General Model Output Discussion

[Coast]

OK, back to Model Output discussion........

[PB22]

Back to the models, and a look at the GFS ensembles shows the operational was a mild outlier towards the end of the high resolution run (up to T+180), whilst the control run was the coldest option on the table for T+180!

The ensemble graphs show the operational was a mild outlier early in FI, with most going for a return to cold conditions by the 20th towards the south:

http://www.wzkarten...._London_ens.png

http://www.wzkarten.de/pics/MT8_Manchester_ens.png

Not so keen further north, which suggests an easterly incursion for the south on most of the ensemble members:

http://www.wzkarten....berdeen_ens.png

Edited January 12, 2010 by Paul B

[TEITS]

Keep an eye on that mean around the 20th to see if a dip occurs as other members follow suit.

Dip is even more noticeable on the 12Z than the 0Z/06Z.

http://www.wetterzentrale.de/pics/MT8_London_ens.png

Very promising trend and lets hope this dip continues.

[Tom D]

I've been looking through the 12z GEFS ensembles and have to say there's about 75% bringing a weak easterly to us as a high pressure ridge joins the block giving us a much colder feed from the E/SE. The other 25% (including the operational) don't take that ridge as far north, somewhat squashed by the low pressure to our northwest and leave us with a southwesterly airflow, with temps around average.

http://91.121.94.83/modeles/gfs/run/gfs-0-108.png?12

http://91.121.94.83/modeles/gfs/run/gfs-0-180.png?12

http://91.121.94.83/modeles/gens/run/gens-0-1-108.png?12

http://91.121.94.83/modeles/gens/run/gens-0-1-180.png?12

On the control not sure how long that easterly would last as there's a potent low awaiting in the Atlantic.

[bluearmy]

the dip in the ens around the 20th is the result of the cold pool that develops in the lee of the southerly tracking lows which then get caught up in the se flow around the east scandi block. it shown on a few op runs over the past couple of days. in general the ens dont bring it across as it tends to get shoved back east with the 'resurgent atlantic' at this point. however, at this range it could easily affect us more severely if the block proves that bit stronger. the extended ecm ens also show this cold grouping at this timescale with few runs above zero degrees. the london ecm ens are also cold for a couple of days at this time so it appears that there is decent agreement on a window for a upper cold pool advecting west later next week. something to keep your eyes on then.

[rich1]

Dip is even more noticeable on the 12Z than the 0Z/06Z.

http://www.wetterzen..._London_ens.png

Very promising trend and lets hope this dip continues.

they havent always been up to much in recent times but is interesting that the ensemble mean does suggest the cold will not be away too long

ECM could be of some interest this evening, if its anything like its equivalent yesterday then next week could be interesting

as it is the charts look on the face of it to be a 'stuck in the middle' scenario, as we have seen this winter, mild weather has struggled to impose itself and even in the short range there are room for differing evolutions still

[Thundery wintry showers]

Yes but as I just said sometimes you can't take what the models say in F.I as gospel. Personally when I look at the models I enjoy trying to figure out whats likely to happen and see what errors the models are making. Remember back in Nov 27th when I said an E,ly was on the way for Mid Dec? I was accused of ramping and misleading members and the contents of many posts were similiar to yours above!

If you need to rely on the models then fair enough. However I shall continue viewing the models and adding my own interpretation. For example many think the UKMO +144 might be disappointing but if a +168 existed then the UK would be experiencing a cold SE,ly. Hopefully the 12Z ECM will be similiar to the UKMO at +144 and show this SE,ly at +168.

There has to be a middle ground between "anything goes" (which puts many people off posting as they have to wade through lots of opinionated one-liners to get to any well-reasoned posts) and elitism.

What's wrong with asking people to try to minimise the extent to which personal preferences cloud their views of the models? It's another of those things that can't be avoided, but can be helped, and if we all shrug our shoulders and say, "that's life", then ill-informed hopecasting will be more normal among the model output discussion threads. On the other hand, if we make an effort to be as objective as we can, the threads will on average be rather more constructive. Bias happens, but can be kept to a minimum.

This does not suggest that the less knowledgeable shouldn't post in here- far from it, doing so is a good way to enable the less knowledgeable to become more knowledgeable through learning from the discussions one is involved in. After all, once upon a time I was one of those less knowledgeable contributors as far as model outputs were concerned.

[weather eater]

I have to say I'm with John on this, I don't think its a case of John asking all posters to be technical. What he's asking for is for people to be objective, not just treat every run as the literal truth or just looking for runs that support a preset idea that the poster wishes to transpire. There is strong case for splitting the model thread to pre 144hrs and post 144hrs IMO. It often seems to me to be the extended outlook/trends discussions that get people agitated. We have seen this over the last few days, the overwhelming trend over that period has been to keep the block to our east and us in a run of SWlys giving milder conditions than of late, however some people seem to be determined to see something else as the predominant trend, seizing on any output that supports a retention of the cold whether its the odd run or ensemble member.

We all of course know that FI output will change but its funny how some can only see this when FI shows mild, as soon as its switches to cold it becomes a possible trend. Its a difficult problem some posters just don't have the knowledge to make a balanced judgement, so its is really important in my book for the more knowledgeable to inform as objectively as possible. Especially those that are held in high regard by many members, some of whom seem to hang on their every word, we see so many posts saying stuff like XXXX what do you think of this or YYYY how do you see this developing.

[Frosty.]

http://91.121.94.83/modeles/gens/run/gens-0-1-168.png?12

Cold heading back on the control

Yes please

I know this phrase is being used a lot at the moment but it really is on a knife-edge, it won't take much of a westward shift in the modelling for the uk to enter the freezer again but the odds are probably 70/30 against a return of the bitter arctic cold we have enjoyed during the majority of the past month, it's been great fun.

[Winter Monsoon]

Sorry John but im going to have to speak my mind.

Im getting fed up with your constant moaning and general lack of respect for members on here. Your posts always seem to suggest that all members posts must be technical, scientific and you show a lack of respect for members who do otherwise. Guess what John this isn't a forum for professional Meteorogists as this forum consists of many members whose knowledge of Meterorology varies hugely.

Lets be honest John beyond +168 and you know very well that the pattern suggested by the models isn't always going to be right. The trick of forecasting with these models is knowing whether the pattern being suggested is plausible or not. If not then what is the likely pattern.

So lets drop this attitude please John, otherwise members will be put off from posting on this thread in fear of another John H tantrum!

Omg bit harsh. I havent been around here that much as im pretty new but what i have noticed is John does seem to be more....realistic and grounded.... However you have at times been the most biased posters on here. Not wishing to start an argument but i feel that the above wasnt called for.

And seeing as you speaking your mind ILL speak mine.

Im still waiting for your forcast using your own personal methods that you have used since you were 10 that has never let you down, you posted this earlier today at 11:26am

I would assume an easterly will appear in your forcast as it pretty much does every time. Im also going to assume that your forcast will be localised to your area as it pretty much does most of the time.

Just because a member wishes for a more scientific approach to some of the posts on here which im assuming your personal weather predicting methods that you have used are not....doesnt mean that you should post the above. In fact if you had that much of a problem with John theres such a thing as a PM and not saying stuff like that in this forum and then try and justify that statement accusing said member of possibly driving new member like myself away or prevent them from posting when its posts like yours that do the most damage.

Im sorry but it ticks me off when people deem fit to do the washing in public. After all i have been on the net for a very very very long time and have seen what things like this can lead too.

So rant over. Sorry if this lowers the mood but hey.

[Thundery wintry showers]

Back to the models, and a look at the GFS ensembles shows the operational was a mild outlier towards the end of the high resolution run (up to T+180), whilst the control run was the coldest option on the table for T+180!

The ensemble graphs show the operational was a mild outlier early in FI, with most going for a return to cold conditions by the 20th towards the south:

http://www.wzkarten...._London_ens.png

http://www.wzkarten.de/pics/MT8_Manchester_ens.png

Not so keen further north, which suggests an easterly incursion for the south on most of the ensemble members:

http://www.wzkarten....berdeen_ens.png

Interesting. The GFS and UKMO operationals have backed away from that easterly, yet the GFS ensembles are showing much greater support for it- quite a few of them drop below -10C 850hPa for both London and Manchester, so the possibility of sunshine and snow showers returning from the east next week is not yet out of the question. Probably still about 30% chance in my view, but that still leaves 70% chance of us staying in a no-man's land with close to average temperatures.

The ECMWF could go either way- but if it shows operational and ensemble support for that easterly then things will look pretty interesting.

[cooling climate]

There has to be a middle ground between "anything goes" (which puts many people off posting as they have to wade through lots of opinionated one-liners to get to any well-reasoned posts) and elitism.

What's wrong with asking people to try to minimise the extent to which personal preferences cloud their views of the models? It's another of those things that can't be avoided, but can be helped, and if we all shrug our shoulders and say, "that's life", then ill-informed hopecasting will be more normal among the model output discussion threads. On the other hand, if we make an effort to be as objective as we can, the threads will on average be rather more constructive. Bias happens, but can be kept to a minimum.

This does not suggest that the less knowledgeable shouldn't post in here- far from it, doing so is a good way to enable the less knowledgeable to become more knowledgeable through learning from the discussions one is involved in. After all, once upon a time I was one of those less knowledgeable contributors as far as model outputs were concerned.

Could you tell me and the other members what happened to the competion at the end of Nov where the

winning member was to get free subscription on netweather extra either for a month or the winter.

I bumped the thread a couple of times but heard nothing.

By the way I am a fence sitter as I can see both points of view.

Edited January 12, 2010 by cooling climate

[TEITS]

I would assume an easterly will appear in your forcast as it pretty much does every time. Im also going to assume that your forcast will be localised to your area as it pretty much does most of the time.

You are obviously new on here as my posts discussing the models are focussed on the UK rather than my own location. The only time I concentrate on my location is in the regional threads.

Have to say it does annoy me with comments like yours. I spend many hrs posting on this thread and if I concentrated on every region I would be here all day. Why don't you make a post discussing all regions and see how long this takes!

P.S Only forecasted two E,lys this winter and they were mid Dec, recent cold spell!

[weather eater]

Yes please

I know this phrase is being used a lot at the moment but it really is on a knife-edge, it won't take much of a westward shift in the modelling for the uk to enter the freezer again but the odds are probably 70/30 against a return of the bitter arctic cold we have enjoyed during the majority of the past month, it's been great fun.

Hi Karl I'm not sure you're odds of 70/30 are much of a knife-edge, a blunt one maybe. In truth there's always a scatter on the ensembles, some colder some milder, I do feel however that the overwhelming trend is to keep the block to our east. It could well be that this will change, but I think there is little support for this from the models at this point of time.

[john w]

Interesting reading the posts and debate (I prefer debate to argument) going on in this discussion thread today.

I may be at risk of sounding like a real stick in the mud but there is a technical discussion thread on this board and I do wonder if the type of thread could be expanded upon...i.e Technical discussion stratospheric warming...technical teleconnections....technical physics etc etc.

Model output discussion is for discussing that I suppose and people will always have their certain model. BUT I think model dscussion could have its own section with the technical ones and then guides and links to all the models...netweather...wetterzentrale and all. I know they exist, but to have it all in one consolodated place would be hugely helpful to me in looking at things when away rom work.

Moving to the thread i think bias will always come in to peoples model review. Of the few posts I make in the technical thread I try to be objective I post rarely because I feel technically midget compared to the likes of some. I get the physics and dare i say it I get most the maths, but the experience and reading the models is where I am not so good and I hate to say it but Im petrified of making a wrong post...exemplified when people then quote your wrong post in their footers....so I tend to stay very quiet (my membership since 06 and lack of posts exemplifying this). I do however make reasonable contribution to the ski thread mainly because its 'abroad' and its more on a 1 to 1 with Julian who posts in there.

It sounds crazy this but i really think if netweather.tv wants the enthusiasm to remain then writing some very good guides to models, charts and meteorology in general would be good place...they could be beginner to advanced and cover all facets of a main meteorology book that an academic may write. There are some exceptionally talented people on here and if a good learning section could be produced I think everyone would understand he charts much better and look at the predictions (which is what they are) much more objectively.

On that basis I understand John H's sentiments entirely (and perhaps we are not used to them as he has more time to see the pain of poor posts now he is notesenior forecaster).

Im going to struggle to review the models so I am going to say this:

The prediction was for models to do badly this week and this remains the case, a check on local forecasts reveals different temps and outputs every time you visit the page. The Meto are consistantly saying it will remain cold...at work... which in my eyes signals ideas they havethat their model (and the ones they review) are perhap over doing the mild.

J

[Winter Monsoon]

You are obviously new on here as my posts discussing the models are focussed on the UK rather than my own location. The only time I concentrate on my location is in the regional threads.

Have to say it does annoy me with comments like yours. I spend many hrs posting on this thread and if I concentrated on every region I would be here all day. Why don't you make a post discussing all regions and see how long this takes!

P.S Only forecasted two E,lys this winter and they were mid Dec, recent cold spell!

Yes i am new here and to be honest john has been a very good read i have learnt alot of him. Also you i have learnt alot of you and yes you have been spot on with the easterlies. Im not asking for region by region forcasts, however there has to be some kind of balance to posts. So im not going to continue with this. I will appologise though for my earlier out burst TEITS.

[Magadan]

Interesting reading the posts and debate (I prefer debate to argument) going on in this discussion thread today.

I may be at risk of sounding like a real stick in the mud but there is a technical discussion thread on this board and I do wonder if the type of thread could be expanded upon...i.e Technical discussion stratospheric warming...technical teleconnections....technical physics etc etc.

Model output discussion is for discussing that I suppose and people will always have their certain model. BUT I think model dscussion could have its own section with the technical ones and then guides and links to all the models...netweather...wetterzentrale and all. I know they exist, but to have it all in one consolodated place would be hugely helpful to me in looking at things when away rom work.

Moving to the thread i think bias will always come in to peoples model review. Of the few posts I make in the technical thread I try to be objective I post rarely because I feel technically midget compared to the likes of some. I get the physics and dare i say it I get most the maths, but the experience and reading the models is where I am not so good and I hate to say it but Im petrified of making a wrong post...exemplified when people then quote your wrong post in their footers....so I tend to stay very quiet (my membership since 06 and lack of posts exemplifying this). I do however make reasonable contribution to the ski thread mainly because its 'abroad' and its more on a 1 to 1 with Julian who posts in there.

It sounds crazy this but i really think if netweather.tv wants the enthusiasm to remain then writing some very good guides to models, charts and meteorology in general would be good place...they could be beginner to advanced and cover all facets of a main meteorology book that an academic may write. There are some exceptionally talented people on here and if a good learning section could be produced I think everyone would understand he charts much better and look at the predictions (which is what they are) much more objectively.

On that basis I understand John H's sentiments entirely (and perhaps we are not used to them as he has more time to see the pain of poor posts now he is notesenior forecaster).

Im going to struggle to review the models so I am going to say this:

The prediction was for models to do badly this week and this remains the case, a check on local forecasts reveals different temps and outputs every time you visit the page. The Meto are consistantly saying it will remain cold...at work... which in my eyes signals ideas they havethat their model (and the ones they review) are perhap over doing the mild.

J

Great idea re the model guides... It would be a real help to getting novices up to speed on the more technical matters.

[BLAST FROM THE PAST]

I expect the Met Office extended outlook will catch up tomorrow as it seems somewhat at odds with the output.

UKMO 12Z very similar to GFS 12Z at T+96:

And not too different at T+120:

Those low heights over Greenland will certainly not help future prospects for cold weather returning. :winky:

I don't support that view, even though it may be right. Looking at the UKMO charts I see the important feature is the LP near biscay at t120. I wouldn't be suprised to see Higher pressure build up behind it looping over to connect with the big Russian HP extending NW. I think that is a real sign of the jet possibly ready to kick south.

Yes t144 shows this potential development

BFTP

Edited January 12, 2010 by BLAST FROM THE PAST

[phil nw.]

Taking GFS Ens. for Warks. in isolation and tracking the mean.

http://charts.netwea...arwickshire.png 850pha.

http://charts.netwea...arwickshire.png 2m temps.

http://charts.netwea...arwickshire.png percip.

http://charts.netwea...arwickshire.png air press.

Milder for the weekend then rather cold but not a repeat of the recent low temps.

Pressure fairly high going forward with little percipitation.

The picture very much tells me we remain on the edge of the block but without severe cold.

A slight dip in temps. around the 20th but it doesn`t last.

Further out there are as many milder runs as colder ones so no clear trend yet.

If i may just say i have no problem with posters weather preferences but in this thread links to charts or other output that supports a bias should be provided.

I believe that`s what John meant.

Hopecasting does not add value in a model discussion thread.

Edited January 12, 2010 by phil n.warks.

[MR EXTREMES]

You are obviously new on here as my posts discussing the models are focussed on the UK rather than my own location. The only time I concentrate on my location is in the regional threads.

Have to say it does annoy me with comments like yours. I spend many hrs posting on this thread and if I concentrated on every region I would be here all day. Why don't you make a post discussing all regions and see how long this takes!

P.S Only forecasted two E,lys this winter and they were mid Dec, recent cold spell!

its cool eye you posts are always valid as much as the next dont bite just do ya stuff mate:drinks:

as for the models theres alot of fine tuning that needs doing i dont think we will have a clear picture until the sw attack thats happening right now has run its course.

theres a strong indication that the alantic is gearing up but also signs that the blocks want to put up a fight with us stuck in the middle atm it seem the alantic is going to win out in the shorter term but with colder air not to far away.

from what i can see none of the models suggest a blow tourch outlook and 50/50 on chances of a return of cold,

but we wont see a solid trend until the teleconnections move forward.

i reckon before jan is out we will see a return of the beast,

and with a chance feb could be a suprise for us all even gp,

but i do take notice of many posters in here either it be mild or cold one of thease will be the outcome but i already got my idears of winter 09/10 totally wrong lol.

the models are a mess and perhapes rocking the model thread boat:drinks:

Edited January 12, 2010 by badboy657

[TEITS]

Yes i am new here and to be honest john has been a very good read i have learnt alot of him. Also you i have learnt alot of you and yes you have been spot on with the easterlies. Im not asking for region by region forcasts, however there has to be some kind of balance to posts. So im not going to continue with this. I will appologise though for my earlier out burst TEITS.

I apologise aswell. Im having a bad day as some might be able to tell!

ECM at +144 is showing why I thought the UKMO had potential. You can see the LP system going under the block with both models being very similiar at this timeframe. However look at +168!

http://www.wetterzentrale.de/pics/Recm1681.gif

If the models continue with this trend then in a few days time I shall share my little secret. Like I said earlier some will be amazed and most probably laugh!

[Andy H]

Can i ask a question? i follow this thread with great interest, but the thing i want to know is this winter so far we really have been spoilt with all the snow so far and cold temps, normally at this time of year we are looking for our first snow, there is talk of getting milder or a slight increase of temps, IF we had not had the snow and cold temps we have had recently would there be more excitement about what the models are showing for after this weekend?

[BLAST FROM THE PAST]

ECM at +144 is showing why I thought the UKMO had potential. You can see the LP system going under the block with both models being very similiar at this timeframe. However look at +168!

http://www.wetterzentrale.de/pics/Recm1681.gif

If the models continue with this trend then in a few days time I shall share my little secret. Like I said earlier some will be amazed and most probably laugh!

Dave I agree..see my post a couple above. UKMO would IMO develop into the same as ECM at 168.

I think even at T120 the ECM shows a bump over the channel, I think that will be more of a feature come then and is the first of an undercutting pattern. Thgis will be a quick developing pattern, a temporary blip for now with another week of cold to come next week.

BFTP

Edited January 12, 2010 by BLAST FROM THE PAST

[nick sussex]

Good agreement this evening for a cut off low at 144hrs which could well be the trigger for another shot of colder air. The GEFS ensembles show the operational gfs run a clear mild outlier for the 20th to the 23rd for London, most of the members bring in much colder upper air. The ECM at 168hrs delivers the colder upper air once again! It's a developing situation but for now IMO the trend is for a short milder interlude followed by a return to colder conditions.

I think decision day looms tomorrow, in these situations with growing GEFS ensemble support we need to see the operational GFS run go with one of those colder ensemble members.

Edited January 12, 2010 by nick sussex

[Thundery wintry showers]

Hi Karl I'm not sure you're odds of 70/30 are much of a knife-edge, a blunt one maybe. In truth there's always a scatter on the ensembles, some colder some milder, I do feel however that the overwhelming trend is to keep the block to our east. It could well be that this will change, but I think there is little support for this from the models at this point of time.

I'm not sure I agree there- while the GFS and UKMO operationals have dropped it, the GFS ensembles show more support than with any earlier GFS run, and it looks (from the ECM T+168 chart) as if the ECMWF operational is going to go for it.

Only 70-30 against in my view.