Model Output Discussion 13/11/13 >

[Summer Sun]

A few minutes ago I talked about the high to our south west possibly forcing the low across Greenland erasing the northern blocking and here it is

 

 

Cold for some but becoming less cold from the west

 

Edited November 15, 2013 by Summer Sun

[Cheshire Freeze]

Day 10 we lose the heights to the N but I'm guessing there will be many more twists and turns to await us in the next few days

 

[snowangel32]

Its obvious to my untrained eye that the models are having a nightmare predicting what is going to happen with the short waves and until it is resolved they will keep flipping back and forth as today has showed i expect further changes good or bad who knows, its going to be a bumpy ride, fasten your seat belts lol

[syed2878]

it's like i said last night we should hold on to our horses before we recall 2010 how ever interesting forecast by the met for next 2weeks or so.

[MR EXTREMES]

yes snowman im serious but by no means mild.

but I will hold out from making anymore second guessing fi model runs because im on the fence for December but theres nothing in the model outputs that showed anything like lastnight infact this is the most dramatic turn around ive seen for sometime.

 

but if I was going to have a punt it would be cool settled next week unsettled later in the week with low pressure systems moving in from the west but possibly settled again as azore high pressure moves in beyond that I ask mystic meg.

 

now ive seen the last frame of the ecm settled for a short time then back to unsettled never above average temp wise and as steve suggest cold surface temps if models are right with there outputs.

 

and sorry yes December 2010.

Edited November 15, 2013 by model rollercoaster

[Joe Levy]

If anything, the fact that the models keep changing is reassuring, as it shows that a pattern shift is under way, whatever that may be. I suppose it's quite fun to think of all the different runs and charts as parallel universes! The further out from the present you go, the more vastly different the options become, because small differences now mean big changes later! It is these small differences that are currently evolving that are giving us and the models a headache!

[Cecil Hogmanay Melchett]

Day 10 looks poor for coldies but at 240h im not be worrying about it..

[swfc]

If anything, the fact that the models keep changing is reassuring, as it shows that a pattern shift is under way, whatever that may be. I suppose it's quite fun to think of all the different runs and charts as parallel universes! The further out from the present you go, the more vastly different the options become, because small differences now mean big changes later! It is these small differences that are currently evolving that are giving us and the models a headache!

Sounds just like my wife!!!  Good point tho joe

[Methuselah]

Everyone please note: bandwidth is not infinite; silly posts of one word + a smiley are not ideal...at least when they're more frequent than snow drifts...

[shedhead]

All the big 3 show reasonably similar synoptics now at 144hrs. Gone is the very wintry setup touted by both GFS and ECM across the last 24hrs, but none of these charts are remotely mild, in fact many place will be cold or even very cold for the time of year IF they verify. 

 

Given the swing we've seen in the outputs across the last 24hrs I see no point in posting T192hr and T+216hr charts just because they show another possible return to cold, especially as future HLB looks further away now than it has for some time. 

 

 

ECM

 

UKMO

GFS

 

Edited November 15, 2013 by shedhead

[Joe Levy]

Sounds just like my wife!!!  Good point tho joe

Thanks... I think I've never been compared to anyone's wife before! 

[shotski]

I think we need to look at the long range anomaly charts for a clearer picture in the

next couple of weeks NOAA and JMA both say no to a return of anything zonal and

still show a blocked picture, Mid latitude at least.

 

Shotski

[Tamara]

And more to the point it's T+192hrs again... just remember how things looked at +144hrs only 24hrs ago.  The carrot and stick avatar looks about right.

I'm not sure that the expectations up to midweek next week have suggested anything more than an atlantic ridge at any time - only the degree of amplification has been open to question in this respect. There is no-one on here or even at the METO that precisely can measure or prophesy how exact jet energy equations in a split flow scenario are going to impact on this tiny island which sits in what is a very large NH on the macro scale. 

 

Therefore any carrot and stick analogy is redundantly void and impotent.

 

Assuming that the day 4 to 6 period is coming into some king of agreement - and with that said, it can actually be argued in terms of tonights model suggestions (overall) that there is still room for adjustment which just as conceivably might involve a small amount of amplification adjustment increase (as the pendulum swings back just a little once again) as any flatter solution.

 

On this basis, the evolution from midweek to a second possibly more southward and westward advancing cold air advection is completely within bounds and attuned to the METO further outlook suggestions of pressure higher to the north and lower over the nearby continent in the latter part of this month. Unless anyone on here claims to have further current data to claim otherwise

[Purga]

So the ECM signals the end of a short lived cold snap

 

See what 0z brings then.

[Severe Siberian icy blast]

I'm not sure that the expectations up to midweek next week have suggested anything more than an atlantic ridge at any time - only the degree of amplification has been open to question in this respect. There is no-one on here or even at the METO that precisely can measure or prophesy how exact jet energy equations in a split flow scenario are going to impact on this tiny island which sits in what is a very large NH on the macro scale.  Therefore any carrot and stick analogy is redundantly void and impotent. Assuming that the day 4 to 6 period is coming into some king of agreement - and with that said, it can actually be argued in terms of tonights model suggestions (overall) that there is still room for adjustment which just as conceivably might involve a small amount of amplification adjustment increase (as the pendulum swings back just a little once again) as any flatter solution. On this basis, the evolution from midweek to a second possibly more southward and westward advancing cold air advection is completely within bounds and attuned to the METO further outlook suggestions of pressure higher to the north and lower over the nearby continent in the latter part of this month. Unless anyone on here claims to have further current data to claim otherwise

I couldn't agree more .What makes me astonished more than the models tonight is how everybody on hear so completely waving this cold spell good bye after one bad run of models, yes they are all singing on the same hyme sheet but no different to the astonishing charts they all chucked out together this last 3 days or so. Is not quite possible that they will look completely different again in the morning? Iv just read a comment in the winter thread now claiming unless we have big strat changes in next few weeks (they obviously have no idea on what's been said today in the strat thread) then we can wave good bye to December. I have never read so much rubbish . What makes the charts any more right tonight than what they was yesterday? I fail to understand why people do this evey single year .All we no is it's getting cold. And staying cold.The professionals are talking of the possibility of prolonged cold, why the hell Ian would the bbc change there forecasts after ONE set of runs?

[Team Jo]

Sorry folks, but point scoring/digging etc doesn't belong in here.

 

If you want to vent your frustration at tonights run, then by all means, read the chart analysis in here, but please type your frustration in the Ramp thread. 

 

Ta!

[Summer Sun]

Latest on the models from Gibby

 

All models show a slack flow over the UK with a ridge of High pressure lying across Central regions. To the SE of it some clear skies allow frost and fog to form tonight while the North, on the other side of the ridge see cloudier, milder Westerly winds but mostly dry weather. With time over the weekend the cloudier weather in the NW wins out covering all areas by Sunday. At that time a trough sinking South over the UK could bring some rain to many areas as it moves North to South through the day. On Monday a more active feature sinks South too with a cold NW flow with scattered wintry showers following mostly over Northern and Western areas on Tuesday.

 

GFS then keeps things rather cold and showery for a time through the middle of next week with some snowfall over the hills before High pressure develops over the UK with frost and freezing fog likely to become a major problem later in the week as pressure builds across from the Atlantic. Later in the run details are irrelevant but the trend shows Low pressure gradually taking control from the SW with rain at times in rather cold conditions but snow only likely on high ground in more Northern Britain. It looks like it will stay quite chilly feeling though.

 

UKMO shows High pressure building quickly over the UK later next week following Low pressure moving away South from Southern Britain midweek. Rain and wintry showers will affect Southern areas for a time midweek with snow on the higher hills briefly. Temperatures would be cold everywhere and particularly in the High pressure area later in the week frost and freezing fog will become a big issue, difficult to shift through the days.

 

GEM shows a cold NW, North then NE flow next week and while it will never be cold enough for snow generally it will feel cold enough in a raw wind with sunshine and wintry showers, especially in the North at first and the South and East later. Pressure becomes very high to the NW and with a serious injection of cold air approaching Eastern areas at the end of the run possibly grazing the SE for a time.

 

NAVGEM maintains High pressure to the North and then West as we move through next week with the innitial North flow with wintry showers quickly turning North-easterly across the South with rain or sleet at times briefly. Late in the run winds back Northerly again as the cold theme continues with some wintry showers in the North and East a week from now.

 

ECM tonight shows a chilly NW flow with showers, wintry on hills in the North and West. Soon after midweek High pressure builds in killing the showers and cold wind and a frosty and potentially foggy spell develops as the High sits over the South of the UK.As it moves slowly East late in the run a small Low sinks SE down to the SW with dull and damp weather likely for a time while others stay misty or foggy and cold. The NW would see milder SW winds encroaching by Day 10 as the Jet Stream rides North with Greenland Low pressure developing.  

 

The GFS Ensembles tonight show a short cold snap before the general average of members suggest a milder trend from the mid and end sections of the run. Average level temperatures are then popularly shown with rain at times as the Atlantic gradually regains momentum.The Jet Stream tonight blows across the North for the next day or so before buckling South as the weather turns colder early next week. Longer term tonight the Northern arm of the Jet appears to remain stronger than on recent outputs and carries East across the Atlantic and across the UK in a week or so time.

 

In Summary tonight there has been a cross the board downgrade today if it's snow you are after, not that away from higher ground in the North it ever looked like a major problem to be brutally honest. However, High pressure over the UK is likely to promote colder temperatures at the surface with sharp frosts and freezing fog much more likely to feature next week now rather than sleet and snow. It's seems the behavior and the track of the Jet flow has changed in it's more up to date projections with a UK based Jet flow shown after next week instead of being at a point South of the UK being shown yesterday. The net result looks like a period of UK high pressure giving fog and frost but with little high level blocking in evidence tonight from GFS and ECM it looks like a steady road towards the Atlantic train before too long.

 

http://www.norton-radstockweather.co.uk/Model-Analysis%282859336%29.htm

[gottolovethisweather]

Sorry folks, but point scoring/digging etc doesn't belong in here.

 

If you want to vent your frustration at tonights run, then by all means, read the chart analysis in here, but please type your frustration in the Ramp thread. 

 

Ta!

 

When there is some.  

[shedhead]

I'm not sure that the expectations up to midweek next week have suggested anything more than an atlantic ridge at any time - only the degree of amplification has been open to question in this respect. There is no-one on here or even at the METO that precisely can measure or prophesy how exact jet energy equations in a split flow scenario are going to impact on this tiny island which sits in what is a very large NH on the macro scale. 

 

Therefore any carrot and stick analogy is redundantly void and impotent.

 

Assuming that the day 4 to 6 period is coming into some king of agreement - and with that said, it can actually be argued in terms of tonights model suggestions (overall) that there is still room for adjustment which just as conceivably might involve a small amount of amplification adjustment increase (as the pendulum swings back just a little once again) as any flatter solution.

 

On this basis, the evolution from midweek to a second possibly more southward and westward advancing cold air advection is completely within bounds and attuned to the METO further outlook suggestions of pressure higher to the north and lower over the nearby continent in the latter part of this month. Unless anyone on here claims to have further current data to claim otherwise

Therefore any carrot and stick analogy is redundantly void and impotent.

 

I kinda think you missed the point I was making at the time, which was if you keep looking to 192 and 216hr charts for hope as Steve was at that time, it very much matched his carrot and stick avatar.

[ANYWEATHER]

For Heaven sake!!  One day of model output which is not so good as yesterdays charts is very normal in my opinion! Models will flip too and fro. The cold charts really are some special for this time of year. Take no notice of precip charts this far out either, they will certainly change along with the whole complete detailed synoptic situation offered from the models at present. The cold is coming and we will have to dot the eyes and cross the teas very much nearer the time. Just think back to the 1990,s for the generally lack of Winter weather nationwide,, if we were offered this synoptic scenario even in the middle of January back then ,I certainly would of been very happy to see this! Times have changed, The benchmark was 2007 , since then Winter charts are now commonplace...

[damianslaw]

Notable changes in the models from one day to the next within the 144hr timeframe is always an indication they are struggling.

 

In these situations best to stick to the 96-120 hr timeframe and expect further changes in the 144hr outputs +. There are too many variables and possibilities at present when predicting the medium term, and developments in the short term will have a major bearing...

 

One thing the models all agree on is a pattern change to much colder conditions, with chance of snow on low ground in the north by Wednesday.

 

We have a very messy situation. One thing that is also about to occur is some proper cold pooling to our NE which has been absent in recent weeks, a weakened PV will have a much tougher fight to make inroads into scandi as a result increasing the chance of a southerly tracking jet with us on the cold side.

[gottolovethisweather]

Therefore any carrot and stick analogy is redundantly void and impotent.

 

I kinda think you missed the point I was making at the time, which was if you keep looking to 192 and 216hr charts for hope as Steve was at that time, it very much matched his carrot and stick avatar.

 

Shed, come on and the same applies to others. Please read your friendly moderator's postings above. Best we all chill now before the pub runs come out and then we can either drown our sorrows simply because a couple of consecutive failed runs or look have a wider perspective and say hell, there's always next time.

Edited November 15, 2013 by gottolovethisweather

[nick sussex]

Confusion reigns this evening across the models. I think what we might be seeing is the models catching up to a background signal to move the PV and the operationals were slow to pick up on this and some  flattening of the upstream pattern.

 

It's obvious that model reliability will be impacted by the PV movement and so its difficult to hang your hat on any of the solutions shown by the models past 144hrs. Although the big 3 look to have a similar trend we can't even be sure at this stage how wintry or not this cold snap will be, the UKMO brings down a shortwave which could deliver some snow depending on location and whether we see  a warm sector and how deep this feature becomes.

 

By far the best output from a cold perspective is the UKMO which has enough energy running under the high and has this further north, the GFS looked like it was going to sink the high but in a plot line out of Flash Gordon the imminent demise of our hero found the suitable ledge over the cliff, the GFS lands because low heights over the northern Med stop the jet from delivering a  fatal blow!

 

The ECM is similar in pattern to this morning but looks fraught with danger again low heights to the south save the day, it then goes onto to deliver some interest with a ridge over Greenland, but the axis of any low pressure to the west even if it has the trend correct is subject to change, it doesn't take a fiction writer to see how that could develop more favourably if you're a coldie but again too far out and seeing as the models were off with the jet within T120hrs then hardly a scenario to have too much confidence in.

 

I think it's a case of sitting and watching the drama unfold, I'm sure theres more to come in the coming days.

[Joe Levy]

I think we need to look at the long range anomaly charts for a clearer picture in the

next couple of weeks NOAA and JMA both say no to a return of anything zonal and

still show a blocked picture, Mid latitude at least.

 

Shotski

See this sort of thinking is exactly what is needed! Long term trends carry more value than small details when we are looking at anything after t72. We can start looking for wintry specifics when we get nearer to the time, but right now things are heading in the right direction. But that depends how impatient we are!

[Catacol]

Regardless of specifics, which are nigh on impossible to predict, it is the re-occurrence of charts like this that explain my optimism. Clearly the models want high pressure to form somewhere in the North Atlantic, reflected in the height anomaly charts. It's where exactly that makes the difference. The issue is that tiny details can overcomplicate matters and so this is why trend spotting is a more intelligent idea rather than losing all sense of reality every time a chart is not so good for cold, or equally if it is fantastic for cold. We must use our heads and our experience! 

 

Wise words. Over the years many on here get wrapped up in too much detail run to run. We must step back and take an overview here - back at the start of November many were calling for a pretty flat pattern through until December. I called the same myself though I saw it more of a NW than W pattern and wasnt sure where the meto call of an above average November was coming from. IB used the word "zonal" about 4 times in one night, calling it game over for the month.

 

Where are we now? Details aside the whole global circulation pattern is much more meridional than many expected, and we have blocking in both the atlantic and pacific sectors that is giving the vortex a hard time. Suddenly we are not seeing low pressure firing out of Canada and there is a sense of a stalling atlantic pattern in the air. Final juicy mouthful is the meto update which is clearly an upgrade in terms of snow potential.

 

Enjoy the ride, but dont get stuck on detail. And revel in the fact that many people, including myself, may well have misjudged the next 4 - 5 weeks. As ever time will tell. It's only Nov 15 and I dont think realistically think we could have hoped for much better when you recall where we were 2 - 3 weeks ago. Just to remind you how it was only 12 days ago!

 

Edited November 15, 2013 by Catacol_Highlander