Model output discussion - cold spell approaching?

[Blessed Weather 9,008]

After the recent SSW there are signs that the models might be homing in on the outcome with a spell of cold and snowy weather possible for the UK. So a good time for a new thread to continue discussions.

Please only discuss the model output in this thread, and as ever please also keep it friendly and respectful of others views.

With it likely to get very busy in here, can we please not use the thread for congratulations or thanks type posts - instead could we use private messaging or the 'like' or 'thanks' button. Thanks. 👍

Some alternate threads if you don't want to discuss the models:

Winter chat, banter, moans and ramps
Stratosphere and Polar Vortex watch
Regional Chat

Model Output And Charts On Netweather:
UKV (Extra subscribers)
GFS
GEFS Ensembles
ECMWF
ECMWF EPS
NetWx-SR (3km)
NetWx-MR (9km)
Met Office (UKMO)
Fax
GEM
GFS Hourly

Model Comparison
Global Jetstream
Stratosphere

Edited January 11 by Blessed Weather

[Osbourne One-Nil 3,318]

Please also note, this is a community and everyone has the right to air their views. Please do not dominate the discussion or feel the need to respond to every post. It moves too quickly if people do that. 

Finally, as Malcolm says, if you want to thank someone, use the thanks button!

[Met4Cast 12,211]

Can't help but chuckle at those suggesting this is "nailed on" now, after the complete despair in here last night when just about every model collapsed the high. The GFS & ECM were fairly big outliers, indeed the EC Det was in a minority cluster later on in the run.

How anyone can see an ensemble chart with a spread that large and say the pattern is "nailed on" boggles the mind. Will it be turning colder again? Yes. I think we can be certain of that, will it be bitterly cold & snowy? Possibly, but that remains a lower probability at the moment. 

Certainly some beautiful synoptics & snow charts out in the extended this morning, but until we start seeing more support for it, it's difficult to say exactly where we're heading.

[Jamie M 2,087]

   
 

Good FAX chart for the north, bad one for the south with constant rain in the south for days on end whilst a caking in the north.

Edited January 11 by Jamie M

[General Cluster 62,928]

A selection of lovely charts here, from today's GFS 0Z... But, they're between T+270 and 384hrs, so hardly 'nailed on' IMO:👍

    

    

And here are the GEFS Temp Ensembles, which (after a spell of marginality) fly off in all directions... Nailed? Really?🤔

     

But, on the other hand, the NH Profiles still show promise:

    

    

😁

[Jamie M 2,087]

Agree with all the posts above.

Never gonna be fully nailed on with events like this at this sort of time range especially with so much scatter at such short range.

 

EC46 coming out today so will have to see what that holds.

[Jon Snow 81,875]

Looking at the Gfs / Ecm 0z ops..next week could be fun for snow fans..and the timeframe for the change is very much in high res, around T+144 / 168 hours!...fingers crossed 🤞...we’ve had the rug pulled from under us so many times but I’m cautiously optimistic this time!😜

Edited January 11 by Jon Snow

[Tim Bland 13,982]

I think the word ‘cold’ is subjective but to me (in the south) anything below 4cis cold and with the right DP and uppers you can start thinking about snow once you start falling below that. I’m not after historic, bitter cold with sub -10s at night and endless ice days, just a bit of snow would be nice!  In that respect the ensembles are fairly ‘nailed’ for a cold spell after the weekend if you look at the amount of runs below 5c in the south...

[Anthony Burden 938]

Very interesting charts this morning at 144 hrs UKMO and GFS holding the high pressure 

to our west while ECM and GEM going for the high to sink south and low pressure moving 

in from the north.Will of course make a big a big difference to what happens in the future 

Synoptics,one to watch very carefully.

 

[Battleground Snow 5,898]

Definitely won't be decided today.

Icon looks like it would go onto make a ridge

The low  is 10mb higher than the 00z run for the same point, which could change FI . A tense day ahead I think.

 

[sheikhy 4,593]

Models are all over the place!!!!shortwaves everywhere around us and when that happens it NORMALLY dont end very well for us cold and snow lovers!!!!

[Alexis 506]

49 minutes ago, Met4Cast said:

Can't help but chuckle at those suggesting this is "nailed on" now, after the complete despair in here last night when just about every model collapsed the high. The GFS & ECM were fairly big outliers, indeed the EC Det was in a minority cluster later on in the run.

How anyone can see an ensemble chart with a spread that large and say the pattern is "nailed on" boggles the mind. Will it be turning colder again? Yes. I think we can be certain of that, will it be bitterly cold & snowy? Possibly, but that remains a lower probability at the moment. 

Certainly some beautiful synoptics & snow charts out in the extended this morning, but until we start seeing more support for it, it's difficult to say exactly where we're heading.

It's not nailed on at all. But that ensemble graph shows excellent agreement for it to turn colder, so not "low probability" in the slightest. The scatter starts immediately after the cold arrives, so yes, it could turn milder after one day.

[Broadmayne blizzard 3,711]

Interesting to see the ECM move towards the gfs solution this morning.  If it was doing this at T48 opposed T 192 I would be far more convinced that they had both hit on the right solution.  This could of course end up being a Dec 2010 situation where the models come together early and stick. But those situations in regard to snow and cold are rarer than rocking horse droppings.

So I would suggest that any back slapping about having called it or cries of it’s nailed on  be put firmly on the back burner. It’s never nailed on until the meto tell us it is either via the modelling or the extended outlooks.  All we are seeing this morning is the op runs that go that far agreeing on an output more than seven days out. That and nothing more.

I really hope as a cold and snow lover that it comes off as shown or even better than shown ( and of course the time lag does mean the charts could improve yet more) However especially for newbies it is only fair that experienced  forum members should point out that we have been eight days out from plenty of phantom cold and snowy spells through the internet era.

The best thing to do with super wintry charts at this range is to travel with hope rather than expectation.  

Edited January 11 by Broadmayne blizzard

[Penrith Snow 1,647]

Fantastic charts this morning, brightens up another  miserable lockdown Monday, the weather recently has certainly been a nice antidote to the depressing Covid situation which has turned life into such a bore.

Anyway, the models and so nice to see them converging onto a cold spell commencing around the 19th, this date has actually has been coming into focus for a few days now. What a really like about the output from the 19th is the snowy potential with both ECM and GFS, this wouldn't be a dry spell or one where we need to worry about the uppers, if it comes off it has all the markings of a  classic.

However, as others have said the only way is down from here and I suspect down grades will occur, if this was any other winter downgrades would be  certain but with the SSW hopefully less likely.

But it still isn't nailed on by a long way and please guys no more Willy waiving and 'I was right' comments, the nice thing about this forum is the feeling that we get of all 'being in it together', plenty of other places to go if you want confrontation or even just adulation.

Just got to have another look at those 850mb charts on GFS, is it a dream?

Andy

Edited January 11 by Penrith Snow

[Valleyboy 134]

There’s been a lot of booms this morning.  My advice is to wait for the main models to agree 4 / 5 days out, then confidence can be high, especially if UKMO is on board.  You can then boom away! ☺️

[feb1991blizzard 23,102]

AHEM! - ECM mean needs improving before any celebrating can begin. Flattening underway by 240. And i don't see any enthusiastic posts about the extended range so doesn't look like there's a big enough cluster that builds another one.

Edited January 11 by feb1991blizzard

[Mr Frost 12,696]

1 hour ago, Jamie M said:

    264.24 kB · 0 downloads  
 

Good FAX chart for the north, bad one for the south with constant rain in the south for days on end whilst a caking in the north.

Yes - spot on mate.

Could be an absolute pasting for the North/North East at times! 

Few UKV snapshots below.

Please excuse the sheer number of charts posted...trying to squeeze in lots of wintry potential for many parts of the UK! 😀

Wednesday 21:00

 

Thursday 06:00

 

09:00

 

12:00

 

15:00

 

 

Saturday 00:00

 

03:00

 

All the above subject to change/timing but great to see the snowfall risk (higher ground especially) once again within the semi-reliable timeframe. 

Charts/models looking great in the mid/long term - lots to be excited about!

Nailed on though? Nah...let’s get these big proper snowy boom charts into a reliable timeframe before all that chat. 

All the best to you all! 

Edited January 11 by Mr Frost

[Anthony Burden 938]

Still so much uncertainty in charts from 144 hrs  my tip do not rubber stamp any scenario 

yet,look for agreement and consistency in the charts hopefully next 24 hrs/48hrs,

and at least upto 144 hrs/ 168hrs.

[Penicuikblizzard 2,874]

7 minutes ago, Mr Frost said:

Yes - spot on mate.

Could be an absolute pasting for the North/North East at times! 

Few UKV snapshots below.

Please excuse the sheer number of charts posted...trying to squeeze in lots of wintry potential for many parts of the UK! 😀

Wednesday 21:00

 

Thursday 06:00

 

09:00

 

12:00

 

15:00

 

 

Saturday 00:00

 

03:00

 

All the above subject to change/timing but great to see the snowfall risk (higher ground especially) once again within the semi-reliable timeframe. 

Charts/models looking great in the mid/long term - lots to be excited about!

Nailed on though? Nah...let’s get these big proper snowy boom charts into a reliable timeframe before all that chat. 

All the best to you all! 

Looks a good high ground event 150m+ will do well ❄️

[chionomaniac 31,112]

Early days with the 06GFS, but I think I can see better angle on the close trough and better amplification out west.

Nothing is ever nailed on until the snow has settled on the ground.

[SLEETY 5,612]

Lol I have seen cold spells disappear within t+96 range so until a cold spell get down to at least +96 then be very careful of calling it nailed-on,especially at the timeframe being shown,and even the so called semi reliable timeframe isnt nailed on in the final outcome and gfs was showing mild crud at the same timeframe yesterday!

Nice to look at these cold charts,but they havent verified yet, and  to be honest ECM wasnt that great anyway!,and its always ahead of gfs in verification stats even if its supposed to be not as good as gfs in the greenland region🤣

[Turnedoutniceagain 1,415]

1 minute ago, SLEETY said:

Lol I have seen cold spells disappear within t+96 range so until a cold spell get down to at least +96 then be very careful of calling it nailed-on,especially at the timeframe being shown,and even the so called semi reliable timeframe isnt nailed on in the final outcome and gfs was showing mild crud at the same timeframe yesterday!

Nice to look at these cold charts,but they havent verified yet, and  to be honest ECM wasnt that great anyway!,and its always ahead of gfs in verification stats even if its supposed to be not as good as gfs in the greenland region🤣

I remember the greatest E'ly "that we never had" in Feb' 2006. Completely disappeared at T36 - I'm still having counselling for it.

[XtremeUKWeather 236]

Low south of Greeland just gone on 6z

[TSNWK 2,586]

Just now, XtremeUKWeather said:

Low south of Greeland just gone on 6z

Will that mean nothing to pump up the Greenland height in this run?

[TSNWK 2,586]

looks better to me at 168 than 00z 174