Model output discussion - is the beast awakening?

[sheikhy]

1 minute ago, nick sussex said:

The ensembles seem to be going one way and the ops in a different direction.

The concern is that the higher resolution ops should normally have a better handle on shorter term set ups .

I think tonight is going to be either a capitulation by the ops towards the colder solutions or we’re going to see the ensembles to start jumping ship.

I can’t see much middle ground here because of the nature of the set up . 

Whose right nick ecm or gfs??cmon gimme an answer dont sit on the fence!!

[bluearmy]

So six hours on .....what have we learned ??.

[Jason M]

4 minutes ago, nick sussex said:

The ensembles seem to be going one way and the ops in a different direction.

The concern is that the higher resolution ops should normally have a better handle on shorter term set ups .

I think tonight is going to be either a capitulation by the ops towards the colder solutions or we’re going to see the ensembles to start jumping ship.

I can’t see much middle ground here because of the nature of the set up . 

Think you have hit the nail on the head here. At days 5 and 6 it’s all about the opp runs. If the opps broadly land in the same place the ensembles will inevitably follow. If the opp is an outlier at day 5 I just assume it’s the ensembles that are wrong.

 

Edited January 31, 2021 by Jason M

[kold weather]

5 minutes ago, Man Without Beard said:

I'd still give the GFS 6z a 6 or 7 out of 10 for southern regions regarding cold prospects. Of course, not like the 10 out of 10 for northern areas, or recent parallel runs. But there's still a lot of messy slightly marginal snow events.

I think being very objective a 6 would probably be fair for further SW as there is a snow-rain event that does develop and maybe E.Anglia, maybe a 4-5 in the SE, down here its a borderline poor run IMO. Though of course its well within the realms of shifting a touch south and being far better down here as well.

I still worry though that the short term is showing clear movement towards the ECM solution of holding the LP longer and longer near N.UK. If it holds much longer than the 06z GFS is showing then that easterly is going to go the way of the dodo very rapidly in just one model suite due to the knockon ramifications 

 

[Jason H]

2 minutes ago, bluearmy said:

So six hours on .....what have we learned ??.

It's still going to get colder at the weekend

[blizzard81]

2 minutes ago, bluearmy said:

So six hours on .....what have we learned ??.

That the ecm op is on the money unfortunately. 

[SqueakheartLW]

My catch up update after my night off looking at the models and this forum

GFS 18z

Just like yesterday morning I have several models and runs to get through and first I have the GFS 18z average charts from the peak of the cold spell at 162 hours away

Just like the recent runs we maintain an overall average easterly but like the most recent high pressure dominated in general so little snow away from the south with this average setup. The 850hpa temperature average of the ensembles comes out at -8.8 which is -7.3 below the long term mean. This is a 0.3 downgrade from the 12z but in the grand scheme of things this probably won't make much difference. The anomaly chart maintains those nice blue colours over the UK too.

Mildest 3 charts at 162 hours away

3rd     Member 1     850hpa temp -5.7

2nd     Member 24     850hpa temp -5.2

1st     Member 14     850hpa temp -3.8

Coldest 3 charts at 162 hours away

3rd     Member 17     850hpa temp -10.8

2nd     Member 11     850hpa temp -10.9

1st     Member 3     850hpa temp -11.8

Mildest doom and gloom chart from the 18z GFS

Member 23     +252 hours     850hpa temp 6.9

Coldest fantasy chart from the 18z GFS

Member 8     +342 hours     850hpa temp -16.0

GFS 00z

Time to compare GFS 18z now with today's 00z. First we have the average charts as usual and this time the peak of the cold spell is 168 hours away

The overall 500hpa mean shows an average easterly again and this time it looks to be a bit of an upgrade to the overall pattern as we have more of an average beasterly now compared with the 18z. This is good news for snow fans and could mean a lot more ensemble members have this setup. The 850hpa temperatures have dropped now to an average new low of -9.3 which is -7.2 below the long term mean. This continues the general trend for the core of the cold spell to get colder and colder. It is -0.5 colder than the 18z was and -0.2 colder than the previous coldest run of yesterday's 12z. The anomaly chart maintains those nice blue colours over the UK.

Mildest 3 charts of the 00z at 168 hours away

3rd     Member 11     850hpa temp -4.6

2nd     Member 26     850hpa temp -4.3

1st     Member 29     850hpa temp -0.9

Coldest 3 charts of the 00z at 168 hours away

3rd     Member 20     850hpa temp -12.7

2nd     Member 30     850hpa temp -13.4

1st     Member 27     850hpa temp -14.3

Mildest doom and gloom chart from the 00z GFS

Member 29     +336 hours     850hpa temp 11.9

Coldest fantasy chart from the 00z GFS

Member 27     +168 hours     850hpa temp -14.3

GEM 00z

Time to get onto today's GEM and how does it compare with the 12z yesterday. Today's average coldest point of the predicted cold spell comes out with 850hpa temperature average of -6.7 at 150 hours away which is -5.3 below the long term mean. Still less keen than the GFS for a very cold spell but at least this is an upgrade to the colder spell by a small -0.2 compared with the 12z.

Mildest 3 charts of the 00z GEM at 150 hours away

3rd     Member 11     850hpa temp -0.7

2nd     Member 14     850hpa temp -0.4

1st     Member 16     850hpa temp -0.3

Coldest 3 charts of the 00z GEM at 150 hours away

3rd     Member 18     850hpa temp -10.2

2nd     Member 3     850hpa temp -10.3

1st     Control     850hpa temp -10.6

Mildest doom and gloom chart of the 00z GEM

Member 6     +366 hours     850hpa temp 9.0

Coldest fantasy chart of the 00z GEM

Member 10     +366 hours     850hpa temp -12.7

GFS Extended

Finally I shall have my daily look at the GFS Extended and see how it compares with yesterday's run. First we have the average charts for the coldest point of the predicted cold spell. In this particular case it is from 192 hours away

As with yesterday's extended run we are still showing an average easterly which is in line with the main GFS runs so still very much on track for the cold spell. The 850hpa temperature average for the latest extended run comes out at -8.8 which is -6.7 colder than the long term mean and a nice -1.0 upgrade to the cold compared with yesterday's extended run. The anomaly chart reflects this with slightly deeper blues over the UK

Mildest 3 charts of the GFS extended at 192 hours away

3rd     Member 19     850hpa temp -4.1

2nd     Member 22     850hpa temp -3.9

1st     Member 7     850hpa temp -3.1

Coldest 3 charts from the GFS Extended at 192 hours away

3rd     Member 21     850hpa temp -12.5

2nd     Member 17     850hpa temp -12.6

1st     Member 15     850hpa temp -13.4

Mildest doom and gloom chart from the GFS Extended

Member 30     +540 hours     850hpa temp 10.6

Coldest fantasy chart from the GFS Extended

Member 7     +330 hours     850hpa temp -15.7

[MattStoke]

20 minutes ago, MattStoke said:

Could be a ‘surprise’ dusting for some tonight according to the Arome.

 

Aperge pushes Tuesday’s snow risk southwards.

The Harmonie too with a snow risk for many tonight.

Edited January 31, 2021 by MattStoke

[Chesil View]

7 minutes ago, Man Without Beard said:

I'd still give the GFS 6z a 6 or 7 out of 10 for southern regions regarding cold prospects. Of course, not like the 10 out of 10 for northern areas, or recent parallel runs. But there's still a lot of messy slightly marginal snow events.

Totally appreciate you're commenting on the actual op run. MWB but as I mentioned earlier a 150 /200 mile shift south on that extended run and you have the current Meto extended in chart form and that sort of correction on a global model is well within the range of error.  Interesting model watching times.

 

 

 

[snowice]

3 minutes ago, bluearmy said:

So six hours on .....what have we learned ??.

We are all mad?

[cuckoo]

Hoping these 'outlier' Ops don't prove to be trendsetters. Massive 12z's later.

[IDO]

6 minutes ago, That ECM said:

ECM has shown solid gold cold? You love a dramatic build up and then find the misery gfs 06z is fine. Let’s see where we are after the 12z’s.

No idea as the ecm op never goes beyond d10, but the control had many runs showing very cold easterly/NE'ly winter wonderland beyond d10, so yes both ecm and gfs looked very good in FI.

Anyway we should see the trend by the 12z, certainly the 06z op is out of kilter with the ensembles (only saw one that was similar!). However at this range the ops are usually the place to look so...difficult one.

 

[nick sussex]

1 minute ago, sheikhy said:

Whose right nick ecm or gfs??cmon gimme an answer dont sit on the fence!!

I’d have been less concerned if the GFS was being the grinch . Not sure anyone knows how this is going to turn out . It’s quite bizarre because normally when the op starts losing interest the ensembles start moving quickly . The ECM has had now 4 poorish runs so you would have expected the ensembles to be fleeing the sinking ship by now . When I looked at today’s ECM op I was quite surprised to see its ensembles .

[Jason M]

2 minutes ago, bluearmy said:

So six hours on .....what have we learned ??.

That in the SE it’s going to me more wet, wet, wet than snow patrol?

joking aside if you live away from the far south East things probably look very good still. It’s just a bit more iffy yet again in the areas that keep missing out this winter.

[MATTWOLVES 3]

12 hours ago, Icebox said:

With respect Matt... you have had your snow fix, many of us are yet to see a flake blowing in the wind!

Mate it's not really about me coming on here and saying I've had a snow fix..now let's get -20 uppers in place so Thames streamers can bury the SE.. its about a cold spell setting up that could deliver snow for many and bring a more prolonged spell of cold conditions.. im not looking at all the charts and aiming just for a snow fix for the Midlands..some of the sypnotics on show are really good,but let's face it if your gonna spend your time looking for -20 uppers your gonna be disappointed most of the time. Even the 2018 event only lasted a few days.

In the shorter term snow could cause quite a few problems from Tuesday into Wednesday,unfortunately many are gonna say its a Midlands North event again...But its the weather and I have know control over it,if I did I would submerge you all.

ECM op is now getting tiresome,even its own ensembles are thinking about giving it up for adoption. UKMO looks solid..theres alot going on next week,try and enjoy it unfold.

[TEITS]

1 minute ago, nick sussex said:

The ensembles seem to be going one way and the ops in a different direction.

The concern is that the higher resolution ops should normally have a better handle on shorter term set ups .

I think tonight is going to be either a capitulation by the ops towards the colder solutions or we’re going to see the ensembles to start jumping ship .

I can’t see much middle ground here because of the nature of the set up . 

Normally I would agree if it wasn't for this mornings UKMO.

Very complicated set up really. The midweek low has one shortwave moving E, another S and the main low remains in situ and then tries to move N!!

I shall stick with what I said earlier and that is this low will move S along with the shortwave at a much faster pace than what the ECM/GFS is suggesting. The ECM can be wrong with the predicted snowfall for this weekend and early next week being dreadfully way off from its predictions a few days ago. I said as much at the time because its forecasts never made any sense to me.

On a positive note you could argue that whilst the 06 GFS is poor early on, the latter stages are far better than a few days ago. So its swings and roundabouts really as I do not expect this to be our last chance. Seems N blocking will continue to be a feature for a while yet.

[kold weather]

5 minutes ago, snowice said:

We are all mad?

I don't think we've only just learnt that, think we've all known it for quite some time now!

Stinker of the day by the way goes to this run. The ECM 00z isn't that far removed from this set-up either, which is obviously a concern:

[carinthian]

9 minutes ago, nick sussex said:

I’d have been less concerned if the GFS was being the grinch . Not sure anyone knows how this is going to turn out . It’s quite bizarre because normally when the op starts losing interest the ensembles start moving quickly . The ECM has had now 4 poorish runs so you would have expected the ensembles to be fleeing the sinking ship by now . When I looked at today’s ECM op I was quite surprised to see its ensembles .

Well Nick, Arpege latest starting the delay of the milder air by holding the colder flow across from the Low Countries into Northern England. Looks like a freezing day for the North of England on Wednesday going by this chart.. I think there will be further resistance in the models this evening.

C

Edited January 31, 2021 by carinthian

[sheikhy]

9 minutes ago, MattStoke said:

The Harmonie too with a snow risk for many tonight.

Gota keep a very close eye on the radar today!!temps and dew points are perfect for snow across england!!

[Tim Bland]

End suggest the op was too slow bringing the low south and too quick to remove the cold. I expect the ECM to move the low further south later and then the GFS / GEFS to become slower with its progression. Halfway house is almost always the result with these things 

[nick sussex]

1 minute ago, TEITS said:

Normally I would agree if it wasn't for this mornings UKMO.

Very complicated set up really. The midweek low has one shortwave moving E, another S and the main low remains in situ and then tries to move N!!

I shall stick with what I said earlier and that is this low will move S along with the shortwave at a much faster pace than what the ECM/GFS is suggesting. The ECM can be wrong with the predicted snowfall for this weekend and early next week being dreadfully way off from its predictions a few days ago. I said as much at the time because its forecasts never made any sense to me.

On a positive note you could argue that whilst the 06 GFS is poor early on, the latter stages are far better than a few days ago. So its swings and roundabouts really as I do not expect this to be our last chance. Seems N blocking will continue to be a feature for a while yet.

Hi Dave good to see you posting again .

The UKMO saved my iPad from being flung across the room in disgust ! If the ensembles had started moving on mass this morning especially the ECM ones then I would have definitely feared the worst . I really don’t remember a similar scenario in the past . We’ve seen many easterlies implode but normally the ensembles follow quickly at least by the second poor op run .

This time we’re not dealing with the trigger shortwave but the limpet shortwave !

[MJB]

The Control has behaved very well this morning 

[winterof79]

14 minutes ago, bluearmy said:

So six hours on .....what have we learned ??.

That the MET have upgraded their warning from tomorrow through Tuesday. If only we could only look 48 hrs in advance....

[Timmytour]

10 minutes ago, nick sussex said:

The ensembles seem to be going one way and the ops in a different direction.

The concern is that the higher resolution ops should normally have a better handle on shorter term set ups .

I think tonight is going to be either a capitulation by the ops towards the colder solutions or we’re going to see the ensembles to start jumping ship.

I can’t see much middle ground here because of the nature of the set up . 

Agree this is a concern.... I tend to think the ensembles are often late to the party of trends first picked up by the ops and are still catching up with the previous trend as the ops move to another.

I'm not sure what winter really parallels this one.....there have not been many for sure, so you do wonder how useful the algorithms can be.  I don't know what algorithms would have been fed into the systems to allow for the UK to bathe in freezing temperatures for an entire month but they certainly will have been swamped by those indicating that the Atlantic sweeps through.  That's why, IF we manage to  really connect into some of that deep cold pool to our north east, I'd be more confident that we could hang on to it for longer than the models might suggest.  However, we know from experience that connecting into such a cold pool in a manner that suggests longevity is an extremely rare thing, and, despite what may be considered to be a lack of associated algorithm material to promote it, its something we see more in the models than we do in the weather.

 

(btw...I have no idea whether the context I am using algorithms in is correct....it's just how I have them in my head!)

[Tim Bland]

11 minutes ago, MattStoke said:

The Harmonie too with a snow risk for many tonight.

I keep looking at the radar thinking the models are way off for today!  ECM had some snow for the south west and Wales with a bit into the south but I wouldn’t be surprised if more of the west mids and central south see something later