Model Output Discussion 5/12/2012 18Z onwards - the one after THAT ECM

[Frosty.]

There have been sly hints today from certain forecasters about the easterly, they must be onboard with it by now. The model output today (op runs and ens mean) are all on the same page with a potent cold blast from the east by early next week, the crucial trigger low is now fairly well modelled for sunday to bring the first wave of colder air south and that process then speeds up early next week with progressively colder air being drawn southwest across the uk, unless there is a monumental backtrack, we will be having ice days quite soon and some will have major snowfalls.

Edited December 6, 2012 by Frosty039

[Fozfoster]

http://cdn.nwstatic.co.uk/ecmimages/20121206/12/ecm500.216.png definitely not flat.sorry its short but seeing if paste is working again!!

[bluearmy]

the ecm ens mean in its latter stages is definitely drifting the solution further north. however, i have seen the model do this so many times with the mean trending with the op and being wrong by the following run that i think it worth waiting for tomorrow before commenting further.

[cold snap]

There have been sly hints today from certain forecasters about the easterly, they must be onboard with it by now. The model output today (op runs and ens mean) are all on the same page with a potent cold blast from the east by early next week, the crucial trigger low is now fairly well modelled for sunday to bring the first wave of colder air south and that process then speeds up early next week with progressively colder air being drawn southwest across the uk, unless there is a monumental backtrack, we will be having ice days quite soon and some will have major snowfalls.

Lol at sly hints ,love them sly hints and cheeky winks at the end lol ,then you know it's out there it's in there mind

[Duane S.]

<rant>The only downgrade today has been some the complete tosh posted on this forum since the 12zs rolled out. Yes it's a model discussion chart and I can excuse some people new to all of this getting over-excited when a chart isn't as good as the one from 6 hours earlier and taking things at face value but there are some seasoned posters who just seem to ruin it for everyone with their constant inaccurate comments that from what I can see are based only because their area is not looking as good as it was looking on the last model run. Let's be objective because this is far from set in stone but this?</rant>

There's obviously no telling some but if I can get through to those new to all of this, forget all about "It's a dry run, no snow!!", "the 850s are not as low on this run!!", "argghhh the -5 isotherm hasn't moved as far south at +144 as 6 hours ago!!", "Oh no! It's a NE, not an E flow!!" honestly, with the onset of an easterly, it will drive you to the point of insanity on preceeding model runs as they always and without fail switch about all over the place as we hone in. And lastly, don't measure a GFS run up against anything else than the GFS from 24 hours earlier, if not, you may as well measure it up against another model frankly.

Anyway... as far I'm concerened it's a big upgrade on yesterday's 12z's and offered these beforehand I want have snatched it in a blink. Why? Because we are 24 hours closer and it's still game on. NO major spoilers have entered the fray!

The GFS is another great run that continues the ride to a cold Easterly but then goes on to offer up a crazy trough extension at about T-180 that I do struggle to take seriously. The rest of the run just goes into default GFS 12z bulldoze-everything-from-west-to-east mode. The ECM obviously doesn't repeat it's inter-stellar run of yesterday but wow, what a run still! UKMET raw, finally, firmly onside. The ops are only part of the story of course and the ens still a resolute yes still. Factor in the anomaly charts, background signals etc and we are now looking 90%+ for a continental feed (of some sort) next week. A south Westerly attack will always be a possibility (it has to breakdown at some point!) as we head on through the evolution I suspect, let's watch the trends over the next 3 days or so and see where we are heading but I just do not buy the general 12z FI's, it goes against the anomalies for starters. But that's for later, let's get there first and at the moment it's all looking very good still

[Rinse The Raindrops]

If a major event happens over weekend 15th/16th will be the third time in recent years when this has happen exactly a week before the big day and THAT DAY being quite mild in comparison

[joggs]

Never hear of CFS model mentioned on here, probably a crappy model, but shows a much better setup upto 240

Just gona mention the CFS,what a run untill xmas ha ha ha

[TAFKAP]

<rant>The only downgrade today has been some the complete tosh posted on this forum since the 12zs rolled out. Yes it's a model discussion chart and I can excuse some people new to all of this getting over-excited when a chart isn't as good as the one from 6 hours earlier and taking things at face value but there are some seasoned posters who just seem to ruin it for everyone with their constant inaccurate comments that from what I can see are based only because their area is not looking as good as it was looking on the last model run. Let's be objective because this is far from set in stone but this?</rant>

There's obviously no telling some but if I can get through to those new to all of this, forget all about "It's a dry run, no snow!!", "the 850s are not as low on this run!!", "argghhh the -5 isotherm hasn't moved as far south at +144 as 6 hours ago!!", "Oh no! It's a NE, not an E flow!!" honestly, with the onset of an easterly, it will drive you to the point of insanity on preceeding model runs as they always and without fail switch about all over the place as we hone in. And lastly, don't measure a GFS run up against anything else than the GFS from 24 hours earlier, if not, you may as well measure it up against another model frankly.

Anyway... as far I'm concerened it's a big upgrade on yesterday's 12z's and offered these beforehand I want have snatched it in a blink. Why? Because we are 24 hours closer and it's still game on. NO major spoilers have entered the fray!

The GFS is another great run that continues the ride to a cold Easterly but then goes on to offer up a crazy trough extension at about T-180 that I do struggle to take seriously. The rest of the run just goes into default GFS 12z bulldoze-everything-from-west-to-east mode. The ECM obviously doesn't repeat it's inter-stellar run of yesterday but wow, what a run still! UKMET raw, finally, firmly onside. The ops are only part of the story of course and the ens still a resolute yes still. Factor in the anomaly charts, background signals etc and we are now looking 90%+ for a continental feed (of some sort) next week. A south Westerly attack will always be a possibility (it has to breakdown at some point!) as we head on through the evolution I suspect, let's watch the trends over the next 3 days or so and see where we are heading but I just do not buy the general 12z FI's, it goes against the anomalies for starters. But that's for later, let's get there first and at the moment it's all looking very good still

This is the best post in the model thread for the whole day.

[Paul]

Locking this in a bit to start a new one ready for the 18z to roll.

[I remember Atlantic 252]

If a major event happens over weekend 15th/16th will be the third time in recent years when this has happen exactly a week before the big day and THAT DAY being quite mild in comparison

Well, thats not exactly a week before the big day? and big day in 2010 was my coldest ever day, -5.1C max, although uppers were warmer

[Frosty.]

So..it looks like becoming very cold and blocked until mid month at least, the thing to say about this chart is it will be completely different when the time comes, in my opinion the cold block will become very strong for the uk and will be hard to break down, the general consensus is for retrogression to greenland and a probable northerly beyond the easterly with a blocked atlantic.

[Harsh Climate]

''don't measure a GFS run up against anything else than the GFS from 24 hours earlier''

I disagree lancia, 24 hours is a long time model watching! I think it's just best to look at them all and try and find a trend that may be emerging. And the trend that has certainly emerged since this time yesterday, we have moved a fair bit away from the apocalyptic ECM last night and the gfs 12z is less good than previously.

I'm not viewing that as final, but you have to be honest and measured in describing what you see. Anyone with any real experience model watching would tell ya that.

That said, who's to say we might get another snow fest from tonights ECM and that could be a start of a new trend to awesome charts again

Edited December 6, 2012 by Harsh Climate

[Jonan92]

So far none has mentioned the biggest difference in the medium range between GFS and ECM .

In the gfs the atlantic low is very well blocked and the energy is moved around the GH

Therefore, there is no low moving towards Iberia at t144

On the other hand, the ECM shows that low moving towars Iberia

[Downburst]

I am a bit concerned people are assuming the 500mb anomaly charts are infallible. They are not. Last night I mentioned we'd get this reaction today. It is of course one or two "experienced" posters that are ruining this thread for anyone who wants to know anything other than will it snow or not. For the very vast majority it will not. That is almost a fact and will be a fact end of next week. Last nights charts were isolated and the coming runs will continue to deviate from them. It will be colder than average by a very big margin next week and some eastern areas in UK and Ireland especially in the north will get some snow before I suspect a break down form the south. BTW, where is the massive and permanent High over Greenland certain to be here by now in the 500MB charts? 10 days ago it was a certainty?

[Paul]

Locking now - new thread open in 2 mins.

Here it is:

Edited December 6, 2012 by Paul