Model Output Discussion - 05/01/2016 18z onwards

[Shuga ice]

This was how I saw it playing out yesterday.   The  overnight charts have moved away from the colder charts of a couple of days ago.  We are looking at a cool dry interlude but with some transitional snow in favoured spots before rain spreads from the west.  Met office aren't all that good either, they have to sit on the fence for as long as possible due to going public, but holding back does give the effect of them knowing better than others, simply not true.

Edited January 8, 2016 by Osbourne One-Nil
Now now.

[winterof79]

A lot of self induced panic this morning. I see cold and snow for next week.The models are showing a difficult breakdown as the met allude to.As I said yesterday the cold/scandi trough will be back in at any opportunity.

[Severe Siberian icy blast]

I'm sorry but this place is so predictable.  The very first words I look at is "this is a very depressing morning "

is it really ? 

Firstly its only depressing if you allow yourself to be taken in by every signal model , 

secondly what makes charts after t120 any more likely to come off than they showed yesterday , or the day before that ? 

We still have a cold spell on , ok not freezing cold next week like everyone was hoping , still cold enough for snow , which is enough for me .

i didn't believe for one minute we would be basking in -10 850's , it's been a developing situation and it still is . The models will play around with different outcomes until they get it right , and they won't get it right until inside t72 with this type of scenario .

just enjoy the ride and don't get depressed every time the models change.

Edited January 8, 2016 by Severe Siberian icy blast

[The PIT]

2 minutes ago, winterof79 said:

A lot of self induced panic this morning. I see cold and snow for next week.The models are showing a difficult breakdown as the met allude to.As I said yesterday the cold/scandi trough will be back in at any opportunity.

No induced panic just a realization that there's a drift towards a less cold solution than previously shown. Both GFS and ECM are delaying the introduction of cold air. This has always been a bad sign in the past though.

[Mair Snaw]

1 minute ago, winterof79 said:

A lot of self induced panic this morning. I see cold and snow for next week.The models are showing a difficult breakdown as the met allude to.As I said yesterday the cold/scandi trough will be back in at any opportunity.

Could not agree more with this... many are talking like this low pressure is nailed on to take the track shown this morning, when in reality we all know that the track of this low will change right up until t12 or even t6.... its happened so many times in the past and will happen this time round we will spend the next week seeing different tracks played out and 200 miles further north  or south will have massive changes on what follows... just last month the Midlands was in a yellow warning of Snow and just 12 hours later when the front came in it was further north and friends in Newcastle got the snow... so fine details are never certain...

[Radiating Dendrite]

It's not really a breakdown though as we never actually go into the freezer.

All we see is a chilly spell with night frosts and +4/5 by day in the South. Then the low moves in from the South West bringing a snow to rain event for the North while in the south we go back to just boring wet.

The wild swings imply that no model has the right idea yet.....they always struggle with what is a very complex set up. It will me a million times different at day 10 to what is shown now. 

[rory o gorman]

9 minutes ago, Severe Siberian icy blast said:

I'm sorry but this place is so predictable.  The very first words I look at is "this is a very depressing morning "

is it really ? 

Firstly its only depressing if you allow yourself to be taken in by every signal model , 

secondl m what makes charts after t120 any more likely to be to come off than they showed yesterday , or the day before that ? 

We still have a cold spell on , ok not freezing cold next week like everyone was hoping , still cold enough for snow , which is enough for me .

i didn't believe for one minute we would be basking in -10 850's , it's been a developing situation and it still is . The models will play around with different outcomes until they get it right , and they won't get it right until inside t72 with this type of scenario .

just enjoy the ride and don't get depressed every time the models change.

Very bias post I'm afraid. The gfs is consistent now in it's output , with the ECM backing the evolution this morning.    

 

Edited January 8, 2016 by Osbourne One-Nil
No need for the last sentence!

[cyclonic happiness]

3 minutes ago, Radiating Dendrite said:

It's not really a breakdown though as we never actually go into the freezer.

All we see is a chilly spell with night frosts and +4/5 by day in the South. Then the low moves in from the South West bringing a snow to rain event for the North while in the south we go back to just boring wet.

The wild swings imply that no model has the right idea yet.....they always struggle with what is a very complex set up. It will me a million times different at day 10 to what is shown now. 

We'll probably have the frosts downgraded over the next few runs too, not a chance of snow for where I live, the weather gods have already decided that. I'm gonna get some tee-shirts printed for Netweather "All I need is frost' written on them 

[Kentish Snowman in Yorks]

6 minutes ago, rory o gorman said:

Very bias post I'm afraid. The gfs is consistent now in it's output , with the ECM backing the evolution this morning.    

 

You mean the ops are consistent?  I believe Bluearmy has already stated that the parallel runs of both the ECM and GFS have trended colder than yesterday?

The GFS ensembles are not fantastic if it is cold weather you like but they are certainly not poor either with a number of perturbations keeping us in the freezer right out to the end of week two.

As for the ECM well we don't know where it sits within the ensembles yet although my money is on it being a mild outlier.

Anyway even if the doom mongers are correct and all everybody gets out of this upcoming spell is cold rain then so be it.  It is only the weather after all!

[TEITS]

8 minutes ago, rory o gorman said:

Very bias post I'm afraid. The gfs is consistent now in it's output , with the ECM backing the evolution this morning.    

 

That certainly isn't the case with the GEFS ensembles. From the 17th Jan we see a difference of almost 20C!!

When you have such a massive difference between the models i.e UKMO vs GFS/ECM then experience tells me not make any assumptions and just wait until the models agree.

 

[Mair Snaw]

1 minute ago, TEITS said:

That certainly isn't the case with the GEFS ensembles. From the 17th Jan we see a difference of almost 20C!!

When you have such a massive difference between the models i.e UKMO vs GFS/ECM then experience tells me not make any assumptions and just wait until the models agree.

 

Good to see you posting again TEITS.....

[snowprincesspboro]

hi all, hope your all well, been keeping tabs on whats happening in here for a few weeks now, reading through all your fantastic posts, but im starting to get very confused, i like to read through but cant say i completely understand everything posted on here haha. dont know if its just me but it seems the cold has been kept in fI for quite some time up until the past few days when it has slowly started to arrive in a reliable (ish) timeframe, but the part that confuses me is that the majority of posters are constantly searching for the 'deep in the freezer, 62/63 type snowmageddon' (dont shoot me i do understand this is a weather forum) and i cant get heads or tails of if these 'downgrades/bad solutions' are for the apocalyptic solution most seem to be searching for, or for the good enough chance of having a bit of laying snow situation.

hopefully im not alone in the thought that with the past couple of winters weve been put through, and that god-awful spring-like december weve all just endured, that a cold 'snap' with the chance of a couple of cms of laying snow, would be an extremily better outcome than a carry on of this so called 'winter' so far. 

if ok for us less knowledgeable few please can someone just do a quick update on if theres gonna be cold soon with any chance of snow? im not asking for an imby snow description, just whats the plan for the next few days, snowmageddon would be amazing, my daughters wouldnt know what to do, me neither really haha but the confusing bit for me is with so many searching for the most unrealistic hardest to get solution for any given winter, are we missing (not discussing) a nice normal cold snap with snow chances thats right under our nose, or is even the smallest chance of that disappearing?

sorry for all the questions and if its not making sense, i know what im trying to say haha , think i really need to learn more so i can do this for myself xx

[cyclonic happiness]

I really, really hope this is a wobble, whether it's objective or not, we 'need' a snow event or two, some of us won't have seen snow for three years in March, that is a truly depressing thought.

I'm starting to wonder whether the weather is being manipulated in favour of another country? 

[joggs]

2 minutes ago, TEITS said:

That certainly isn't the case with the GEFS ensembles. From the 17th Jan we see a difference of almost 20C!!

When you have such a massive difference between the models i.e UKMO vs GFS/ECM then experience tells me not make any assumptions and just wait until the models agree.

 

Missed you on here teits.Your input and reasoning to where you think we're headed(right or wrong)is greatly appreciated.Just for the record,how dya think this will pan out?

[rory o gorman]

1 minute ago, Kentish Snowman said:

You mean the ops are consistent?  I believe Bluearmy has already stated that the parallel runs of both the ECM and GFS have trended colder than yesterday?

The GFS ensembles are not fantastic if it is cold weather you like but they are certainly not poor either with a number of perturbations keeping us in the freezer right out to the end of week two.

As for the ECM well we don't know where it sits within the ensembles yet although my money is on it being a mild outlier.

Anyway even if the doom mongers are correct and all everybody gets out of this upcoming spell is cold rain then so be it.  It is only the weather after all!

Control backs the OP in both runs , but yes there are wild fluctuations some of which are backing prolonged cold . Taking some perspect almost all 21 members were depicting  cold this time yesterday today is less than half . This is a downgrade as much as anyone may want to spin it. The rapid increase in the subtropical jet as a result of cut off heights is a credible solution that has been seen many times before.  Just looking at this objectively and without bias. 

[bluearmy]

1 minute ago, Kentish Snowman said:

You mean the ops are consistent?  I believe Bluearmy has already stated that the parallel runs of both the ECM and GFS have trended colder than yesterday?

The GFS ensembles are not fantastic if it is cold weather you like but they are certainly not poor either with a number of perturbations keeping us in the freezer right out to the end of week two.

As for the ECM well we don't know where it sits within the ensembles yet although my money is on it being a mild outlier.

Anyway even if the doom mongers are correct and all everybody gets out of this upcoming spell is cold rain then so be it.  It is only the weather after all!

 

Sorry but the parallel ops are leading the way on the west based NAO and low upper cold not embedding so strongly beforehand.  Due to the Atlantic trough hanging back for too long. the most recent runs less favourable for lasting cold than the previous.  However, this is a snapshot in time and must be viewed as such. The ens give us an envelope to work within and the pendulum can just as easily swing back somewhat through the next few op runs.  tbh, we know the unreliability of ops post day 6. 

this is is a tricky evolution with the polar high and n American trough both of paramount importance in how plays out.  We should see the way forward with some reliability over the weekend. if we arrive at the 20th without a decent snow event on low ground somewhere over the UK then it will be a big surprise. 

[Harsh Climate]

Any chance that that ECM is an outliar or on the milder side of it's esembles? Whether this morning is a downgrade or not depends on that really.

UKMO and GFS Esembles are great this morning, ECM badly lets us down. A good set of ECM esembles and that changes everything.

[Harsh Climate]

But as bad as the ECM looks on face value after the great charts we've been spoilt with really, under normal circumstances this mornings ECM run shouldn't be scoffed at:

 

Chances of snow in northern areas at day 6 and 9

Yes at that range all relative.

[offerman]

I have never seen such a large and stuborn mediteranean high such as the one we have had all winter so far. Unfortunately this high looks like reforming in the med to throw up more mild and unsettled southwesterlies thus pushing the cold back far quicker than we all expected. 

[jgbgt]

7 minutes ago, rory o gorman said:

Control backs the OP in both runs , but yes there are wild fluctuations some of which are backing prolonged cold . Taking some perspect almost all 21 members were depicting  cold this time yesterday today is less than half . This is a downgrade as much as anyone may want to spin it. The rapid increase in the subtropical jet as a result of cut off heights is a credible solution that has been seen many times before.  Just looking at this objectively and without bias. 

I count 5 members at 17/18th above the mean which still looks fairly cold to me. Bearing in mind the mean is screwed itself by the other not clustered  solutions the probability is still for colder in my eyes. 

Yes op and control are higher res, but from low res points both deviate from the mean quite drastically. (Pretty much the definition of an outlier)

jg

 

 

Edited January 8, 2016 by jgbgt

[blizzard81]

18 minutes ago, TEITS said:

That certainly isn't the case with the GEFS ensembles. From the 17th Jan we see a difference of almost 20C!!

When you have such a massive difference between the models i.e UKMO vs GFS/ECM then experience tells me not make any assumptions and just wait until the models agree.

 

Great to have you back TEITS

[That ECM]

As good as the output has been and still is to a certain extent there has been the meto longer term updates which were of a concern. When you looked, the output,they were suggesting cold for a spell yet never did we see that in their commentary. " uncertainty" was as close as we got.

 

lesson for newbies is as ever, anything past t120 is for fun. Cross model agreement backed by meto thoughts is great but still no guarantee.

 

so where we are now is in the land of uncertainty as ukmo is different. I think that much is to be resolved with all options in play. 

Edited January 8, 2016 by That ECM

[IDO]

The problem was that sustained WAA was needed to keep the meridional flow. When this pattern change occured you have to ignore the early op runs as all models tend to over do heights (and therefore WAA). Once they settle into the change the models were downgrading run on run the WAA pumped into the EPO and Atlantic Ridge. We were therefore left with wedges of high latitude surface highs within a slow moving mobile system unable to sustain a block in one locale. The Atlantic Ridge (GH) has more longevity due to the Azores upper low undercut (so teased us for a while) as it supported that wedge, but that Low was caught in the jet, and once the wedge of Greenland high pressure meandered towards the Pacific the upper low/jet could re establish further north and redirect over the UK.

The EPO block was from the MJO signal but there is no further wave coming into the mix, and no sign yet of the ~torpedo~ that would have the same effect. If the experts are right this should change the FI charts in the next 5-7 days model watching. 

The question is now that the models have got to grips with the fact that were over amplifying, have they over done the correction? Hopefully they have and we will move to a slightly better scenario than the 0z models are showing. 

GFS was the first to spot the cut off upper low and the first to see that as a trigger to cut off the heights, ECM was next and UKMO as per usual are trailing a day behind at T144, as is their will when it comes to signals in high entropy situations. You can see the UKMO 0z pumping warmer air north in the Atlantic ridge on this morning's run (yellows, where they are greens for GFS) despite a sea change yesterday by the GFS and ensembles to cut off that warmth. now replicated this morning by ECM and GEM. I would be surprised if the UKMO is correct.

Neither CFS or JMA are offering any longevity (w3 and w4) to this cold spell and I suspect that is the same with the UKMO products we don't see. We need a background signal to amplify the flow again and the trend has been the opposite in that crucial D5-D8 period for the Atlantic and Pacific regions (upstream). It's not a missed opportunity, it is the model bias to pattern changes, their ~boom~ charts were just wrong.

JMA & CFS w3 & w4: 

 

[blizzard81]

Just now, That ECM said:

As good as the output has been and still is to a certain extent there has been the meto longer term updates which were of a concern. When you looked they were suggesting cold for a spell yet never did we see that in their commentary. " uncertainty" was as close as we got.

 

lesson for newbies is as ever, anything past t120 is for fun. Cross model agreement backed by meto thoughts is great but still no guarantee.

 

so where we are now is in the land of uncertainty as ukmo is different. I think that much is to be resolved with all options in play. 

I agree. If this does indeed downgrade, imense credit must be given to mogreps. 

[rory o gorman]

21 minutes ago, jgbgt said:

I count 5 members at 17/18th above the mean which still looks fairly cold to me. Bearing in mind the mean is screwed itself by the older solutions the probability is still for colder in my eyes. 

Yes op and control are higher res, but from low res points both deviate from the mean quite drastically. (Pretty much the definition of an outlier)

jg

 

 

I don't really understand your point here? There is a clear shift in the ens pack to a broad number of outcomes. It doesn't mean that the chance of prolonged cold is finished , just that there are some plausible solutions which result in a mobile pattern being obtained. 24 hours ago it was as close to locked in as possible,  in the timeframe with classic WAA to greenland and possible cross polar flow and rapidly deepening full-neg tilted trough pulling east . So this uncertainty is  unfortunately classed as a downgrade. 

Edited January 8, 2016 by rory o gorman