Model Output Discussion 19th January 2014-18z onwards.

[Long haul to mild]

The models have generally been too progressive with breaking the block down this week, so there is no reason to believe that they won't suffer the same problem for the middle of next week.

The ECM tonight dies a bit of a death at T168 and, as others have said, it looks odd and I suspect that the Westerlies that follow in the latter stages of the run are being overcooked again.

However, it was interesting to see that next week's LP fizzles out over the top of us on the JMA too, so it's something to watch.

It really is very hard to trust the model output at present, with so many swings, so to me any calls for a markedly zonal outlook are premature. If (and I stress IF) the cold does get in next week, I doubt it will just get swept away that quickly, it rarely does in the setups.

[bluearmy]

Ecm op looks like it has some support on the spreads but the anomolys and mean retain the trough dropping into europe. Nothing much changing and the mean day 10 shows an even lower thickness lobe of the vortex extending towards the nw of the uk, much as the extended ecm ens have been showing.

[Staffordshire]

And therein lies the problem - yet a snowless winter is indeed a rare beast so one assumes, as your signature says, the weather will repay its debts. Certainly the rain account is swelling at the moment - the snow account is massively overdrawn...

indeed very rare to see a snowless winter, yes The weather will always pay it's debt, but I can't help but feel it is repaying us in mildness to counter the last few winters, maybe the next couple of summers will be like the one we just had to repay us for the past washout summers.... Who knows, that is what is exciting about the weather and model watching, no one knows what the weather will be like, or what the models will show, sure we can have a good go at trying to predict it but at the end of the day Mother Nature does what it wants we just try and find out what that is before it occurs.

[Stuie]

Good evening. Here is the report from the 12 midday outputs of GFS, UKMO, GEM, NAVGEM and ECM for today Tuesday January 21st 2014. All models show an unsettled and changeable period between now and the start of next week. A band of rain is shown to be currently crossing the UK with clearer and more showery weather following on behind. Tomorrow will see the front bringing the rain only slowly clearing away East out into the North Sea with the rain clearing slowly. Elsewhere a showery West or NW flow blows with showers forming in organized bands both tomorrow and Thursday. By Friday a new trough delivers more appreciable wind and rain through the day and this will be repeated on Sunday with Saturday being the best of the weekend days with sunshine and showers most likely. Throughout this period temperatures will be up and down but never overly cold or mild over the period. GFS tonight then shows next week and indeed beyond unsettled and occasionally windy with showers and longer spells of rain continuing in generally West or NW winds with a few brief Northerly incursions for some pepping up the potential for wintry showers at times but never substantial away from the high ground of the North. The GFS Ensembles are nothing exceptional tonight whatever your preferences should be with plenty of unsettled weather with rain at times blown in on pressure systems crossing the Atlantic and reaching the UK via the West or NW. Temperatures look a smidgen below average overall sufficiently enough for some snow on high ground of the North at times but generally of little consequence. UKMO starts the new week off with deep Low pressure moving ESE towards Scotland with a cool and showery WNW flow over the UK with some heavy showers perhaps with hail and thunder and snow over high ground in the North. GEM shows the Low over Scotland next Monday sinking South over the UK and down into Europe with cold and showery weather with some hill snow at times. Late in the run continuing changeable weather seems likely as further troughs move across from the West and NW with more rain and temperatures returning to average. NAVGEM pushes complex Low pressure out to the NW on Monday South over the UK with showers and longer spells of rain continuing well into the middle of next week. ECM also continues changeable weather through next week with rain or showers at times, probably heavy and persistent at first but with increasingly lengthy drier periods between the rain bands later in the week as the slightly chilly conditions revert towards more average temperatures by the end of the run as winds turn Westerly. The ECM 9 and 10 Day Mean Charts which I highly regard when looking at the probabilities of where we will be standing in 9 and 10 Days time have remained rock solid with the current pattern for what seems an age now and tonight's charts are no exception. In 9 or 10 days time it looks like we will still be staring down the barrel of a stand off between High pressure to the NE and SW with the UK lying on the Western periphery of a North Sea trough with continuing spells of rain and showers in West or NW winds and temperatures near or a fraction below average. http://www.wetterzentrale.de/pics/Reem2161.gifhttp://www.wetterzentrale.de/pics/Reem2401.gif The Jet Stream continues to show very little change in trajectory and course over the coming few weeks as it continues to cross the Atlantic before turning South over the UK towards Southern Europe and then East over the Med. The flow does strengthen for a time next week. In Summary there remains little chance of any significant dry weather over the course of the output tonight. There will again be plenty of rain in areas that could well do without it. For those looking for cold weather there seems little sign of that either tonight with the pattern that we have now remaining in situ for some considerable time to come. However, having said that the air that crosses the UK on the rear of exiting depressions could well be cold enough for some snowfall on hills, especially in the North but once more tonight there seems little sign of any meaningful cold and snowfall.

Yet another great write-up Martin. Not sure you get the credit for your efforts. I do think you will have many more likes in Feb.

[DeKust BergenaanZee]

It is fascinating to see the endless variety of weather, always something slightly different, so much so that even the prediction of behavior of a HP block when confronted with a low seems not possible. There must be countless occurrences of lows running into a scandinavian high and one would think it must be by now possible that the supercomputers have figured out the correct algorithms to model the flow more or less reliably, but nature seems always to have another trick up its sleeve.

[Frosty.]

Well I was a right misery guts last night, was very stressed out actually but I feel better tonight, and some of these GEFS 12z perturbations are even better than I feel, some very wintry runs in here, P1 for example being choc full of wintry reloads, and I already mentioned the control run earlier...and it could become wintry in the semi reliable timeframe, so all to play for guys...chin up fellow coldies, the snow and cold rampers association needs you.

[UV-RAY]

A disappointing ECM heralding a return to zonality after a brief flirtation with a colder pattern

 

 

 

Most concern will be with upcoming wet and stormy conditions on top of saturated ground rather than the odd bit of transitory sleet here and there.

 

GFS illustrates well

 

Later on the next system brings this

 

 

 

Not a lasting cold signal at all at the moment just wet, wet, wet.

Much like I alluded to early, cold snaps here and there but until we see favourable synoptics regarding the Strat, much ado about nothing really.

[IDO]

the ecm at day 10 is not like the mean (no euro trough and all the energy has gone ne rather than splitting), nor is it like the 30% cluster on the gefs.  (the gefs has the azores high displaced north and laying across as an mlb) 

 

the ecm 12z op from two days ago was very progressive as per this run and it was an outlier. i suspect this has some support but it not the favoured solution.

 

Hi BA

 

Thanks for that. The clusters for the upper H500 may illustrate my point better:  

 

Compared to ECM D10 op: 

 

I was referring to the synoptic pattern, not exact surface conditions; within that cluster there are variants on that theme, and the theme is what I was suggesting, that is, the UK disconnect with the upper trough, via AH ridging, and how the GEFS also had a cluster going this way. To me that suggested a degree of cross-model support and that it was unlikely to be an outlier, so could not be discarded. It is a possibility and therefore worth discussing. Of course the favorite remains that the trough digs SE, but it is no slam dunk yet, especially looking at the GEFS.

[Severe Siberian icy blast]

Despite the fact it's very similar to the 00z mean ensemble as others have pointed out. Are they (plus the GFS) all unrealistic too? Plus the METO...Btw, I am not trying to make a personal attack here. I just think after a winter of grave disappointment people need to be realistic about what they are seeing. If you check the model thread back in December you'll see plenty of posts convinced that bitter cold is just around the corner and the models have got it wrong...

I'm very realistic about what to expect thankyou. Iv not ramped up cold this winter , Iv been very realistic all winter. Everybody knows this winter has been about patience and still is . The facts are the pattern going forward is very very different to December , I'm not gonna bother to go through everything again , have a look at my previous posts if interested , I was merely commenting on the way the chart pushed the very strong arctic high out the way very very easily , when experience tells me even taking this last week as an example that models time and time again underestimate the block , especially when it's t144 plus . It looked an unrealistic jump from a fairly -AO to a much more positive one . Iv not ramped up a freeze , but I'm a lot more positive than some on hear and certainly don't jump from ecstasy to depression in the matter of 12 hours like some. I know what pattern we're in ,and know how to spot trends and "potential" pattern changes, and taking everything into account I think the next 6 wks is gonna be a lot more entertaining than the last . Edited January 21, 2014 by Severe Siberian icy blast

[winterof79]

http://www.knmi.nl/exp/pluim/Data/pluim_06260_0_12_60.png?1390339432541

 

As BA says top end of its ensembles further out

Edited January 21, 2014 by winterof79

[karlos1983]

lets just remember one thing here, we can get to cold with or without a SSW. If we relied fully on Strat warming to bring cold solely, then because of the time it can take to have an affect at the surface, winter could well be over, but it isn't.

 

I still can't believe some don't think the cold has a chance of coming in the next 10 days, let alone February, look at the charts, it's entirely feasible.frosty has posted just a few of the possible outcomes, they are being modeled, so it *could* happen. I'm not saying mild isn't an option, that would be naive. All to play for.

 

who knows the ever reliable  18z could throw out a BOOM run.

[Gibby]

Yet another great write-up Martin. Not sure you get the credit for your efforts. I do think you will have many more likes in Feb.

Don't post them across to get credits StuieW but just try to offer a balanced perspective from a thread that can become over burdened with posts looking for that elusive snowflake in what has been one of the most fascinating winter seasons that I have followed model wise for years. I know that will go down like a lead balloon for many on here but there really has been some fascinating model output over recent months and there still is plenty on offer on tonight's output.

 

On a separate issue I have noticed that there is a lot of talk about wild swings between models and runs of length which I don't wholeheartedly agree with. Yes there has been the occasional divergence into a more wintry outlook but always in FI and only when viewed from an operational run's viewpoint. The Ensembles which I much prefer to gauge my end summary upon within my reports have maintained a lot of stability in their prediction of a maintained trough near or just to the East of the UK for what seems ages now, particularly ECM. I think people would get a better idea of the most likely outcome in 7-14 days time if they viewed these ensembles rather than get hung up on each individual operational run which shows something mouthwatering and probably off kilter from the rest of the member output..

 

This is not a criticism of anybody and the debate and constructive arguments at times from those more knowledgeable on here make for very interesting reading at the end of a long day and long may it continue. I just sometimes feel that the less knowledgeable can become disorientated by the skewed obsession from a wealth of posters on the one factor of weather which is the most rare in the UK. I agree with Ian Ferguson's earlier post which reflected the more important issues of impending further flooding issues that are likely as long as this current pattern persists rather than searching for snow which is far less likely currently.

 

Finally from me tonight a note of optimism for coldies. Although the evidence for cold is not great at the moment going by tonight's output the building blocks are there to the NE and for those who can think back to my Winter Forecast I suggested then that February offered the best hope for cold and snow this Winter in the UK and that still stands as of now.  

Edited January 21, 2014 by Gibby

[Cloud 10]

Probably the coldest set of ECM long range ensembles of the "winter" so far with 

the mean close to freezing throughout.

 

Also the first appearance of -25 on the temp. scale. 

 

[bluearmy]

dont see it ida but we can leave it - the ecm op has a spread support (and nor far from the the control run for that matter) but the mean plus the means for gem and gefs continue to run at least one more trough in from the nw into europe to our se post day 10. 

[MKN]

Personally from the model outputs ive seen recently and the length of time left remaining of winter id have it 50/50 now whether the majority of low lying England see lying snow. Think we may have been spoilt these last few years

[winterof79]

Probably the coldest set of ECM long range ensembles of the "winter" so far with 

the mean close to freezing throughout.

 

Also the first appearance of -25 on the temp. scale. 

 

15DAAGSE_06260_NWT.png

Quite Cloud, i posted the self same above.

[karlos1983]

 

 

Finally from me tonight a note of optimism for coldies. Although the evidence for cold is not great at the moment going by tonight's output the building blocks are there to the NE and for those who can think back to my Winter Forecast I suggested then that February offered the best hope for cold and snow this Winter in the UK and that still stands as of now.  

 

Gibby mini ramp alert, BANK

[Gibby]

Personally from the model outputs ive seen recently and the length of time left remaining of winter id have it 50/50 now whether the majority of low lying England see lying snow. Think we may have been spoilt these last few years

The way things are here in Somerset and given the output for the next two weeks no February snow will settle anyway as half the county is under water.

[tight isobar]

lets just remember one thing here, we can get to cold with or without a SSW. If we relied fully on Strat warming to bring cold solely, then because of the time it can take to have an affect at the surface, winter could well be over, but it isn't.

 

I still can't believe some don't think the cold has a chance of coming in the next 10 days, let alone February, look at the charts, it's entirely feasible.frosty has posted just a few of the possible outcomes, they are being modeled, so it *could* happen. I'm not saying mild isn't an option, that would be naive. All to play for.

 

who knows the ever reliable  18z could throw out a BOOM run.

TBH it could (18z) current recent synoptics , reiterate s itself that current blending is by far of no definition. And an outcome for the calendar winter prognosis (last third),could become synopticly, more defined very shortly. And there is a much favoured evolution at present for a colder fruition established, than anytime through this current winter.in normal meteorological one run is one run, but currently its an open option. But things will become firmer. As the hemispherical winter is coming to climax,.heads up .

[Gibby]

Probably the coldest set of ECM long range ensembles of the "winter" so far with 

the mean close to freezing throughout.

 

Also the first appearance of -25 on the temp. scale. 

 

15DAAGSE_06260_NWT.png

The problem is with these they are for De Bilt which is on the cold side of the trough down the North Sea. We in the Uk would not share any of this cold going by the current 10 Day Mean synopses likelihood.

 

http://www.wetterzentrale.de/pics/Reem2401.gif

[damianslaw]

One very strong building foundation for a possible cold spell in Britain is a freezing cold pool to our east - and look what is happening now just that.. The models are predicting a very robust block to form with heights above 1050mb which at this time of year will take some shifting. Remember cold air is much denser than warm air and consequently much harder to shift.

 

The sticking point to getting a colder spell is the position and strength of the PV, the models are suggesting this will remain preety much in situ for the foreseeable future i.e. to our NW and we will be trapped under its spell with energy spilling off it maintaining a flow from between south west and north west - but because of the block to the east the troughs are going to become logjammed across us, trying desperately to go under the block but because of no amplified flow behind we will quickly see another trough feature take each ones place.

 

As I have said for more than a week now, the key to a colder period is an amplified flow developing over Eastern USA Seaboard which will allow for heights to build northwards in the mid atlantic which would at long last give us a clean break from the atlantic allowing the strong heights to our east to mark there influence.

 

The balance of power from the atlantic to a continental pull traditionally shifts to a more even keel as we move into the latter part of February - and if we see the PV weakening substantially there is every reason to expect a much colder and probably drier pattern as we move through the last month of the winter.

 

A word on the models - this is a tricky synoptical set up with small margins for error, best sticking to the 96hr timeframe in such set ups..

 

Oh and those thinking we won't see any snow this winter, I remember thinking the same in both 1993 and 1998 when on the very last day of February we managed our first decent snowfall..

Edited January 21, 2014 by damianslaw

[tight isobar]

One very strong building foundation for a possible cold spell in Britain is a freezing cold pool to our east - and look what is happening now just that.. The models are predicting a very robust block to form with heights above 1050mb which at this time of year will take some shifting. Remember cold air is much denser than warm air and consequently much harder to shift. The sticking point to getting a colder spell is the position and strength of the PV, the models are suggesting this will remain preety much in situ for the foreseeable future i.e. to our NW and we will be trapped under its spell with energy spilling off it maintaining a flow from between south west and north west - but because of the block to the east the troughs are going to become logjammed across us, trying desperately to go under the block but because of no amplified flow behind we will quickly see another trough feature take each ones place. As I have said for more than a week now, the key to a colder period is an amplified flow developing over Eastern USA Seaboard which will allow for heights to build northwards in the mid atlantic which would at long last give us a clean break from the atlantic allowing the strong heights to our east to mark there influence. The balance of power from the atlantic to a continental pull traditionally shifts to a more even keel as we move into the latter part of February - and if we see the PV weakening substantially there is every reason to expect a much colder and probably drier pattern as we move through the last month of the winter. A word on the models - this is a tricky synoptical set up with small margins for error, best sticking to the 96hr timeframe in such set ups..

+96 at best,,,;-)

[fergieweather]

 

The way things are here in Somerset and given the output for the next two weeks no February snow will settle anyway as half the county is under water.

Err, quite, Gibby. Plus depth temperatures still not very low (versus very different scenario last year), so it would have to be something non-marginal other than at sufficient elevation. Anyway - I agreed with your earlier comments. It's been an utterly fascinating winter thus-far, albeit for all the wrong reasons for those affected by flooding. It's a personal view, but the polarised variance from last year has actually made it all the more compelling. I've no reason to think February will prove any less interesting and challenging.

[Cloud 10]

The problem is with these they are for De Bilt which is on the cold side of the trough down the North Sea. We in the Uk would not share any of this cold going by the current 10 Day Mean synopses likelihood.

 

http://www.wetterzentrale.de/pics/Reem2401.gif

 

There doesn't seem to be any major cold blast of air modelled for the UK,but rather a steady descent into colder weather,as indicated when comparing the ECM ensemble mean charts for now and day 10.

 

now..  day 10..

[Jason M]

 Err, quite, Gibby. Plus depth temperatures still not very low (versus very different scenario last year), so it would have to be something non-marginal other than at sufficient elevation. Anyway - I agreed with your earlier comments. It's been an utterly fascinating winter thus-far, albeit for all the wrong reasons for those affected by flooding. It's a personal view, but the polarised variance from last year has actually made it all the more compelling. I've no reason to think February will prove any less interesting and challenging.

 

 

I think the point about soil temps is important. We had a frost here this morning and watching a couple of people trying to navigate the swamp like fields was amusing. There is so much warmth in the environment at the moment given the time of year that the frost had zero impact on the soil. If its laying snow people want, then we need a few hard frosts otherwise as you allude to above it isn't going to lay.