Model Output Discussion

[snowmadchrisuk]

This is exactly what I have been constantly saying as well. I have been incredibly impressed with the consistency of the model, like no other I have ever seen in the run up to a cold spell, without qusetion. But of course, at this stage, you can only be impressed with consistency, not yet verification.

Hopefully though we will be lauding it as the king of models in a week's time and not writing it off before it has even begun!

All very intriguing to see how this pans out...

We can verify the pressure rise though , it showed this a good 7-10 days out .

[Geordiesnow]

Quote of the Century if your talking about how wrong it is. GFS has been the most consistent it has ever been in all my years of model watching . ECM has been chopping and changing every single run.

I would not say it's been chopping and changing every single run but it has been more reluctant to show cold shots, although i'm sure it won't take much for the ECM to change into a more colder and snowier set up. At the same time, it won't take much for the GFS/UKMO to change from a good set up to not such a good set up.

Although consistency helps, it does not mean anything, if there is one change in the pressure atmosphere then that can change everything. If the ECM has got data issues then we have to be a bit more vigilant of what it is showing but it does not mean it's wrong.

Hopefully we will have some agreement tomorrow and hopefully the agreement will be positive for snow fans.

[Cecil Hogmanay Melchett]

I was really hoping GP moght post his thoughts this evening. ;(

We are in the midst of the biggest crisis on NW and our glorious leader has deserted us.

Gp,steady the ship dude,panic is taking over.

[Snowyowl9]

So many pages to get through,had to skip some.

Lets finish tonight on a high

[Richie V]

In spite of an excellent GFS 18Z Operational, Control, Parallel Run & Ensemble Mean... I would say be weary, very weary because it's very, very uncommon for ECMWF to backtrack as such a close timeframe to realtime.

The differences are stark this evening, even from T+72..

Again, as what I said earlier, past letdowns have learned us that GFS can backtrack in one run...

As many have said, the 00Z's will be absolutely crucial, along with tomorrow's 12Z's..

In light of every available source of model guidance tonight, including FAX charts, I would lower the potential for a snowy outbreak to 30% & no higher..

It will turn cold, increasingly cold, but whether it will be sustained or snowy is really open to question.

I fear that the ECMWF 12Z run will be nearer the mark, but I hope & pray that GFS is correct.

I think everyone should lower expectations slightly just in case an overnight reversion to ECMWF 12Z does take place.

Yes, All our biggest fears are that the ECM is like the quiet guy sat in the pub in the corner minding his own buisness and you have the three loud louts at the bar (GFS, GFS para and UKMO) screaming, swearing and threatening the bar staff. ECM has had enough, gets up takes the big three outside and gives them a bloody good hiding.

[weather eater]

This is exactly what I have been constantly saying as well. I have been incredibly impressed with the consistency of the model, like no other I have ever seen in the run up to a cold spell, without qusetion. But of course, at this stage, you can only be impressed with consistency, not yet verification.

Hopefully though we will be lauding it as the king of models in a week's time and not writing it off before it has even begun!

All very intriguing to see how this pans out...

To be honest I'd rather have its consistency even if it fails to verify, than the Yo-yoing we have seen from the ECM, if only to calm some members nerves. I really don’t have any expectations of the models, they are forecasting tools and have to make judgements for the future using increasingly out date data as each run progresses, they are frequently wrong, about all kinds of synoptical evolutions, it’s just times like this when many people start to really notice it.

[snowmadchrisuk]

I would not say it's been chopping and changing every single run but it has been more reluctant to show cold shots, although i'm sure it won't take much for the ECM to change into a more colder and snowier set up. At the same time, it won't take much for the GFS/UKMO to change from a good set up to not such a good set up.

Although consistency helps, it does not mean anything, if there is one change in the pressure atmosphere then that can change everything. If the ECM has got data issues then we have to be a bit more vigilant of what it is showing but it does not mean it's wrong.

Hopefully we will have some agreement tomorrow and hopefully the agreement will be positive for snow fans.

I have to GFS charts below : the first one is the GFS chart for Saturday taken from the 18z run on the 4th of December , the second chart is taken from tonights 18z GFS run the 10th for Saturday , If this isn't verification of how well the GFS has done , I don't know what is.

This chart has gone from +180 to +36 and is almost identical.

Night all , Chris .

[Frosty.]

So many pages to get through,had to skip some.

Lets finish tonight on a high

Yep let's finish on a mega greenie high, a thing of beauty and a stonking N'ly to follow the trough south. Hopefully the ecm tomorrow will not show high pressure glued to the BI and will have it being pulled in a north westerly direction and give us a welcome taste of winter following a rubbish autumn.

[Neilsouth]

Fantastic 18z ensembles;

http://91.121.93.17/pics/MT8_London_ens.png

[Thundery wintry showers]

In spite of an excellent GFS 18Z Operational, Control, Parallel Run & Ensemble Mean... I would say be weary, very weary because it's very, very uncommon for ECMWF to backtrack as such a close timeframe to realtime.

I agree with most of what you say re. caution, but the ECMWF backtracked on a number of occasions last winter at a similar timeframe. In particular it had a tendency to bring in the Atlantic far too quickly. On the other side of the coin, it occasionally threw up spectacular NE'lys out in FI as well, though no more so than GFS.

The ECMWF is, generally speaking, the most accurate model in the world in the T+96-T+144 range but it did have a progressive bias during last winter- we will have to see if that is rearing its ugly head again here.

[Richie V]

I have to GFS charts below : the first one is the GFS chart for Saturday taken from the 18z run on the 4th of December , the second chart is taken from tonights 18z GFS run the 10th for Saturday , If this isn't verification of how well the GFS has done , I don't know what is.

This chart has gone from +180 to +36 and is almost identical.

Night all , Chris .

This for me is POST OF THE WEEK, thank you chris for this. Yes thats severe consistancy for ya. Gfs = top of the class and a gold star.

Night all

[NorthantsSnow]

GFS ensembles are bizarrely close together in the mid term. I was expecting more spread given what the ECM is showing.

Overall I'm very confused by tonight's output. GFS very bullish about what it's showing but ECM still says no! Back in the morning to see if the 00z runs make the situation clearer.

[Duane S.]

Soon we will be getting to the inevitable point when two notable things happen...

1) Some get so wrapped up on wanting continual upgrade after upgrade shortly after the 'event' has started that they forget to actually 'enjoy the moment'.

2) We get the "it's an upgrade!" "no it's a downgrade!!" scenario when Bill from Dartmoor and Ben from Scotland argue with each over over whether or not a certain run/chart is an upgrade or a downgrade. The futility of these arguments between people often living at opposite ends of the country never fails to amuse/amaze me.

[Snow Queen one]

This is the model thread chaps. Although there is a lull in the charts at the mo i feel that your comments should not be in this thread. how about using the ignore button for Ian or report him then something can be done. Personal comments such as those may make you feel better but should be directed to the relevant person via PM's.

Thanks this is done with my SACRA hat on by the way mods.

[snowray]

Yes, All our biggest fears are that the ECM is like the quiet guy sat in the pub in the corner minding his own buisness and you have the three loud louts at the bar (GFS, GFS para and UKMO) screaming, swearing and threatening the bar staff. ECM has had enough, gets up takes the big three outside and gives them a bloody good hiding.

Hehe, loving that! Nice romantic idea, but I home that he gets battered to pieces!

Must say the 18z and its parallel are looking good enough for me, certainly someone will inevitably end up with much egg on their face.

The ECM 00z is the turning point in all this i feel, can it stay out there on its own for three runs on a trot???

Most runs on the whole are slightly different from about T72, so anything can still happen, as JS has said, it will be down to the wire!

[Paul_1978]

Reading this topic is an extraordinary experience, particularly at times like this. I have only a limited ability to read the models so look to this topic for guidance, and tonight I appear to have been told the following:

1. big freeze still on

2. big freeze might be on

3. big freeze not as big as first thought but still quite big

4. big freeze now "downgraded" to "even larger teapot big freeze", ie not much of a freeze at all

5. cold snap

6. cold snap-ette

7. cold up north but not down south

8. cold down south but not up north

9. ECWMF is the most reliable model

10. ECMWF model is not to be trusted tonight

11. ECMWF is not be trusted in this set up, whether tonight or not

12. GFS is not to be trusted in blocking set ups

13. GFS has been consistent and therefore is to be trusted (nothwithstanding 12)

14. It will get cold shortly

15. ECMWF data is missing tonight according to our new friend from Holland

16. Our new friend from Holland is clearly on the money (although we are all asking each other whether we know if he/she is right or not)

Is it any wonder we are probably all a little frazzled.....

When I was at secondary school second year in 1978 I used to sell weather forecasts to my class mates for 5p. I based them on a presusre chart in the daily paper and by looking out of the window of the science lab towards the West. Surprisingly I had a few sales. Most often I was roughly right but living then near the Severn estuary it was pretty reliable to say it was about to rain. My approach would have been useless in this current scenario so please let's have some measured and considered views (that I can nick and sell on at 2009 prices). Thanks.

AS

Now that is the post of the week. I too am a lurker on these threads, and you get to know which members appear to know what they're talking about and which don't. That's after filtering through all the one-liners of course!

You have summed up exactly how I, and most probably many others feel about what they are reading. It is most confusing sometimes and the info coming out from board members is very different.

However that's the beauty of these boards I suppose, and people have different levels of expertise and different opinions of what's good and what isn't.

I expect us lurkers (and regular posters for that matter) will have to make informed decisions based on what we can best make sense of.

For what it's worth, I'm enjoying the anticipation, and like most others, I'm hoping it doesn't all go t1ts ups. And I may well join many members in bashing one off if we get a sustained wintry and snowy spell

Cheers!

Paul

[Geordiesnow]

Whilst IB posts may have hints of wishing the set up to fail to prove his "christmas pudding" theory, it does not give an excuse to launch some personal attacks on him. If IB thinks the ecm is right and the other models will follow suit, then that his opinion. It's just the complete opposite of most others on here thinking the ecm will back down but there is nothing wrong with that and dare i say it, IB could well be right(not with his christmas pudding theory, just his opinion that the ecm will be closer to the mark).

This thread could be even worst to read by tomorrow morning if IB proves to be right. I have to say i am nervous for tomorrow morning's model runs and if the worst happens then i probably won't come onto the forum but i must say that all the signs(at the moment) point to the GFS/UKMO being closer to the mark.

However know our luck, the ecm will come on board and the GFS or the UKMO will back down. - don't know whether i would laugh or cry at that stage!

[Lewis]

This beauty would bring blizzards in from the North Sea!!!!

I just swallowed my cigarette!

WOW

Absolute belter, 18Z is a wopper of a run,

Would like to thank KoldWeather once again and Thundery W showers for fantastic post's, especially TWS for answering my questions earlier on.

Fingers crossed the ECM and GFS 00Z are ok tomorrow, i may just stay up for it. around 3:30am when it rolls is it not?

lewis

Edited December 10, 2009 by Storm Force Lewis

[peterf]

i apologise for my rant.does that mean i have to mean it

anyway onwards and upwards.

[reef]

Right, enough of all this now. The state of this thread is ridiculous tonight. The team have been flat out this evening and have had to remove over 100 posts of total drivel and still the thread is like a bombsite. Regardless of how some people's posts might infuriate you personal attacks and insults will not be tolerated. If the team think people are purposely baiting others then action will be taken. Until then, keep on topic.

[Yeti]

Soon we will be getting to the inevitable point when two notable things happen...

1) Some get so wrapped up on wanting continual upgrade after upgrade shortly after the 'event' has started that they forget to actually 'enjoy the moment'.

2) We get the "it's an upgrade!" "no it's a downgrade!!" scenario when Bill from Dartmoor and Ben from Scotland argue with each over over whether or not a certain run/chart is an upgrade or a downgrade. The futility of these arguments between people often living at opposite ends of the country never fails to amuse/amaze me.

Then it will be "yes it's a bad run, but it's Christmas/Boxing Day/Christmas hols/New Year's Day so obviously there's missing data".

Extremely varied output tonight; lots of people want to ignore the ECM but despite all the good reasons telling me too there's still a part of me that is convinced it will turn out just like that (i.e. sinking high).

Then there's still the rather large issue of the shortwave which is equally erratic on the models; the 12z wanted to pull it right S and bring the cold air into Europe with the UK too near the high, whereas the 18z keeps it over Denmark and the Netherlands again. Its placement will have quite a big impact on the intensity of the cold spell and tightness of flow.

[reef]

New thread starting in a moment...

[wysiwyg]

Right, enough of all this now. The state of this thread is ridiculous tonight. The team have been flat out this evening and have had to remove over 100 posts of total drivel and still the thread is like a bombsite. Regardless of how some people's posts might infuriate you personal attacks and insults will not be tolerated. If the team think people are purposely baiting others then action will be taken. Until then, keep on topic.

Does that apply to unjustified attacks on the ECMWF just because it didn't agree with all the other models?

[andy_leics22]

I have to GFS charts below : the first one is the GFS chart for Saturday taken from the 18z run on the 4th of December , the second chart is taken from tonights 18z GFS run the 10th for Saturday , If this isn't verification of how well the GFS has done , I don't know what is.

This chart has gone from +180 to +36 and is almost identical.

Night all , Chris .

Superb post Chris, post of the day IMO.

That is a great example of what the GFS is capable of, that is exactly why I like the GFS.

[reef]

New thread.