Model Output Discussion - 5th December - 11th December

[Backtrack]

Well that's a start just need the other models to follow.

You're so boring Gavin. No wind, no rain, no snow, no cloud, no nothing but high pressure. Everytime I see your posts it's only when there seems to be a major downgrade, or nothing remotely cold is showing? Frankly it's starting to annoy me.

Back to the models:

Small changes from the 6z to the 12z which shift the center of the LP further South, but bringing down the intensity of the low slightly. A slight relief for NW England, and although I would love to see high winds, I think 100mph gusts would destroy the region.

The ECM drops the low almost completely, but that's because the frames aren't as detailed as the GFS's, and as seen above, the low is still there. I would think it will reappear on the next ECM run.

I do expect the low to shift slightly further North on future runs, an exciting time weather wise coming up. Can't wait!

Edited December 11, 2011 by Backtrack

[bluearmy]

naefs 12z update takes the storm track along the forth/clyde valley. interestingly it also shows a 'smaller' cluster of runs as per the ecm op run option where the storm deepens most as it exits the southeast of the uk.

ecm T240 showed a deepish shortwave astride the uk. naefs at the same timescale has a similar feature to the northwest of the uk. it then develops a whole string of these depressions running west - east to just to the north of scotland. a very mobile and potentially stormy holiday season beckons if that is right. the spreads still show a lack of appetite to build the azores ridge into europe so basically, a continuation of what we've seen so far this month though i suspect a trend to average to cool zonality as opposed to cool to cold zonality as we've had.

[Downburst]

18z rolling out, should be interesting. God knows what arguments it might start though!

The Wetterzentral site BTW. What does it say about people who go to that site that they have those seedy advertising?

[lorenzo]

Persistent and going to be an interesting set of runs tomorrow.. Looking very cold on the thickness charts here, can anything be derived from these as to when the rapid deepening of the low is projected?

Not great with these would appreciate some assistance!

http://176.31.229.22...792452830188686

http://176.31.229.22...792452830188686

[DaBrigg]

One thing to note about the ECM enembles, most of them seem keen to keep the low centre in whatever form it comes reasonably far south. None at all throw it north of Scotland completely. There has been a slight southward shift over the last few GFS runs as well, I believe.

[Liam J]

You're so boring Gavin. No wind, no rain, no snow, no cloud, no nothing but high pressure. Everytime I see your posts it's only when there seems to be a major downgrade, or nothing remotely cold is showing? Frankly it's starting to annoy me.

Back to the models:

Small changes from the 6z to the 12z which shift the center of the LP further South, but bringing down the intensity of the low slightly. A slight relief for NW England, and although I would love to see high winds, I think 100mph gusts would destroy the region.

The ECM drops the low almost completely, but that's because the frames aren't as detailed as the GFS's, and as seen above, the low is still there. I would think it will reappear on the next ECM run.

I do expect the low to shift slightly further North on future runs, an exciting time weather wise coming up. Can't wait!

I agree BT, whilst the ECM is a credible model, if I was a betting man and had just looked at all the 12z suite op runs then I certainly wouldn't be putting my money with the ECM.

I may loose my money but the chances are higher the other way atm, all credit to the ECM if it proves correct, GFS 18z run will be very important...

[johnholmes]

I may loose my money but the chances are higher the other way atm, all credit to the ECM if it proves correct, GFS 18z run will be very important...

why on earth will it be important-its one run-I really do give up on some folk watching every run and the next one is often 'the important...'

sorry but rubbish.

The models as I keep going on about will chop and change, how about someone for a change, check the 12z today with yesterday and heaven be praised the same time tomorrow to see if there is any continuity?

One of the models MAY be correct, or even one of its ensemble members may be correct today, perhaps tomorrow. But watching how any particular run deals with the situation as the count down to whatever event you are interested in would be much more beneficial-honest-but then I only have 20 years actual experience doing it. Of course the professional folk at Exeter will be doing just what you are doing-big difference though-its done realistically and professionally, not hyped up. I dread to think what the hand over at watch change would be like if it followed the same bear garden atmosphere that one often finds in here!

By all means at T+72 perhaps T+96 check each run and compare, compare with the other models but just a touch of realism in here would really help the newcomers learn something.

Edited December 11, 2011 by johnholmes

[Backtrack]

I agree BT, whilst the ECM is a credible model, if I was a betting man and had just looked at all the 12z suite op runs then I certainly wouldn't be putting my money with the ECM.

I may loose my money but the chances are higher the other way atm, all credit to the ECM if it proves correct, GFS 18z run will be very important...

It's all eyes to the 18z, if this drops the idea, then the ECM will be in with a shout. If not, we can probably discard the ECM.

[cyclonic happiness]

why on earth will it be important-its one run-I really do give up on some folk watching every run and the next one is often 'the important...'

sorry but rubbish.

The models as I keep going on about will chop and change, how about someone for a change, check the 12z today with yesterday and heaven be praised the same time tomorrow to see if there is any continuity?

One of the models MAY be correct, or even one of its ensemble members may be correct today, perhaps tomorrow. But watching how any particular run deals with the situation as the count down to whatever event you are interested in would be much more beneficial-honest-but then I only have 20 years actual experience doing it. Of course the professional folk at Exeter will be doing just what you are doing-big difference though-its done realistically and professionally, not hyped up. I dread to think what the hand over at watch change would be like if it followed the same bear garden atmosphere that one often finds in here!

By all means at T+72 perhaps T+96 check each run and compare, compare with the other models but just a touch of realism in here would really help the newcomers learn something.

I do agree on most of what you say John, but I do enjoy some of the 'beer garden atmosphere' sometimes, especially when the models are showing a big freeze.

I suppose that with something as potentially serious as the storms next week, perhaps we should pay more attention to the facts, if only to arrange travel plans and shoring up loose tiles and the like?

I'm not sure what to make of the ECM today to be honest, it would be an amazing downgrade, but perhaps would save alot of lives if it were not to come to pass?

[Liam J]

why on earth will it be important-its one run-I really do give up on some folk watching every run and the next one is often 'the important...'

sorry but rubbish.

The ECM has the data fed in later than the other 12z outputs? So the GFS 18z will have the most recent data programmed for this later run which may follow where the ECM left off?

People do and will continue to look at each model output, you will never stop this no matter how many times you try and prevent them.

If somebody wants to view each output from the models and comment then let them, as this is the model output discussion is it not?

Edited December 11, 2011 by Liam J

[Geordiesnow]

why on earth will it be important-its one run-I really do give up on some folk watching every run and the next one is often 'the important...'

sorry but rubbish.

Its perhaps "important" because the next run(18Z) is another 6 hours of data closer to the event and it might give some indication on what might happen regarding this deep low pressure system. Your idea of comparing today's 12Z run to yesterday's 12Z run is nonsence, seeing as a whole 24 hours of data is filtered in and we see huge differences that it does not tell us an great deal really.

Having said that, the ECM 00Z run will perhaps be more important than this upcoming GFS 18Z run as the GFS might stick to it guns but it does not always mean that this afternoon's ECM output suddenly becomes a total nonsence.

[Matty M]

Ummmmmmmm the nerves are jangling.

The upcoming low looks very complicated and is changing its make up run by run. 18z different to the UKM and ECM at this point with this so exact windspeeds during the early week are still up in air.

[Downburst]

It's all eyes to the 18z, if this drops the idea, then the ECM will be in with a shout. If not, we can probably discard the ECM.

This is not the case, this system is FI for a couple of reasons and one can't discount the ECM 12z at all no matter what GFS says. We are looking at a system potentially developing that is very fine tuned and lots can happen. I am getting sucked in here, but I do know 24 hours out can still make major changes to the actual reality.

[Matty M]

18z shos the storm less developed at 78hrs, perhaps its heading like the ECM........?

[DaBrigg]

The 18z has the secondary low centre from Tuesday's storm further south and west, bringing a second batch of strong winds into Ireland then Northern England instead of Scotland on Wednesday. Quiet a difference for some of us at only t+60.

[Backtrack]

This is not the case, this system is FI for a couple of reasons and one can't discount the ECM 12z at all no matter what GFS says. We are looking at a system potentially developing that is very fine tuned and lots can happen. I am getting sucked in here, but I do know 24 hours out can still make major changes to the actual reality.

Sure it can, but when you have pretty much every model in agreement that something is going to happen, you're not likely to follow a run that shows that particular scenario disappearing.

This is the reason I think the ECM will reintroduce the system come tomorrow.

[Matty M]

it is not interacting with the jet as much and has signs of developing that second cente behind it at T84hrs like the ECM

[Liam J]

GFS looks like it could follow the ECM with a much less developed depression so far.

[Matty M]

GFS looks like it could follow the ECM with a much less developed depression so far.

It's not injesting that cold air from the north like the 12z did, its racing northeast.

[Downburst]

96hrs it's all different to ECM. However the ECM has introduced enough uncertainty to remind us this is not gospel.

[weathe20]

Seems like a weeker affair on the 18z already at +87

[Backtrack]

As I posted in the regional discussions earlier, I had my hunches that this low could sink further South, and although this was only a hunch, it seems to of paid off.

The low is much shallower, and would provide nothing but a seasonal gale.

Unfortunate really, I was hoping for a good old storm.

[johnwirral]

Looks like the SW taking the hit on the 18z

[Liam J]

Much weaker on the 18z and further south, from hurricane force storm to a pretty standard depression with strong to gale force winds into SW and along the channel.

Still this is 4/5 days away so it was always subject to large changes, this could easily be brought back as significant storm over the coming days. Last Thursdays storm didn't really look much about 3 days in advance until the models blew it up.

Edit just seen frame 108, severe gales over N and E England, down to 955hpa.

Edited December 11, 2011 by Liam J

[nick sussex]

The ECM has the data fed in later than the other 12z outputs? So the GFS 18z will have the most recent data programmed for this later run which may follow where the ECM left off?

People do and will continue to look at each model output, you will never stop this no matter how many times you try and prevent them.

If somebody wants to view each output from the models and comment then let them, as this is the model output discussion is it not?

I agree

Generally speaking I think it's perfectly reasonable to compare all four GFS runs within 144hrs and even more so within 96hrs the latest run even allowing for some data bias should give a good indication seeing as it will have newer data.

This whole debate regarding comparing only the same run per day comes up every year, I would say that the lower resolution though is generally a waste of time in terms of run to run comparison seeing as the GFS often throws out four different scenarios in the one day.