Winter Model Output Discussion 01/02/2013 12z onwards

[A.J]

ECM..........remember..............December. No I didn't.

thanks for that, I now have a strained retina and it wasn't even worth a 'like'!

Well, here's hoping the ECM verifies at T144, I could do with a few days off work snowbound!

[lord stratus]

Hat off Steve your right, it looked like an eastward correction to me at first glance. I have to say I'm starting to come round. Can't believe the ECM has stuck to its guns on so many runs now! I will either love or hate the ECM in a few days time. Is there a middle ground between the GFS and ECM? I'm struggling to see what it would look like?

You'll hate it!

[Frosty.]

yes i understand the synoptics side of it but the temps for feb still look on the high side to be fair.Anyway heres hoping for one more last wintry spell before months end

I think the cold and snow risk will upgrade in the short term, there is that warm depression core heading south but I do think there will be some wet snow around which could bring some accumulations, especially to higher ground.

[johnholmes]

How about we have a touch of reality and realism in here from a few of you?

How newcomers are supposed to pick up what is happening when there is so much niggling going on I do not know.

For their benefit, on Net Wx free version, link below is a link showing how the different models are portraying the weather out to T+240 (for those that go that far).

http://www.netweathe...modelcomp;sess=

A tip Do NOT try to put surface detail on beyond about T+96 no matter what any model shows. It will not be like that at T+00. Look at the black line on each chart to see if the shape it has is the same on each model. If it is then even at T+240 one can have a reasonable amount of confidence in what the upper air, which is what that black line is showing, being near enough as it is shown. If there is much difference then step back 24 hours until it does look the same on each chart.

For instance, the 12 output, showing at the moment (as of 2016 Sunday 3 February=it will update with the next model outputs), at T+240 they are not really alike in the west of the chart. ECMWF has a trough which GFS does not hence quite different weather will develop as a result of that.

Try the T+216 hours, and again there is a difference, this time its the its the position of the ridge, one has it over Europe the other west of the UK.

So try the T+192 = still a difference in the position of that upper ridge

The 168=nope, one has a flattish flow the other has not-put in very simple terms

T+144 and not that far out but some differences so to the T+120 and it is fairly close on the major two but it comes from the T+96 which GFS showed quite a ridge with ECMWF not as marked one, so down to the 72 then the 48 and the 24 hour, and all of those charts, looking initially at the upper air using the black line are pretty close.

That then allows us to take a closer look at each model and what it is suggesting for the surface.

If one does that say using the 00 and 12z runs it will give a far more balanced view of what is likely in the time scales I've dealt with.

Of course you could become a jh convert and largely use the 500mb anomaly charts for the longer time scales, that is 6-15 days ahead, T+144 to 240 and beyond!

Hope that helps to show new folk how to have a go at what the models are showing and how much belief we can put in them

One final thing, no matter how clever any of us think we are, old man weather loves to make us look foolish-but it can be fun, but oh why do some of you have to keep having a dig at someone else. pack it in then this forum would be a much friendlier place-honest.

Edited February 3, 2013 by johnholmes

[Canalboy]

You have to ask yourself how many times has the ECM at about 144z-196z been fairly accurate in blocking circumstances and you'd probably find not much, so that's why I'm taking all the recent runs with a dose of salts. It would be a big koo for the model come next monday if we have a slider into the SW and cold advecting west from the continent. But I doubt it.

Looking purely at what the ECM model is showing of course.

A big Koo? That's not the one that Price Andrew courted in the eighties is it?

[damianslaw]

Just need a bit of patience, those slightly below average temps early in the week will fall a few degrees by midweek when the frosts become more widespread, quite a few troughs on the fax charts with a mix of sleet and maybe wet snow depending on elevation, probably northern and eastern scotland and ne england bordering the north sea will have the heaviest snow in the next 5 days as they do best in a straight northerly.

The temperatures progged by BBC are the absolute maximum we can expect, under any showers temps will take a real nosedive easily down to 0 degrees in the north, so whilst many might expect to see 4 or 5 degrees mid week - they may only see such temps for a few minutes at the warmest part of the day and only if there is sufficent lengthy sunny spells.

Temperatures next week will be academic anyway because the wind will make it feel preety much sub zero.

Northerlies in April often don't deliver maxima much higher than 4 or 5 degrees neither.

Highland Scotland is likely to see some very heavy snow in the coming days, expecting many high level routes to be closed with blizzard conditions.

Its going to be one of those weeks of chasing the snow showers.

Back to the models - tomorrow will be an interesting day, either the GFS will fall into line with ECM or vise versa, to see such marked differences continue within the 96hr timeframe would be quite alarming - more likely I suspect they will start to show something which is a mix of both i.e. the trough becoming unstuck as it hits western shores and probably dissapating in situ thanks to building heights to the NE and a bit of a stalemate between the atlantic and continent with the country bang in the middle.

[chionomaniac]

New thread coming soon, please finish off in here.

[Methuselah]

Just need a bit of patience, those slightly below average temps early in the week will fall a few degrees by midweek when the frosts become more widespread, quite a few troughs on the fax charts with a mix of sleet and maybe wet snow depending on elevation, probably northern and eastern scotland and ne england bordering the north sea will have the heaviest snow in the next 5 days as they do best in a straight northerly.

Some patience...By the time that easterly gets here, it'll be 32C with a chance of thunderstorms!

[Captain Shortwave]

I hope Steve Murr gives more of an account about the ECM but here is a quick temperature mean

-6 uppers still cover all but the far South West/Ireland at midday next Monday, hmm

[london-snow]

ECM..........remember..............December. No I didn't.

Yes i remember December very well...

However cast your mind back a shorter period a few weeks back in actual fact.

ECM & to a extent the UKMO v GFS.

Who come back into line eventually proving yet again?

The GFS.

( And yet again in the lead up it showed westward correction as that always seems to be the case with the GFS. )

Who is my money on?

At the moment i would say the UKMO as a halfway house where neither options can be ruled out but the ECM op's cannot be overlooked as it is the best public model available imo.

As for the GFS well its fallen at the final hurdle and is awaiting to be put down by the vet in these types of set ups it is beyond me why people put faith in it. Time after time it says no and time after time it comes whimpering back into line.

[chionomaniac]

New thread here

Closing this soon.