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

[winterof79]

A suggestion to all those who have read the "Death watch" shifts posts, who clearly need to concentrate on sleep more.

Click on the attached ay 0z scroll your mouse down through the Zs and relax. Watch the high eat up the lows as they try to attack from the Atlantic

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

Any low forming seemingly drawn under the block eventually

Edited January 11, 2017 by winterof79

[Methuselah]

Everything's look good, peeps; prolonged rain, sleet or snow for the sarf looking more likely for tomorrow, followed by three days' snow/sleet showers...

But, it's next week's potential easterly that's most interesting; it could be anything from a snowless borefest to a full-on Beast...If we could get substantial amounts of snowfall but without the excessive cold of Jan '87, I'll be happy. (And end up with a mental age of about 6!) And, hopefully, this morning's 06Z will be the first in a long line of model upgrades.

So, a question for those 'in the know': Do stronger easterlies actually produce more convection per se, or is it more a case of lighter ones not being able to penetrate far enough inland quick enough?

[Seasonality]

1 minute ago, winterof79 said:

A suggestion to all those who have read the "Death watch" shifts posts, who clearly need to concentrate on sleep more.

Click on the attached and relax. Watch the high eat up the lows as they try to attack from the Atlantic

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

Ha ha, was making this exact same point with a poster who thought the undercutting low would mean zero chance of retrogression and a sinking high. Here we go in gif form! Watch the vortex shift east and the lows get devoured and hoovered into Europe. Ending with HP to the north and LP to the south and the naughty Azoroslug squished and salted. Cheer up everyone!

[winterof79]

3 minutes ago, Ed Stone said:

Everything's look good, peeps; prolonged rain, sleet or snow for the sarf looking more likely for tomorrow, followed by three days' snow/sleet showers...

But, it's next week's potential easterly that's most interesting; it could be anything from a snowless borefest to a full-on Beast...If we could get substantial amounts of snowfall but without the excessive cold of Jan '87, I'll be happy. (And end up with a mental age of about 6!) And, hopefully, this morning's 06Z will be the first in a long line of model upgrades.

So, a question for those 'in the know': Do stronger easterlies actually produce more convection per se, or is it more a case of lighter ones not being able to penetrate far enough inland quick enough?

I would suggest the slower the feed the more time the temps have to be modified over the relatively warm  North Sea. Probably much more to it.

[winterof79]

1 minute ago, Seasonality said:

Ha ha, was making this exact same point with a poster who thought the undercutting low would mean zero chance of retrogression and a sinking high. Here we go in gif form! Watch the vortex shift east and the lows get devoured and hoovered into Europe. Ending with HP to the north and LP to the south and the naughty Azoroslug squished and salted. Cheer up everyone!

Doh ! Why didn't I just post the gif. Thanks for that though

[Tim Bland]

23 hours ago, Tim Bland said:

Re ECM / GFS debacle I have seen it many times before in 15 yrs of model watching.  What we are likely to see is a middle ground,  this to me looks like a mid lat block over us stretching to Scandi. This will mean a slack easterly for the south.  I expect the GFS to creep towards ECM over next few runs and the ECM to back track slightly until they meet in the middle.  It is very rare for one model to be totally correct and the other wrong.  Hope I am wrong though and ECM is 100% correct!

 

As stated yesterday the models are gradually adjusting to find a middle ground.  Worth remembering this for future as it almost always works out this way with no 1 model being correct.

Regardless of next week there is lots of snow opportunities in the next 4 days.  tomorrow could see 10cm on high ground i.e. Chilterns & Downs. Friday morning it is the time for Eastern areas to see a spell of snow. Sunday we see a front approaching from the west which could have snow on the leading edge.  Throughout the next 4 days anywhere could see snow showers more especially the North west.  my advice ; Enjoy the next 4 days and don't get carried away with the will it or wont it Easterly, which in my opinion will just be a slack flow across the south and only light flurries near the east coast.

[Summer Sun]

UKMO extended looks settled

[tight isobar]

Always better tohave cold air in place longer the better at land mass..then any convection is good..slacker the feed more coastal. .stronger the flow more penatrative precipitation! !!! But yes eastern /south eastern England. .can do well out of proposed set ups.

[Summer Sun]

The GFS ens isn't looking as cold for next week now we go from around -7 850's on the 14th to around 0 on the 16th

Whilst not mild it certainly won't be as cold next week if correct

 

Edited January 11, 2017 by Summer Sun

[Summer Sun]

 

[The Weather Dragon]

Morning all - as expected the raging easterly has now been tamed. We look likely to end up with a mid latitude block of sorts with a nondescript easterly/southeasterly component. Cold but not what most of us really desire. That said short term upgrades on the upcoming wintery snap mean that many may see a decent snowfall event with reasonable accumulations. 

Edited January 11, 2017 by Jonathan Evans

[Man With Beard]

1 hour ago, bluearmy said:

Was going to post about over analysing 8/10 day op output - even the ultra consistent ecm now illustrates that whilst it will be possible to pick the broad pattern, the accurate placement of surface features within 500 miles at 10 days (if they exist at all) is not feasible 

Btw, you all missed that little system day 10 coming down from Norway - doh!

Nice spot!

[bluearmy]

3 minutes ago, Man With Beard said:

Nice spot!

But the 'doh' should be noted in the context of the previous paragraph!

 

[john mac]

10 hours ago, nick sussex said:

In your own time GFS, for heavens sake get on with it! zzzzzzzzz

Unbelievable mate isn't it. I reckon it will be summer by the time the GFS catches up with the EUROS!!

[Guest]

Another short one as I have very little time right now. There is far too much gloom on here this morning and I remain extremely optimistic and this is definitely not a ramp. This week's northerly was widely expected to be brief but while it lasts it will be a pretty potent one with some snow in many parts. After that, none of the models bring in anything remotely mild for next week. The consensus is for slack or high pressure to move over us. This will be a period of cold or very cold surface conditions (especially where there is lying snow). One advantage of the "brevity" of the Arctic incursion is that the low heights over Scandinavia do not push the deep European cold block too far east. There will be a widespread area of stagnant surface cold over the UK and much of Europe - quite a rare occurrence in recent years.  There is then huge potential to pull in a flow from an easterly quarter. Now who said there wasn't any model agreement (yes, nearly all of us, including me). Let's look at an important period of cross model comparison. I have picked out the 0z T+144 charts (note: that the JMA has not updated yet, so their chart is yesterday's 12z T+168). Quite amazing similarities for D7 charts especially compared to recent weeks. Yes, there will be different evolutions, different pathes of getting there and a greater divergence beyond a week but come on guys this is a fantastic period of model watching with a huge amount of potential for coldies.

0z T+144 Comparision: 

                         UKMO                                                          ECM                                                    GFS                                                            GEM                                               JMA (12z T+168)                                        

       

                      NAVGEM

EDIT: A few excellent posts during the last hour. @johnholmes - your link to your own "will it snow imby" criteria, is a good reminder for all of us and is particularly useful for newbies. @Tamarait is great for the likes of you, me, John Holmes and a few more regular posters not to always have to manage others' expectations. @ anyone else - just enjoy the next few weeks and watch things unfold and never place too much hope or despair on a single model's output in one run!

Edited January 11, 2017 by Guest
Correct typos

[Weathizard]

The GEFS have no interest at all in a snowy easterly, a few show us under an easterly flow but that would be extremely cold and not much in the way of precipitation, can't look at the EC suite at the moment but if what isnreported is true looks like a big step away from anything noteworthy.

That being said, we are still in the game and it's better than zonal that's for sure!

[Ali1977]

19 minutes ago, Summer Sun said:

 

This seals the chance of a very cold next week from the east but I still think the ECM had the best handle on things as it's still looking pretty close to what it's said over the last few days, only a few hundred miles out.  The GFS was way off and moved towards the ECMs thoughts so those saying the GFS has won are way off, infact I think the ECM has outperformed the GFS so far this winter.  Imagine if the GFS starts swinging colder on this run, is it out of the question I wonder!!!

Edited January 11, 2017 by Ali1977

[tight isobar]

Far too early to dismiss easterly prospects! ! As models/previous easterly incurring have noted..it would be as ludicrous to dismiss' as much as to say its nailed. A few more bumps throughout output yet.

And im sure today we'll see the gfs vs ecm..being evaluated on whom is/was closer on the money! !!!

[AWD]

40 minutes ago, winterof79 said:

A suggestion to all those who have read the "Death watch" shifts posts, who clearly need to concentrate on sleep more.

Click on the attached ay 0z scroll your mouse down through the Zs and relax. Watch the high eat up the lows as they try to attack from the Atlantic

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

Any low forming seemingly drawn under the block eventually

As per this post, the outlook really isn't that bad.

The GFS has moved strides over the last week or so.  It has lost it's Atlantic zonal train and began showing a MLB'd scenario with little rainfall (ignoring deep FI).

The EC Op has brought the broad idea of heights to our E/NNE/NE/ENE down from T240 quite consistently.  Yes, some of it's deterministic output has shown a more substantial easterly but considering the timegrame involved, IMO, it's done very well.  If you've been scouring EC T144+ output for a snow shower over Ipswich then you've set yourself up for a front seat rollercoaster ride.

So the EC has been a tad ambitious on some deterministic modelling, but the posts in here describing the eps have always cautioned the EC Det to be on the optimistic route, with a slightly less amplified high likely.  

The 0z EC run still maintains below average surface temperatures for the majority of it's output for the south of the UK.

The GFS, well, the less said about that the better.  At least it is starting to toy with the blocked idea now.

The one slight concern I will admit too is the UKMO output.  I'm not convinced that would go onto producing any continental flow whatsoever for the UK, but as it only goes out so far, I'm not going to pretend I know too much about where we would end up in the UKMO 0z scenario.  I await further output regarding this model.

All in all, taking a blend of this mornings modelling we have;

Thursday - a rain - hill snow - wet snow all around event for southern England, snow showers for Scotland & Northern Ireland.  A cold but drier day for areas in between.

Friday - coastal rain/sleet with inland snow for eastern areas.  More snow showers for Scotland & Northern Ireland & the extreme west of Wales & SW moors, a cold (bitter windchill) day for all other areas.

The weekend - further wintry showers down the east coast and the north of Scotland.  Rainband moving in from the west, with possible leading edge wintriness.  Unsure as to it's eastward extent.

Mon/Tues - a slightly less cold couple of days with the colder upper air mixed out.  

Midweek onwards - uncertainty increases, but every chance of a cold continental flow for the south of the UK as colder, drier upper air filters back into the south from a bitter eastern Europe.  Less cold oooop north with more of an Atlantic influence.  Much drier away from the far NW.  Possible hoar frosts towards the south.

After that - who the fack knows.  I don't. 

All in all, personally speaking, I'm happy enough with that.  

Edited January 11, 2017 by AWD

[MKN]

Ecm finally toning the easterly down as i expected. The high was always most likely to sit over us given its the form horse in such situations. Have seen it happen far more than have seen the easterly materialise. The good thing is it should be dry cool with frosty nights would be nice if some areas can keep hold of any snow that falls between now and Saturday. 

[TSNWK]

24 minutes ago, Summer Sun said:

 

And yesterday it was all 51 members supporting a E'ly in my view too much credence is given to these tweets, which appear to flip flop like a fish out of water, several times a day - rather disingenuous to folk who spend tine and effort detailing their thoughts, offering charts etc.

[Light Without Heat]

Interesting tweet from local Beeb boy Hudson 

[Weather Boy]

7 minutes ago, Weathizard said:

The GEFS have no interest at all in a snowy easterly, a few show us under an easterly flow but that would be extremely cold and not much in the way of precipitation, can't look at the EC suite at the moment but if what isnreported is true looks like a big step away from anything noteworthy.

That being said, we are still in the game and it's better than zonal that's for sure!

It may not have been your intention, but this implies that the ECM modelled a snowy easterly, which it never did.  It modelled an easterly that would be very cold with snow a possibility down the line, but pressure was always quite high and although there was cause for debate about possible convective activity, it never showed a "snowy easterly".  For me, at least, this has never been on the cards in the foreseeable.

I agree with posters that say that it looks highly likely that ECM has won the day.  Obviously we don't know for sure until the weather happens, but it has dragged the GFS towards it kicking and screaming.  It would be churlish to complain that it has toned down its most extreme scenario, as modelled last night.  Models almost always do that.

[bobbydog]

1 hour ago, terrier said:

Well after a few days of excitement on the model output it seems like the gfs was right again. Think it has had some unjustified bashing by a few these last couple of days. But looking at the ukmo it's made a massive shift towards the gfs. And even though ecm not as bad certainly makes a move towards it aswell. Wouldn't be the first time this winter the gfs has trumped the euros.

Absolute and utter rubbish. The ECM has not budged for days. The UKMO has been on the same page. The GFS has now aligned to the euros. Whilst the most impressive charts have weakened a bit over 24 hours, we still have a scandi high and an easterly flow showing. If anything, the euros have "trumped" the GFS.

[Rocheydub]

1 minute ago, Weather Boy said:

It may not have been your intention, but this implies that the ECM modelled a snowy easterly, which it never did.  It modelled an easterly that would be very cold with snow a possibility down the line, but pressure was always quite high and although there was cause for debate about possible convective activity, it never showed a "snowy easterly".  For me, at least, this has never been on the cards in the foreseeable.

I agree with posters that say that it looks highly likely that ECM has won the day.  Obviously we don't know for sure until the weather happens, but it has dragged the GFS towards it kicking and screaming.  It would be churlish to complain that it has toned down its most extreme scenario, as modelled last night.  Models almost always do that.

Absolutely spot on analysis, bravo sir. You've read my mind, I was about to post that exactly!