pattern, then it may quickly become interesting for cold lovers, i.e. artic cold pool dropping down into NW Russia and then spreading SW as the Scandi retrogresses west. Can't see this happening until later in the month at the earliest though.

Morning Nick,

Good timing, it looks like the ECM and UKMO may be singing on the same hymn sheet for the scenario you have mentioned in your post above. Good call if it comes off and would be a welcomed cold spell later this month. Will be interesting to see further progs later today, especially the UKM0 reading post 144 hours. Whats you view on the latest outputs more widely for Europe generally? Our 10 day snow forecast is due today, hope its better than the last one ! We are due to open 3 weeks today.

C

[Cloud 10]

not really john - want to see the new gefs ens suite running. Have no idea when it will go live but the fact we still don't see it running in parallel leads me to think it won't be this side of the new year.

I wonder if tomorrow's ops will begin to show a complete split to our north in week 2?

 

Didn't have to wait long did we?

 

The usual caveats apply when viewing operational runs at 240 hrs,but nevertheless,cor blimey!

 

 

 

@ lorenzo

Edited November 8, 2014 by Cloud 10

[skadi]

Morning all

The ECM train rolls on this morning now joined by the UKMO at 144-

Huge retrograde block setting up as a strong EAST NAO-

ECM T2M for the uk at day 10 likely to be sub 5c

As much as I loath it because of last year GFS needs to be on board-

Watch for the ECM ensemble T2M crash at day 9 & 10

S

Well here's the ECM ensemble for The Bilt, Netherlands:

 

[TEITS]

Although I haven't posted on this thread for a long time I have been following the model output and I feel the quest for cold/snow is allowing some to miss the bigger picture. I also read a comment saying this is typical November output!!

 

Let me assure you todays ECM especially at +240 is far from the norm for November and is far more likely in late winter/early spring. If the ECM went out further than +240 you can be sure a very cold NE,ly would set in.

 

http://www.wetterzentrale.de/pics/Recmnh2401.gif

 

If you look back at previous significant cold spells you can see the building blocks being put in place some distance away from when the cold actually arrived. I feel the same is happening now with the output and it may take until the last week of November to arrive.

 

Very exciting times ahead!

[knocker]

 

 

Let me assure you todays ECM especially at +240 is far from the norm for November and is far more likely in late winter/early spring. If the ECM went out further than +240 you can be sure a very cold NE,ly would set in.

 

 

You can't actually. The ECM goes out to T360 and it doesn't. Basically it keeps low pressure central Atlantic and at T360 has a light northerly with average temps.

[captaincroc]

Although I haven't posted on this thread for a long time I have been following the model output and I feel the quest for cold/snow is allowing some to miss the bigger picture. I also read a comment saying this is typical November output!!

 

Let me assure you todays ECM especially at +240 is far from the norm for November and is far more likely in late winter/early spring. If the ECM went out further than +240 you can be sure a very cold NE,ly would set in.

 

http://www.wetterzentrale.de/pics/Recmnh2401.gif

 

If you look back at previous significant cold spells you can see the building blocks being put in place some distance away from when the cold actually arrived. I feel the same is happening now with the output and it may take until the last week of November to arrive.

 

Very exciting times ahead!

 

Exactly! Yes, if we look out the window it is 'normal' November weather (Wet n Windy), but the charts are far from that.  The Black holes on the anomaly charts back that up! (Off the scale/chart!)

 

Exciting times for sure.

[Purga]

OK happy rampers, there we go

But - here is a Nov 1997 chart showing Nblocking, split vortex etc & lots of 'potential'

and 1998 turned out to be hopelessly mild.

 

So... nice charts to be sure and good possibilities but anything can happen in our wonderfully chaotic atmosphere & that's what makes it all so fascinating to try and predict.

 

I really hope for a great cold spell to evolve this season, we all deserve it after last year!

Edited November 8, 2014 by Purga

[bluearmy]

You can't actually. The ECM goes out to T360 and it doesn't. Basically it keeps low pressure central Atlantic and at T360 has a light northerly with average temps.

Dave is talking about the op ECM knocks. The control retrogresses the block to the nw and allows a euro train of depressions swinging sw to ne . No frigid cold for us but certainly a chance of some snowfall from that control run.

Going back to the ECM ens, the mean does plant a mean trough in the mid Atlantic at 528dam. at two weeks out, that's pretty low for the time of year at that latitude. Depending on the behaviour of the blocking to our north, that's a source of a lot of energy for Europe. the blocking will dictate where it impacts.

[snowsummer]

Sorry. Meant chart not map! Excitement got the better of me in my eagerness to learn!

[knocker]

Going back to the ECM ens, the mean does plant a mean trough in the mid Atlantic at 528dam. at two weeks out, that's pretty low for the time of year at that latitude. Depending on the behaviour of the blocking to our north, that's a source of a lot of energy for Europe. the blocking will dictate where it impacts.

 

Yes that's true blue but at the same time NOAA and GEFS don't make as much of this confining the trough to the SW of Greenland. The ECM seems to have retrogressed the warm air to Greenland and at the same time introducing cold air from the vortex to parts east of Scandinavia. I can feel the pulses racing.

Edited November 8, 2014 by knocker

[mcweather]

In light of Ian F posting last night that the meto see nothing cold from any output  out to 15 days, it is always refreshing to see the one of the models they use turn round and bite them on the bum. lol

 

However we have seen the ECM do this at 240 before only for it to go up in smoke, if the same chart or one very like it comes within 7 days then we might be talking.

 

Having said that, the background signals are far more conducive to such a chart than they were last winter so the ECM may be on to something.

 

The strat thread is proving a seriously fascinating read with black holes now appearing on the anomaly charts over the arctic regions.

 

Good to see TEITS posting again too.

Edited November 8, 2014 by mcweather

[Snowy L]

Sorry if its an obvious question but what exactly does the "black hole" on the map mean please? Ive been trying to self teach (!) On here for the last year but I dont recall ever seeing a chart like this before. Thanks in advance and thanks for a fascinating forum

 

Basically the positive pressure anomaly is so high that it's off the scale.

[bluearmy]

The point here, is that if the ECM op is in the right ballpark by splitting the heights completely, most bets will be off and the highly amplified runs will begin to 'snowball'. (pun completely intended). A cold shot is feasible within two weeks but any deep cold is a fortnight away at the earliest. similarly, many other options remain on the table including the status quo of sceuro block and Atlantic trough.

Sorry to be a pedant snowy, but it's the height anomaly, not pressure.

Edited November 8, 2014 by bluearmy

[BLAST FROM THE PAST]

Sorry. Meant chart not map! Excitement got the better of me in my eagerness to learn!

Anomaly is off the scale,

BFTP

[BLAST FROM THE PAST]

& there be the first twitch with perfect timing..... 2 posts above....

Updated MOGREPs must be seeing the signalled block-

Not much required to get the UK cold but a fair way to go to get very cold-

Bit slow if its only seeing it now?

BFTP

[ITSY]

ECM ens have the op fairly well centred but goes cold at the end. Crucially the control stays with it and stays fairly cold. A few other supporters but no major cluster yet. Still early days - GFS still not on board wth ECM either. Attempt at a variation on a theme though...

[terrier]

Looks to me like the ECM is a massive outliner. It's certainly not backed by its ensembles.

[Nick L]

Looks to me like the ECM is a massive outliner. It's certainly not backed by its ensembles.

 

Really? I'm looking at the UK ensemble graph for the ECM and I'd say the op is pretty much in line.

[BLAST FROM THE PAST]

Looks to me like the ECM is a massive outliner. It's certainly not backed by its ensembles.

What on earth are you talking about? Red is the op run which is the chart run we see, only starts to deviate slightly after 16th, and is not an outlier. The blue is the control run, and only deviates more than op after the 16th. You are misleading folk here....and badly too

BFTP

Edited November 8, 2014 by BLAST FROM THE PAST

[bluearmy]

the ecm control is the T2m outlier.