Model output discussion - cold spell approaching?

[Mucka]

6 minutes ago, northwestsnow said:

UKMO looks far worse to me at 144.

Iberian heights stronger...

You have to remember UKMO 144 charts look like mean charts for their lack of detail.

In reality there is trough extending W of Ireland which has yet to swing through so I expect a 168 chart would look better than people might expect. but no neither GFS nor UKMO are ideal.

Edited January 13, 2021 by Mucka

[Summerstorm]

7 minutes ago, Kasim Awan said:

Classic west based negative NAO here. Infact gets a value of >50 which is a strong westerly based -NAO. Nonetheless, the cold arrival in the UK is still likely here eventually.

Hopefully the Aleutian Ridge out in the Pacific will help and reinforce the Arctic/Greenland high if we can get sufficient WAA up the W of USA and push some of the colder air our way. 

Edited January 13, 2021 by Summerstorm

[convector]

perhaps there is some hope for the south tomorrow

 

[Battleground Snow]

The ridging into Greenland is somewhat weaker  on ukmo and GFS as the low does  not stay cut off for long, which reduces WAA into greenland and makes the ridge less robust in the early stages.

Gem is again the best solution and keeps it cut off longer, hopefully ECM will show this too. Quite a big difference at just 120.

 

 

 

[Mucka]

GeFS mean has the Atlantic low a lot further NW by 120 than the 18z mean which isn't great at all. We want it held back SW so less chance of it phasing early and preventing the trough digging down. 

Let's see if ECM can hold firm.

Edited January 13, 2021 by Mucka

[Battleground Snow]

1 minute ago, Mucka said:

GeFS mean has the Atlantic low a lot further NW by 120 than the 18z mean which isn't great at all. We want it held back SW so less chance of it phasing early and preventing the trough digging down. 

Let's see if ECM can hold firm.

Indeed, could be a case of ukmo and GFS suites, v gem and ECM at just 120.

Not good for the nerves!

Gem at 153 

[northwestsnow]

3 minutes ago, Mucka said:

GeFS mean has the Atlantic low a lot further NW by 120 than the 18z mean which isn't great at all. We want it held back SW so less chance of it phasing early and preventing the trough digging down. 

Let's see if ECM can hold firm.

Now I'm getting that sinking  feeling.

Going to wait to see if EC holds firm before disappearing off to the moan thread.

 

[O'Maille80]

The ECM has been playing catch up all winter. This doesn't look promising.

[Mucka]

8 minutes ago, northwestsnow said:

Now I'm getting that sinking  feeling.

Going to wait to see if EC holds firm before disappearing off to the moan thread.

 

It could just be a wobble.

I really hope so because it would be incredibly frustrating if this goes totally TU.

I'm sure people who were not happy with ECM will be a little more forgiving if it repeats its output this morning. 

Fingers crossed.

We just need that low to stay cut off. It is a tripple whammy when it phases just to our W.

1. it stops the cold air digging down from the trough

2. It raises heights tot he S

3. it makes the Atlantic ridge less strong as doesn't reinforce with WAA from Iberian heights as when remaining closed off

Edited January 13, 2021 by Mucka

[swfc]

25 minutes ago, northwestsnow said:

Is EC leading us up the garden path here?

UKMO just isn't playing ball.

It's a bit meh northwest I'd agree. I said the other day the closer the fi charts get the more the extrafagent charts and great winter charts are watering down. To be expected but I think this mornings output esp 0z gfs shows this. Still a colder outlook but a tempering of excitement may for many be advised

[SLEETY]

Why are the midnight runs always crud compared to the previous runs, it's nearly always like this, so annoying, maybe ECM won't be as bad, it's been more consistent recently. 

[Battleground Snow]

Difference v last night is stark on the GFS

Edited January 13, 2021 by Battleground Snow

[Battleground Snow]

Para is somewhat better at 198, so something to cling to, I fear this forum might get very frustrated if we do not see ECM hold its ground later 

Edit: by 240, para does recover to show alot of northern blocking but we are back to day 10 again.... Maybe a delayed route to cold?

 

Edited January 13, 2021 by Battleground Snow

[northwestsnow]

1 minute ago, Battleground Snow said:

Difference v last night is stark

In the words of victor Meldrew ...

' I dont believe it.'

Perhaps we have a rogue GFS op ...

But ukmo is no better, worse for me,although I take Muckas point.

Either way, we need EC to keep the faith this morning.

I be watching it from behind the sofa..

[swfc]

7 minutes ago, Battleground Snow said:

Para is somewhat better at 198, so something to cling to, I fear this forum might get very frustrated if we do not see ECM hold its ground later 

 

The actual nhp shows a slight weakening of Heighths has they build. It drifts slightly west and allows the low to quickly after leaving the esb push under the high and phase with the UK low. Its only one run as such but  All subject to change but I don't think the ec will be the be all and end all whatever it shows. Very fluid and interesting I'd say and could cause some extreme outcomes for the UK 

Edited January 13, 2021 by swfc

[Mucka]

7 minutes ago, northwestsnow said:

In the words of victor Meldrew ...

' I dont believe it.'

Perhaps we have a rogue GFS op ...

But ukmo is no better, worse for me,although I take Muckas point.

Either way, we need EC to keep the faith this morning.

I be watching it from behind the sofa..

Take solace in the MetO forecast. They finally talked about cold from Scandinavia.

From week starting Sunday Jan 17th to 24th

"winds from the north bringing cold conditions from Scandinavia across much of the country"

Edited January 13, 2021 by Mucka

[Roger J Smith]

One instance of this sort of change in model runs seems to be almost a constant feature of actual cold spells, so I would wait until the ECM and the 12z suite before getting too concerned, it may just be a case of amplified faulty input. On the GFS the cold air was building gradually until about 234h so it's at that time range that the flip-flop occurs. As we know, 234h (almost ten days) is well outside reliable model guidance time. 

Makes me nervous for the prospects of the cold spell but I wouldn't abandon the idea after just one run, we may end up with a similar reversal back to cold at 12z. 

[northwestsnow]

1 minute ago, Mucka said:

Take solace in the MetO forecast. They finally talked about cold from Scandinavia.

From Sunday Jan 17th

"winds from the north bringing cold conditions from Scandinavia across much of the country"

Cheers mate.

UKMO 850s has the cold stuff within touching distance at 144...

[Mucka]

Aperge

[Daniel]

Ensembles so far for London. Not the change we wanted this morning. Hopefully ecm will stick to its guns 

[Battleground Snow]

1 minute ago, Mucka said:

Aperge

Wow that is a very big shift, I'd expect the warning area to move south later this morning.

I've attached arome, also a shift

[Battleground Snow]

10 minutes ago, Daniel said:

Ensembles so far for London. Not the change we wanted this morning. Hopefully ecm will stick to its guns 

The colder solutions do seem to reappear after the 21st but we could do without any kind of delay.

 

[SLEETY]

If met talking about cold from scandi then this  gfs run  and its ensembles are complete junk then and should be ignored, and down goes its credibility again, useless model

[Daniel]

9 minutes ago, Battleground Snow said:

The colder solutions do seem to reappear after the 21st but we could do without any kind of delay.

 

The mean never even reaches -5. The op is clearly an outlier tho 

[Weather-history]

GFS 0z run from 3rd January for early hours today

ECM 0z version

 

GFS 0z run from 7th January for today

ECM 0z version

UKMO 0z version

 

Today

Edited January 13, 2021 by Weather-history