Model Output Discussion 29th December - Into mid-Winter.

[Man With Beard]

The UKMO seems better than the GFS at T144 tonight - phase with low over E Europe and could swing south by T168/T192?

Did anyone notice the -8C uppers and heavy snow at T288 ... on a WESTERLY???!

I still don't think we're on track with this one. Still a lot of tiny variables at D4/D5/D6. Hopefully the ECM will provide some consistency.

[East_England_Stormchaser91]

I see everyone is virtually discounting everything now after just a few flipped runs. If they can flip as easy as they have done over the past day, what would be stopping a flip back to different Synoptics in just a few days? It must be hard enough for the models to cope with such unusual non default type patterns, I.e deep cold over the Western US and handling of lows over the Azores. 

For me it wouldn't take that much to tap into the repeated modelled easterly, should heights be able to push further north towards the pole. 

[There's a storm a coming]

1 minute ago, Seasonality said:

I can see how runs like this are frustrating for some. Continual reloading pulses of cold air into central, eastern and south eastern Europe.

It is.....but all we need is a " trigger" and it could come our way

tasac

[gottolovethisweather]

37 minutes ago, nick sussex said:

Very frustrating output so far this evening. In typical model fashion the UKMO which was the one previous output no one wanted to verify is now better for cold than the GFS. And we get the cold closer to the east earlier but still not close enough.

 

 

1

The thing is Nick; things ARE going to plan up to D6 or thereabouts, but the -18 850s aren't looking likely to verify at D10 or whichever range they were tempting us which is NO SURPRISE to me. Sorry if I offend, not digging at you but I'm digging at those who got caught up in the hype. This is not to say that cold to very cold air won't reappear in the outputs, but when such conditions are within D5 range I'll join in the celebration, but only then will I do so.

Happy New Year one and all. 

Edited December 31, 2016 by gottolovethisweather

[LRD]

10 minutes ago, nick sussex said:

Very frustrating output so far this evening. In typical model fashion the UKMO which was the one previous output no one wanted to verify is now better for cold than the GFS. And we get the cold closer to the east earlier but still not close enough.

Even though it's been a bad day for those actually wanting some winter weather in winter (shock, horror) the fact that UKMO is showing something at 144 means there shouldn't be a complete write off of the cold. Have to say, though, that the direction of movement today is concerning. Once a cold spell is dropped in the model suites it rarely comes back. Jan 2013 being one example where it did (and guess who spotted that better than ECM and GFS and every other model - yes, the mighty UKMO!)

[karlos1983]

Short set are out, probably wouldn't even bother looking at the full set if it's certainty your looking for 

Unless you like spaghetti that is 

Edited December 31, 2016 by karlos1983

[There's a storm a coming]

5 minutes ago, There's a storm a coming said:

It is.....but all we need is a " trigger" and it could come our way

tasac

If the GFS has seen a new trend and the Atlantic comes back into play....you never know once it hits the block to our east it could split the jet stream and a low pressure could slip underneath...and that could be the trigger!

tasac

[nick sussex]

Looking at the UKMO that low to the north at T144hrs is more likely to drop closer to the east and the upstream pattern is more amplified. The problem remains the mess the models have made so far of those Atlantic lows and how and where they phase with low heights near Greenland.

The GFS is much faster upstream which we don't want to see. The issue with the UKMO is that when it comes up with a better solution for cold at T144hrs this normally hits the buffers whilst its less interesting output seems to verify!

We await the ECM with a good deal of trepidation!

[SMU]

25 minutes ago, Seasonality said:

I can see how runs like this are frustrating for some. Continual reloading pulses of cold air into central, eastern and south eastern Europe.

Indeed -

if you want snow go to turkey-

S

[There's a storm a coming]

4 minutes ago, karlos1983 said:

Short set are out, probably wouldn't even bother looking at the full set if it's certainty your looking for 

Completely agree lets see what is forecast to happen in next 6 days before looking further ahead especially in these " uncertain times"

tasac

[Dancerwithwings]

11 minutes ago, karlos1983 said:

Short set are out, probably wouldn't even bother looking at the full set if it's certainty your looking for 

Wouldn't bother the spread is   http://www.wetterzentrale.de/de/show_diagrams.aspx?model=gfs&var=2&lat=52.4814&lon=-1.8998&lid=ENS&country=de&zip=&bw=False

 

 

Edited December 31, 2016 by Dancerwithwings

[LRD]

4 minutes ago, Dancerwithwings said:

Wouldn't bother the spread is   www.wetterzentrale.de/maps/GFSENS12_52_-2_201.png

 

 

In the space of 24 hours (or even less) the 850 temps have gone from a mean sitting at just below the -5 mark to now being just above the 0 mark -  for the period around 6-8 January. Sheesh, disappointing isn't the word. Never flips the other way in winter does it? 

Edited December 31, 2016 by LRD

[mountain shadow]

23 minutes ago, East_England_Stormchaser91 said:

I see everyone is virtually discounting everything now after just a few flipped runs. If they can flip as easy as they have done over the past day, what would be stopping a flip back to different Synoptics in just a few days? 

Because in our islands its a one way street.

I cannot recall the models ever flipping back to cold once they have moved away from it.

Dearly need to see the ECM build some Scandi heights in FI in an hour.

[Stuie]

Looking at the JS you could certainly argue heights want to build near Scandi.

[LRD]

27 minutes ago, East_England_Stormchaser91 said:

I see everyone is virtually discounting everything now after just a few flipped runs. If they can flip as easy as they have done over the past day, what would be stopping a flip back to different Synoptics in just a few days? It must be hard enough for the models to cope with such unusual non default type patterns, I.e deep cold over the Western US and handling of lows over the Azores. 

For me it wouldn't take that much to tap into the repeated modelled easterly, should heights be able to push further north towards the pole. 

Because, unfortunately, that hardly ever happens. I can only think of one example (in winter) and I've mentioned that example too many times on here already! Once the models revert back to climatology it stays on that road. My perception is that happens more so in winter than summer but I could be wrong 

[Methuselah]

2 minutes ago, LRD said:

Because, unfortunately, that hardly ever happens. I can only think of one example (in winter) and I've mentioned that example too many times on here already! Once the models revert back to climatology it stays on that road. My perception is that happens more so in winter than summer but I could be wrong 

But, how do they do that, 'revert back to climatology', LRD? What if their 'starting position' was outwith climatology? What would they do then? And wasn't THAT GFS's T+336 'solution' stretching climatology to its very limit? 

[AWD]

15 minutes ago, LRD said:

In the space of 24 hours (or even less) the 850 temps have gone from a mean sitting at just below the -5 mark to now being just above the 0 mark -  for the period around 6-8 January. Sheesh, disappointing isn't the word. Never flips the other way in winter does it? 

Edited December 31, 2016 by AWD

[Daniel*]

It may be a far fetched idea - but is the ridge destined to sink over the UK? Could it be pulled westwards, if we see see more amplitude of the ridge off the eastern seaboard/ southern tip of Greenland. A definite upgrade compared to 06z for sure, better orientated and more sharp to encourage a link up. Also the more positively titled the troughing in the Atlantic is as evident in 12z, the greater the likelihood of HP in the vicinity of the UK wanting to stretch its arms over to its distant American friend, correct me if I'm wrong? I'd still not rule out an northerly, a few ENS members do although a clear minority. It is far from gameover IMO even at relatively short timeframe it may look bleak. I'd still say the small details (which some have seen to look over) ultimately have huge stake in what happens are still uncertain, and so there is hope at least. I might be scraping the barrel but it's what I see I could be wrong.  

GFS 06z /12z at T+102

 

[LRD]

1 minute ago, AWD said:

According to the quoted graph, the ens mean sits around -2/-3 for the period you state.  Never does it breach the 0c mark.

You're looking at the red 1981-2010 mean, surely? I'm looking at the thick black line. That's the ensemble mean

[phil nw.]

I really think with the difficulty of modeling a split Atlantic jet it is even more advisable to view the operational charts beyond days 4/5 with an open mind.

I have been comparing the last 3 12z GFS and UKMO Op.runs for the same day-Jan 4th to look at trends in the shorter term.I concluded that if anything more energy has gone into the southern arm of the jet.Below the Jet pattern for that day with the oldest chart on the left

 

A look at the UKMO pattern for the same day,again the oldest chart on the left

see on the GFS jet pattern the better split going south off NA and on the UKMO charts the greater ridging of our high and the Scandi.trough closer by.

Just something to think about-if after the first few days GFS has modeled the split jet with too much emphasis on the northern jet then later on the Atlantic ridging will be flatter.

Looking at the ens still looking cold-2m temps- from next weekend although quite dry,again the easterly was never favoured in the ensembles so if it appears later on in the month then that's a bonus.

 

 

Edited December 31, 2016 by phil nw.
removed incorrect image

[LRD]

4 minutes ago, Ed Stone said:

But, how do they do that, 'revert back to climatology', LRD? What if their 'starting position' was outwith climatology? What would they do then? And wasn't THAT GFS's T+336 'solution' stretching climatology to its very limit? 

Gawd knows. But that's what seems to happen! An out-of-the-ordinary spell is predicted, then is usually not retrieved once the idea is dropped

[phil nw.]

A couple of off topic posts have been removed.There is a thread for Historical weather/charts.

https://www.netweather.tv/forum/forum/40-historic-weather/

Just discuss current outputs/charts in here please.

Thank you.

[ArHu3]

ECMWF big changes at 96h out, seems to be following UKMO, hopefully with a better outcome but it will be very different for sure (i have a bad feeling about this though)

Edited December 31, 2016 by ArHu3

[Singularity]

For now at least, I'm willing to entertain an idea that the incredibly favourable handling of the Azores low by GFS until late yesterday was leading to evolutions that could not be taken down by model bias toward too much energy in the northern arm of the jet where there's a split taking place. With the loss of such favourable Azores low behaviour we've found ourselves looking at what we usually see from GFS when a Scandi High is possible in the 6-12 day range; excessive flattening of ridges by the N jet arm.

In which case its now a question of whether adjustments such as made by the 12z GFS and UKMO this evening can go far enough to turn the longer term output back around in terms of the typical flow of air across the U.K.

 

Bear in mind that celebratory booze has loosened my sense of what seems reasonable, but I'm sure I've seen such a sequence of events before, and not just in Jan 2013 when it may well have occurred.

We can but hold out hope for 2017 to treat us more kindly than 2016...

[booferking]

3 minutes ago, ArHu3 said:

ECMWF big changes at 96h out, seems to be following UKMO, hopefully with a better outcome but it will be very different for sure

ECM following from last nights run..