Model Output Discussion 17th Dec.2013-12z onwards.

[Jason M]

Good ECM 240. Could go either way from this point but an interesting chart and the 192 and 216 are not the worst either.

http://www.meteociel.fr/modeles/ecmwf.php?ech=72&mode=1&map=0&type=0&archive=0

[weather eater]

Good ECM best operational I’ve seen in a while.

Edited December 30, 2013 by weather eater

[Cecil Hogmanay Melchett]

Good ECM 240. Could go either way from this point but an interesting chart and the 192 and 216 are not the worst either.http://www.meteociel.fr/modeles/ecmwf.php?ech=72&mode=1&map=0&type=0&archive=0

Well at 10days away its pretty meaningless to analyse to much,upstream it looks reasonable but loook at that huge area of High pressure across Southern Europe,we need the lows to drop SE,desperately.

[nick sussex]

The sum total of that ECM is I have a concussion after banging my head against a brick wall!

 

Upstream is good, indeed the orientation of the PV looks a good correlation for a ne/e over the UK, as you can see at T240hrs it desperately tries to do that, maybe you might get lucky here but margin for error is always needed in the UK.

 

If people don't want to have to need sedatives to cope with the stress of finding some cold then we need the upstream pattern as is with the troughing over the UK sending more energy east/se, we need a bit more forcing on the pattern near the UK and need some stronger heights to the ne.

 

Overall not a bad trend from the ECM and theres scope for some improvements, a lot needs to go right upstream and its critical that energy phases with the PV and associated low to develop that more amplified wave ahead of it.

[Matty M]

Good ECM 240. Could go either way from this point but an interesting chart and the 192 and 216 are not the worst either.http://www.meteociel.fr/modeles/ecmwf.php?ech=72&mode=1&map=0&type=0&archive=0

 Only going one way at that point! Return to westerlies.

[Man With Beard]

The next two weeks could bring a transition - PV looks to be vulnerable, a near permanent Arctic High - but for cold prospects, the continuing strength of the Canadian PV is problematic - while it's around, we're always in danger of being on the milder side of things.

 

ECM T240 shows how cold could threaten even with the Canadian PV in situ - shame the ECM has tended to overdo amplification in recent times:

 

[bluearmy]

ecm op is in line with the dominant cluster on the 12z gefs at day 10.  a bit of light in the general darkness ???

[Captain Shortwave]

Good ECM 240. Could go either way from this point but an interesting chart and the 192 and 216 are not the worst either.http://www.meteociel.fr/modeles/ecmwf.php?ech=72&mode=1&map=0&type=0&archive=0

Alas we can't develop a Euro trough which means the wedge of heights will sink over the UK. You need a better profile to the north east earlier on, which can split the energy NE/SE and develop a low in the Mediterranean like this mornings run. This one you end up with a stalemate which stalls the trough which means the trough sharpens and elongates whilst remaining in near enough the same location. That in response actually raises heights over southern Europe as the trough digs into the Canary Isles. 

It's pure conjecture though as the models can't agree at even 4 days out on the upstream pattern. At least the ECM and to a degree the GFS offer some hope going forward with some tweaks. But frankly the models seem to being playing with these different heights/ridges like they are pick and mix.

Edited December 30, 2013 by Captain shortwave

[Jason M]

Only going one way at that point! Return to westerlies.

Not sure I completely agree with that. It's certainly a possibility but if you look at the progression of the low near canada from 216 to 240 its going north. Also with a distinct high pressure cell to our NW the jet could easily be deflected SE.A very difficult chart to call tbh.

[lassie23]

Hp across Europe is proving a real pain in the backside again.

 

Euro high and azores high this winter have been misbehaving! They just won't head north.

[Gibby]

Good evening folks. Here is tonight's report on the 12 noon outputs of the NWP for today Monday December 30th 2013.

 

All models show the weather fine for a time tonight as a lull passes East over the UK. Another squally trough feature then moves East over Britain after midnight clearing tomorrow morning to a day of sunshine and squally heavy showers. On New Years Day the weather remains very unsettled with a new Low spinning NE up the Western flank of the UK with renewed gales and heavy rain followed by showers late in the day. The unsettled and windy theme is then shown to continue in one shape or another from all models up to the end of the weekend.

 

GFS then shows the second half of the run with little respite with further Low pressure areas marching in from the West close to Northern Scotland sending rain bearing troughs East across the UK with further severe gales in places and temperatures close to average throughout.

 

UKMO closes the run next Sunday showing Low pressure to the West of Ireland with a strong SW flow across the UK with heavy rain and gales continuing to batter the UK on occasion with showers and sunny intervals in between.

 

GEM tonight shows stormy conditions to start next week before a colder interlude develops with wintry showers as pressure rises from the South with a dry and brighter spell for most in 10 days time, though it doesn't look likely to last long.

 

NAVGEM closes it's run with deep low pressure to the north of the UK with strong WSW winds carrying further rain and shower bands East across the UK in average temperatures.

 

ECM too shows the chance of something rather colder setting up as we move towards the end of next week as Low pressure slows down and fills over the UK as High pressure ridges through the Atlantic, setting up a cell of High pressure just to the North and with lower pressure over Southern Europe there is a chance that the end of tonight's ECM could be the break that many cold fans were looking for.

 

The GFS Ensembles do show some signs of change later in the output as a few members drop into the abyss with regard to cold while others take a more modest approach towards cold late in the run. the net result is another week to 10 days of wet and wild weather before things may turn rather colder and drier.

 

The Jet Stream shows the flow as before through the next week to 10 days with the increased tendency for it to buckle later as the speed of flow of Atlantic Lows is slowed.

 

In Summary tonight I am pleased to say that there does seem to be some light at the end of the recent very long tunnel. There is a lot of wind and rain to get through during the next 10 days but there are tonight better signals for a pattern change later next week as the chance of something rather colder and drier is indicated from more than one source.

[nick sussex]

After my mini tirade re tonights ECM lets think positively here! The small high which looks no match for the PV could develop into a cut off feature here, it all depends whether that energy on the se part of the PV goes se.

 

It has though a low margin for error because the troughing over the UK  has taken so long to fill and disrupt, upstream is favourable, its just trying to get the pattern near the UK to play ball.

[Cloud 10]

ecm op is in line with the dominant cluster on the 12z gefs at day 10.  a bit of light in the general darkness ???

 

Should mean a more amplified NAEFS 12z later on.

[winterof79]

 Only going one way at that point! Return to westerlies.

Please back that statement up with reasoning for the newbies or less well informed

After this point i presume you are referring

http://www.meteociel.fr/modeles/ecmwf/runs/2013123012/ECH1-240.GIF?30-0

http://www.meteociel.fr/modeles/ecmwf/runs/2013123012/ECH0-240.GIF?30-0

[Summer Sun]

Things starting to look better now albeit 10 days away so caution needed but we do have growing signs that the Atlantic train of LP systems could come to an end during the 2nd half of next week

 

ECM

 

 

GEM

 

 

GFS

 

[Jason M]

Please back that statement up with reasoning for the newbies or less well informedAfter this point i presume you are referringhttp://www.meteociel.fr/modeles/ecmwf/runs/2013123012/ECH1-240.GIF?30-0http://www.meteociel.fr/modeles/ecmwf/runs/2013123012/ECH0-240.GIF?30-0

In fairness, he's presumably referring to the jet stream coming off the US. The issue really is where that jet streak goes and that's very difficult indeed to call off that chart. Its a real 50/50 scenario as I could see that developing into a full blown easterly two days down the line. Equally though it's perfectly possible that we would be back to square 1 two days later. Take your pick really.

[winterof79]

In fairness, he's presumably referring to the jet stream coming off the US. The issue really is where that jet streak goes and that's very difficult indeed to call off that chart. Its a real 50/50 scenario as I could see that developing into a full blown easterly two days down the line. Equally though it's perfectly possible that we would be back to square 1 two days later. Take your pick really.

I understood that but thankyou for your explanation.My point was really that it was not going solely one way and it would have been better for some on here to know that.

[BLAST FROM THE PAST]

 

Now that's more like it, will this be the first run of many to show this route this soon?  I think it is onto something here.  For me previous runs have been milder than this, although not real cold its a colder theme and could develop more favourably from there.

 

And not without support ..... a hint from GFS

 

 

 

BFTP

Edited December 30, 2013 by BLAST FROM THE PAST

[The Post-modern Winter]

In fairness, he's presumably referring to the jet stream coming off the US. The issue really is where that jet streak goes and that's very difficult indeed to call off that chart. Its a real 50/50 scenario as I could see that developing into a full blown easterly two days down the line. Equally though it's perfectly possible that we would be back to square 1 two days later. Take your pick really.

In fairness he said "there's only one way from there". No 50/50 caveats stated or suggested. Simply a misleading statement which appears far to often on this forum. How I can come to the same (correct) conclusion as many of the experienced people on here with regards to that chart, considering my very limited exposure to the models, while somebody so accustomed to them can differ from them so much is strange. Really doesn't help with the learning process that so many on here, such as JH, attempt to aid. Charts to back up the statement would help in this regard Edited December 30, 2013 by The Post-modern Winter

[R.P. McMurphy]

 

Now that's more like it, will this be the first run of many to show this route this soon?  I think it is onto something here.  For me previous runs have been milder than this, although not real cold its a colder theme and could develop more favourably from there.

 

And not without support wither

 

 

 

BFTP

[cooling climate]

There are a few posts in this thread showing 10hPa temperature charts from meteociel. Please note that the temperature patterns on these charts do not show the geopotential heights and therefore we cannot comment on the state of the polar vortex at this level from these charts. Therefore we cannot say whether there is a split vortex or not. Currently any strat warming forecasts are very much at the end of FI - yes they are promising, but I feel that we should not get overhyped about these until we something in a more reliable timeframe. Furthermore to that - even if we were to see a SSW then it would be unlikely to occur until the last third of January and any possible cold benefits would only be felt after that date so we are not likely to see any significant strat induced cold options on the modelling for a good while if at all.

 

Perhaps it would be a good idea if we should concentrate on the trop output for a while in this thread and keep the strat charts to the strat thread?

A very strange request from you Chionomaniac considering the great work and time you have put

in to educate posters about the importance of the state of the stratosphere in winter time and the

undeniable link it has with the troposphere and different synoptics seen in the troposphere and

on the NWP model output.

 

I think all cold winter weather lovers should be very pleased with the GFS 12z run from a

stratospheric point of view.

Edited December 30, 2013 by cooling climate

[Jason M]

In fairness he said "there's only one way from there". No 50/50 caveats stated or suggested. Simply a misleading statement which appears far to often on this forum. How I can come to the same (correct) conclusion as many of the experienced people on here with regards to that chart, considering my very limited exposure to the models, while somebody so accustomed to them can differ from them so much is strange. Really doesn't help with the learning process that so many on here, such as JH, attempt to aid. Charts to back up the statement would help in this regard

Trouble is that there is no 'right' answer with that chart, it's very much down to personal opinion. My opinion is that it's an unusual set up from there and I think its not possible to be confident about what comes next. Others may disagree however and his view is that its a nailed on westerly. Who knows, he may be right.

[The Post-modern Winter]

Trouble is that there is no 'right' answer with that chart, it's very much down to personal opinion. My opinion is that it's an unusual set up from there and I think its not possible to be confident about what comes next. Others may disagree however and his view is that its a nailed on westerly. Who knows, he may be right.

Exactly, there is no right answer. So don't make definitive statements with supporting them.

[chionomaniac]

A very strange request from you Chionomaniac considering the great work and time you have put

in to educate posters about the importance of the state of the stratosphere in winter time and the

undeniable link it has with the troposphere and different synoptics seen in the troposphere and

on the NWP model output.

 

I think all cold winter weather lovers should be very pleased with the GFS 12z run from a

stratosphere point of view.

It is more that this is the (tropospheric) model thread, cc, and I feel that we should concentrate on that in here and keep the strat influence in the strat thread. Granted, there will be some crossover - but I feel that there is currently becoming too much emphasis on FI strat charts in this thread. I think that we have reached a point where the influence of the strat on the trop is recognised by all and that I no longer need to labour that point as I felt I may have to have done previously. Therefore I am not saying that we should ignore the strat charts but perhaps modify the emphasis of them at this current time in this thread. In 10-15 days time there may be a lot more  correlation that is relevent to the trop output. It's a little bit too early yet though.

[lassie23]

A very strange request from you Chionomaniac considering the great work and time you have put

in to educate posters about the importance of the state of the stratosphere in winter time and the

undeniable link it has with the troposphere and different synoptics seen in the troposphere and

on the NWP model output.

 

I think all cold winter weather lovers should be very pleased with the GFS 12z run from a

stratospheric point of view.

Troposphere....enlighten me, I know nothing about this and how it affects our weather.