model discussion Model output discussion - the final third of Autumn

[Guest]

3 hours ago, Mapantz said:

Before people get too carried away, the control run was on its own from day 12.

The rest of it was meh.

Probably the first of about 83 times that’ll happen in the next four months…

[Mike Poole]

No sign of the pub run.  Have I completely misinterpreted the reason for the clocks going back?  Surely it is so that we can view the 18z while still awake!  

[Eagle Eye]

P21 gets even weirder when you look at the precipitation charts 

[Mike Poole]

2 minutes ago, Eagle Eye said:

P21 gets even weirder when you look at the precipitation charts 

Precipitation charts at T384?? Seriously, they are rubbish at T24 on GFS!  My advice is to ignore all precipitation charts on GFS and other global models, and if, and I repeat if, it gets to the point of there being snow in the immediate future, look to the high res models some of which are only running to T48 like HARMONIE; or EURO4, or ICON-EU.  They can actually be quite good, but it needs to be within T48.  

[Eagle Eye]

On 02/11/2021 at 21:55, Mike Poole said:

Precipitation charts at T384?? Seriously, they are rubbish at T24 on GFS!  My advice is to ignore all precipitation charts on GFS and other global models, and if, and I repeat if, it gets to the point of there being snow in the immediate future, look to the high res models some of which are only running to T48 like HARMONIE; or EURO4, or ICON-EU.  They can actually be quite good, but it needs to be within T48.  

I was just showing how ridiculous runs can be in Winter, am I right in saying that the control run is probably more closely decided by the average than the P1-30's and so isn't as ridiculous or do I not remember right? 

[swfc]

15 minutes ago, Mike Poole said:

No sign of the pub run.  Have I completely misinterpreted the reason for the clocks going back?  Surely it is so that we can view the 18z while still awake!  

It's running now mike. It's now 9-30 kick off

[Mike Poole]

2 minutes ago, Eagle Eye said:

I was just showing how ridiculous runs can be in Winter, am I right in saying that the control run is probably more closely decided by the average than the P1-30's and so isn't as ridiculous or do I not remember right? 

Hi @Eagle Eye!  So, the control run!  The ensemble suite is run at a lower resolution than the op run.  The P1-30 are all run with perturbations to the initial state to investigate uncertainty.  The control run (often over-posted on here, in my opinion) has a specific purpose.  It has the same starting conditions as the op run, but the lower resolution of the ensembles.  If the op and control are similar then the reduced resolution is probability not a factor, and the ensembles will be a good indicator of uncertainty.  If the control is widely different to the op, then lower resolution is probably the reason, and the rest of the ensembles should be binned.  Hope that is helpful.  

[swfc]

13 minutes ago, Mike Poole said:

Hi @Eagle Eye!  So, the control run!  The ensemble suite is run at a lower resolution than the op run.  The P1-30 are all run with perturbations to the initial state to investigate uncertainty.  The control run (often over-posted on here, in my opinion) has a specific purpose.  It has the same starting conditions as the op run, but the lower resolution of the ensembles.  If the op and control are similar then the reduced resolution is probability not a factor, and the ensembles will be a good indicator of uncertainty.  If the control is widely different to the op, then lower resolution is probably the reason, and the rest of the ensembles should be binned.  Hope that is helpful.  

Hi Mike. Isn't the mean the full ens runs totaled up. I thought also the control was more accurate than the op. I'm prob talking rubbish thanks 

Edited November 2, 2021 by swfc

[Mike Poole]

Just now, swfc said:

Hi Mike. Isn't the mean the full ens runs totaled up. I thought also the control was more accurate?? Thanks 

The mean is the average of all the ens excluding the control.  The control is as I said above, it is a lower resolution version of the op run, it is a diagnostic against the ensembles, it shouldn’t be treated as an extra op run.  

[Mike Poole]

Liking the pub run so far, and of course we are looking post day 10 for the interest.  

And I can see when people might be worried T192, not Euro heights incoming:

But it is a twofold shift, to realign the high into an Atlantic ridge, hopefully into Greenland, and a trough into Europe.  The low highlighted is the one I highlighted earlier on ECM, second down the track, maybe slightly less of a feature here, T228, let’s see:

Nope. It’s gone wrong for us T276:

Fine margins!  Let’s get this within T192 and then we will see!

Edited November 2, 2021 by Mike Poole

[swfc]

Yet again pub run in the deep depths of fi brings a cold blast from the north. It would seem a default thing atm but hey it looks nice and you never know do you

[swfc]

virtually identical to the 12z gfs control on 18z control 

Edited November 3, 2021 by swfc

[swfc]

Say hello to Mr PV 

[Ali1977]

Another interesting looking FI on the GFS Op this morning!! 

[mb018538]

A dry and mainly settled outlook for the next 10 days across the south and east in particular. Wetter in the North/West, especially NW Scotland.
Temperatures around average.

[Methuselah]

Yes, there's very little rain indicated on this morning's GFS 00Z operational as SLP looks like being generally high. With overnight fog and (to a lesser extent) frost the most likely 'hazards':

    

    

    

And, looking at the GEFS temperature ensembles, nothing particularly unusual stands out. Uncertainty excepted!

   

 

[Newberryone]

Certainly little if any signs of any substantial relaxation of those heights to the south giving way anytime soon if the overnight ecm run is to be believed. One can see that even by days 8,9 and 10 any approaching Atlantic system is kept well away to the northwest by the all too familiar area of high pressure to the south. A stubborn feature which as we all know can scupper many a dreamlike synoptic chart from materialising. The only upside being the decent drying up process it will bring about following the recent very wet spell.

[mb018538]

A chart at the end of the 6z run we don't want to see during winter. Main portion of the PV anchored over Iceland/Greenland/NE Canada. A recipe for westerlies, wind and rain in our locale.

[Methuselah]

There's an increased westerly component to the wind, according to this morning's GFS 06Z operational run. So, less emphasis on overnight fog and frost, in what would be a more unsettled pattern. But there's still plenty of time for things to change:

    

    

    

[swfc]

Morning campers. Looking at the oz and  esp 6z gfs mean I woudnt be to dispondent tbh. Hopefully over the nest week or so mjo will show its hand in the output and synoptics. Think patience is the key and you would expect runs firing up the PV to the wnw coming out of the esb. I could be talking tripe but that's my direction on it and all will be revealed.

[Howie]

42 minutes ago, Ed Stone said:

There's an increased westerly component to the wind, according to this morning's GFS 06Z operational run. So, less emphasis on overnight fog and frost, in what would be a more unsettled pattern. But there's still plenty of time for things to change:

    

    

    

La niña and eqbo influence nowhere to be seen, typical  

[swfc]

6 minutes ago, Howie said:

La niña and eqbo influence nowhere to be seen, typical  

Hi. I think the effects are more likely later this month going into December. No guarantees but the dice are loading more  favorably this winter for sure

[Howie]

Just now, swfc said:

Hi. I think the effects are more likely later this month going into December. No guarantees but the dice are loading more  favorably this winter for sure

Hopefully

[swfc]

 not a bad mean on the 6z gfs imo

Edited November 3, 2021 by swfc

[Methuselah]

11 minutes ago, swfc said:

Hi. I think the effects are more likely later this month going into December. No guarantees but the dice are loading more  favorably this winter for sure

And don't forget the (ad hoc?) 20-year Atlantification Cycle is now favourable too! If, like me, you've never heard of it, there's no need to panic; I think it might be a new one?