Model Output Discussion - cold spell to end Autumn

[Eskimo]

Windytv has a precipitation model for the ECM which looks nice. 

https://www.windy.com/?rain,2017-12-10-18,52.776,-0.308,6,i:p,m:e4Zaf6f

[Allseasons-Si]

1 minute ago, bluearmy said:

The rules are that if a couple runs are not as good as the previous continuity it's isn't a downgrade. You need around four poorer runs to constitute a downgrade. One better run, however, is an upgrade ?

We have only had one

but i get your example

control better than the op at 174 though,but too far out at that stage to take gospal of.

[Winter Hill]

4 minutes ago, markw2680 said:

Tbh I don’t think it’s either it’s just another variation that’s pretty much a week away, details are going to chop and change, pretty sure if it turns out as the 18z suggests then we will be pretty happy

Markw.

I'l be more happy when the UKmet. And the ecm are both singing from the same Hymn sheet. 

Im always nervous with the Gfs

[ribster]

13 minutes ago, Winter Hill said:

Was the 18z an upgrade then ? 

Or have 2 features vanished from the 12z 

I'm a coldie but I'm just replying to what I see. 

What is the problem with that ?

 

Any chance of dropping this now, it's getting awfully tiresome. I think we all agree the general cold theme is there. Troughs, polar lows, disturbances, front edge, back edge, knife edge yada yada yada...

Edited December 2, 2017 by ribster

[Paul]

Can we drop the 'troll' stuff please, if you think a post is a problem then report it - if you react to it, and particularly if you react by calling someone a troll then all you're doing is increasing the risk of the thread running off the rails. 

[ColdFront80]

Notice Thursday is looking like the mildest day of the week down in London. 

[karlos1983]

16 minutes ago, Winter Hill said:

Was the 18z an upgrade then ? 

Or have 2 features vanished from the 12z 

I'm a coldie but I'm just replying to what I see. 

What is the problem with that ?

 

Well I’m not really sure what you’re  seeing. All i see is next week starting mild, ending very cold with snow chances plentiful. I’ve backed up why with charts, and van Gough esk drawings, whereas you’ve just given an opinion which seems a bit wide of the mark, if you don’t mind me saying so?

I’ve been pretty much glued to this forum and the models for what seems like a lifetime, when I see a downgrade, believe me i’ll say it. This is no downgrade.

you’re  well within right to comment and add to the forum, but every now and then if people don’t agree, you might be pulled up on it. That’s all  

18z short ens are no downgrade 

 

Edited December 2, 2017 by karlos1983

[Frosty.]

The GEFS 18z mean looks good..cold blast on the way!

[nick sussex]

I think it’s been a good day for those wanting a spell of colder weather and the upstream pattern looks quite stable with NOAA expecting the positive PNA to last until at least  the middle of the month.

This means there’s a window of opportunity for some snow.

After last December’s horror show for coldies it’s a welcome change. This trend to drop low pressure se can always evolve further with high pressure developing to the ne.

 

 

[karlos1983]

2 minutes ago, nick sussex said:

I think it’s been a good day for those wanting a spell of colder weather and the upstream pattern looks quite stable with NOAA expecting the positive PNA to last until at least  the middle of the month.

This means there’s a window of opportunity for some snow.

After last December’s horror show for coldies it’s a welcome change. This trend to drop low pressure se can always evolve further with high pressure developing to the ne.

 

 

Are we code Green lol

Edited December 2, 2017 by karlos1983

[Man With Beard]

Must say I thought the 18Z was pretty good? Ok not sensational like the previous few runs but did anyone take those as gospel anyway?? Key principles are still there - an arctic blast with a four day window for snow. So it shows the initial low as rain not snow - this first low is knife-edge, it still is, just this run marginally on the rain side. This particular back edge snow event may not even be settled by T6!

ECM clusters ... that "wedge" development is knife-edge too. I read it as 50/50.

So cold coming again, extras appear optional at the moment

[Allseasons-Si]

The 18z gefs mean at 240 has a marked trough digging NW/SE down towards the uk,so after this shot later next week,do we get another shot after that,one to watch.

[Frosty.]

I would ? to give more points out but I'm empty..back tomorrow for hopefully more stellar cold charts to feast our eyes on..night all

Edited December 2, 2017 by Frosty.

[bobbydog]

whatever happens, i'll be happy if we get enough snow that i can make a snowball and throw it at my kids.

if i hit one of them in the face, thats a bonus....

[Allseasons-Si]

8 minutes ago, Frosty. said:

I would ? to give more points out but I'm empty..back tomorrow for hopefully more stellar cold charts to feast our eyes on..night all

I have plenty,here you go,night mate

just to add,we have already seen snow falling last thusday evening of which was a nice surprise and could be the same next week,i feel there will be more oppertunities on the run up to Chrismas and beyond,hopefully

 

Edited December 2, 2017 by Allseasons-si

[Mokidugway]

Go easy on the Hovis ,night all 

[feb1991blizzard]

14 minutes ago, karlos1983 said:

Well I’m not really sure what you’re  seeing. All i see is next week starting mild, ending very cold with snow chances plentiful. I’ve backed up why with charts, and van Gough esk drawings, whereas you’ve just given an opinion which seems a bit wide of the mark, if you don’t mind me saying so?

I’ve been pretty much glued to this forum and the models for what seems like a lifetime, when I see a downgrade, believe me i’ll say it. This is no downgrade.

you’re  well within right to comment and add to the forum, but every now and then if people don’t agree, you might be pulled up on it. That’s all  

18z short ens are no downgrade 

 

The ones for Mainland UK are slightly better than those even, those are for somewhere in the North sea!

[nick sussex]

1 minute ago, karlos1983 said:

Are we code Green lol

Yes Code Green for the northerly!  

The CSAC  (Cold Synoptics Action Committee)  have decided though to revise the warning system because the Code Green Plus is too broad and might see panic buying of sledges across the UK.

I’m going to be introducing some extra categories tomorrow once these get voted on! 

 

[OfficialKevWX]

The 00z runs are definitely going to be interesting! 

[Allseasons-Si]

8 minutes ago, nick sussex said:

Yes Code Green for the northerly!  

The CSAC  (Cold Synoptics Action Committee)  have decided though to revise the warning system because the Code Green Plus is too broad and might see panic buying of sledges across the UK.

I’m going to be introducing some extra categories tomorrow once these get voted on! 

 

Is that a....

Edited December 2, 2017 by Allseasons-si

[Winter Hill]

1 minute ago, OfficialKevWX said:

The 00z runs are definitely going to be interesting! 

If the MetO  00z  is still good then I'll be happy.. the ECM plays ball and I'll be happy. If the GFS 00z Starts to wobble..then I'll be happy because the euros are trying to sing from the same sheet.

[cheshire snow]

6 minutes ago, Winter Hill said:

If the MetO  00z  is still good then I'll be happy.. the ECM plays ball and I'll be happy. If the GFS 00z Starts to wobble..then I'll be happy because the euros are trying to sing from the same sheet.

On that note all Happy then.

C.S

[Daniel*]

Some folk have mentioned GFS dropping the back edge snow on Thursday. ECM 12z does not do this fairly heavy PPN in S/E Britain with colder air undercutting behind the front turning to snow by evening.

 

Edited December 3, 2017 by Daniel*

[Allseasons-Si]

As for the NAO/AO,trends slightly more in favour going into neg than the last update,the NAO was going into positive but now forecasting to stay neg which is another good sign,the AO forecasting to drop too,look at the 14 day forecast(black circles),but there is quiet a scatter showing uncertainties going forward, at least they are still showing neg values

as for the strat,there is a slight warming but stops there,will look in the morning to see where we go on that,the 10 hpa temps having none of it though

30/10 hpa temps

Zonal winds at 30/10 hpa show a slight reduction in wind speeds(black circles),just need to get these into the darker blues -

 

[Guest]

Certainly very interesting model watching! Enjoy the show, the ups and downs.

https://www.netweather.tv/charts-and-data/ensembles

Thats quite a wild shift to cold and one I have money on in lingering for quite a while!