Model Output Discussion

[MR EXTREMES]

ukmo similar with a deep depression from the sw good for northern england and scotland with -8 uppers holding on but same trend certainly most of the uk can look forward to less cold and very wet conditions.

Edited February 18, 2010 by badboy657

[SP1986]

you and I just have to disagree Stephen. Until you produce hard evidence, and over several weeks, to support your theory-it is just that-theory.

Evidence and I'll believe you then maybe we can look at what might be a way of applying corrections on NW in those particular circumstances. Until then St its just you posting oft with no proof.

and your comment to the other poster not believing you that he should go and prove his theory is simply not on-you are the one posting about inaccuracies so its up to you to prove your view not the other way round-as a scientist you should know that.

sorry if I sound harsh St but you really do have to prove your point-you MAY be right but you have to show proof over a period of time-PLEASE?

I'm not sure where you get this idea that I am or should be a scientist, I don't have a scientific mind.

To get the proof I'm going to have to save charts - I will do, I will get a collection of forecast charts and measure them up against actual returned temperatures, it will take a little time because one chart doesn't prove anything, I'm happy to attempt to prove what I'm seeing.

I don't anyone to get the idea that I'm dismissing every temperature output on the GFS, because I'm not, I think most of the time it handles it well and I can't find anything to grumble about, but there have been times more frequently since the new update came out that the GFS has gone for -10 or -12C and in most times they have not materialised.

I understand that people need evidence and I will do my best to try that although I'm running out of time to prove it because of the onset of Spring.

This is by no mean proof but the 12z has already removed some of the extremely low temperature that were shown in yesterdays output so I will be making a reference of that, although I didn't save the 18z, 0z, and 6z charts.

[kold weather]

Its pretty much got rid of the risk for a big snow event HG, the models upto the 12z suite were hinting at a major snow event...now they suggest a rainfest for all but the far north.

As you say we get a rather poor 2nd prize, almost a sort of sympathy system that comes in and does give a probably a half decent event BUT the air would be amazingly marginal in that evolution, far more so then even today...

Lets say I'm not impressed in the slightest by the models so far, and they probably have spotted a trend that they will stick to as well now...as I said its a good run for Scotland but elsewhere its not the greatest we've seen recently...BUT it does give a little something to the south...in the end...

[MR EXTREMES]

lol today was going to be cack according to some posters on monday and outside the story is a winter wonderland.

Still plenty of snow potential in the charts for next week, people getting too hung up on specifics as usual and not looking at the overall potential.

http://www.wetterzen...s/Rtavn1321.png

well all i can say sometimes things dont go the way some might wish for but as gp has said its not total downgrade for the north.

i dont think its a case of getting hung up more really to the agreement of the models not only for today but the last 3 days.

it had to breakdown in the end.

[Cheese Rice]

GFS certainly changed some what, there is still plenty of potential. I am surprised by Sunday/Monday with the low making its way to Scotland, I can't really see it making it that far north, at least the low gets eaten up by the cold air. Its only one run but will bring huge amounts of snowfall to Scotland, at times heavy snow for Northern England and Ireland with the risk diminishing for the midlands south. But as I said earlier it is one run and will keep chaining.

[kold weather]

lol today was going to be cack according to some posters on monday and outside the story is a winter wonderland.

Still plenty of snow potential in the charts for next week, people getting too hung up on specifics as usual and not looking at the overall potential.

http://www.wetterzen...s/Rtavn1321.png

Not really, thats rain for most and maybe sleet, only snow for the far northern and western edge of the rainband, thats because that low that comes up washes away all the colder air at the surface and there isn't nearly enough drag back down from the north to replace it, which makes thing amazingly marginal, to the point where you'll be lucky to get more then a very brief bit of snow towards the last hour of the band.

Flooding is a big risk in the south, in fact I'd say its quite likely based on this run...big snowfall for the north and Scotland on this run

Edited February 18, 2010 by kold weather

[Eugene]

How is 2C with precipitation around on monday terrible please if you want terrible go and look at winter 1988/89 charts, GFS 12Z is a stunning run for next week and not terrible at all.

http://www.wetterzentrale.de/pics/Rtavn1681.png

　

[johnholmes]

apologies for calling you a scientist-thanks for saying you will collect the data and what the actual temperature subsequently showed for whichever part of the country you question. Yes its a big job, as you know from my days of T+168 GFS checks over 3 years-don't expect you to do it for 3 years but 2-3 months would lend weight to whatever the test show.

tks again

[Higher Ground]

Its pretty much got rid of the risk for a big snow event HG, the models upto the 12z suite were hinting at a major snow event...now they suggest a rainfest for all but the far north.

As you say we get a rather poor 2nd prize, almost a sort of sympathy system that comes in and does give a probably a half decent event BUT the air would be amazingly marginal in that evolution, far more so then even today...

Lets say I'm not impressed in the slightest by the models so far, and they probably have spotted a trend that they will stick to as well now...as I said its a good run for Scotland but elsewhere its not the greatest we've seen recently...BUT it does give a little something to the south...in the end...

Yes, fair enough. I just checked the UKMO and it's quite a sharp left turn from the low between +72 and +96 hrs. Sure, if that happens, it's likely a major step towards a more "normal" atlantic pattern. *If* that happens.......hmmmmm...... but then it is well into the traditionally reliable timeframe. Wouldn't want to call it just yet considering all the talk of fat ladies entering the building the past week, only for it to turn out they couldn't make it through the marginal snow.....

[Nick L]

I'm not sure where you get this idea that I am or should be a scientist, I don't have a scientific mind.

To get the proof I'm going to have to save charts - I will do, I will get a collection of forecast charts and measure them up against actual returned temperatures, it will take a little time because one chart doesn't prove anything, I'm happy to attempt to prove what I'm seeing.

I don't anyone to get the idea that I'm dismissing every temperature output on the GFS, because I'm not, I think most of the time it handles it well and I can't find anything to grumble about, but there have been times more frequently since the new update came out that the GFS has gone for -10 or -12C and in most times they have not materialised.

I understand that people need evidence and I will do my best to try that although I'm running out of time to prove it because of the onset of Spring.

This is by no mean proof but the 12z has already removed some of the extremely low temperature that were shown in yesterdays output so I will be making a reference of that, although I didn't save the 18z, 0z, and 6z charts.

Hi Stephen, as I made the counter claim to your theory I am willing to help out in collecting charts and comparing them to real temps.

[Matty M]

Do i spy a polar low crossing Ireland tomorrow night!??

[nick sussex]

The UKMO at 144hrs looks like finally beginning to transfer the western based negative NAO further east, its very close to a very good chart with less phasing between the Scandi trough and energy in the southern arm of the jet.

Hopefully we'll see the ECM follow this and bring a change towards the end of the month with pressure rising to the north and ne and moving away from this current slushy wintry mix pattern to one last proper cold spell with less marginality into the start of March before we have to wave goodbye to winter.

[MR EXTREMES]

How is 2C with precipitation around on monday terrible please if you want terrible go and look at winter 1988/89 charts, GFS 12Z is a stunning run for next week and not terrible at all.

http://www.wetterzen...s/Rtavn1681.png

　

lol i cant help but say are you holding on to the cold yourself because i and others dis see this coming,

it was bound to happen sooner or later.

and as others have mentioned the north will do well out of this cumbria mountains of wales and ofcoarse scotland ni,

rest of the country does look wet and rather windy but not mild neither cold enough but slightly below,

the met office also from there outlook see similar aswell.

[Higher Ground]

lol i cant help but say are you holding on to the cold yourself because i and others dis see this coming,

it was bound to happen sooner or later.

and as others have mentioned the north will do well out of this cumbria mountains of wales and ofcoarse scotland ni,

rest of the country does look wet and rather windy but not mild neither cold enough but slightly below,

the met office also from there outlook see similar aswell.

To be fair you and others have seen this coming (just outside the reliable timeframe, or even occasionally within!) for months LOL

GFS +180 and jet continues well south after all?

Edited February 18, 2010 by Higher Ground

[kold weather]

How is 2C with precipitation around on monday terrible please if you want terrible go and look at winter 1988/89 charts, GFS 12Z is a stunning run for next week and not terrible at all.

http://www.wetterzen...s/Rtavn1681.png

Its terrible considering what we could have, which you should be fully aware...2C and cold rain is not my idea of fun to be honest Eugenbe, because thats what the profiles would suggest, lovely cold rain for 85% of the Uk!

Still on the side of balance, it is a decent enough run for the north of England, with a decent snow event up there as well as S.Scotland as well but to be honest its still poor compared to what could be...its all relative. Is it as bad as 88-89, not a chance in hell is it as bad because at least we do have snow risks...but it'd be a shame to waste such a grand chance to have one of the snowiest spells in recent history...because there was that risk IMO...

Edited February 18, 2010 by kold weather

[cooling climate]

the cold air in scandi trying to push sw on the gfs 54h.

might close to the east of the uk -12 850s but east ends up with -8 which is good its only one run from 1 model.

edit: 66h close but no cigar it slips south down towards germany and you see the milder air pushing in from the sw.

thats what i mean cooling climate its easy to jump to conclusion until you see the way its heading the area of margin now heads for northern england.

I was only referring to the low today that is bringing the rain and snow on previous runs the low was on a

more northeasterly track.

There is so much inter run variability at the moment from all models regarding the lows and movement of the

segments of vortices's that beyond 72 hours is a waste of time at the moment. With the MMW and the

splitting of the vortices's the models are expected to become quite volatile over the next few days.

[Cheese Rice]

lol i cant help but say are you holding on to the cold yourself because i and others dis see this coming,

it was bound to happen sooner or later.

and as others have mentioned the north will do well out of this cumbria mountains of wales and ofcoarse scotland ni,

rest of the country does look wet and rather windy but not mild neither cold enough but slightly below,

the met office also from there outlook see similar aswell.

I think you're holding onto mild the best you can, you're posts have been mild before this cold spell has begun. And so far the "break down" has yet to make it past T160, even though the models have consistently shown a breakdown at T160 this is been showing everyday and is not getting any closer.

Its terrible considering what we could have, which you should be fully aware...2C and cold rain is not my idea of fun to be honest Eugenbe, because thats what the profiles would suggest, lovely cold rain for 85% of the Uk!

If you're talking about the GFS this is only one run showing this, the previous run was relatively snowy and brings the low out of nowhere out to Scotland which seems unlikely.

Edited February 18, 2010 by 10123

[LomondSnowstorm]

I'm the only one who thinks the 12Z is an upgrade! Perhaps a bit further south to keep colder air in place but in many ways this spell was becoming less interesting for those in Scotland due to the majority of the precipitation being further south. Just a different opinion on it but of course others will inevitably disagree. Outwith the lows is not really worth thinking about given the models continue to show this breakdown at the start of FI/end of high resolution but it hasn't really moved too much in the last few weeks to be honest.

LS

[kold weather]

Its not just the GFS, the 12z UKMO does pretty much exactly ther same thing in its 12z run, and the ECM has also been flirting with that idea in recent runs...

My conclusion on this run is another marginal snow event for Midlands, better for the west on Saturday, rain in the south...again...then more rain for Sunday-Monday with maybe brief snows on the northern edge before becoming a high ground event further north on Monday...then another high ground event for the south/Midlands at 132hrs...

So all in all whilst its not a complete disaster, its not great by any means either IMO, a couple of extreme broderline set-ups which could all be total washouts doesn't seem that great IMO.

[Severe Siberian icy blast]

Its terrible considering what we could have, which you should be fully aware...2C and cold rain is not my idea of fun to be honest Eugenbe, because thats what the profiles would suggest, lovely cold rain for 85% of the Uk!

Still on the side of balance, it is a decent enough run for the north of England, with a decent snow event up there as well as S.Scotland as well but to be honest its still poor compared to what could be...its all relative. Is it as bad as 88-89, not a chance in hell is it as bad because at least we do have snow risks...but it'd be a shame to waste such a grand chance to have one of the snowiest spells in recent history...because there was that risk IMO...

But let me remind ppl for the last 4 runs or so its been goin for the lows further south and now after one run your talking like its game over , i would imagine this is an outlier , i cant see these lows making it that far north , it does this alot.

[MR EXTREMES]

I think you're holding onto mild the best you can, you're posts have been mild before this cold spell has begun. And so far the "break down" has yet to make it past T160, even though the models have consistently shown a breakdown at T160 this is been showing everyday and is not getting any closer.

If you're talking about the GFS this is only one run showing this, the previous run was relatively snowy and brings the low out of nowhere out to Scotland which seems unlikely.

thats because this is the model output discussion and i have simply been watching thease models so closely since our last real cold event in january,

and since then everything has been so close but not cigar most caused but sortwave movemnet and west based nao.

some of my reasons for calling breakdown from cold was dues to the nature of the messy outputs once this took hold,i see the reasons why a true deep cold evolution like some had been suggesting was not going to happen purely because of the activity in our atmosphere low pressures swirling around our country with no real deep cold to tap into add the fact milder are is easier to tap into there for the reson for marginal events.

the models are not broken and have been showing clearly this trend so shoot me down as much as you like for what i see but as is being suggested a east based nao into march is always a possibility and i hope it does happen although im skeptical if it will and whether in early spring it will have the effect the coldie camp is hoping for.

as i said snow in april march even june is always possible so im only saying i what ive been seeing on the models,

is that ok or am i not aloud to go against the grain.

[Solar Cycles]

Its not just the GFS, the 12z UKMO does pretty much exactly ther same thing in its 12z run, and the ECM has also been flirting with that idea in recent runs...

My conclusion on this run is another marginal snow event for Midlands, better for the west on Saturday, rain in the south...again...then more rain for Sunday-Monday with maybe brief snows on the northern edge before becoming a high ground event further north on Monday...then another high ground event for the south/Midlands at 132hrs...

So all in all whilst its not a complete disaster, its not great by any means either IMO, a couple of extreme broderline set-ups which could all be total washouts doesn't seem that great IMO.

To me it looks like the GFS is doing what it as done all winter, and that is by putting too much engery in the Northern arm of the jet. Come nearer the time , that front won't make it any further than Northern England, probably not even that far North!

[Cheese Rice]

Its not just the GFS, the 12z UKMO does pretty much exactly ther same thing in its 12z run, and the ECM has also been flirting with that idea in recent runs...

My conclusion on this run is another marginal snow event for Midlands, better for the west on Saturday, rain in the south...again...then more rain for Sunday-Monday with maybe brief snows on the northern edge before becoming a high ground event further north on Monday...then another high ground event for the south/Midlands at 132hrs...

So all in all whilst its not a complete disaster, its not great by any means either IMO, a couple of extreme broderline set-ups which could all be total washouts doesn't seem that great IMO.

I think overall since the cold spell has begun it has been better than expected, at first it was only northern areas expected to see snow, now at times now a risk is for Midlands south-wards. So while not as good as some of the previous runs, the original runs which first showed the idea of low pressure over the UK didn't shown -5 850's over midlands so an upgrade if we can forget about the last few runs.

Edited February 18, 2010 by 10123

[MR EXTREMES]

We still have the ecm to come and theres perhapes a chance of a neg nao so must be a fult with the input into the models.

thats the only other conclution i can come to but they all look pretty similar in one way or another:whistling:.

and to be perfectly honest this cold spell:whistling: was ment to be a raging easterly if i remeber rightly then the shortwave and neg nao put pay to that idear from the models,

so now its moving in the oposite direction to a very much more wet unsettled idear.

Edited February 18, 2010 by grab my graupel

[January Snowstorm]

These are not dry charts at the wkd, conditions are spot on for polar low development

Polar low is of course technically incorrect, more like disturbances developing caused by deeply cold uppers over the North Sea

I see no reason to change my thoughts from last night.

Widespread snow over central/southern Ireland on Friday & Saturday night!