Model Output Discussion

[Mark Bayley]

Another very good GFS this morning, the Parallel is outstanding and keeps the cold throughout the run. I think many would see snow at some point. There will be many changes between now and Thursday so no one should be disappointed about snow distribution as that is subject to change. I can't see this event being an odd wintry shower event with being mostly dry, nor do i see us digging our selves out of the stuff. Some people will do very well, others won't. But wait till nearer the time before we can work this out!

[Nick L]

The whining is irritating me that much im going to refrain from posting until the 12Zs!

Some people seriously need to get a grip and compare these charts to previous Decembers!!

Lastly let me ask the whiners a question. If this was 1947 or 1963 do you really think the models would predict endless E,lys/N,lys?

I think I might join you there TEITS. Starting to get to me. God help us when we go back to classic mild muck (which will happen this winter, it wouldn't be a normal British winter without it). If people are moaning with charts like this just 96 hours away then they have absolutely no sense of perspective:

http://charts.netweather.tv/gfsimages/gfs.20091212/06/96/h500slp.png

As you say, some people need to get a grip.

[Yeti]

The whining is irritating me that much im going to refrain from posting until the 12Zs!

Some people seriously need to get a grip and compare these charts to previous Decembers!!

Lastly let me ask the whiners a question. If this was 1947 or 1963 do you really think the models would predict endless E,lys/N,lys?

Tbh Dave I think it's the constant mentioning of 1947/63 that's driving some people mad on here; there's being realistic, optimistic and then there's just plain ramping and it's been going on too much here imo! I'm not whining - I'm really happy that we have synoptics setting up like they are doing - but despite their similarity to these epic years, their effects will be very different, particularly in terms of depth of cold and snow.

[keithlucky]

Wintery bits? If that chart comes off, the East coast will get an absolute pasting (depending on the strength of the flow, they will penetrate inland).

Anywhere close to the east on that run during thursday will see nothing falling but snow, even right on the coast.

I got to disagree the track of the low pressure system is smack bang over the uk according to the met office pressure charts so anywhere across the uk will get heavy snow especially the north east.

[Spurry]

The parallel certainly offers more hope, is it likely to be more or less accurate than the op run?

[Matt12345]

I think I might join you there TEITS. Starting to get to me. God help us when we go back to classic mild muck (which will happen this winter, it wouldn't be a normal British winter without it). If people are moaning with charts like this just 96 hours away then they have absolutely no sense of perspective:

http://charts.netweather.tv/gfsimages/gfs.20091212/06/96/h500slp.png

As you say, some people need to get a grip.

Fair enough. Problem is when we hit 96 hours away from now that chart wont verify, and another chart like that will show for 96 hours away from then and so on.

[Geordiesnow]

To my un-trained eye, and just reading the posts here, all the potential cold seems to be disappering in the reliable timeframe and continually being pushed back into FI. Seems that we are chasing something we may never catch.

That, i don't agree with, the cold is still being predicted to hit mid-week onwards, i don't think much has changed there.

The snow potential has downgraded compare to recent runs but still time for some minor upgrades though and as i said, GFS is probably under-doing any PPN.

Anyways, i think it's time for me(and perhaps others) to stop reflecting what might of happen if previous runs have occured and concentrate what we do have.

[kold weather]

The easterly is much reduced on this run however thats probably not actually a bad thing for the longevity of the cold spell as that means the upper low over Scandinavia that brings down the low from Greenland has that bit more power...

I'm liking the trend so far, the GFS is probably being once again somewhat progressive once it finally breaks down the northern block but note we are now gettng very close to it showing cold at xmas, which is an improvement on yesterdays run.

Shortwave moves through quicker on this run and the warm sector is even bigger again, easterly spell now moves forward to Thursday instead but only really 12hrs of meanigful time, still enough for one or two places to get a pretty big amount mind you...

[John Snow]

I think I might join you there TEITS. Starting to get to me. God help us when we go back to classic mild muck (which will happen this winter, it wouldn't be a normal British winter without it). If people are moaning with charts like this just 96 hours away then they have absolutely no sense of perspective:

http://charts.netwea.../96/h500slp.png

As you say, some people need to get a grip.

I don't know if I am considered a moaner because I used the word "downgrade" but I was referring entirely to the shortwave which is the key to the severe blizzards that would come with it, the path of the shortwave does seem to be a "downgrade" compared with last night, there will be weeks of cold, there will be reloads but my "downgrade" term was about the shortwave which looks like might miss us now

[Cumulonimbus Tower]

Another very good GFS this morning, the Parallel is outstanding and keeps the cold throughout the run. I think many would see snow at some point. There will be many changes between now and Thursday so no one should be disappointed about snow distribution as that is subject to change. I can't see this event being an odd wintry shower event with being mostly dry, nor do i see us digging our selves out of the stuff. Some people will do very well, others won't. But wait till nearer the time before we can work this out!

I agree about the parallel. Looks remarkably like the ECM at 240h too. Could we really be seeing the firming up of a sustained cold pattern?

[Mark Bayley]

The parallel certainly offers more hope, is it likely to be more or less accurate than the op run?

Its taking over the current OP on the 15th so it is meant to be more accurate, the parallel has been quite consistent over the past few days as well

I agree about the parallel. Looks remarkably like the ECM at 240h too. Could we really be seeing the firming up of a sustained cold pattern?

IMO i always thought the runs were being over progressive in removing the cold, how long the cold lasts is up to debate, but IMO i think will last into the EXMAs period We shall have to see, but as i have kept saying we need to be concentrating on the cold arriving before it leaving

Can i also add that the main cold was never expected to arrive around Thursday, it still looks like it will arrive around this time. Apart from a few hours here and there i can not see this cold spell being pushed back!

Edited December 12, 2009 by mark bayley

[Osbourne One-Nil]

You know what, some of you should step away from the computer, go outside, have a walk on this lovely, seasonal, calm winter's day and just wait and see what happens. For someone who can't read a model to save their lives, it is so utterly frustrating to have to trawl through countless posts containing nothing but subjective comments based on one run.

I sometimes do seriously wonder if some people think the models actually affect the weather we get...I really do.

[TEITS]

Tbh Dave I think it's the constant mentioning of 1947/63 that's driving some people mad on here; there's being realistic, optimistic and then there's just plain ramping and it's been going on too much here imo! I'm not whining - I'm really happy that we have synoptics setting up like they are doing - but despite their similarity to these epic years, their effects will be very different, particularly in terms of depth of cold and snow.

The point im making about 1947, 1963 is to illustrate how the models will never accurately predict this cold spell outside of +72.

What frustrates me is the short memories some people have. Why is it that if the models show a slight downgrade there is this assumption it will occur. However why is it some have forgotton about the poor ECM run the other day and how this has significantly upgraded since then!

Personally I find the wild mood swings on this thread very frustrating. Ironically its often those who moan about downgrades who are the first to ramp at upgrades!!

[kold weather]

I don't know if I am considered a moaner because I used the word "downgrade" but I was referring entirely to the shortwave which is the key to the severe blizzards that would come with it, the path of the shortwave does seem to be a "downgrade" compared with last night, there will be weeks of cold, there will be reloads but my "downgrade" term was about the shortwave which looks like might miss us now

It was never goin to give us snow down in the south, I said last night the only places that really stand much of a chance is the NE and Scotland, but even the NE looks very marginakl now indeed according to this run.

The cold air does tuck in quickloy behind it though so could see some back edge snow.

Also, we may well be seeing some signs of this cold spell becoming very sustained indeed...worth watching IMO...lets just say this already looks like being one of the more potent 14 day periods we've had in the 2000s, be interesting to see where about it ranks afterwards...if there is an afterwards!

[Methuselah]

Can I repeat: there's no problem with people's posts/views on the models reflecting their-own areas!

It's not 'bias' - it's reality...For instance, why would I base my prognostications on what the GFS shows for The Old Kent Road??

Cut each-other some slack!

[kold weather]

Can't stand this today , take a breather everyone. Still no mild SW or Atlantic air coming in. All looking good for a very cold week . I'm out of here till later , some people need to relax a bit.

To be honest thats the key, the models aren't that snowy today away from the usual places (though they will start to show some disturbances I bet) ad the easterly has shortened quite a lot but the overall set-up lasts for longer which is a very good thing of course.

The Paralell is stunning, there are some similarities between December 1981 on a few of those charts though its doubtful whether it'd be quite that cold.

Remember the longer we have this cold set-up lasting the more oppertunities there will be for snow!

[grab my graupel]

This is getting rather tiresome, folks.

Please bear in mind that this is the Model thread and there are other threads available

for Ramping/Whining and general cold weather chat.

Let's not spoil it for the other members

Brian

[Yeti]

The point im making about 1947, 1963 is to illustrate how the models will never accurately predict this cold spell outside of +72.

What frustrates me is the short memories some people have. Why is it that if the models show a slight downgrade there is this assumption it will occur. However why is it some have forgotton about the poor ECM run the other day and how this has significantly upgraded since then!

Personally I find the wild mood swings on this thread very frustrating. Ironically its often those who moan about downgrades who are the first to ramp at upgrades!!

Now that I couldn't agree more with - my point is just that I think certain people should be more realistic about the intensity of the cold to come - as indeed you are IMO - rather than suggesting nationwide gridlock and disruption as was rife last night!

Of course things can still change, but there is not really any doubt now that we are NOT heading for a real deep freeze like 87, 91 etc. as some have been hinting at. Granted, it might have looked like that a few days ago, but things have now changed. Whining though is ridiculous because I personally can't wait for the cold to arrive and I'll be happy with anything seasonal in the offering (it beats the usual!). And that's coming from somebody who knows that the chance of decent snow here is next to 0, despite absolutely frigid temperatures.

[johnholmes]

You know what, some of you should step away from the computer, go outside, have a walk on this lovely, seasonal, calm winter's day and just wait and see what happens. For someone who can't read a model to save their lives, it is so utterly frustrating to have to trawl through countless posts containing nothing but subjective comments based on one run.

I sometimes do seriously wonder if some people think the models actually affect the weather we get...I really do.

thanks OON

IF only some would read this and do as you suggest-its a shame none of us have the time to copy and save some of the dafter posts in here and then re produce them at a later date for the forum to see who the main twerps are.

okay mods off topic I know

back to the models and I have to ask the question-of course as ever we will not know if it actually does happen until two weeks from here. However, all models show cold possibly very cold (by Met O definition) over much of this week. The 2 models which go beyond T+144 also suggest it could last a good deal longer. How many of you, hand on heart, can remember 10 days of cold/very cold weather occurring over the past 10 years-indeed over the past 20 years? I am talking about December not January or February data.

As OON says take a break-calm down-enjoy what you get if its cold you want-some will get snow and for some it will lie-its not quite the shortest day so its likely to stay a few days for the lucky ones.

Its coming up to Christmas so how about a little Christmas good will to all from some of you.

departs to play in his own blog area where it is much much less frenetic and so far devoid of ya boo comments.

[kippure]

I havent looked at the last 4 runs, Untill this mornings 06z run. All still looks good. But arent we coming up to a peak energy period soon? Could some one verify that for me? This will make very very interesting model watching.

[mcweather]

The point im making about 1947, 1963 is to illustrate how the models will never accurately predict this cold spell outside of +72.

What frustrates me is the short memories some people have. Why is it that if the models show a slight downgrade there is this assumption it will occur. However why is it some have forgotton about the poor ECM run the other day and how this has significantly upgraded since then!

Personally I find the wild mood swings on this thread very frustrating. Ironically its often those who moan about downgrades who are the first to ramp at upgrades!!

I,m with you on this one Teits.

There are some people on other sites talking about the christmas warm up shown in deep FI on this mornings 06gfs as if it is already nailed on. If the gfs ensembles had existed at christmas 1962 there would no doubt have been runs suggesting that the cold would break down by new year. ECM ensembles looking good.

[weather eater]

Just to come back to this, because it is an issue on the model thread. There are no upgrades and downgrades by the models, they evolve. Before a model is run its data is updated to reflect the latest conditions and it will be progressively different from the last run, the further it gets from zero. Anybody looking at charts for 72, 96, 120, 144hrs ahead and thinking that the run will happen exactly the same as the last will be disappointed. In regards the situation we are in now, who knows where this is going, the models don’t, some have it breaking down before Christmas, on other runs the cold goes right through to the end, it is possible that this is just the start of a memorable winter, or it might be that this is all we see. But please manage your expectations don’t take mega blizzards or even the position of a shortwave feature progged at 96hrs, 120hrs as gospel, better in fact to dismiss it from your mind than assume that this is now a fixed point.

[kold weather]

ECM ensembles still showing an awful lot of scatter, no doubt as they are trying to come to grips with the shortwave and its movement, that would suggest to me that could yet be more changes in that regards, may not be totally nailed on yet...the op run was on the colder side though it should be noted...

Anyway I'm liking the trend, and as John correctly said there's been few 10 days spells thayt have been cold in this decade, Jan 2009 was one, March 2006 had another and Feb 2005 was another, beyond that and my knowleadge becomes more patchy...

[johnholmes]

thank you WE that has to be one of the most sensible posts in this thread this morning

[bluearmy]

the advertised pattern of icelandic high/scandi trough looks a lot like what was being shown by joe B on his late dec/early jan pressure pattern chart around a month ago. if he got this right, then it could well be a long hard slog through the next 6 to 8 weeks. (both outside in the real world and also in our virtual world unless a few peeps chill out a bit)