Model Output Discussion 1st January 2014-06z onwards.

[The Eagle]

 

 

 

 

jeez eagle, if that disappointing, where have you been for the past six weeks, siberia ?

 

 

 

I expected an advance on the 00z ensembles. It's actually backward somewhat though that could also be explained by some rouge member runs. It's not bad per se. Plenty of potential. I'd be wary of op run outliers. We have been in far better situations before at more comfortable timeframes only to find things fall apart very quickly. Be hoping to avoid that situation.

 

The evolution is fragile.

[nick sussex]

Are these not the postage stamps?

 

http://www.ecmwf.int/samples/d/inspect/catalog/samplers/banner/mean_sea_level_pressure_and_temperature_at_850hpa!168!pop!od!enfo!enplot!2009112700!!/

They're back, thanks Daniel, they disappeared and I wasn't able to access them for ages. Okay I'll retract my stinges accusation at the ECM now!

 

PS semi retracted they only go upto T120hr now!!! lol

Edited January 8, 2014 by nick sussex

[Gaz1985]

After "that ECM" in Dec 2012 I think I'm going to take the model output of projected cold with a large pinch of salt until at least Sunday, as we all know things can come crashing down with a big bump.

[weather eater]

As for the ensembles I never look at them, but the fact that some (or even a significant number) of them don’t buy into an easterly should be no surprise, it would be absolutely remarkable if they all supported the op not to mention deeply suspicious.

[Nick F]

They're back, thanks Daniel, they disappeared and I wasn't able to access them for ages. Okay I'll retract my stinges accusation at the ECM now! PS semi retracted they only go upto T120hr now!!! lol

They're still stinges, as they used to go out to T+168.

[Team Jo]

Evening folks!

 

Edge of your seat stuff tonight, whether you like cold or not!

 

Can I just politely ask that, given there are 865 of us online at present, that you try and keep your posts to the models. There are lots of other good places to discuss the emotive part of the current runs, which lives here:      Model Banter, Moans and Ramps Winter 2013/14    

 

There are also the Regionals, which are great for asking the questions you're too afraid to ask - (Will it snow in my back garden, will the trains all stop, has this come from the US freeze, etc)

 

Finally, if you have a one-line statement, then there are the Status updates you can use to Rant/Ramp in a couple of sentences.

 

I really don't like deleting posts at all, so think about what you're typing and if it lives in the most appropriate thread, eh?

 

This is an exciting time, and some ups and downs are possible, but I do ask that we all to to keep it civil, as excited and passionate we all feel; as this turnaround has shown, anything can and will happen!

 

Jo x

[That ECM]

After "that ECM" in Dec 2012 I think I'm going to take the model output of projected cold with a large pinch of salt until at least Sunday, as we all know things can come crashing down with a big bump.

Sensible to be cautious of course but it's different this time. ECM was basically on it own then, not so this time.

[nick sussex]

The reason for some of the ensembles not getting to an easterly is as clear as night and day at T72hrs and T96hrs, some of those will develop a positive tilt to the troughing, some complications with shortwave energy but overall to believe those non easterly ensembles you have to believe that the ECM operational run is wrong at just T72 and T96hrs.

 

Again this is all to do with the upstream pattern but can anyone tell me the last time the ECM operational run was wrong at T72hrs! I 'd advise everyone to look at those ensemble postage stamps at T72hrs and T96hrs.

Edited January 8, 2014 by nick sussex

[snowking]

Most encouraging chart of the night for me is this:

Let's worry about surface temp/850 temp/precipitation when it comes in to closer timeframes.

For now let's focus on the trends...and the trend there is pretty solidly behind winds from an Easterly direction across the near continent.

Small steps.

SK

[IDO]

The Dutch extended ensembles:

 

It suggests about 50% say yes to an easterly. Of those that say yes, there is strong support for this to be a short snap for Holland, so probably shorter over the UK.

 

The good: The control and the op both give us cold for 3-4 days, assuming similar for the UK.

 

This ties in with all the tweets from the weather experts. Most are saying that at the moment it's looking like an average January cold shot. All of them clarifying their thoughts that it remains very uncertain that the easterly will happen, though it has improved on today's output.

 

Clearly it could go either way but lets be positive.

 

 

[Downpour]

I think people have to separate out what the UKMO will say publicly and what they think internally at their HQ, theres no point them making a big song and dance about it now. With easterlies and indeed with any cold weather in the UK theres always a level of uncertainty but overall the trends are that way this evening. I think we can blame the recent media for printing rubbish and over the top hysterical headlines, especially when even the word colder or easterly are mentioned! So perhaps they don't want the Daily Express printing yet more rubbish!

The Office have had serious problems with the tabloid press in recent winters, often taking the step of publicly debunking hyperbole from the likes of the Express. I don't blame them for being cautious. I suspect they are looking at Friday before committing.

[Captain Shortwave]

The reason for some of the ensembles not getting to an easterly is as clear as night and day at T72hrs and T96hrs, some of those will develop a positive tilt to the troughing, some complications with shortwave energy but overall to believe those non easterly ensembles you have to believe that the ECM operational run is wrong at just T72 and T96hrs.

 

Again this is all to do with the upstream pattern but can anyone tell me the last time the ECM operational run was wrong at T72hrs! I 'd advise everyone to look at those ensemble postage stamps at T72hrs and T96hrs.

lols, this would eclipse the December 2012 debacle for the entire model operational suite to be wrong at just 3 days out.

It won't happen. I believe 

[Cheshire Freeze]

The Dutch extended ensembles: eps_pluim_tt_06310 (1).png

 

It suggests about 50% say yes to an easterly. Of those that say yes, there is strong support for this to be a short snap for Holland, so probably shorter over the UK.

 

The good: The control and the op both give us cold for 3-4 days, assuming similar for the UK.

 

This ties in with all the tweets from the weather experts. Most are saying that at the moment it's looking like an average January cold shot. All of them clarifying their thoughts that it remains very uncertain that the easterly will happen, though it has improved on today's output.

 

Clearly it could go either way but lets be positive.

 

Yes we have 2 hurdles......the first one is actually getting the easterly, the second one is somehow managing to extend the spell. ECM not keen atm (as you can see from the ensembles) but all we can do is monitor and see if we start to see some form of extension in them.

[weather eater]

Just to touch on the ensembles again, the operational run is the best guess based on the data, the ensembles are the same data tweaked (maybe Twerked), at the moment the ECM operational has support from most of the other models operational runs, I’d start worrying if any of those start to pull up an alternative evolution and not worry about rogue ensembles.

[Timmytour]

Sensible to be cautious of course but it's different this time. ECM was basically on it own then, not so this time.

 

I'm not so sure it was on its own. My recollection was that it was one of the last to come on board and then, when it did so, it was go go go for the Beast From the East.

Only then the GFS started to go the other way.......followed slowly by the others.

Which makes me somewhat nervous about the upcoming GFS 18Z

[LomondSnowstorm]

The reason for some of the ensembles not getting to an easterly is as clear as night and day at T72hrs and T96hrs, some of those will develop a positive tilt to the troughing, some complications with shortwave energy but overall to believe those non easterly ensembles you have to believe that the ECM operational run is wrong at just T72 and T96hrs. Again this is all to do with the upstream pattern but can anyone tell me the last time the ECM operational run was wrong at T72hrs! I 'd advise everyone to look at those ensemble postage stamps at T72hrs and T96hrs.

I think the comparatively massive swing overnight tells us how finely balanced the margins are here, which is why some perturbations will go wrong early - the MoE is so small that even a very slightly different starting condition gives a no go at a very early stage in the run. Fortunately, all the ops have us on the right side of this where it really matters which is why an easterly should be the favoured solution. However, given such a small MoE, the ECM could conceivably be wrong. At +72 (at least wrong enough to derail things somewhat). By tomorrow we really should have a much more coherent set of ensembles as by that point there's really no going back on the first step, and then all we have to worry about is details and potential shortwave issues, both good and bad.

[The Eagle]

 

I'm not so sure it was on its own. My recollection was that it was one of the last to come on board and then, when it did so, it was go go go for the Beast From the East.

Only then the GFS started to go the other way.......followed slowly by the others.

Which makes me somewhat nervous about the upcoming GFS 18Z

 

 

IIRC it was the GFS ensembles that crumbled and the op runs ended up being increasing outliers. Quite a few refused to acknowledge that things were going a stray just because the op runs were showing a dream scenario (consistently as well). But even that was at a much closer time frame than now. I'm cautiously optimistic. 

 

Anyway hopefully we see the 18z move more toward the ECM in the early stages. I'd like to go to bed happy instead of flustered.

[SMU]

At this stage only the GEM supports sustained cold, however that's in the minority of outcomes versus the GFS & ECM ensembles -

 

Still, that doesn't really come into play until the track of the sliders at 168 is resolved.-  I have at this stage discarded the operational run from the ECM tonight post 168 due to the sliders track being somewhat out of kilter with expectation & what we have seen historically- infact I have never seen a low park itself there -

 

Another round of models to fizz over tomorrow- I think the ECM ( just like the poor 12z last night) will correct on the 00z to the correct sliding scenario.

 

Confidence in the models cold scenario tonight 85% all blended UKMO, GFS & ECM- ECM colder solution at 120 favoured due to historic last minute corrections SW, however the slider scenario from the GFS then seems the best horse to back post that-

Milder solutions- flatter low in the atlantic 15%-  no major model suggests this just some of the rogue ECM & GFS ensembles. At this stage discount all the mild outliers.

 

longevity at this stage- 3-5 days pending change to longer cold depending on upstream developments...

 

S

Edited January 8, 2014 by Steve Murr

[Long haul to mild]

As usual, as soon as a cold spell becomes a reasonable likelihood, people start telling us that it will only last for two days blah blah blah.

Ian F's post earlier was very valid; IF we get a cold setup, it is likely to be a lot harder to shift that the models suggest; and almost certainly much tougher than the tired and predictable reset to zonality shown on the GFS 12z.

The irony is that those who are trying to predict the end are the same ones saying it may not even happen to begin with! If they are correct in that we can't be sure of what is happening in 5 or 6 days, then their predictions of what is going to happen in 10 days time are not worth the screen they have been typed on to!

Edited January 8, 2014 by Chalk Serpent

[nick sussex]

I think the comparatively massive swing overnight tells us how finely balanced the margins are here, which is why some perturbations will go wrong early - the MoE is so small that even a very slightly different starting condition gives a no go at a very early stage in the run. Fortunately, all the ops have us on the right side of this where it really matters which is why an easterly should be the favoured solution. However, given such a small MoE, the ECM could conceivably be wrong. At +72 (at least wrong enough to derail things somewhat). By tomorrow we really should have a much more coherent set of ensembles as by that point there's really no going back on the first step, and then all we have to worry about is details and potential shortwave issues, both good and bad.

If it was just one model you could perhaps say well its rogue but every single operational model has a similar set up at least for the amplitude of the trough at T72hrs, if you look at the verification stats for them all to be wrong at that timeframe would be unprecedented since we've been viewing the outputs on the net.

 

The issue might be more whether its a clean easterly or more ese/se because of the trough disruption being closer but the drama just refuses to go away!

[Summer Sun]

Looks like Gibby is too busy to post his update so here it is

 

Good evening. Here is the report on the 12 noon outputs from GFS, UKMO, GEM, navgem and ECM for today Wednesday January 8th 2014 taken from http://www.norton-radstockweather.co.uk/Model-Analysis(2859336).htm

 

All models show a small depression moving NE across England and Wales tonight and out into the North sea tomorrow. Rain , particularly over Wales will move further NE with only showery bursts in the South. Tomorrow will see a weak Westerly flow with a ridge of High pressure giving a dry and brighter day tomorrow with some welcome sunshine. On Friday the ridge will be replaced by a weakening front crossing East over Britain with some rain for a time. Late in the day and on Saturday an area of High pressure will cross Southern Britain with a Southerly flow following behind on Sunday ahead of a new area of rain spreading slowly in across Southern and Western Britain later in the day.

 

GFS then shows next week with cold weather setting in quickly with rain turning to snow in places next week especially in the South as Low pressure slides away SE. High pressure to the NE and SW link up across the North late in the run and slips SE cutting off the cold feed and allowing milder air to return from the NW late in the run on Westerly winds.

 

UKMO tonight shows High pressure over the Norwegian Sea with Low pressure having slid away SE from Southern Britain leaving slack pressure gradients over the UK next Tuesday with rather colder and quiet weather through the day with some rain or sleet possible at times.

 

GEM shows quite a wintry development next week as pressure rises to the North and NE while pressure stays low over Southern Britain and the near continent with a resultant Easterly flow across the UK with bands of rain, sleet and snow for all in cold conditions and some accumulated snow in places later.

 

NAVGEM is broadly similar, sinking High pressure towards Scotland late in the run but maintaining a cold Easterly flow late next week from it's introduction early in the week. Some snow showers will no doubt occur almost anywhere over the UK but perhaps the South and East most favoured.

 

ECM tonight shows Low pressure close to or over the UK early in the week with rain at times. This slides SE along with new centre's following a similar path later in the week and bringing the growing trend towards cold weather with fresh to strong easterly breezes with rain turning to snow in places later in the week. This weather type persists into next weekend when High pressure is centred over Sweden although on this run the axis and orientation of the airflow around it brings less cold SE feed up across Britain in relatively dry weather as Low pressure stays well away to the SW. 

 

The GFS Ensembles tonight show a very mixed picture with a lot of spread between the members. At the coldest phase some members don't go cold at all keeping things milder and wet but the majority do show at least a cold period before the effects of this become eroded by the Atlantic return later in the run. There are precipitation events throughout the run and not all of them will be of rain for a time.

 

The Jet Stream flow currently undergoing a cessation of it's powerful West to East feed near the UK of late remains mixed over the coming few days as slacker synoptics occur near the UK. Next week the flow crosses Southern Europe under cutting the High pressure to the North. However, there is also a trend then for the Jet flow to strengthen once more late in the run to over ride the sinking High pressure.

 

In Summary the pattern remains consistent on the weather turning colder next week. How long it lasts is anyone's guess and will no doubt change over the coming days outputs model to model. However with Low pressure in the mix from all models and Easterly winds likely to be blowing over the UK from the East from before midweek a spell of cold weather with snow in places is a strong possibility for the first time this Winter.

Edited January 8, 2014 by Summer Sun

[East_England_Stormchaser91]

 

I'm not so sure it was on its own. My recollection was that it was one of the last to come on board and then, when it did so, it was go go go for the Beast From the East.

Only then the GFS started to go the other way.......followed slowly by the others.

Which makes me somewhat nervous about the upcoming GFS 18Z

In GFS we trust. 

 

Lets just hope it doesn't do a David Moyes on us!

[jvenge]

As usual, as soon as a cold spell becomes a reasonable likelihood, people start telling us that it will only last for two days blah blah blah.Ian F's post earlier was very valid; IF we get a cold setup, it is likely to be a lot harder to shift that the models suggest; and almost certainly much tougher than the tired and predictable reset to zonality shown on the GFS 12z.The irony is that those who are trying to predict the end are the same ones saying it may not even happen to begin with! If they are correct in that we can't be sure of what is happening in 5 or 6 days, then their predictions of what is going to happen in 10 days time are not worth the screen they have been typed on to!

 

Well, I'd love some cold weather, although I'd rather not have it last too long, as I need to travel around a lot :-)

 

However, this is the model discussion thread. Although posts by Ian and a few others explain the apparent end of the cold, it is still in the models. It might be negative, unreliable and down right unlikely, but it is still shown and is therefore fair to discuss. I think Ian also said it isn't a done deal either.

 

Going by posts here, there are going to be a lot of depressed people if it is a snap and I'd like to think a few posters are just wanting to prevent that ;-)

 

So, be it 3 days or 7 or so weeks, let's just enjoy whatever comes. As long as it isn't flooding, of course ;-)

[Ali1977]

Lets see what the pub run does, if its as good as the 12Z then this will be great, its always a worry if the pub run starts downgrading potential cold spells.

[Matty M]

The Dutch extended ensembles: eps_pluim_tt_06310 (1).png

 

It suggests about 50% say yes to an easterly. Of those that say yes, there is strong support for this to be a short snap for Holland, so probably shorter over the UK.

 

The good: The control and the op both give us cold for 3-4 days, assuming similar for the UK.

 

This ties in with all the tweets from the weather experts. Most are saying that at the moment it's looking like an average January cold shot. All of them clarifying their thoughts that it remains very uncertain that the easterly will happen, though it has improved on today's output.

 

Clearly it could go either way but lets be positive.

One thing i must say ( and not be a negative nelly ) but there is a large consensus in the ENS for it to turn milder after the 5-7 day window with almost no runs having the temps below zero after this spell.

 

Obviously very far out but not what you would like to see.