Model Output Discussion 1st January 2014-06z onwards.

[EML Network]

Well the writing was on the wall the moment the models started shunting everything back East again. 

 

We've ended up pretty much where we started when the signal for cold was first picked up by the ECM and that is for the cold to stay East of the UK.

 

I've lost count of the number of times this has happened in the past, pretty much every Winter we get a faux Easterly in the the models, however,  the good thing is that more often than not a Faux Easterly is followed eventually by the real deal.

 

It's the normal way of things for us to need several bites at the cherry before we hit the jackpot, it's just sad that it's taken us 1/2 of the Winter to get the first failed bite.

 

It's also Worth bearing in mind that this only ever existed inside a computer model and has yet come to pass...it could flip back again but the odd's are not i favor of that happening. 

 

 I'm hopeful of something colder at the end of the month and into Feb. 

 

I have a sneaky feeling Feb is going to be colder than average nationwide 

[Essexfish]

Just a quick question; with the models moving away from an easterly scenario in the space of 24 hours is it not just as likely to move back in favour? 72hours ago an easterly was nothing but a pipe dream.

[nick sussex]

Looking at tonights T72hrs fax chart it doesn't look that bad! I'm still however dubious of how we get from that to the T96hrs UKMO raw output , is the low really going to make that much progress ne against the block, notwithstanding that the UKMO is isolated in its view of which low becomes the main player at T96hrs.

 

 

 

 

 

[carinthian]

Good Evening, just had a look at other models (12z ) some differences from our progs for this time next week. We still expect low pressure circulation over Southern Alps (1005mb ) with a strengthening Scandinavian high, even signs of pushing west. The Atlantic low to sink SE rather faster than UKMO and colder upper feeds than ECM indicate. Tomorrows shorter term forecasting system we think will provide a clearer indication if we remain on the right course.

 C

[smith25]

Good Evening, just had a look at other models (12z ) some differences from our progs for this time next week. We still expect low pressure circulation over Southern Alps (1005mb ) with a strengthening Scandinavian high, even signs of pushing west. The Atlantic low to sink SE rather faster than UKMO and colder upper feeds than ECM indicate. Tomorrows shorter term forecasting system we think will provide a clearer indication if we remain on the right course. C

sorry but could I have that in layman's terms please.

[cooling climate]

Are we saying FI is 120 with regards to the low in the Atlantic and how it progresses? 

 

The ECM and GEFS are pretty similar past 120 with the low though (sinking south)

I do not think anyone saw the ECM t120 chart coming and proves there may well be

surprises to come still.

[BLAST FROM THE PAST]

Indeed the GEM remains a very good run....again.  Also I'm sort of pleased with the ECM, its yes no yes no yes no.  Now experience has showed that if the pattern were to crumple the models would get onto it and remain onto it....they haven't and are producing unusual and sometimes odd scenarios.  That IMO is a positive sign.

BFTP

[bryan629]

part post 2766....from snowking this morning...hope you don't mind kriss.....Deterministic modelling is not as good as it was at say 0z yesterday but I think some people need to try and get their head around what NWP is trying to model here. Attempting to model the physics of two streams of jet energy travelling in two different directions running in to a blocking high is a ridiculously complex equation. There were various members yesterday trying to impart wisdom from years past to tell everyone that whilst face value model output was looking exceptionally good it would be some days yet before we would be able to determine the final outcome. We see models struggling enough to calculate fairly straightforward situations a week in advance, never mind something like this. When Ian F said yesterday that in terms of ensembles it was essentially a 50/50 split (with just a tad more on to the cooler side of the fence) he wasn't saying that for the sake of it, that really is what you get with situations like this, particularly against the background of how strong the jet stream has been.All I can say is it's a good job I am not a newer member attempting to decipher what on earth is going on because the conflicting messages this morning have been something else. What I would say to any newer members for now is this - wait until the weekend before drawing any major conclusions. The only certainty for now is that temperatures at the surface are going to drop in comparison to recent weeks.

 

 

I couldn't agree more.... have you all seen the varience on theme across the models at t+96

 

 

this looks very much like a Shannon entropy to my eyes ....and as ever more runs needed.

 

 

 

[weather eater]

I must be one of what seems to be too few members who is finding the evolution of this pattern fascinating and is enjoying it rather than finding it a mood rollercoaster   So much is changing from the pattern of the first half of this winter and for me, just as one illustration, the latest ECM output is underpinning that yet again, irrespective of face value outcomes. 

 

So much variance evident in the modelling as early as day 5 as illustrated by a few posters this evening already - and the balancing act between the heights to the NE and the attempted trough disruption to the west which the models are finding a complex equation to evaluate after the comparative ease of a tramline zonality conveyor belt so far this winter is a welcome sight to see imo after what we have been used to.

 

Much to anticipate and watch - as stated this morning. Enjoy, its only the weather 

Tamara I love you, my thinking exactly, how much more interesting is model viewing now compared to only a few days ago. I have to say what on earth were people expecting after yesterday, did they really think it was just a case of reeling the easterly in, perfect and formed and a straight forward count down from projection to reality, it never happens not ever. Perfect synoptics at 144hrs are useless and while there is a good chance that we may now see nothing but more downgrades from here on in, there is also a chance that it will all slot together as we get into the 72-96hr stage. And even if that does not happen, as the patterns evolve then new possibilities may open up, I think we can see that from how this ECM evolves, it wouldn’t take a great deal of change to develop into a big fat block running from Greenland to way out east. Plus it’s got me really interested in this community again, even if one or two of you drive me mad with your positive, negative, glasses up or tip of nose model viewing methods.

[winterof79]

sorry but could I have that in layman's terms please.

Carinthian is saying the850s shown on the ECM later would be lower than progged and the low on the ukmo further south east.Could be wrong.

[Froze were the Days]

To my untrained eye tonight's ECM looks very strange - low pressure that looks like it wants to sink south or south south east and then moves somewhat northwards again, even at 240z the potential is there to the north with hardly any Atlantic activity in fact a complete area of 'nothingness'. Am I the only one that is thinking the models are really struggling to cope with this evolving pattern?

Always 'ups and downs' when it comes to such a sustained pattern to get to something entirely the opposite.

A lot of watching to be done!

[DAVID SNOW]

Ensembles for central Europe suggest ops at the moment on the high side of the mean, significant spread after T120 so still could go either way for the north Italian low, GFS hasn't dropped it that's for sure. Massive uncertainty still.

 

PS, if you want a laugh, check out T240 pressure ens for Moscow, then you will see real uncertainty!!!

As you say much uncertainty: Did you look at the GFS pressure charts for Oslo!!!

[nick sussex]

part post 2766....from snowking this morning...hope you don't mind kriss.....

Deterministic modelling is not as good as it was at say 0z yesterday but I think some people need to try and get their head around what NWP is trying to model here. Attempting to model the physics of two streams of jet energy travelling in two different directions running in to a blocking high is a ridiculously complex equation. There were various members yesterday trying to impart wisdom from years past to tell everyone that whilst face value model output was looking exceptionally good it would be some days yet before we would be able to determine the final outcome. We see models struggling enough to calculate fairly straightforward situations a week in advance, never mind something like this. When Ian F said yesterday that in terms of ensembles it was essentially a 50/50 split (with just a tad more on to the cooler side of the fence) he wasn't saying that for the sake of it, that really is what you get with situations like this, particularly against the background of how strong the jet stream has been.

All I can say is it's a good job I am not a newer member attempting to decipher what on earth is going on because the conflicting messages this morning have been something else. What I would say to any newer members for now is this - wait until the weekend before drawing any major conclusions. The only certainty for now is that temperatures at the surface are going to drop in comparison to recent weeks.

 

 

I couldn't agree more.... have you all seen the varience on theme across the models at t+96

 

gemnh-12-96.png

gfsnh-12-96.png

UN96-12z.gif

ECH1-96.gif

 

this looks very much like a Shannon entropy to my eyes ....and as ever more runs needed.

Bryan thanks for that post, clearly highlighting that the UKMO is the odd one out compared to the ECM/GFS and GEM.

[nodrog]

A bit of a push and shove situation with High pressure setting up in the North East and later in the month far down South below the English Channel, Spain and surrounding area inc nr Atlantic.

 

This will stop the very cold conditions over Scandi coming West and stop any troughs or low pressure coming East, in fact pushing these Lows (pic) North towards Greenland leaving us in the middle with spells of rain and sunny periods with southerly winds for the next week or so... in turn biting heads off Exacta's white Arctic blast!

 

[Long haul to mild]

Tamara I love you, my thinking exactly, how much more interesting is model viewing now compared to only a few days ago. I have to say what on earth were people expecting after yesterday, did they really think it was just a case of reeling the easterly in, perfect and formed and a straight forward count down from projection to reality, it never happens not ever. Perfect synoptics at 144hrs are useless and while there is a good chance that we may now see nothing but more downgrades from here on in, there is also a chance that it will all slot together as we get into the 72-96hr stage. And even if that does not happen, as the patterns evolve then new possibilities may open up, I think we can see that from how this ECM evolves, it wouldn’t take a great deal of change to develop into a big fat block running from Greenland to way out east. Plus it’s got me really interested in this community again, even if one or two of you drive me mad with your positive, negative, glasses up or tip of nose model viewing methods.

I concur wholeheartedly. This is a fascinating set up; it looks as though the Atlantic is finally quietening down and we have a robust looking Scandinavian block setting up. It's only natural that the models are going to offer different solutions from run to run. I think that some people are obsessing too much on each run, and assuming that what is shown will actually end up happening.Yes, this is the model discussion thread and therefore what they show is why we are here, but I think a broader view is required in these setups.I for one am just glad I'm not logging in here every day to find yet another run showing Atlantic LP after LP bringing gales and rain to a country that has had quite enough of that recently!

[london-snow]

Carinthian is saying the850s shown on the ECM later would be lower than progged and the low on the ukmo further south east.Could be wrong.

Mr C our friend in the know from Austria. He has been pretty much spot on with his thoughts going forward add to that Mr Sussex is also doubting the output it certainly makes for interesting viewing for the rest of this evening and into tomorrow by no means is this possible easterly over.. Edited January 9, 2014 by london-snow

[ANYWEATHER]

Cant wait for the 00zs tomorrow .....back to the cold outlook

[Stuie]

Looking at tonights T72hrs fax chart it doesn't look that bad! I'm still however dubious of how we get from that to the T96hrs UKMO raw output , is the low really going to make that much progress ne against the block, notwithstanding that the UKMO is isolated in its view of which low becomes the main player at T96hrs.

 

fax72s.gif

I think you could say "choc o bloc"

Maybe we are looking to hard, maybe negatively at the model outputs. A couple of nudges West and surely battleground UK scenario. What if this all falls into place that easily?

 

There you go, positivity.

[IDO]

 Only one run but be prepared for a poor set of ECM ens upto T240 temp wise.

 

Change in temp of the Control compared to the 0z run at T228: 

 

The change with respect to the mean, again at T218: 

 

 

[Stuie]

 Only one run but be prepared for a poor set of ECM ens upto T240 temp wise.

 

Change in temp of the Control compared to the 0z run at T228: GetSlideMaps (16).png

 

The change with respect to the mean, again at T218: GetSlideMaps (15).png

It does look poor but surely T120 is the maximum length to look at currently.

[Captain Shortwave]

 Only one run but be prepared for a poor set of ECM ens upto T240 temp wise.

 

Change in temp of the Control compared to the 0z run at T228: GetSlideMaps (16).png

 

The change with respect to the mean, again at T218: GetSlideMaps (15).png

Actually it isn't that bad, the UK is -2C 850s or lower with a mean south easterly wind. Makes the 2m temperatures rather suspect in my opinion.The mean also shows the possibility of a marginal snow event days 5 and 6. 

The mean centers the low over Corsica in week 2, the UK caught between the Scandi high and the Atlantic high.

Edited January 9, 2014 by Captain shortwave

[Matty M]

ECMWF ensembles are relatively positive.

 

Lots of potential for a return to colder synoptics.

 

The Day 7 Ensemble mean could be a lot worse..

 

Edited January 9, 2014 by Matty M

[Gibby]

Hi everyone. Here is my evening report on the outputs from the NWP for today Thursday January 9th 2014 lifted from my website at http://www.norton-radstockweather.co.uk/Model-Analysis(2859336).htm

 

All models currently show the UK under gently rising pressure as a weak ridge crosses East over the UK overnight ahead of a weakening cold front moving steadily East across the UK tomorrow bringing an area of showery rain with it clearing from the West later in the day. saturday's charts from all models show a fine and dry day as a strong ridge of High pressure crosses East bringing colder air with a sharp frost and fog patches possible on Saturday Night. The respite from the rain then ends on Sunday as after a dry start a new Atlantic depression pushes wind and rain NE across the UK later in the day, heavy in places.

 

GFS then shows a very unsettled week next week as Low pressure slides South down the Western side of the UK through the period bringing rain and showers at times all week with the heaviest rain and showers reserved for Western and SW areas in temperatures close to normal. Northern and Eastern parts will be colder for a time with the risk of some of the precipitation falling as snow over the hills. Through the extended outlook the model shows the Azores High building NE across the UK to bring drier weather with temperatures close to normal across England and Wales before Atlantic Westerlies strengthen over the North with rain at times to end the run.

 

The GFS Ensembles tonight has evaporated the previously predicted cold spell to nothing as it now looks the changeable but largely unsettled spell will continue through the next two weeks though with less rainfall overall than lately.

 

UKMO tonight closes it's run next Wednesday with Low pressure with a deep Low pressure to the West of Ireland and showers or longer spells of rain over all areas through the day in temperatures close to average.

 

GEM tonight shows deeply unsettled weather with Low pressure areas sliding SE over the SW of the UK and bringing strong SE and occasionally cold east winds with rain copious in amounts at times and some snow on hills too at times as cold continental air flows West on the Northern flank of the Low pressure areas.

 

NAVGEM tonight is in the Atlantic camp as it brings deep Low pressure slowly East into the UK from the West through next week filling it gently as it comes in. the net result will be a lot of showers and longer spells of heavy rain at times with average temperatures and ongoing flooding issues almost anywhere.

 

ECM tonight remains poor news for those in the SW looking for flood relief as most of next week continues to show Low pressure close by with areas of rain and showers spiraling around various centres of Low pressure all week. It looks poor news too for cold fans away from NE Britain as too much Atlantic influence brings rain rather than snow in temperatures marginally colder than of late but at least far less windy. The run closes with the threat of colder conditions finally seeping West from Europe on slowly backing winds towards the East and with Low pressure still in close proximity to the South and SW some of the rain could begin to turn to snow over the hills.

 

The ECM 9 and 10 Day Mean Chart show a UK trough in response to High pressure likely to be near NE Europe in 10 days time with rain at times in winds from a Southerly aspect the most likely result.

 

http://www.wetterzentrale.de/pics/Reem2161.gif

http://www.wetterzentrale.de/pics/Reem2401.gif 

 

The Jet Stream shows the flow crossing the Atlantic next week and staying well South over Europe as a result of High pressure over Northern Europe. The problem is with an Azores High the trajectory of the flow over the Atlantic becomes problematic for the UK to tap into anything cold from the East.

 

In Summary tonight the spectre has fallen on anticipated cold weather next week as most output now shows unsettled and often wet conditions in temperatures close to average. Some particularly wet charts are shown which if verified would exasipate flooding issues with very little opportunity for anything profoundly dry for any length of time in any one place. However, despite the pattern between the models being generally similar the specifics are quite different in the period from midweek next week which indicates the models have not got a handle on longer term evolutions on tonight's outputs.

[Downpour]

Indeed the GEM remains a very good run....again.  Also I'm sort of pleased with the ECM, its yes no yes no yes no.  Now experience has showed that if the pattern were to crumple the models would get onto it and remain onto it....they haven't and are producing unusual and sometimes odd scenarios.  That IMO is a positive sign.BFTP

I think that's a very good point and to be fair it is exactly what Ian F chastised me about earlier. The utterly mad GFS Op run, which decided to create a limpet low that stayed in the mid Atlantic until the 12th of Never was the latest highlight of its many works of obscene fiction.

[shaky]

ECMWF ensembles are relatively positive.

Lots of potential for a return to colder synoptics.

The Day 7 Ensemble mean could be a lot worse..

very nice mean!!thought it would be a lot worse!!there could be changes for the better tomorrow!the mean charts look very good!!it actually carries on from this mornings and the -4 line is further south!!it actually looks like the operational is a mild outlier at the end!! Edited January 9, 2014 by shaky