The hunt for cold - Model discussion (late November)

[Summer Sun]

12 minutes ago, Mike Poole said:

I don't rate the JMA for cold potential either, looks broadly in the FV3 ECM camp.  Really need to wait for the situation at T120 to be resolved as it will have a massive impact down the line.  UKMO promising, and you always like to have it on board, but it stops at T144 so we can't be sure of the evolution thereafter.  

Most definitely a case of more runs needed.  

 

UKMO extended has just updated not much difference for the UK but the low is a lot deeper in the Atlantic compared with the 00z

Edited November 20, 2018 by Summer Sun

[A.J]

27 minutes ago, lassie23 said:

Whichever model shows cold and snow seems to be the best performing model in this thread.

^^ the post which has the best chance of verifying

talk about confusing , this thread suffers from bi-polar disorder........navgem's the worst!.......no wait, it's the best!......no wait, has the worst verification stats!.......on the other hand, it has the best..........now, it shows mild, it's crap but hang on T850's are upgrading, the navgem is once again the 'korean meatballs' of models!!......Jeez, this thread has more plot twists than oscar winning 'whodunnit!'....Scooby Doo's got more of a clue!......lol

[Day 10]

Very happy at 120, it wouldn't surprise me if we get one of those stellar runs from the 18z GFS in a bit.

[Geordiesnow]

Just now, Summer Sun said:

UKMO extended has just updated not much difference for the UK but the low is a lot deeper in the Atlantic compared with the 00z

The rounded low has indeed remained large on the UKMO and has now developed a secondary low, you would suspect it would follow the ECM basing on that chart but probably too hard to tell from that chart. 

[Stuie]

1 minute ago, Day 10 said:

Very happy at 120, it wouldn't surprise me if we get one of those stellar runs from the 18z GFS in a bit.

Good post, that Atlantic LP is doing a serious Brexit west from the UK. Wasn`t this supposed to slide SE into Iberia? doesn`t look like it from those charts.

[Froze were the Days]

2 minutes ago, Geordiesnow said:

The rounded low has indeed remained large on the UKMO and has now developed a secondary low, you would suspect it would follow the ECM basing on that chart but probably too hard to tell from that chart. 

Correct with the secondary low...that's what a few models predicted yesterday, no sliding potential with that!

[BLAST FROM THE PAST]

7 minutes ago, Summer Sun said:

UKMO extended has just updated not much difference for the UK but the low is a lot deeper in the Atlantic compared with the 00z

Important to look at how the LP is developing, the deep section is in southerly flank and well south too...that isn’t going to punch through.    

BFTP

[Chesil View]

From what I can see after the 12z today is that in the short term the ECM has taken small steps towards the UKMO/GFS colder scenarios

all it needs to do is keep going bit by bit. Will be interesting to the 0z and 12z ecm tomorrow

Edited November 20, 2018 by Broadmayne blizzard

[ItNeverSnowsInWindsor]

The dreaded Iberian ridge rears it’s ugly head yet again on the ECM 12z...

Hope it’s underplaying the cold pool to the NE’!

Edited November 20, 2018 by prolongedSnowLover

[Decemberof2010]

Does anyone know what time the CMA and NASA models come out??

[MattStoke]

1 hour ago, Mokidugway said:

Why do people resort to the japanese  model in desperation 

Supposedly the Met Office do look at the JMA output. That’s been said on here in the past anyway. Even though it’s not one of the main models for our part of the globe.

Edited November 20, 2018 by Paul

[pdiddy]

12 minutes ago, phil nw. said:

Let's keep it sensible-and friendly please folks.

There's humour and there's unpleasantness and we don't want the latter ta.

Now back to the cold hunt,preferably with some model content.

Cold Hunt sounds like a spoonerism from Donald Trump... Moving swiftly on, so much uncertainty on the lows developing out West, I feel we are a few days away from resolving which model has it best.  At the moment, none of them are dealing well with the current scenario.  I can still envisage a Northerly or NE flow in the not too distant future.

[Summer Sun]

The mild end to tonight's ECM is not supported by the ens which instead stays closer to 0. Up to the 28th all looks ok beyond this is where the 2 differ

[DanBaynes]

Is there a website where i can compare different models without having to keep switching tabs?

[Mike Poole]

5 minutes ago, Decemberof2010 said:

Does anyone know what time the CMA and NASA models come out??

LOL, CMA 12z is an unmitigated disaster for cold T240:

While we're at it FIM9 is even worse, T192

NASA still showing 0z.

Hope that helps.

But as has been said, the issue is ~T120, so anything after that is nonsense.

[Summer Sun]

2 minutes ago, DanBaynes said:

Is there a website where i can compare different models without having to keep switching tabs?

You can see most of the main models together here https://www.meteociel.fr/cartes_obs/comp_panel.php

[Man With Beard]

It's interesting following all the hope and downs in here the past few days... but the GFS parallel has not moved that far from its D5-D9 evolution between 5 days ago and now, on any run... I'm starting to fall in love with it as much as I love the clusters 

[DanBaynes]

2 minutes ago, Summer Sun said:

You can see most of the main models together here https://www.meteociel.fr/cartes_obs/comp_panel.php

Thanks ss, 

[Decemberof2010]

4 minutes ago, Mike Poole said:

LOL, CMA 12z is an unmitigated disaster for cold T240:

While we're at it FIM9 is even worse, T192

NASA still showing 0z.

Hope that helps.

But as has been said, the issue is ~T120, so anything after that is nonsense.

Damn! Thanks for the effort. Looks like my straw jar is empty

[summer blizzard]

So the models tonight (bar GFS) are generally bad because of our first hurdle at day 5 which impacts events at days 6 and 7. 

So at day 5 we arrive with two hurdles to overcome.. 

1) Will the trough split sufficiently 

2) Will the high to our north sink

So essentially here the GFS, Euro and UKMO illustrate all three examples of how things can go.

1) UKMO day 6 and 7 chart essentially shows the failure here (first UKMO run to do so). So on the UKMO we arrive at days 5-6 with the high to our north intact and a Euro Low (UKMO led the pack developing this about 24 hours before the others) however it fails by day 7-8 because unlike the GFS there is insufficient disruption which means a rounder low and the Iberian High gets sucked north.  

2) Euro actually has more or less sufficient disruption but between days 5 and 6 it drops pressure by ~30mb around Salvabard. This means that the high sinks too far and although the trough struggles and potentially produces a snow event as it moves in, the Atlantic low eventually wins because the sinking high cuts off the Euro Low. UKMO and GFS do not sink the high. 

..

GFS is essentially the example of what happens if everything is perfect. We get sufficient disruption, we get no low to the north and so by day 7 we have a cyclonic easterly with uppers sufficiently cold that i am lamppost watching.

....

I get the sense going by the big 3 plus GFS(P) that the Euro is probably wrong in developing a significant low to sink the high. No other model shows this. 

Our problem is in the Atlantic where the GFS(P) basically blows up a monster low and the UKMO just has any disrupting trough too weak. 

..

On the whole i am not as bullish as Steve Murr but neither do i think the Atlantic has won yet. 

Edited November 20, 2018 by summer blizzard

[jam]

1 hour ago, Geordiesnow said:

The rounded low has indeed remained large on the UKMO and has now developed a secondary low, you would suspect it would follow the ECM basing on that chart but probably too hard to tell from that chart. 

Love these charts .. you could become fully knowledgable on the Amazon basin but can’t even see Essex 

[Seasonality]

1 hour ago, MattStoke said:

Supposedly the Met Office do look at the JMA output. That’s been said on here in the past anyway. Even though it’s not one of the main models for our part of the globe.

The old cliché on here is that THE Japanese model is 'well respected' or 'highly regarded' by the met office. Only when it shows cold though

[Geordiesnow]

4 minutes ago, jam said:

Love these charts .. you could become fully knowledgable on the Amazon basin but can’t even see Essex 

To be fair you can say that about many members on that analogy when the cold tinted specs are worn when you see constant speculation like theres definately going to be significant upgrades etc when infact, not one person has any clue what the next set of runs will definately be especially in battleground/blocking set ups like this. 

Besides my reading on the chart is as of follows, the deeper secondary low that forms will roll along the developing ridging Azores high and get close to the UK, it certainly looks like that when you look at the flow of the isobars and how secondary lows behave. I might be wrong and to be honest, its all fairly irrelevant because the next UKMO run could show something completely different. 

[booferking]

ICON more blocked on 18z around Greenland area.

[jam]

1 minute ago, Geordiesnow said:

To be fair you can say that about many members on that analogy when the cold tinted specs are worn when you see constant speculation like theres definately going to be significant upgrades etc when infact, not one person has any clue what the next set of runs will definately be especially in battleground/blocking set ups like this. 

Besides my reading on the chart is as of follows, the deeper secondary low that forms will roll along the developing ridging Azores high and get close to the UK, it certainly looks like that when you look at the flow of the isobars and how secondary lows behave. I might be wrong and to be honest, its all fairly irrelevant because the next UKMO run could show something completely different. 

I was only commenting on the geographical layout .. a world of weather and if weather is from the East then Britain is