Model Output Discussion 29th December - Into mid-Winter.

[JBMWeatherForever]

Lots of excitement on here tonight and with good reason. Some saying that the end result might be a half way house between what the ECM and GFS show - But the ECM is still continuing to trend further towards an exciting outlook and the GFS now starting to following it lead.

If as has been said, things are looking like a repeat of March 2013, then that pattern being repeated so much earlier could mean things get serious. We are currently less than a week after the date when the winter of 1947 first took hold.   

[feb1991blizzard]

Just now, Steve Murr said:

Last one from me tonight-

big swing from my ol favourite the NAVGEM 18z

from this 

to the undercutter

S

A lot of the GEFS members look like good undercutters early on like that, the only thing is a lot flattern out, I'm more inclined to believe we may finally get blocking than I have done at any stage recently but feel it will take a few attempts and be after mid feb.

[Guest]

MONITORING SHORT TERM DEVELOPMENTS:

Those of you who read my long post (on page 297 on Sunday evening) will know that I started off looking at the current synoptic patterns and I focused on the strength and extent of the European cold block and the strong chances (IMHO) of it hanging on for longer. I felt that we would again draw in more of the "euro-cold" and this would help to fend off the Atlantic for at least a few more days. Well, not only is this now happening (with a very cold day for most of the UK on Thursday predicted) but I believe that there is evidence that things might get even more interesting during the next few days - this is before we get to the possible ECM 12z evolution for next week. I'll demonstrate my point with charts as I go along.

Firstly, the 12z Met office Fax Charts for the next 48 hours. These show the HP to our east ridging to a new HP developing over Finland. This is predicted to move east and then south, merging with the cell of central Europe and topping up the cold to the east.

             T+6  1800 Tuesday                             T+24 1200 Wednesday 1200                     T+36 0000 Thursday                           T+48 1200 Thursday

   

Now let's follow exactly what is happening. The "live pressure chart below should (hopefully) update at regular intervals. The link to the right takes you to the chart where you can use the new Meteoceil animations. Just click on "Animation on 24" above the chart and you can see the changes during the last 24 hours. The HP centred over Germany is remaining more or less in situ and is building slowly. The ridge over Finland is forming and building too but is not slipping eastwards (at least as at 2300). Now anomalous and long lasting HPs like this one are notoriously difficult to forecast accurately in terms of movement, central pressure and building/ridging/retrogressing/ linking to new cells etc. I think that there is a reasonable chance that the HP will re-align itself rather closer to us than shown on the Wed/Thur fax charts. There may be an even greater squeeze developing and the south-south-easterly on Thursday may well last for several days at least. This will keep any milder air even further to our west. This is only part of my point.   

Live Pressure Chart (1mb gradients)

   and the link to the site for animations:    http://www.meteociel.fr/observations-meteo/pression.php?region=eur2 

Next the satellite images. The cloud associated with the warm front (see the first fax chart above) has dissolved far more quickly than expected during Tuesday evening.

    Satellite Imagery - Tuesday 1300                               Satellite Imagery - Tuesday 1900                            Satellite Imagery - Wednesday 0100                                    "Live" Satellite Imagery

                                                                        

Here is the link to archive satellite charts. You can change the date and bring up any previous 6 hour period. Click on "animations" on the left side to bring it to life (there is about a 10 second delay):   http://www.meteociel.fr/observations-meteo/satellite.php?mode=archives-infrarouge-noir-et-blanc  

Finally, the extent and depth of the cold. Last night's minimums, today's maximums and the current charts (links below each chart). Even allowing for the large diurnal ranges for the min/max temps, the cold is slowly deepening again and becoming generally more extensive.

The less cold wedge in northern Europe up to the south Baltic Sea is being squeezed out by renewed cold from the north, the north-east and over central Europe.

                Tue/Wed min temps                                         Wed max temps                                     Current temps - NW Europe (live chart)                                      Current temps - All Europe (live chart)                    

                                                                        

                                                                                                                                   http://www.meteociel.fr/observations-meteo/temperatures.php   http://www.meteociel.fr/observations-meteo/temperatures.php?region=eur2 

Okay, this may all have changed by Wednesday morning or later in the week. I do feel that there is still a lot of life in the Euro cold block. Is it possible that a proper cold spell could actually develop out of this. Might the HP take up a more northerly position, like over Scandinavia? The evolution that most of us are chasing might already be underway? I can see myself eating a large slice of humble pie over this one. Best to sit back and await short term developments.

 

Edited January 25, 2017 by Guest
Correcting typos and to ensure that all the links and charts work properly.

[Pembroke Dangler]

28 minutes ago, Bring Back1962-63 said:

MONITORING SHORT TERM DEVELOPMENTS:

Those of you who read my long post (on page 297 on Sunday evening) will know that I started off looking at the current synoptic patterns and I focused on the strength and extent of the European cold block and the strong chances (IMHO) of it hanging on for longer. I felt that we would again draw in more of the "euro-cold" and this would help to fend off the Atlantic for at least a few more days. Well, not only is this now happening (with a very cold day for most of the UK on Thursday predicted) but I believe that there is evidence that things might get even more interesting during the next few days - this is before we get to the possible ECM 12z evolution for next week. I'll demonstrate my point with charts as I go along.

Firstly, the 12z Met office Fax Charts for the next 48 hours. These show the HP to our east ridging to a new HP developing over Finland. This is predicted to move east and then south, merging with the cell of central Europe and topping up the cold to the east.

             T+6  1800 Tuesday                             T+24 1200 Wednesday 1200                     T+36 0000 Thursday                           T+48 1200 Thursday

   

Now let's follow exactly what is happening. The "live pressure chart below should (hopefully) update at regular intervals. The link to the right takes you to the chart where you can use the new Meteoceil animations. Just click on "Animation on 24" above the chart and you can see the changes during the last 24 hours. The HP centred over Germany is remaining more or less in situ and is building slowly. The ridge over Finland is forming and building too but is not slipping eastwards (at least as at 2300). Now anomalous and long lasting HPs like this one are notoriously difficult to forecast accurately in terms of movement, central pressure and building/ridging/retrogressing/ linking to new cells etc. I think that there is a reasonable chance that the HP will re-align itself rather closer to us than shown on the Wed/Thur fax charts. There may be an even greater squeeze developing and the south-south-easterly on Thursday may well last for several days at least. This will keep any milder air even further to our west. This is only part of my point.   

Live Pressure Chart (1mb gradients)

   and the link to the site for animations:    http://www.meteociel.fr/observations-meteo/pression.php?region=eur2 

Next the "live satellite image. The cloud associated with the warm front has dissolved far more quickly than expected this evening. Again, the link to the chart with earlier animation available, especially if you look at this on Wednesday morning.

Live Satellite Imagary

  and the link to the site for animations:    http://www.meteociel.fr/observations-meteo/satellite.php

Finally, the extent and depth of the cold. Last night's minimums, today's maximums and the current charts (links below each chart). Even allowing for the large diurnal ranges for the min/max temps, the cold is slowly deepening again and becoming generally more extensive.

The less cold wedge in northern Europe up to the south Baltic Sea is be squeezed out by renewed cold from the north, the north-east and over central Europe.

                Tue/Wed min temps                                         Wed max temps                                     Current temps - NW Europe (live chart)                                      Current temps - All Europe (live chart)                    

                                                                        

                                                                                                                                   http://www.meteociel.fr/observations-meteo/temperatures.php   http://www.meteociel.fr/observations-meteo/temperatures.php?region=eur2 

Okay, this may all have changed by Wednesday morning or later in the week. I do feel that there is still a lot of life in the Euro cold block. Is it possible that a proper cold spell could actually develop out of this. Might the HP take up a more northerly position, like over Scandinavia? The evolution that most of us are chasing might already be underway? I can see myself eating a large slice of humble pie over this one. Best to sit back and await short term developments.

 

I love this post simply because if the models start with wrong info then how can they be right in 6, 12, 18, 24 hrs .. and so on. It's such a conundrum when there is high pressure to our east and north models just can't get a handle on it unless its a zonal Atlantic train. Just subtle changes in an hour from now could put the whole days model suites completely out. And the post by Bring Back 1962-63 just goes to show exactly that imo. Great post 

[That ECM]

Ukmo at t144 and the gfs perbs and t144. I would suggest more edging towards ukmo. Still need it to improve. Let's hope the ecm can improve again and lead the way. 

Edited January 25, 2017 by That ECM

[mb018538]

Looks pretty poor all round this morning so far....maybe people are getting themselves all lathered up for nothing?? Can't see anything great coming from that UKMO run, and the less said about the GFS the better. Zonal zonal zonal.

[shane303]

The charts are all over the place at the moment with the block still holding on in the south and east with a very cold day to come on Thursday nothing is set in stone so don't take this mornings run to heart and we haven't even had the ecm yet . 

Edited January 25, 2017 by shane303

[KTtom]

13 minutes ago, shane303 said:

The charts are all over the place at the moment with the block still holding on in the south and east with a very cold day to come on Thursday nothing is set in stone so don't take this mornings run to heart and we haven't even had the ecm yet . 

Unfortunately  it's looking like it's going the way of the UKMO...heights over Iceland lower with the southwesterly flow taking over at t96.

 

We're used to ECM being poor at day 10, but the gremlins seem to be taking over within t120 Now! 

 

 

Edited January 25, 2017 by KTtom

[booferking]

Uk model looks poor gfs looks poor ecm takes a massive move to both even at 72hr and 120hr chance is missed garden path again lads you can all come back down again.. 

I can still see a few strays wondering on the path.

Edited January 25, 2017 by booferking

[That ECM]

Shame, oh well. Half way house was never going to cut it and always looked the favourite. 

[Ali1977]

Not a great night of charts, I think when charts are all over the place it's good just to stick with the METO long range which doesn't mention anything cold or very cold just yet. Not sure about anyone else but I'm ready to get rid of this inbetween type weather and get some Zonal for a while as thenwe may have chance of something different!! 

[Seasonality]

Last time I checked one set of runs is not definitive. Why the smug schadenfreude and wrist slashing? None of the models have been covering themselves in glory lately.

Edited January 25, 2017 by Seasonality

[shane303]

Everything will change again by this evening I can't see the block giving away that easy after such a fight , stop thinking winter is over by one set of morning runs. 

[mb018538]

I don't think anyone is saying winter is over! A few maybe got drawn in, but that's standard winter model watching!

[Seasonality]

4 minutes ago, shane303 said:

Everything will change again by this evening I can't see the block giving away that easy after such a fight , stop thinking winter is over by one set of morning runs. 

Wait for it shane. Soon the old wives tales and other baseless myths will come out. Like "once the models flip they never flip back" and other such sound scientific reasoning. Sarcasm intended. 

[mulzy]

Even at day 9 on the ECM, the Atlantic is not winning.  Looks blocked to me.

[jvenge]

Expectations :-) yesterday 0z was different to the 12, even in the near term, which is a big clue as to what the next 0 can do. 

In actual fact, though, the changes are very small and in the near term. Quite amazing to see how those little things can give such different outcomes. 

[terrier]

So after all the bashing the gfs was getting last night it seems like it is calling it correct again. All the talk was last night of the mighty ecm been right and was going to be the only model that everything would move towards. Well the ecm has moved towards the ukmo and gfs even as early as t72hrs so I think it's  back to the drawing board again. Story of our winter really. 

[TEITS]

2 minutes ago, terrier said:

So after all the bashing the gfs was getting last night it seems like it is calling it correct again. All the talk was last night of the mighty ecm been right and was going to be the only model that everything would move towards. Well the ecm has moved towards the ukmo and gfs even as early as t72hrs so I think it's  back to the drawing board again. Story of our winter really. 

Considering the vast changes in the models, isn't it a bit daft to be calling a model correct at this stage?

[mb018538]

3 minutes ago, mulzy said:

Even at day 9 on the ECM, the Atlantic is not winning.  Looks blocked to me.

Erm, are we looking at the same charts here?? Looks pretty Atlantic dominated to me!





Ensembles also have no cold members, and plenty of ppn throughout. Unsettled.

[northwestsnow]

Just now, TEITS said:

Considering the vast changes in the models, isn't it a bit daft to be calling a model correct at this stage?

Kind of but the changein the ECM overnight is stark.Chalk and cheese spring to mind.

That said its fascinating model watching-surelythe strat warming will bring some better fortunes down the line..

[bluearmy]

With so many clusters evident early on in the ens suites, it's never going to be a straightforward route to anywhere.

very difficult to make judgements when patterns are changing within 4/5 days!

less energy going se on today's ops early on but no one knows if that will change by the 12z's!

[Kentish Snowman in Yorks]

2 minutes ago, mb018538 said:

Erm, are we looking at the same charts here?? Looks pretty Atlantic dominated to me!





Ensembles also have no cold members, and plenty of ppn throughout. Unsettled.

Does it?!   The centre of the low pressure is still West of Ireland and there is still a ruddy great high pressure over Europe keeping them cold and blocked!

Bit like now really so no not Atlantic dominated in my book.....

[That ECM]

15 minutes ago, shane303 said:

Everything will change again by this evening I can't see the block giving away that easy after such a fight , stop thinking winter is over by one set of morning runs. 

The block is still there it just doesn't go where most of us would like. The interest comes when ecm decides to move it further north than the gfs. The gfs edges towards ecm for 24/48 hours and then the ecm moves towards the gfs as we get nearer to t0. Unfortunately all winter a halfway solution hasn't delivered the goods. 

 

Never seen the point of slating one model over the other. Take all info and "guess" from there. 

[Gowon]

3 minutes ago, TEITS said:

Considering the vast changes in the models, isn't it a bit daft to be calling a model correct at this stage?

Very true but SM did say the ECM was correct last night and it's now reverted back.