Model Output Discussion - The Run In To Christmas

[Backtrack]

A rare post from but that GFS 12z para run looks a bit of a nonsense to me. In a space of 60 hours, it goes from nothing to nothing with a mother of all storms interval.

 

Rapid cyclogenesis. 

[Polar Maritime]

Again the GFSP shows a very Stormy period around the 27th, Quite a concern i would think..

 

[Matty M]

Some real uncertainty showing in the GFS ensembles as early as Christmas Eve

 

There are a good few members going for a troublesome little low tracking through Scotland with high winds and then potential for Sig snow in some places. (@ just 90hrs we have significant model divergence)

 

One to watch... a very difficult period to forecast once we lose this drab weather in the next few days,,

 

Edited December 20, 2014 by Matty M

[linarite]

The GFS PARA models a quite extraordinarily severe event for 27th/28th, combined with a spring tide. We must hope for the sake of the north-east and  east coast that this downgrades.

[Muffelchen]

The models' ambivalence as to what happens on or after Christmas Day continues. The spectacular looking LP for 27th would indeed be interesting, but I guess the chances of anything like it happening at this distance are pretty remote, although having said that, it is a possibility.

 

What I find odd still is that there have been no real signs within the models of a pressure build from the NW after Christmas. Pressure rises to the S or SW yes, but that is all. Several days of cold air coming S across the Norwegian Sea, LP much weaker over Scandinavia, a situation which has in the past given rise to some noteworthy frontal battle grounds between cold and mild.

 

Here's a nice example from 1982.

 

archivesnh-1982-1-6-0-0.png

 

That one produced significant snow across the S as an advancing frontal zone stalled as it pushed into the cold air to the N.

 

As always, I am aware that no 2 situations are ever the same, and I wouldn't mention it but for the indecisiveness of model output at that time, but it's an intriguing possibility and, dare I say it, no less unlikely than the GFS major storm!

 

It will be interesting to see later model output and whether we have any sort of consensus developing.

I remember this one very well. I was living in Pembroke at the time and the wind was in the East and gusting close to 100mph. It was bitter and the snow was relentless for about 18 hours. However, this was just the start. During the following day (7th Jan) the snow eased off and turned to freezing rain which coated everything in a layer of ice up to 2 inches thick. This was followed by another 12 hours of snow and everywhere lost all their electricity, which was not restored for three weeks. Trees had shed branches, telegraph poles had snapped and hundreds of pylons from Pembroke Power Station collapsed in situ. The drifts were as high as houses and, combined with Pembrokeshire's tall hedges and banks, there were blocked roads with no-one to clear them. The army brought  food on half tracks and everything just froze solid. I am pretty sure that the UK's lowest ever temperatures were recorded during the week following this event.

 

I knew at the time this was special: it was even more extreme than the blizzard of 1978, and I knew at that time I would probably never see the like again (certainly in the UK) and I have not. I have never seen a true blizzard since and have only seen two in my life. They are scary beasts but is was the blizzards of 79 and 82 that kindled my love of the weather: a love I have never lost.

[Barry12]

UKMO, GFS, GFS P all agree at 120 hours, the ECM will backtrack on this run...

 

:smiliz19: :w00t: :smiliz64:

Edited December 20, 2014 by Barry95

[bobbydog]

......and the above 2 posts #1281 #1282 is why I have no clue as to what's going on.

 

(Not a knock on you two above but more an obs on how difficult it is to read the situation  )

part of the learning curve of model watching and how to read the models, is also how to read the posts in this thread. you have to learn which posters know what they are talking about,

which posters think they know what they are talking about

and which posters are talking absolute b*!!@×s

[Fred Sykes]

Looking at the models, there's got to be a good chance of a white Xmas somewhere in the UK! I've never put a bet on before, but quite fancy a £20 bet this year. Where would you bet on? Aberdeen is a good shout, but rubbish odds!

[Matty M]

The GFS control is a worrying run as it races a rapidly developing winter storm across the UK on Boxing Day...

 

 

Edited December 20, 2014 by Matty M

[10 Days Away]

part of the learning curve of model watching and how to read the models, is also how to read the posts in this thread. you have to learn which posters know what they are talking about,

which posters think they know what they are talking about

and which posters are talking absolute b*!!@×s

 

I know what posters I'm looking for but I have to glance 30 odd posts to try and find one of the said posters that seem to know their stuff, I realise I have added to the ratio .. and will now shut up.

Edited December 20, 2014 by TN26

[Frosty.]

After a few wobbles we are back on track for a wintry outlook, hopefully a much improved ecm 12z will occur this evening to keep the happier mood on here. :-)

[Blizzardof82]

The models' ambivalence as to what happens on or after Christmas Day continues. The spectacular looking LP for 27th would indeed be interesting, but I guess the chances of anything like it happening at this distance are pretty remote, although having said that, it is a possibility.

 

What I find odd still is that there have been no real signs within the models of a pressure build from the NW after Christmas. Pressure rises to the S or SW yes, but that is all. Several days of cold air coming S across the Norwegian Sea, LP much weaker over Scandinavia, a situation which has in the past given rise to some noteworthy frontal battle grounds between cold and mild.

 

Here's a nice example from 1982.

 

archivesnh-1982-1-6-0-0.png

 

That one produced significant snow across the S as an advancing frontal zone stalled as it pushed into the cold air to the N.

 

As always, I am aware that no 2 situations are ever the same, and I wouldn't mention it but for the indecisiveness of model output at that time, but it's an intriguing possibility and, dare I say it, no less unlikely than the GFS major storm!

 

It will be interesting to see later model output and whether we have any sort of consensus developing.

My username is from this event, best snow in Bristol in my lifetime.

 

Looking at latest output the GFSp has been very consistent in modelling this storm around the 27th/28th, I guess we will soon see how well the GFS younger newer Brother performs.

[MR EXTREMES]

But the ecm refuses to give up and it's likely to be correct as the noaa posts earlier back the ecm

[Backtrack]

part of the learning curve of model watching and how to read the models, is also how to read the posts in this thread. you have to learn which posters know what they are talking about,

which posters think they know what they are talking about

and which posters are talking absolute b*!!@×s

 

Hardly fair post BD, I contribute what I can, I don't know a great deal, but when I see something that I think may add some sort of value or discussion point to the thread, I'll post it. If every user reading the topic were looking for posts from the likes of Nick Sussex, Ian F & Lorenzo etc, then there would be about 50 pages just overlooked, just because some members are new to this, or like myself have a fairly limited knowledge base compared to some others, does this mean I'm talking as you say 'absolute b*!!@xs'? I don't see you contributing to this thread. 

 

It's posts like yours that prevent people from posting, or scare people away from this thread. 

 

So tell me, because I prematurely called out the 12z as a mild run when it showed MILDER synoptics for Christmas & Boxing Day, when compared to the 06z, how does that make my post rubbish?

 

I'm done posting in this thread now. Have fun.

Edited December 20, 2014 by Backtrack

[Barry12]

But the ecm refuses to give up and it's likely to be correct as the noaa posts earlier back the ecm

 

When the UKMO, GFS and GFS P all disagree with the ECM at 120 hours, I don't see how it's 'likely' to be correct...

[SHM040519]

When the UKMO, GFS and GFS P all disagree with the ECM at 120 hours, I don't see how it's 'likely' to be correct...

 

 

Its happened before! 

[Snowman.]

The 0z run wasn't even THAT bad.

 

The GFS op runs have been far worse imho.

[IDO]

The GEFS at D7-8 are saying yes to amplification in the Atlantic. Strong support now for this. The D7 & D8 mean: 

 

 

 

The individual members mainly show that the LP system will eject from the trough N/NE into the jet and hit somewhere over the UK:

 

 

 

This is in tandem with a flow of cold uppers being pulled south by the GH. the Hi-res are probably the best to get a grip on how the low will develop. The Control at D6-D7 for instance: 

 

 

 

Obviously the GFS suite is keeping to its guns re the early Northerly but it is very fluid on how that LP system blows and fills. There is cold air in the mix and that may bring its own problems but that is for a nearer time period. How the LP fills and its track is only part of the equation for the following period as it is clear the upstream pattern is variable and by D11 there are MLB over the UK, Scandi and GH, but the main cluster is an Icelandic ridge. All likely to change again on the next run at that time scale though.

 

See if the ECM starts to back its mean...

Edited December 20, 2014 by i'm dreaming of...

[Tim Bland]

I have a feeling the ECM will back down, if not on the 12z then the 00z. I usually have faith in it but it has been an outlier against its ensembles for the past 4 runs now.

[Banbury]

The 0z run wasn't even THAT bad.

 

The GFS op runs have been far worse imho.

http://www.meteociel.fr/modeles/ecmwf/runs/2014122000/ECH1-216.GIF?20-12

 

Correct , it wasn't exactly a disaster was it

[Jason H]

Hardly fair post BD, I contribute what I can, I don't know a great deal, but when I see something that I think may add some sort of value or discussion point to the thread, I'll post it. If every user reading the topic were looking for posts from the likes of Nick Sussex, Ian F & Lorenzo etc, then there would be about 50 pages just overlooked, just because some members are new to this, or like myself have a fairly limited knowledge base compared to some others, does this mean I'm talking as you say 'absolute b*!!@xs'. I don't see you contributing to this thread. 

 

It's posts like yours that prevent people from posting, or scare people away from this thread. 

 

So tell me, because I prematurely called out the 12z as a mild run when it showed MILDER synoptics for Christmas & Boxing Day, when compared to the 06z, how does that make my post rubbish?

 

I'm done posting in this thread now. Have fun.

 

It's not scaring people away at all. I'm afraid post like your original one, although well meaning, confuses people and that puts people off posting. Just let the runs unfold and then voice an opinion. I don't think he implicitly said your post was rubbish. It was a light hearted post in general. No malice intended.

 

Shame you won't be posting any longer. If you cannot take criticism for a post on a weather forum, perhaps it would be better for you not to post?

 

Awaiting the ECM to see if the puzzle can be solved. I doubt it will though

[mushymanrob]

When the UKMO, GFS and GFS P all disagree with the ECM at 120 hours, I don't see how it's 'likely' to be correct...

Except when its shows cold and the others mild.

[Barry12]

Except when its shows cold and the others mild.

 

Nope not really, I still wouldn't believe it.

[10 Days Away]

Hardly fair post BD, I contribute what I can, I don't know a great deal, but when I see something that I think may add some sort of value or discussion point to the thread, I'll post it. If every user reading the topic were looking for posts from the likes of Nick Sussex, Ian F & Lorenzo etc, then there would be about 50 pages just overlooked, just because some members are new to this, or like myself have a fairly limited knowledge base compared to some others, does this mean I'm talking as you say 'absolute b*!!@xs'? I don't see you contributing to this thread. 

 

It's posts like yours that prevent people from posting, or scare people away from this thread. 

 

So tell me, because I prematurely called out the 12z as a mild run when it showed MILDER synoptics for Christmas & Boxing Day, when compared to the 06z, how does that make my post rubbish?

 

I'm done posting in this thread now. Have fun.

 

This is not directed at you Backtrack,

 

Clearly the forum needs active members to ensure it earns well. (The more unique visitors the more money you can get from advertisers) but on the flip side writing the first thing that enters someones head isn't always worth writing down and just confuses the issue and clogs up the forum)

 

I have been astounded before when someone with 1000+ has posted a a question about something that even I knew the answer to. This proves the point I think

[winterof79]

After a few wobbles we are back on track for a wintry outlook, hopefully a much improved ecm 12z will occur this evening to keep the happier mood on here. :-)

Hi Frosty

You know ECM will go mild just to keep the wrist slashers happy. Seriously though I feel we are in for a proper winter storm after 25th which will be the precursor to the pattern change.Enjoy.

Edited December 20, 2014 by winterof79