Model output discussion - Into 2021

[Allseasons-Si]

I know we are all getting a bit giddy at day ten plus charts,...but they a starting to show a down well response

C U in the morning guys for episode 4 of season 2021

[Stu_London]

yeah lets not take beyond 120 hours to seriously. 

Below average to cold locked in for 4-5 days - will some possible snow events popping up in places. 

 

[Midlands Ice Age]

9 minutes ago, Relativistic said:

You mean 1684 MIA?

Been casually observing the model thread for a number of years, but never seen a chart like this. Truly awesome.

Probably...

All I know is that it produced daytime maxs of -18C in South East England on an Easterly gale!

I wonder what power the turbines in the North Sea will create if an event similar to this unfolded?

MIA

[Uncertainty]

15 minutes ago, snowking said:

There will be some hangovers in this thread in the morning.

These are the sorts of charts I think a lot of us were expecting to see around the day 15-20 period and here they are for all to see.

Almost certainly a bit extreme and changed again with the next run - but then again, a 12 day+ reversal likely peaking at over -20m/s, this is not out of the question...it’s just probably on the very edge of the envelope

Would feel better if some more EPS members went for it SK, they’re just too generally flat at the minute to truly back the early downwelling wave evolution. But as you say, it’s there in the envelope and great to see... And plenty of time for the EPS to flip.

Saying that... You can add the JMA to our growing evening Motley Crew!

[Ice Day]

Poor GFS tonight

  

GFSP nothing to write home about

  

Nothing to see here - just standard UK winter fayre

 

 

Edited January 3, 2021 by Ice Day

[Scott Ingham]

Yet. Again.

Mild incursion 

Or just an attempt at one that adds moisture to a freezing cold UK

Tomorrow to confirm for me.

I hope so anyway to stop some of the un nessary worry about a "mild" mid month!

[Mark wheeler]

What’s the Navgem 18z up to tonight .  

[Ice Day]

OK, enough silliness!  As I stated earlier (along with many others), expect some really volatile output over the next few days before the models start settling down for the mid month period.  I honestly think what's just been thrown out is totally plausible, anything is possible at the moment.  We are currently commencing an SSW that has been described as 'extreme' (maybe hyperbole, maybe not!), and as such we have a chance of some truly exception weather.  We don't even need to throw a double 6 either.

We will see, but what a brilliant time to be a weather geek.

[Beanz]

17 minutes ago, Midlands Ice Age said:

Probably...

All I know is that it produced daytime maxs of -18C in South East England on an Easterly gale!

I wonder what power the turbines in the North Sea will create if an event similar to this unfolded?

MIA

Nothing more than normal, they disengage at a modest wind speed

[Scott Ingham]

1 hour ago, CreweCold said:

I think I say this for almost everyone here, but I hope it's the latter!

For me and ive been adamant on an extreme level. This outcome never went away its just a computer model overly semsitive to extreme parameters it coudnt decipher.

It needed human forecasting to apply logic and learnings to see past dodgy runs and dodgy ensemble sets.

The learning will be never take weather models at statostical face value when you believe the science in your head

[Mark Parsons]

35 minutes ago, Jason H said:

Lol. Look where that northerly originates from. The other side of the pole. That's never going to happen. Nice to look at though. 

Hi Jason, can you explain why the wind direction over pole to the UK would not happen ? Cheers

[Cryosphere.]

9 minutes ago, Scott Ingham said:

Yet. Again.

Mild incursion 

Or just an attempt at one that adds moisture to a freezing cold UK

Tomorrow to confirm for me.

I hope so anyway to stop some of the un nessary worry about a "mild" mid month!

spot on! i dont see anything other than an influx of percipitation too fridgid air..

[Scott Ingham]

1 hour ago, Met4Cast said:

I tweeted a few days ago saying it was likely the models (but GFS in particular) would lose the plot as the SSW began to take hold.. I think we've just seen that with the 18z and then some.

What an absolutely insane run! Snow for just about all, the cold across Siberia is something I've never seen before, a direct NE from that would be absolutely crippling & would without doubt beat the classic winters of past. 

A true classic pub run! 

Thats hit the nail on the head its easy to forecast statistically but not easy to look at a set of ensembles showimg support for mild but apply known logic and background noise to proclaim these wrong

Second guessing is a hard thing to do in forecasting so i admire you for sticking to your principles

[Mark Parsons]

25 minutes ago, Ice Day said:

Poor GFS tonight

  

GFSP nothing to write home about

  

Nothing to see here - just standard UK winter fayre

 

 

Reverse psychology GFS .....it's just churning out it's usual crap from what I can see...........

Edited January 3, 2021 by Mark Parsons

[feb1991blizzard]

2 minutes ago, Scott Ingham said:

Thats hit the nail on the head its easy to forecast statistically but not easy to look at a set of ensembles showimg support for mild but apply known logic and background noise to proclaim these wrong

Second guessing is a hard thing to do in forecasting so i admire you for sticking to your principles

 

Steep rise towards mid month, evidence is overwhelming.

[Scott Ingham]

15 minutes ago, feb1991blizzard said:

 

Steep rise towards mid month, evidence is overwhelming.

Skewed by some outrageously wrong ensemble members.

I know you have this view but as you know i strongly believe we will be hangimg on to cold weather.

Im not playing idea tennis

Well soon know the weather on the ground

[Met4Cast]

20 minutes ago, feb1991blizzard said:

 

Steep rise towards mid month, evidence is overwhelming.

A few days ago we were looking at a warming trend from the 9th. Now it's the 12th. In a couple of days time I suspect it'll be the 15th. As the SSW begins to happen, models are going to struggle to resolve what happens next, the 18z tonight is an extreme example of that, I suspect we'll see some extreme mild options being thrown out too. 

The ensembles with their lower resolution are going to struggle even more. The ECM should have a better handle on things, sure there's a slight warming trend within the mean but look at the spread of solutions, there's quite a cold clustering there also. 

Worth noting the GFS isn't interested in moving the MJO eastwards where all other models do, it's likely wrong there, and that'll have implications on what it's predicting for our side of the hemisphere too. 

Steady as she goes.. I fully expect the "breakdown" to be pushed back again. And again.. and perhaps again. I try to keep things sensible when forecasting, if anything I'm overly cautious when it comes to jumping on board with cold patterns for the UK, but I'm fully on board with this one. 

In my opinion, the ensembles showing the warm up are likely wrong. It doesn't fit.

Edited January 3, 2021 by Met4Cast

[Scott Ingham]

6 minutes ago, Met4Cast said:

A few days ago we were looking at a warming trend from the 9th. Now it's the 12th. In a couple of days time I suspect it'll be the 15th. As the SSW begins to happen, models are going to struggle to resolve what happens next, the 18z tonight is an extreme example of that, I suspect we'll see some extreme mild options being thrown out too. 

The ensembles with their lower resolution are going to struggle even more. The ECM should have a better handle on things, sure there's a slight warming trend within the mean but look at the spread of solutions, there's quite a cold clustering there also. 

Worth noting the GFS isn't interested in moving the MJO eastwards where all other models do, it's likely wrong there, and that'll have implications on what it's predicting for our side of the hemisphere too. 

Steady as she goes.. I fully expect the "breakdown" to be pushed back again. And again.. and perhaps again. I try to keep things sensible when forecasting, if anything I'm overly cautious when it comes to jumping on board with cold patterns for the UK, but I'm fully on board with this one. 

In my opinion, the ensembles showing the warm up are likely wrong. It doesn't fit.

I can vouch for you having no cold bias as we had a heated debate not long ago when you had reasons to believe we would be mild at that point 

[Scott Ingham]

Look at the ensembles knock off 3 degrees on the mean mid month.

It will be a bit warmer but it coincides wth slider/battleground/runner events

Very slight warm up

Very huge increase in snow

Then back in the freezer.

The danger is seeing a mean temp rise and thinking south westerlies when its hiding a small rise and extra moisture

[Scott Ingham]

Right so the red mean line in the next 5 days.

Watch that flatline around -5 or slightly above with every set.

Ive highlighted precipitaion

Watch that stay similar indicating moisture.

Watch for lows and short waves bumping into our huge cold pool and watch for very snowy runs from circa the 12th.

Then look for signs of this mean red 850s line taking a nose dive after the 20th when we see reversal im full swing and easterlies

[chionomaniac]

1 hour ago, feb1991blizzard said:

 

Steep rise towards mid month, evidence is overwhelming.

Lol. You will save yourself a lot of stress if you stick to looking no farther than day 10. When a sharp rise occurs in this timeframe then it is time to look up. After this timeframe ensembles will always trend to climatological mean. 

Quite often this is common but the trend stays post day 10. The significant thing about these ensembles is the below average mean up to this point- and this is far more worthy of a mention than what comes after.

[Battleground Snow]

Morning all,

How are we going to top those runs from last night?

Icon trying it's best at 168, very cold from the North. 

 

[Battleground Snow]

Ukmo v GFS at 96.

Ukmo improvement compared to its 12z with Greenland heights orientation. 

 

[Midlands Ice Age]

1 minute ago, Battleground Snow said:

Ukmo v GFS at 96.

Ukmo improvement compared to its 12z with Greenland heights orientation. 

 

Wow BS...I woke up dreaming of the  weather...

Don't you ever sleep?

MIA

[Battleground Snow]

3 minutes ago, Midlands Ice Age said:

Wow BS...I woke up dreaming of the  weather...

Don't you ever sleep?

MIA

Turn into a bit of insomniac when the output is this good!

Ukmo 120 v GFS 120. Hopefully GFS is leading the way. It has the better Greenland profile.