Model output discussion - winter proper underway

[blizzard81]

2 minutes ago, damianslaw said:

Mmm its that christmas feel at the moment - christmas day now in the reliable, and yes we are we have been the seventh year in a row, a predominantly mild outlook for the run in to christmas - and very unnispriring fayre to be boost - pity we can't be where we were two weeks ago - its a cruel undertaking this year it feels..

Lackclustre is the word.

I am going to refrain from model watching for a few days - enjoy christmas and come back in the run in to new year - hopefully the models will show some wintry fayre. Hoping  2018 can deliver a cold snowy spell in the run in to christmas, seven years of mild muck is too much - merry christmas!

Like I have said many times before, Xmas time in the UK is hardly ever a snowy one. It may be chilly if  you are lucky. This goes for the classic cold winters as well. 

 

[damianslaw]

Agree - it always seems to go XXX up when it comes to christmas - more likely to see snow and cold in March and indeed april (an easter) than christmas - its the most unlikely time of year to sustain cold conditions - but this year it feels especially disappointing how the cold synpotics of recent weeks and the associated northerlies have been snatched away from us a week before christmas  - cruel indeed! all too early.

[blizzard81]

1 minute ago, damianslaw said:

Agree - it always seems to go XXX up when it comes to christmas - more likely to see snow and cold in March and indeed april (an easter) than christmas - its the most unlikely time of year to sustain cold conditions - but this year it feels especially disappointing how the cold synpotics of recent weeks and the associated northerlies have been snatched away from us a week before christmas  - cruel indeed! all too early.

Cruel indeed! However, I do feel January will deliver something to many of us. This is not winter 2010/2011. 

[damianslaw]

5 minutes ago, blizzard81 said:

Cruel indeed! However, I do feel January will deliver something to many of us. This is not winter 2010/2011. 

Yes - I think this winter offers more chance of colder interludes than any since 2012/2013 and we are not likely to see a 2010/2011 winter,  the jet seems quite weak, akin to 2008/2009 and 2012/2013 incidentally each brought a milder interlude second half of dec following on from cold starts to the winter-  its sods law the milder spells coincided with the run in to christmas.

Alas - taking a break now - back probably boxing day.

[Daniel*]

16 minutes ago, damianslaw said:

Mmm its that christmas feel at the moment - christmas day now in the reliable, and yes for the seventh year in a row, a predominantly mild outlook for the run in to christmas - and very uninspriring fayre to boost - pity we can't be where we were two weeks ago - its a cruel undertaking this year it feels..

Lackclustre is the word.

I am going to refrain from model watching for a few days - enjoy christmas and come back in the run in to new year - hopefully the models will show some wintry fayre. Hoping  2018 can deliver a cold snowy spell to greet the new year, seven years of mild muck is too much - merry christmas!

Well things are looking as good as they have done in a while, so I don’t quite understand your angle. In your part of the world the fells are going to get a nice white coat as 2017 comes to a wrap, so quite wintry for favoured areas. The end of 2017 still could offer something more substantial in terms of wintry weather even lowland, while not notable cold but the last 2-3 days model output has improved day by day let’s see what the new day brings. 

[blizzard81]

4 minutes ago, damianslaw said:

Yes - I think this winter offers more chance of colder interludes than any since 2012/2013 and we are not likely to see a 2010/2011 winter,  the jet seems quite weak, akin to 2008/2009 and 2012/2013 incidentally each brought a milder interlude second half of dec following on from cold starts to the winter-  its sods law the milder spells coincided with the run in to christmas.

Alas - taking a break now - back probably boxing day.

Yep, 2008/09 has rung in my head for quite a while now. Plus, my memories of cold first half of December's and back loaded winter's are very much in the forefront of my mind right now. 

[feb1991blizzard]

2 minutes ago, Daniel* said:

Well things are looking as good as they have done in a while, so I don’t quite understand your angle. In your part of the world the fells are going to get a nice white coat as 2017 comes to a wrap, so quite wintry for favoured areas. The end of 2017 still could offer something more substantial in terms of wintry weather even lowland, while not notable cold but the last 2-3 days model output has improved day by day let’s see what the new day brings. 

Are you sure?   Damianslaw doesn't get much snow even when we have a proper cold spell so what chance with a half baked nothingness one, I think a lot of people just assume everywhere in the North gets a tonking all the time and there are actually some really crap places for snow in the North.

[Daniel*]

1 minute ago, feb1991blizzard said:

Are you sure?   Damianslaw doesn't get much snow even when we have a proper cold spell so what chance with a half baked nothingness one, I think a lot of people just assume everywhere in the North gets a tonking all the time and there are actually some really crap places for snow in the North.

We only have to look roughly 5 days back when folk were on the cusp of putting out the white flag. Euro slug appeared to be in full control things have changed considerably. Cumbria can do quite well away with these set ups away from the coast inland with some good elevation. GEFS shows lows taking a more southerly track this is a good thing to see, we need further corrections for more than usual suspects to see some wintry weather.

Half baked? Nothing is in the flaming oven yet.  

D16 GEFS mean definitely looks wintry for Scotland. I’d be quite happy if I was up there! 

 

[A Frayed Knot]

Its coming ' i tell you not ' its coming ... I feel it and i smell it ' after the 27th of this Month its going to get COLD i tell yah i tell yah ' you never Listen though ' i feel it in me bones and i am  78 and still smoke a splifter .

Have a spliffy Crimbo to you all x

[Duane S.]

I think it is becoming increasingly evident that the ridging from the Pacific ridge over to our side, in and around the Greenland locale,is not going to be enough on its own. Beyond the possibilities of a temporally displaced PF jet to the south (and I don't see it heading that far south), we need reinforcements to stop the Atlantic from bulldozing in once those anomalous heights naturally begin to to wane. With no evidence of mid Atlantic amplification, perhaps our only hope is that we see the jet getting further south than currently forecast, creating a wedge. Long shot but this is not your standard winter setup and Arctic highs have a history of unpredictability 

i think the form horse, right now at least, is however a period of unsettled disturbed weather going into the New Year. There are hints of the creation of a Euro high, which could then be ripe to retrogress and feed WAA into Russia. Yes more mild but maybe transient and maybe worth the wait, with a robust Scandinavian high a possible outcome.

Just some thoughts before the 00Zs come out and take us down a completely different path altogether! 

[geordiekev]

30 minutes ago, A Frayed Knot said:

Its coming ' i tell you not ' its coming ... I feel it and i smell it ' after the 27th of this Month its going to get COLD i tell yah i tell yah ' you never Listen though ' i feel it in me bones and i am  78 and still smoke a splifter .

Have a spliffy Crimbo to you all x

Aah, that explains some of the early morning posts over the years.  I do hope you are right, and things are certainly moving in the right direction and that's good enough for me in the near term. Anything beyond requires medicinal comfort.

Merry Christmas indeedy ? 

[ArHu3]

@Bring Back1962-63

Never mind

Edited December 21, 2017 by ArHu3
Cant delete

[SMU]

The GFS strat forecasts this morning are as dire as they can be - approaching +VE levels like the nino December from ( 15?16?)...

not much HLB could survive that- all forecasts should be mild ATM

 

[knocker]

Today

Not much change from yesterday with the high pressure remaining to the south much of England and Wales and N. Ireland will be mild and murky with the odd spot of rain in the latter and one or two other places in the north. Much brighter in Scotland. Tomorrow a similar picture except light rain may well encroach western coastal areas.

By 12 Saturday the high cell is coming under pressure from the east bound energy and a shallow wave depression is just north of Scotland with the front trailing away to the south west and rain already affecting the west coast of Scotland. Further south a brisk westerly is in place but still dry and mild. Over the next 48 hours the front and rain move slowly south as far as N. Ireland and the north of England but to the west it is still under pressure from the eastbound energy and by 12 Xmas Day is orientated over Ireland and a wave has formed on it and popped north east to be over southern Scotland. This could well produce some snow in central and northern Scotland. All the while England and Wales remaining dry in the brisk, quite mild, westerly which gradually backs.south westerly.

This really heralds the start of a much more unsettled period as the front and rain traverse the the UK overnight, there could well be some more snow in Scotland and perhaps northern hills, before clearing the south east early Tuesday. But this is a very brief respite as the next low tracks quickly in from the NNW on a very strong low level jet and is 987mb over the Midlands by 1800 bringing a fair bit of rain the the south. Once more perhaps some snow on the northern edge of the front but best left to nearer the time.

The low quickly moves away to the east but meanwhile another intense depression in mid Atlantic has undergone explosive cyclogenesis courtesy of 160kt jet and is situated north west of Ireland with associated front just encroaching the south west by 06 on Wednesday. Fortunately the low is filling by this stage but it tracks into the Irish Sea during the day and this could bring severe gales the the SW and Wales and perhaps a fair amount of snow in Scotland

The low quickly moves east initiating a transient cool northerly flow over the UK but out in the Atlantic the 'bombing' scenario is being repeated, albeit the low taking a different track, and by Friday more fronts are approaching the south west.

The GEFS anomaly this morning is not adverse to this scenario.

 

Edited December 21, 2017 by knocker

[Dennis]

7 hours ago, Blizzards18 said:

But surely an Arctic high would help push the jet stream further south and at this time of year would open more doors than it would close. Beyond that is FI, so I wouldn't be pinning on anything but change

true

[SMU]

46 minutes ago, Steve Murr said:

The GFS strat forecasts this morning are as dire as they can be - approaching +VE levels like the nino December from ( 15?16?)...

not much HLB could survive that- all forecasts should be mild ATM

 

Just to add

wind ( storms ) / rain / warmth are sadly the watch words to the new year- 

[Dennis]

Just now, Steve Murr said:

Just to add

wind ( storms ) / rain / warmth are sadly the watch words to the new year- 

hi - why is this chart suddenly down with lines and we see this what you showed.....?

[Chesil View]

Just the normal Christmas and new year crud then after a glimmer or two of hope in the models and teleconnections.. 

It is a fact that is truer and true. No amplification or retrogression then no genuine sustained or longlasting cold or snow. (away from the high ground that always gets it).

For newbies another rule to take on board. nine out of ten of these 'promising' scenarios will fail to deliver widespread cold and snow.

 

 

Edited December 21, 2017 by Broadmayne blizzard

[West is Best]

Well aside from the potentially interesting cold meridional zonality around 25-27 December, this morning's GFS 0z ensembles show just how far on the mild extreme the operational was. I continue to have hope therefore.

 

[Severe Siberian icy blast]

54 minutes ago, Steve Murr said:

Just to add

wind ( storms ) / rain / warmth are sadly the watch words to the new year- 

So if your so certain of a mild and wet January, and now Glacier point also saying a similar theme yesterday, why was in only a week maybe 2 at the most that him and others were posting very good reasoned out posts all pointing to our north east in the new year, very confident forecasts explaining why it looks nearer enough a dead cert???

This happens every year and it seems peeps never learn. 

Signals and teleconnections seem to be as fickle as anything else imho. 

Can you or glacier point explain what's suddenly gone wrong on what seems to be a chatostrophic scale?

Cheers 

[West is Best]

1 hour ago, Steve Murr said:

The GFS strat forecasts this morning are as dire as they can be - approaching +VE levels like the nino December from ( 15?16?)...

not much HLB could survive that- all forecasts should be mild ATM

 

Not so sure I entirely agree with this. I'm not quite so tied to the upstream signals as you Steve, though I defer to your obvious forecasting professionalism compared to mine*. Not only does 25-27 offer some cold meridional incursion (with considerable snow potential up north showing on the 0z charts) but the ensembles still offer potential for changes. I'd say that beyond 27/12 is currently uncertain and I won't be surprised to see some dramatic changes ahead in the next few days.

 

*Which began at school when I made a barometer out of a milk bottle, stretched old balloon, a cork, a straw and a line on the wall   It was November 1978. The winter which followed was sensational.

[Severe Siberian icy blast]

On 13/12/2017 at 12:03, Glacier Point said:

06Z GEFS and op has just added to the model fog cerca 22nd onwards. As per previous thoughts, we're approaching a transitional phase, timed around the switch from December to January.

The low frequency tropical forcing signal has, and will continue to be centred around 140E - 160E in the Western Pacific. 

That's likely to maintain angular momentum in an elevated state relative to La Nina, so persistent signal for the GWO in phase 8 during the Christmas and into New Year period. The composites for this phase over the two separate months highlight the issues ahead of the modelling:

That's solid support for the building Alaskan ridge in the medium term modelling and, persistence of ridge to our west.

Therein the changing seasonal wavelengths bring about the change. Trough signal back over Europe and height rises to our NE and N.

The Alaskan ridge poses some questions: where does it go given the composites for January don't see it sticking around too long; does it migrate poleward and become absorbed into the Arctic circulation (as looks likely)? How then does the North American trough behave ? Composite for January looks good for the ridge developing in the extended modelling off the SE USA, so some westward movement of the trough over Canada looks reasonable. Longer term, a reboot of tropical convection across the Western Pacific and increasing angular momentum look to favour a phase 4 transition of the GWO into January:

Lots to be interested in and a non-numerical approach offering plenty of clues ahead.

For reference sake this is glaciers very good post from the 13th dec, what's changed so much since then? From what I can tell the GWO isn't reaching phase 8 like expected and this could be the biggest driver? 

Thanks 

[knocker]

Predictable the ecm differs with the gfs next week and not altogether a surprise doesn't subscribe to the 'bombing' scenarios although it also is windy and unsettled.

By 00 Tuesday the front is orientated down the western side of the mainland with a wave over the north Irish sea where the main concentration of rain lies. The wave develops and tracks NE overnight, along with the heavy rain. to be north of Scotland by 12 Tuesday whilst further south the front tracks east to bring sporadic rain to most areas.

The low continues to hover around northern Scotland, 962mb initiating westerly gales and wintry showers whilst another low has tracked quickly east on a strong low level jet to be around the Brest peninsula by 00 Weds bringing heavy rain to the south west. Twelve hours later it is in the Dover Straits having dragged the rain along the south coast in it's travels.

After that it's all downhill

[Frosty.]

33 minutes ago, West is Best said:

I continue to have hope therefore.

 

Me too although it seems some have already given up before we even reach January..pathetic!..anyway, I agree with you.

[That ECM]

26 minutes ago, Severe Siberian icy blast said:

So if your so certain of a mild and wet January, and now Glacier point also saying a similar theme yesterday, why was in only a week maybe 2 at the most that him and others were posting very good reasoned out posts all pointing to our north east in the new year, very confident forecasts explaining why it looks nearer enough a dead cert???

This happens every year and it seems peeps never learn. 

Signals and teleconnections seem to be as fickle as anything else imho. 

Can you or glacier point explain what's suddenly gone wrong on what seems to be a chatostrophic scale?

Cheers 

What they are attempting to do is very very difficult. They can only go on what is being modelled at the time. The met have a lot of difficulty in this area because imo the weather patterns are unpredictable In the mid to longer term. I would in no way discourage anyone continuing in this area of forecasting and I would in no way make someone justify why it went wrong. It has to be understood that this is embryonic in terms of forecasting and should be encouraged but viewed in such way.

 

if this way of forecasting causes disappointment etc stick to output at t72 down to t0.