Model Output Discussion:

[snow drift]

If we don't get a cold spell next week then questions need to be asked yet again about the Met Office and their forecasts

I think the Met Office get way to much stick on here. If most of the posters on here had given a forecast for the coming weeks then it would have changed on a daily basis from, very cold and snowy to mild and south westerlies.

Reality is that the ground in the middle is likely to be the outcome.

If you are constantly looking for extreme weather you are, for the most part, going to be constantly disappointed. The people I feel for are the ones who can not decipher the models for themselves and then hang on the words of the posters. This must drive them to distraction.

The models have struggled and continue to struggle with this mild air cold air battle. I don't think that this has been resolved although as time goes by I would put it at advantage mild.

[karyo]

Thats very nice of you Karyo

Well this is always the problem in these set ups where a western based negative NAO is forecast, as you can see once the elongated trough appears on the scene running sw/ne and the block to the east sinks its a very slow moving pattern until theres an upstream change.

I do wonder what you said earlier regarding the MJO moving back towards phase 6 is causing these changes, although this by itself might not be totally to blame perhaps its tipped an already knife edge pattern the wrong way in terms of cold, although the forecasts expect it to move towards phases 7 and 8 I'd much rather see its actual position.

If the MJO is to blame then this can be easily solved if it moves as the forecasts suggest. Mind you, we both know how inaccurate they have been!

Regarding the west based -NAO, am I right in thinking that once it sets up, it doesn't tend to easily move east/become east based?

Karyo

[Solar Cycles]

I think the Met Office get way to much stick on here. If most of the posters on here had given a forecast for the coming weeks then it would have changed on a daily basis from, very cold and snowy to mild and south westerlies.

Reality is that the ground in the middle is likely to be the outcome.

If you are constantly looking for extreme weather you are, for the most part, going to be constantly disappointed. The people I feel for are the ones who can not decipher the models for themselves and then hang on the words of the posters. This must drive them to distraction.

The models have struggled and continue to struggle with this mild air cold air battle. I don't think that this has been resolved although as time goes by I would put it at advantage mild.

Off topic I know, but I'll defend the MetO when it comes to their short/medium forecasts. Also they can't be judged on their forecast yet, it may well prove to be right!

[Long haul to mild]

I think the game is up on this one, the Atlantic trough looks highly likely to extend too far East and a West based NAO, if that's where we are headed usually sees Low pressure on a constant SW to NE track with HP over Southern Europe.

There are still issues to be resolved but any easterly looks a very slim chance and I would expect the METO to change their 6 to 15 dayer when they update tomorrow lunchtime.

Going by the model runs you would expect a different 6-15 day forecast tomorrow but I think we've been saying that pretty much every day since the UKMO turned against the Easterly last week but still they continue to forecast cold weather next week every time they update.

I don't think this is over yet; I have never seen such model swings; last night the ECM had freezing E'lys in the long term outlook, and today completely different.

I am seen as the weather guru in my office (although my limited knowledge pales into insignificance compared to many experts on here) and after my success in predicting the December cold spell and the snow at Easter 2008 (both thanks to the posters on this forum! ) , I keep getting asked what is going to happen next week. Every day I have to tell them something different. Come on models, get a grip, I have people to impress!

[nick sussex]

If the MJO is to blame then this can be easily solved if it moves as the forecasts suggest. Mind you, we both know how inaccurate they have been!

Regarding the west based -NAO, am I right in thinking that once it sets up, it doesn't tend to easily move east/become east based?

Karyo

Yes you're right thats why I nearly passed out when I saw the GFS and UKMO! The only other time this winter I can remember when we were worried about the western negative NAO it didn't actually happen, I think this was before Xmas when the models toyed with this idea but held the block just far enough east, this was the time where the GFS in particular kept throwing low pressure too far north towards the UK because it pulled the Scandi trough too far west. This time there seems a better consensus that the west neg NAO is likely, however blocking is very much evident right across the Arctic regions but that Atlantic trough just looks determined to spoil the party.

It's a bit like one of those trailers for a movie, it's a race against time to save the UK from imminent mild mush! We've got just about enough time for the models to be overplaying the energy eastwards off the trough but we're almost at the point of no return!

[No Balls Like Snow Balls]

These models just don't make sense, even though most are saying milder now, you have the BBC and the Met both still saying it is going to get colder next week!!, it would not surprise me at all to see the models switch back to a Easterly over the next few days. I have never known anything quite like it!!

[Optimus Prime]

a PRETTY GOOD fax CHART;

[chris78]

This may be in the wrong thread so mods feel free to ..... Anyway, with the models swinging about so much there must clearly be a signal or two that are acting as 'fulcrums' around which the models swing. The guys and girls that run and interpret these models must be even more stressed and bewildered than the good folk on this forum. Do they never communicate with the real world amateur forecast people? Do they have no communication channels to pass information on? I know that hugely complex terrafloppy supercomputers run the numbers but real people set the models and parameters before hitting the 'go' button for each run. Why do we never hear about their headscratching - only the wildly swinging outputs. If the economic forecasts (which use similarly, unimaginabley huge computers running Monte Carlo simulations) struggle then we get to hear why. I am puzzled as to why professional forecasters sit in a black hole that allows no information beyond the event horizon... Or am I missing some vital piece of the puzzle? As a complete novice - quite likely!

absolutly brilliant ..what would be wrong with the facility for, say a model managment team (i dont know - i dont have to name them) to provide a statement with each run...even if it was...we dont know why its so mad either.

I suppose the problem would be it would involve someone putting their neck on the line....they probably see their role as providing output not comenting on the chances of it coming off. I still feel some notes on each run may be helpful.

[billy]

a PRETTY GOOD fax CHART;

Isnt that yesterdays chart ?

[karyo]

a PRETTY GOOD fax CHART;

Yesterday's!

[Bobby]

Yes the new FAX charts will be out about 10:30.

[johnholmes]

absolutly brilliant ..what would be wrong with the facility for, say a model managment team (i dont know - i dont have to name them) to provide a statement with each run...even if it was...we dont know why its so mad either.

I suppose the problem would be it would involve someone putting their neck on the line....they probably see their role as providing output not comenting on the chances of it coming off. I still feel some notes on each run may be helpful.

possibly seems a good idea to us with nothing better to do than watch the models. However it would require someone to spend time doing just that when I suppose they are expected to get on with their main job.

We simply see the raw ouput that the centres then use to advise their clients and no doubt they are told how they view any run.

NOAA do tell the world if you want to know-simply go to their web site and read their short and longer term comments on how they feel the models are performing.

Edited February 2, 2010 by johnholmes

[snow drift]

Yesterday's!

It may be yesterdays. What he said was, it is "a pretty good fax chart" no reference to Date!!!!!!!

[Duane S.]

If the MJO is to blame then this can be easily solved if it moves as the forecasts suggest. Mind you, we both know how inaccurate they have been!

Historically the MJO forecasts are pretty dire but I have found that for the past 2 to 3 weeks they have actually been pretty accurate. Most model forecasts corectly showed the march to phase 5 to 6 and have been predicting the stalling/slight regression in phase 7 for a while as well. Firm agreement to trundle on into phase 8 in about a week or so's time which can only work in our favour I would have thought.

Edited February 2, 2010 by s4lancia

[chris78]

possibly seems a good idea to us with nothing better to do than watch the models. However it would require someone to spend time doing just that when I suppose they are expected to get on with their main job.

We simply see the raw ouput that the centres then use to advise their clients and no doubt they are told how they view any run.

NOAA do tell the world if you want to know-simply go to their web site and read their short and longer term comments on how they feel the models are performing.

Thanks johnny I forget the models primary purpose isnt to entertain 'us with nothing better to do than watch the models' as you say im sure they give those extras to paying clients

Edited February 2, 2010 by chris78

[in the vale]

possibly seems a good idea to us with nothing better to do than watch the models. However it would require someone to spend time doing just that when I suppose they are expected to get on with their main job.

We simply see the raw ouput that the centres then use to advise their clients and no doubt they are told how they view any run.

NOAA do tell the world if you want to know-simply go to their web site and read their short and longer term comments on how they feel the models are performing.

The UKMO is an Executive Agency of the MoD, and as such is (partly - accepted) funded by us as Taxpayers. I work in the government, and I know we are all under immense pressure to communicate more with the public. I am not demanding something extraordinary here - just a thought. I know this does not apply to other (purely commercial) model providers, but surely communicating with the general public is never a bad thing? (OK I can think of many exceptions, but the weather is not one of them!)

[karyo]

Historically the MJO forecasts are pretty dire but I have found that for the past 2 to 3 weeks they have actually been pretty accurate. Most model forecasts corectly showed the march to phase 5 to 6 and have been predicting the stalling/slight regression in phase 7 for a while as well. Firm agreement to trundle on into phase 8 in about a week or so's time which can only work in our favour I would have thought.

Yes, let's hope this move eastwards materialises.

Snowdrift, I know it was not said it was today's fax chart but what is the point to put yesterday's since the models have changed so dramtically since?

Karyo

[Ian Fergusson]

Well, all you cold weather fans, I was listening to Radio Gloucestershire at 6.30 tonight and Richard Angwin (Ian Fergusons buddy) was saying Winters is still lurking, referring to AO and NAO. He said mild until mid next week when easterly will returning and weather looking like it will turn cold again. He specifically made comment about significant snow in these parts.

The models are hiding something.

Ahhh - but are they?? More likely, they're just all-over-the-shop! Again....

As I noted on my blog (and I'm still reluctant to shift my somewhat ambivalent assessment at this juncture), there's still a chance of this being a distinctly cold end-game but it's likely to be a mid-next-week transition to anything distinctly chillier here in the West (weekend transition to something more SE'ly is likely later into the weekend in the SE/E, at least if latest UKMO GM is to be trusted).

The flip-flop (and clearly for some, frustrating) nature of recent deterministic model runs is all thanks to the varying degrees of ridge amplification and its eastwards progress next week, plus it's noteworthy how the spread of EC EPS and Met Office MOGREPS solutions both for the weekend and into next week show a much greater spread than the norm. But hey-ho, such is the nature of this scientific discipline and especially at such essentially 'sci-fi' range peering into the future.

The UKMO' latest detailed standpoint on the 6-10 / 10-15 day period (cited partially below and due to be updated at midnight - I do stress this!) says it all, in my mind, in terms of the continued uncertainty - hence my own low-grade enthusiasm over all this until we get into the weekend and see how it all develops thereafter.

Cold? Probably. Very cold? Possibly (but by no means a done deal). Snowy? Well, based on the currently declining heavy PPN signal, maybe nothing significant on the cards, at least for lowland S. British Isles.... but then hey, the detail remains so very elusive that anything is possible.

In the view of UKMO Ops Centre earlier today:

"Significant uncertainty extends into this period. Favoured scenario is (snip) on unsettled side and often rather cold, perhaps cold..... (snip)........the balance of EPS output suggests low pressure continuing to dominate over the Atlantic next week, leading to a more SE’ly type developing bringing frontal zones erratically into the UK, leading to occasional snow risk in the north and east".

Anyway, let's see what the next (flip-flop?) runs hint towards.

[johnholmes]

thanks for that update and insight into the Senior man's mind, I'd love to have access again to all that but never mind it seems it cannot be.

[Buxton Codge]

Thanks Ian for the update. So it would seem next week will be more of the same i.e atlantic fronts pushing in with some hill snow but generally mild in the south and west

http://www.knmi.nl/exp/pluim/Data/PLUIM_06260_NWT.png

ECM Ens show only a small risk of cold conditions

[Ian Fergusson]

Thanks Ian for the update. So it would seem next week will be more of the same i.e atlantic fronts pushing in with some hill snow but generally mild in the south and west

Well, for a while at least.... but here's their expert view for at least a section of next week (replicating what you'll doubtless read elsewhere from UKMO on the web) - - So OK, as widely alluded to on this forum - it's clearly got potential to develop into something a good deal colder but I've yet to see this being strongly signalled by the Exeter folks in their briefings over the past 24-36hrs. HOWEVER and I know I'm always stressing this - - this below views were expressed at midday and so I'll await their expert opinion again when I'm back into the office at 0400 tomorrow. Perhaps it'll have shifted one way or another.

3. Days 8-10 - Tuesday to Thursday: Often rather cloudy. Spells of wet weather likely to affect many W/SW’ern regions throughout, this PPN then making erratic E/NE’ward progress whilst weakening but also turning to sleet and snow at times in N/E/Central regions at times. Some E/NE’ern parts perhaps largely dry throughout. Temperatures largely near normal to the W/SW, elsewhere mostly rather cold."

[Snowstorm1]

Thanks Ian for the update. So it would seem next week will be more of the same i.e atlantic fronts pushing in with some hill snow but generally mild in the south and west

http://www.knmi.nl/e...M_06260_NWT.png

ECM Ens show only a small risk of cold conditions

A small risk id say it looks like 35% split for cold which is more than a small risk but 65% are on the mild camp.

[January Snowstorm]

Well between GP's comments on the other thread and Ian's above, good news afoot

Perhaps the mother of all model backtracks is looming

[Frosty.]

Perhaps the mother of all model backtracks is looming

That sounds familiar, like sunday and then yesterday, today has seen another shift away from a cold pattern with the uk kind of the sandwich filling, mild air never really taking control but the cold air too far east to make much of an impact so the uk currently looks like seeing temps rise in the coming days to at least near average, maybe milder in the sw and ireland but probably a bit colder in the far north east, nothing wintry on the horizon beyond tomorrow.

[johnholmes]

I suggest that the realistic outlook is that given by Ian from his briefing this morning from UK Met.

Yes they get it wrong, short term and longer term, but they are probably nearer the mark more often than not in their 6-15 day outlooks.

I know it gets stick at times but no one seems prepared to actually test it properly to see how near it is and how often.

I would wager its about 75% correct at 6 days maybe a bit higher and near 65-70% at 15 days but stand to be corrected if anyone has actual data to prove otherwise.

Its terribly easy to be critical but very very much more difficult to be constructively critical I find!