you be pushed to beat 31/10/2008 in recent times Q snowed in London quite heavy very cold in the n/e wind

http://www.wetterzentrale.de/topkarten/fsreaeur.html

2012 was superior even though it didn't snow in London, the arctic air-mass got much further south. However neither of these cases count because the airmass was mA in both cases. 

These pictures (2012 left, 2008 right) show the air masses before the source was cutoff and warming started to take place, in both cases the coldest air did not reach the south until a few days later but 2012 was marginally colder. Having said that, 2008 is far more direct, as you can see in the above, if a trough hadn't formed (which actually gave London the snow) then the 2008 event would probably have been even colder than the 2012 one. But anyway as you see here both are mA events not cA/cP.

My turn now. I'm not sure I am allowed to show images from weatheronline but if it is a no no then please let me know and I'll delete this post (or the mods can do it for me).

Just that I thought this has some interest, where it is unusual to see good agreement between the two big boys at the 240 hours range, especially at this time of the year. It is a million miles away in forecasting terms and it'll probably look different tomorrow, but for now, it is having the effect of soothing my furrowed forehead . . .

GFS . . .

http://expert-images.weatheronline.co.uk/daten/proficharts/en/2014/10/07/basis12/euro/pslv/14101712_0712.gif

And ECM . . .

http://expert-images.weatheronline.co.uk/daten/proficharts/en/ecmwf/2014/10/07/basis12/euro/pslv/14101712_0712.gif



EDIT: Decided to show them as links after all.

Posting Weatheronline images without permission results in an ASBO, Ian 

  Just re-amended my last post.

I'm confused are we allowed to use weatheronline?

I only use them in an emergency as their graphics are inferior to most other sites, but the advanced parameters are really useful. Ah well I guess I can always use open grads for advanced stuff :S

The models have made slight adjustments this evening, now coming together on the theme of low pressure gradually fading away through this weekend into next week, leaving us with light winds and some slow moving showers, followed by a large trough in the Atlantic taking over proceedings while stalled to our west.

This idea of the trough being stalled is a recent development after previous runs favoured a system tracking NE without much hesitation.

This from ECM shows a textbook advection of warm air (Warm Air Advection) northward up the western flank of a high pressure cell that is developing into a strong blocking feature, largely down to support from the WAA.

GFS comes uncannily close to this on it's 12z op run, as Ian spotted earlier.

This trend could setup a long-fetch southerly with some unusually warm days on offer, which ECM and GFS both manage to some extent, or it could, if the blocking high aligned in the right way, pull across chilly air from a point of origin somewhere NE of the UK.

For that to deliver much more than dreary skies filled with low cloud and a miserable damp chill to our shores, the easterly flow would have to be a strong one and the air mass unusually cold, in order to avoid too much moderation by the North Sea surface temperatures.

HERE IS MY LATEST ANALYSIS FROM THE OUTPUTS OF THE WEATHER COMPUTER PREDICTION MODELS FOR TWO WEEKS FROM 8AM TODAY WEDNESDAY OCTOBER 8TH 2014.

NEXT UPDATE THURSDAY OCTOBER 9TH 08:00

THE CURRENT GENERAL SITUATION. An unstable West or SW flow covers the UK with a deep Low approaching Western Britain tomorrow.

MODELS-2 WEEK HEADLINE  Low pressure easing away North and West with pressure rising later over or to the East and SE of the UK.

THE JET STREAM ENSEMBLE FORECAST The Jet Stream is likely to remain positioned well South of the UK for the next 4-5 days while weakening steadily. It then buckles South across the Atlantic and returns in a North or NE flow up the Western side of the UK before settling back to a generally Easterly flow across the heart of the UK by the end of week 2.

GFS The GFS operational his morning shows the current deep Low to the West of Ireland moving slowly North and NE filling slowly over the coming days but remaining influential well into the weekend with it's showers and rain at times for all. Pressure continues to gently rise early next week in response to deep Atlantic Low pressure throwing a ridge across the UK and Northern Europe drying things up for many. Later in the run this High declines SE and a SW and then Westerly flow with Atlantic Low pressure running across Northern Britain is shown to return rain and wind at times to all parts later in generally near to average temperatures.

THE GFS ENSEMBLES. The GFS Ensembles differ only in small scale synoptics to that of the operational with the resultant conditions at the surface remaining very similar to that of the operational in that after a showery remainder of this week and weekend a brighter and in places warmer period develops as High pressure builds over and then to the SE before a return to changeable weather under a predominantly Westerly flow develops later in week 2.

UKMO UKMO this morning shows pressure becoming slack across the UK at the weekend and into the start of next week though with pressure gently rising. Some slow moving coastal type showers are likely but with light winds and some clear spells at night some mist and fog patches could become an issue night and morning.

THE FAX CHARTS  The Fax Charts show Low pressure to the West and SW with a complex array of troughs gradually transferring NE over the coming 4-5 days with the main centre lying close to the far North at the weekend as a much weaker feature as pressure rises slowly from the South and pressure becomes slack across the UK.

GEM The GEM operational today is broadly similar in the short term before it too develops a deep Atlantic low at the start of next week which sends up a strong ridge to the SE and brings warm SW winds and rain to the North and West before a large High just to the SE extends a ridge through all areas later bringing some unusually warm and bright weather across the South of the UK in particular from Southern Europe in a week to 10 days time.

NAVGEM NAVGEM also rises pressure to the SE next week though it is a slow progress. Nevertheless, by the middle of next week all areas become bathed in mild SW winds with any rain becoming restricted to the far North and West with some pleasant October weather developing across the South and East. 

ECM The ECM operational shows a more integrated push towards the UK of deep Atlantic Low pressure next week with a deep centre lying not far to the West of Ireland by the end of next week. This pushes the axis of the ridge of High pressure further East and allows a more coherent push of unstable but mild SW winds across all areas with rain at times becoming more extensive too by the end of the run.

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The trend towards at least a period of drier, warmer and brighter weather is shown by most models next week but there is some disagreement as to what extent and duration this might take.

MY THOUGHTS  Having seen GFS lead the way yesterday on a new theme of High pressure based weather yesterday morning and see this extended to later day runs too from many models it has decided to be less dramatic in the form this might take on this morning's output as the Atlantic proves a stronger beast, pushing the developed High to the East and SE next week while eroding it with SW winds and troughs of Low pressure. This theme is also shared by ECM which to be fair showed a similar evolution to this morning's run yesterday morning. It's left to GEM to fly the flag on some unusually warm weather extending North on the Western flank of the European High next week which would give some very pleasant weather in the SE late next week if it evolved as shown. So which is right? I think the carrot will continue to be dangled in upcoming runs on at least the possibility of some unseasonably warm weather towards the SE next week as the large Atlantic Low pressure sets up and brings the warm Southerly flow North. It's then left for the models to pin down the detail on how much the active Low to the West makes inroads into the UK with it's attendant wind and rain and how much of a fight the High to the SE puts up. So the only way to describe things for next week currently is to say that it will definitely become milder than currently for all and possibly warm in the SE. There will be the chance of rain at times too and this will mostly be focused on the North and West in the short term with the caveat that this 'may' spread to other areas too late in the forecast period. It will be interesting to see how the models play around with this deep Atlantic Low and European High over the coming days output with the UK as usual in the battleground between the two.

Cracking Forecast Martin

ECM develops a warm plume from North Africa for a time!

http://www.wetterzentrale.de/pics/Recm2402.gif

I wouldn't rule out some thunder from that.

amazing ecm output the mean likes it as well

http://www.meteociel.fr/modeles/ecmwf.php?ech=240&mode=1&map=1&type=1&archive=0

http://www.meteociel.fr/modeles/ecmwf.php?ech=240&mode=0&map=3&type=1&archive=0

A lot of cold air pooling around the back over western Russia as well...

Excellent, might allow for some decent snow cover to extend much more quickly westwards this year with that sort of chart - late October warmth is fine as it might be beneficial in the long run as it helps extend snow cover further east and north.

Interesting ECM tonight, should it verify. Potentially a lot of heavy thundery rain at T+120hrs in association with the nearby plume and relatively steep thermal gradients aloft.

One to watch 

Bloody hell Duane, I wouldn't rule out some thunder, plus torrential monsoon rain, inky black clouds, and more lightning flickers than a dodgy Ford Cortina MKIII headlamp bulb from a clear blue sky where you live! 

This is a very messy situation for the models to resolve, but they do seem to have come into agreement on the trough in the middle of the North Atlantic being absorbed by a rapidly developing system that is positioned in the far western North Atlantic in the above image - visible as a sharp trough in the 1015mb isobar.

In the above we can see how the low undergoes 'bombogenesis' (explosive deepening), with an impressive pressure drop of 40mb in 24 hours. Over the following 3 days it slowly winds down, and this is when a ridge looks to build up through Europe, potentially bringing some quite warm air up from well S or SSW of the UK.

ECM has the jet riding over the top of this ridge, holding it to our south, and to a great enough extent to keep more of a westerly flow across the northern half of the UK, limiting the advance of the warm plume of air northward.

For a time, GFS goes very much the other way, with the main jet blocked off and the ridge building up to our NE days 7-9. The run then suddenly blasts the block away at the transition to lower-res (192 hours), which makes it seem a little dodgy - the block would probably put up more of a fight if it was in the position GFS has it on day 8.

A blend of GFS and ECM would probably bring us more of a Euro-ridge but centered close to the UK. It would actually be the warmest version of events that appears within reach.

In all manners of respect amen.

Could it be that UK and Europe Climate Variability and handshakes the Times USA hands over to us maybe that and the Positive to Negative NAO and the Strato Polar Vortex being stretched out in December and March give us as has given since 2000 or at least the 2003-2014 decade scale of UK Europe Weather Climate Variabillity, and reduced Arctic Sea Ice in the Bering and Kara Seas help transfer more unstable Low Pressure in Arctic too.

And Regular Stratospheric Warming or Cold Polar Vortex waves made thanks to that and the High Pressure North Mid Lattitudes and Volatile Weather Systems of High and Low Pressure more variable in Greenland and Arctic Plus Svalbard etc are looking more favoured- spotted the trend in the period of 1899-2014.

A good Climate Change and Global Warming and Positive to Negative NAO, Seasonal and Monthly UK Weather Changes are at least continuing to entertain us I am happy with this news.

Do not take this with a huge pinch of salt anyday.

Well done, this one of my favourite story of the life as is for most to stay for like for us always, or some winters at least- much awaited London Winter Snowfall(s).

😀💭

HERE IS MY LATEST TEXT ANALYSIS FROM THE OUTPUTS OF THE WEATHER COMPUTER PREDICTION MODELS FOR TWO WEEKS FROM 8AM TODAY THURSDAY OCTOBER 9TH 2014.

NEXT UPDATE FRIDAY OCTOBER 10TH 08:00

THE CURRENT GENERAL SITUATION. A showery SW flow covers the UK as Low pressure fills and drifts North across Northern Britain.

MODELS-2 WEEK HEADLINE  Changeable weather with rain at times and strong winds too later but with some dry and bright weather for some next week especially in the East.

THE JET STREAM ENSEMBLE FORECAST The Jet Stream in this morning's GFS Ensemble run show the flow maintained close to Southern Britain for the next three to four days. It then weakens and splits with the main arm remaining close to the South of the UK with a weak northern arm to the North briefly weakening. Later in the run the pattern simplifies to a main West to East flow across Southern Britain.

GFS The GFS operational today shows the current UK based low pressure filling slowly and drifting North. It now looks like another Low moves NE towards Southern Britain at the weekend with more rain at times and it will become rather cool in the North. Then as this moves away pressure recovers and a couple of milder and brighter days are shown with mist and fog at night before the Atlantic is shown to ratchet up a few gears again with deep Low pressure crossing to the North and bringing rain and gales to all areas before colder and showery weather develops later on a marked cold North wind with some snow showers on Scottish mountains and frosts widespread at night towards the end of the run.

THE GFS ENSEMBLES. The GFS Ensembles look distinctly unsettled this morning following the operational up until the early part of next week. It then brings a deep Atlantic Low slowly in towards the UK with another batch of wind, rain and showers not dissimilar to the setup we have currently. This then becomes reinforced by further Low pressure from the West at the end of the run and with colder air entrained around a major Low to the North by the end of the run gales and heavy showers would be the order of the day for all with temperatures somewhat below average by then.

UKMO UKMO this morning shows pressure only very slowly rising at the weekend and start to next week with a trough remaining close to Southern Britain in particular maintaining the threat of some rain at times well into next week. Northern parts look like becoming rather direr if rather chilly by night with some mist and fog also a risk at night for many as winds will become generally light Easterly.

THE FAX CHARTS  The general thrust of the Fax Charts this morning focuses on a slow and gentle rise of pressure and a slackening of winds across the UK over the weekend and start to next week. There will be a lot of dry weather around but a lot of cloud at times too along with some night time fogs to clear. Some rain is also possible mostly in a showery form and more towards the South by Tuesday.

GEM The GEM operational today also shows Low pressure moving up perilously close to SE Britain early next week with some rain for many Southern districts. At the same time pressure builds to the North and NE and once the Low has passed a ridge builds strongly down across the UK with dry conditions with mist and fog at night and some warm days in the SE. The strengthening South-easterly winds on it's Western flank will bring cloud and some rain towards the far SW later.

NAVGEM NAVGEM also brings a new Low pressure up from the South towards Southern England early next week bringing more wind and rain here. it is shown to stay somewhat more settled in the North as pressure builds somewhat and this better weather then extends South to all areas towards the end of the run as Low pressure is held well to the west and a slack high pressure develops close to the East. 

ECM The ECM operational today brings new Low pressure up towards Southern Britain early next week with several more days of wind, rain and showers while the North stays at least somewhat drier with higher pressure to the North. Later next week the model brings Atlantic Low pressure into play and with pressure rising over the near Continent the weather warms up considerably under SW winds. However, fronts will be pushing slowly in from the West with some heavy rain and strong winds where the warm air meets the polar frontal zone somewhere across the UK.

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The trend has shifted away from a UK wide improvement towards a more modified version probably lasting only a few days and more towards the East.

MY THOUGHTS  A very complex synoptic pattern is shown to develop across the UK in the coming weeks as the desire for High pressure to rise from the SE and deliver some mild and pleasant weather is confronted by rather less desire for pressure to fall to the North of the UK next week. The result is a standoff involving a delay in improvements by slack pressure gradients across the UK and a new Low moving up from the South to affect principally Southern areas early next week with a renewed batch of rain and showers. Once this has passed there is a window of opportunity for high pressure to the SE to link with the ridge to the North and with the UK likely to lie on the Western flank of this a warming Southerly or SW flow is likely to develop from the middle of next week. After this the long term models remain mixed but it all hinges on how much progress and what angle of attack a deep Low pressure in the Atlantic has in making inroads into the UK later. Most of the longer term output does show it making at least some progress and setting up another windy and wet spell at the end of the run and if the door fully opens as GFS shows today then some very wet and windy weather is likely with colder air entrained too. It's all very complex this morning and will not be resolved until we see how the spanner in the works Low pressure early next week behaves with it's engagement of other pressure systems around the UK. So I think we can summarise by saying changeable conditions are likely over the next two weeks with rain and wind at times for all areas but with some drier and brighter periods too when it might feel quite mild.

In a nutshell... ECM appears a bit nuts:

With a bit of sun in the SE we could see a 25*C if that verified 

It comes about as a result of the trough digging south in the mid-Atlantic. Could it really be that simple? Probably not 

GFS doesn't feature the digging south at all on the 00z run with a near-dartboard low pushing steadily across the UK instead. Bah.

GEM, on the other hand, goes for a variation on the ECM run. This sees the HP build a fair bit further north but still position and align itself in a way which draws a huge plume of warm air northward - so much so that the 8*C 850hPa isotherm makes it all the way up to Iceland:

http://modeles.meteociel.fr/modeles/gem/runs/2014100900/gem-1-240.png?00

Is GFS being way too progressive in breaking down the blocking to the SE, E and/or NE?

The 18z GFS op run had more of an undercut going on but even then it refused to stop shoving the Atlantic eastward.

My conclusion? More runs needed, but the ECM/GEM theme seeming to have the upper hand as things stand this morning.

Always true but 10 days away... Be amazed if its anything like that on the day.

I knew you wouldn't turn down a freaky light show.

As Martin said earlier it is a very complex situation look at the change at t144 to t120 on ecm today

http://www.meteociel.fr/modeles/ecmwf.php?ech=144&mode=1&map=1&type=0&archive=1&mois=10&heure=0&jour=8&annee=2014

and now it says

http://www.meteociel.fr/modeles/ecmwf.php?ech=120&mode=1&map=1&type=0&archive=1&mois=10&heure=0&jour=9&annee=201

The different engagement with the jet stream makes all the difference also shown by the gfs control digging the jet a bit further south aided by slipping energy running from n/e to s/e re forces the block

0zgfs control also likes that idea

http:/http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=120&mode=3&carte=1

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=120&mode=3&carte=1

and before it goes

at 168

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=168&mode=0&carte=1

look at that disruption now

gm has been hinting of this idea on and off for a while,

look like a old fashioned eighties style winter battle ground setup

Hi all,

Here's today's video update:

Warming up next week but will it settle?

http://www.gavsweathervids.com

Pretty complex situation Re. next week.

Cheers Gav