Model output discussion - late November

[Met4Cast]

That's a huge switch to not cold on the GEFS 6z

GEFS vs EPS & UKMO Op, which for all we know is on the extreme end of cold within its ensembles. 

[MATTWOLVES 3]

I must be still hung over.... I can't believe there is so much hanging on the GFS 6Z op runs! It's pointless comparing one run with the next one!! John holmes points this out persistently. If the 0Z is promising.... The 6Z a downgrade.... Then the 12Z an upgrade... Followed by the 18Z not having a clue.... Just were does that leave us for a day of model watching!!! I for one am confused! For me the 6Z ensembles show some promise... And I think Karl.... AKA Jon Snow pointed this out earlier! We seem to have quite a cold pool building to the NE on quite a few runs! Can we tap into it is the million dollar question!!! I would say with nearly 4 months of winter remaining, we have a good chance of it at some point... In the words of our very own legritter...... Stella's all around..... Its Friday..... Thank the lord....

[coldwinter]

2 minutes ago, Weathizard said:

GFS Mean at day 6 fairly similar to the det ECM

 

 

Very noticable from day 6/7 onwards on the GEFS that Iberian heights are growing in strength rapidly, should we not grab this early oppourinty it could be a painful few weeks with that in situ, potentially drier than recent weeks though which is positive.

 

 

The change on the GFS and the GEFS is the low pressure south of Greenland, it is deeper and it doesnt move east and there isnt enough of a ridge in between it and the low coming out of Newfoundland, if those two lows phase then the Greenland high wont happen. It is a perfectly feasible solution  for them to phase, coldies will want them not to, very tight margins as ever for the UK

[Methuselah]

3 minutes ago, Steve Murr said:

I cannot believe the total memory loss of the same old people here, thats the same ones posting the same replies as they do every year - defending the GFS when its going to be wrong.

When you have UKMO aligned to ECM & ECM mean at 120 they are NEVER trumped by an out of kilter GFS especially the 06z which is like comparing a pedigree with a stray.

So for all the neutrals who wonder if its just opinion or is it sound education over a few years lets take yesterday as a prime example of how bad the 06Z GFS is - 

UKMO 144 yest V 120 Today

That is a superb match across day 6 down to Day 5. Metronomic consistency with minimal adjustments all around the Globe.

Now look at the runt of the litter the GFS. Same timeline.

Yesterday at 144 No Greenland High, No decent arc of Cold coming through Scandi

UK in southerlies -- Look how much this model has changed in that short time span...

How anyone who indicates they follow the models can put any credibility on such a pants model - means to me they are deliberate in their attempts to derail the thread.

Back to the original well proven point 

* If the 06z goes off on a tangent through 144 then scrap it *

No-one's 'defending' the GFS, Steve (there's not a war on!)...But, summarily binning runs that don't happen to fall into 'BOOM' territory is hardly scientific...?

I have seen the verification data too -- at T+240 (if I remember precisely?) the GFS performs 2 or 3 %age points lower than both the UKMO and ECM.?

But, 2 or 3% of what? Not very much?

In the meantime (if last-year's anything to go by) the weather'll continue to make mugs out of us all!!

[frosty ground]

8 minutes ago, Steve Murr said:

I cannot believe the total memory loss of the same old people here, thats the same ones posting the same replies as they do every year - defending the GFS when its going to be wrong.

When you have UKMO aligned to ECM & ECM mean at 120 they are NEVER trumped by an out of kilter GFS especially the 06z which is like comparing a pedigree with a stray.

So for all the neutrals who wonder if its just opinion or is it sound education over a few years lets take yesterday as a prime example of how bad the 06Z GFS is - 

UKMO 144 yest V 120 Today

That is a superb match across day 6 down to Day 5. Metronomic consistency with minimal adjustments all around the Globe.

Now look at the runt of the litter the GFS. Same timeline.

Yesterday at 144 No Greenland High, No decent arc of Cold coming through Scandi

UK in southerlies -- Look how much this model has changed in that short time span...

How anyone who indicates they follow the models can put any credibility on such a pants model - means to me they are deliberate in their attempts to derail the thread.

Back to the original well proven point 

* If the 06z goes off on a tangent through 144 then scrap it *

It's pretty simple Steve, either we discus what the models show or we discuss what we want to see.

I have no issues with your comment regarding what the operation MET and ECM show. I have no issue with your comment regarding past corrections of the GFS even if it is an older version of today's model.

The fact is the GFS 06Z sits within the envelope of outcomes for all publicly available data, if you wish to throw this part of the envelope away that must mean you think its wrong and therefore know the eventual outcome which i know you don't, so it must be you want the GFS outcome to be binned because you prefer the outcome of other models.

 

[shaky]

Gota see an improvement in regards to that atlantic low at 144 hours on the 12zs!!either want it so deep that it sends a ridge up the atlantic or so really slack where it slides!!my money sits on neither and am saying we gona be in huge trouble come the time with a really flat low into the uk regardless of those mini greenland height rises!!

[Jonathan Rhodri Roberts]

So nice to see high pressure becoming more dominant down to the SW from December instead of low, I know that's not good news snow-wise but after another very wet period coming up this weekend and lasting into next week for SE Ireland, the Westcountry & S Wales a much drier spell will be very welcome by many ️

Edited November 22, 2019 by Jonathan Rhodri Roberts

[Met4Cast]

ECM clusters are interesting. All systems go at day 5 in terms of blocking

However by day 10 the biggest cluster is looking more like the GFS 6z than it is the ECM op 

So those spouting that the GFS is rubbish because it isn't showing Narnia synoptics.. the GFS 6z op is very much supported not just by it's own ensemble suite, but by the biggest EPS cluster, too. 

That low to the south of Greenland is the problem, where's Nick Sussex and his shortwave spoiler?

Edited November 22, 2019 by Met4Cast

[StretfordEnd1996]

It's not the best of GEFS suits I've ever seen and a big change from the 00z - essentially what happens after around Day 9 is virtually all members go for a much milder solution probably helped by a strong Azores High. To me it kind of paints a bit of a picture on what we can expect going forward (the 'pictures' been up in the air of late) -

00z
 

06z - showing the large uptick around the 3rd December

Long way off but it's never ideal when 19/20 ensembles are showing milder than average uppers at around Day 9 onwards

But hey lets not worry too much about that - because before that even happens we have potentially for a cold dig from the North. Most ensembles show this - with most of them being below average for the time of year around D6-9 but most of them aren't cold enough for anything too exciting, away from the usual suspects - 

I'm still looking towards the UKMO and ECM though as well as the handful of GEFS that show a decent solution for later next week with proper colder air trying to be brought in from the North

 

[coldwinter]

As said above, the EPS demonstrate it well by day 9, you can see the support for the lows phasing in the poor biggest cluster,while the other  2 smaller clusters are very good, as ever, fine margins for the UK, and as we have seen far too many times, we are on the wrong side of that margin, certainly caution required 

[feb1991blizzard]

8 minutes ago, Met4Cast said:

ECM clusters are interesting. All systems go at day 5 in terms of blocking

 

However by day 10 the biggest cluster is looking more like the GFS 6z than it is the ECM op 

S

Wished we could order a cluster 4

[SMU]

40 minutes ago, frosty ground said:

It's pretty simple Steve, either we discus what the models show or we discuss what we want to see.

I have no issues with your comment regarding what the operation MET and ECM show. I have no issue with your comment regarding past corrections of the GFS even if it is an older version of today's model.

The fact is the GFS 06Z sits within the envelope of outcomes for all publicly available data, if you wish to throw this part of the envelope away that must mean you think its wrong and therefore know the eventual outcome which i know you don't, so it must be you want the GFS outcome to be binned because you prefer the outcome of other models.

 

The model is being dismissed because of its track record is useless. It has nothing to do with what I want. Every single year since 2005 I sit here dissecting every single run.

So don't you think in 14 years > 56 Winter months + Nov & approx 1700 runs of the 06z I wont have gleaned some info.

The model will be wrong- Just like the examples Ive highlighted above & from before & every single year.

Its plain to see here you are just being deliberate in trying to derail the thread because of your agenda.

Please just leave it at that.

Todays GFS 06z 168 for reference.

 

Edited November 22, 2019 by Polar Maritime
To move discussion on..

[Met4Cast]

11 minutes ago, Met4Cast said:

ECM clusters are interesting. All systems go at day 5 in terms of blocking

However by day 10 the biggest cluster is looking more like the GFS 6z than it is the ECM op 

So those spouting that the GFS is rubbish because it isn't showing Narnia synoptics.. the GFS 6z op is very much supported not just by it's own ensemble suite, but by the biggest EPS cluster, too. 

That low to the south of Greenland is the problem, where's Nick Sussex and his shortwave spoiler?

For what it's worth, MOGREPS is fairly similar to cluster 1 as well with a return to a more mobile pattern as we move into December, so for now any blocked/cold weather is looking likely to be rather short lived, at least until mid-late December when goings on within the stratosphere could make things a little more interesting.

[Weathizard]

25 minutes ago, Steve Murr said:

The model is being dismissed because of its track record is useless. It has nothing to do with what I want. Every single year since 2005 I sit here dissecting every single run.

So don't you think in 14 years > 56 Winter months + Nov & approx 1700 runs of the 06z I wont have gleaned some info.

The model will be wrong- Just like the examples Ive highlighted above & from before & every single year.

Its plain to see here you are just being deliberate in trying to derail the thread because of your agenda.

Please just leave it at that.

Todays GFS 06z 168 for reference.

 

With respect Steve, I don’t think anyone is saying the 6z is correct, but to suggest it’s implausable and should be binned is a bit silly really regardless of whether the 6z is over progressive or not, it fits within a broad envelope of possible outcomes. Not saying it’s right, but still worth discussion and analysing.

Edited November 22, 2019 by Polar Maritime
Snipped quote.

[SMU]

3 minutes ago, Weathizard said:

With respect Steve, I don’t think anyone is saying the 6z is correct, but to suggest it’s implausable and should be binned is a bit silly really regardless of whether the 6z is over progressive or not, it fits within a broad envelope of possible outcomes. Not saying it’s right, but still worth discussion and analysing.

Look at its performance yesterday 144>120 today it speaks volumes--

[mountain shadow]

16 minutes ago, Weathizard said:

With respect Steve, I don’t think anyone is saying the 6z is correct, 

But if it is correct, it will be correct by chance rather than its programming.

I agree with Steve. The GFS 6z should never be believed unless it is similar to the Euro models at a particular time frame.

[frosty ground]

45 minutes ago, Steve Murr said:

The model is being dismissed because of its track record is useless. It has nothing to do with what I want. Every single year since 2005 I sit here dissecting every single run.

So don't you think in 14 years > 56 Winter months + Nov & approx 1700 runs of the 06z I wont have gleaned some info.

The model will be wrong- Just like the examples Ive highlighted above & from before & every single year.

Its plain to see here you are just being deliberate in trying to derail the thread because of your agenda.

Please just leave it at that.

Todays GFS 06z 168 for reference.

 

Not sure what else I can say..........

The output of the 06 Op GFS would fit in with the 0z Ensemble GFS output without being an outright outlier.

The entire Suite has moved with the operational, nothing new about that it has happened many countless times before and it has moved back, sometimes it hasn't but what history tells us is you can not throw a run away without seeing its ensembles just because its different..... hence the term more runs needed. 

I think these exchanges are useful for us all .

Edited November 22, 2019 by Blessed Weather
Edited to reflect original post in quote box now edited.

[knocker]

A glance at the EC weeklies update for the last half of December

For the 15th -22nd the salient points are:

Vortex northern Canada with trough extension mid Atlantic and minor indications of a ridge south east Greenland , Thus a

strong westerly upper flow across the Atlantic, abating in the east where the subtropical high is stirring over western Europe

From the 24th-31st

Vortex still northern Canada with some retrogression of the trough but retaining a strong westerly upper flow but noticeable negatively anonymous in the east as the subtropical high appears to be less influential.

The overall indications are temps above average with a period of changeable weather, perhaps more so in the last week, and quite likely tending towards a north south split looking at the rainfall spread

 

 

[frosty ground]

5 minutes ago, mountain shadow said:

But if it is correct, it will be correct by chance rather than its programming.

I agree with Steve. The GFS 6z should never be believed unless it is similar to the Euro models at a particular time frame.

And yet no one is saying the GFS 06z is correct.

[tight isobar]

Well steve has a valid point!!= and we find ourselves discussing this year in year out..

 

The 6z gfs is bottom of the pile...in its sister suites!!=12z =00z =18z..with most time the night run in top pack!!! @00z

 

So lets out this out with the bins!!!..

As again...we've been hear b4...many times b4!!!

Edited November 22, 2019 by tight isobar

[Tim Bland]

GFS op disagreements aside it is more concerning for me that MOGREPS only sees this as a transient cold spell, most EPS clusters and GEFS (ensembles) agree (19/20) Meteogroup (BBC forecast earlier) said brief cold spell end of next week and they have more output to digest and come to this forecast than us. Will be interesting to see the meto long range update shortly.  Still time for change and all the models are just forecasts, but odds are not stacked in our favor our I’m afraid...fingers crossed for a stonking set of 12zs 

Edited November 22, 2019 by Tim Bland

[SMU]

25 minutes ago, frosty ground said:

Not sure what else I can say..........

The output of the 06 Op GFS would fit in with the 0z Ensemble GFS output without being an outright outlier.

The entire Suite has moved with the operational, nothing new about that it has happened many countless times before and it has moved back, sometimes it hasn't but what history tells us is you can not throw a run away without seeing its ensembles just because its different..... hence the term more runs needed. 

I think these exchanges are useful for us all.

 

I will add detail & tag you later

 

Edited November 22, 2019 by Blessed Weather
Edited to reflect original post in quote box now edited.

[Jordan S]

This whole debate of what said o'clock run should be binned or not binned seems rather pointless..

Anyway A quick few glances on the Gfs, Gem and Ecm below.

GFS.. 26th

27th..

29th..

1st December..

2nd..

Gem.. 26th

28th..

30th..

1st..

2nd..

Ecm.. 

26th..

28th..

1st December..

2nd..

All three show unsettled conditions upto Thursday detail different as you'd expect for a few days away, the Gfs and Gem both show a fairly deep low pressure system pushing across the UK on Saturday 29th in Sunday 30th..which is then shown to pull into the north sea with a ridge of high pressure toppling over the uk at first bringing a chilly northerly but getting cut off with high pressure now sitting over the country at day 10 pretty similar evolution considering this is a week away but the Ecm is slightly different it does bring low pressure in around the 30th..but high pressure out in the Atlantic is further west and much stronger with ridging towards Greenland bringing in cold northerly winds with showers albeit wintry. 

Anyway back to the shorter term and more reliable time frame. The same as I've said in recent days.. Very unsettled with very wet weather at times with drier weather and sunshine at a premium for most although through this week period northern Scotland may fair best. 

So this afternoon turns drier for most of the UK but still with some showers continuing in places but towards the south and southwest more persistent rain will be pushing in later this afternoon giving a wet evening for southwest and England and Wales elsewhere drier spells but mostly cloudy and fairly windy too. Feeling milder than of late particularly for England and Wales with a southeasterly wind.

For tonight into tomorrow more widespread rain spreading up from France into many southern and central parts of England quite heavy locally particularly still for the southwest and Wales but mostly on the moderate side elsewhere. 

The rain continues to push north to effect southern Scotland and Northern England although northwest Scotland drier with also drier conditions for  England for a time in the morning before a little more rain pushes north or northwest into the south and south east joining forces with the rain further north and west. Drier conditions eventually developing for the south and east by evening. Rain becomes confined to Scotland by tomorrow night. 

Sunday then starts quite wet for parts of Scotland elsewhere mostly dry with some sunshine although a lot of cloud around with the odd few showers around. Winds southeasterly for Scotland and much of England at first  but turning southerly as the next frontal system pushes in to the far west by evening.. 

This then brings a wet night for Sunday night into much of Monday for most parts with heavy rain in places.. This eventually clearing into more showery areas of rain by Monday afternoon.. 

Later Monday many places drier but a band of rain stretching through Wales and central England bringing more prolonged rainfall.. 

Tuesday morning for the majority may be drier until the afternoon with more heavy rain and windy conditions spreading across the country this most focused for England and Wales once again pivoting so that some rain also gets into northern Ireland. Winds from the southwest. But southeast for Scotland.  The rain then becomes confined to much of Scotland giving a very wet Wednesday there but for northern England and Northern Ireland also southern parts of England and Wales turning drier again until perhaps more rain from a wrapped around weather front in association with the centre of low pressure pushing through southern counties by Wednesday morning. 

Thursday then a drier day for Many parts with some showery rain for Eastern Scotland. 

That drier interlude perhaps not lasting long because by Friday morning more perhaps very heavy rain pushing into the west accompanied by strong winds from the south and southwest this spreading across the majority through the day but with again northern Scotland perhaps missing out with drier conditions there..

An animation below of the ensemble mean upper air temperatures for the next 10 days from the GEFS latest output if you look closely you can see little ripples moving across the Atlantic towards the UK at frequent intervals this denoting areas of low pressure. Mostly mild too but with perhaps a colder interlude near day 10.. A very unsettled pattern though.

A summary animation chart for the weather over the next 10 days below..

GFS rainfall accumulation forecast for the next 10 days below too.. 

Gem rainfall accumulation too..

More updates coming later.

Edited November 22, 2019 by jordan smith

[Weathizard]

4 minutes ago, Tim Bland said:

GFS op disagreements aside it is more concerning for me that MOGREPS only sees this as a transient cold spell, most EPS clusters and GEFS (ensembles) agree (19/20) Meteogroup (BBC forecast earlier) said brief cold spell end of next week and they have more output to digest and come to this forecast than us. Will be interesting to see the meto long range update shortly.  Still time for change and all the models are just forecasts, but odds are not stacked in our favor our I’m afraid...fingers crossed for a stonking set of 12zs 

The MOGREPS are equally as fallible as any other model really though aren’t they, last winter has scarred me I mean the Met further outlook said cold to very cold from the east for about 2 months and it never truly materialised, which must mean the mogreps were just as wrong.

One day technology will advance far enough that weather predictions can be absolutely exact, until that day I think particularly outside of a 5/6 day range the UK will remain a minefield, I mean let’s be honest no models are particularly reliable once you get past that 5/6 day region, partly due to our location.

[knocker]

The ext anomalies this morning were in the same ball park but the GEFS had th NH pattern a tad further east which obviously will make a difference regarding the evolution of the detail so needs to be resolved. Await this evening with some interest