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Some useful tropospheric developments upcoming which are likely to have stratospheric impacts towards the end of November and more particularly into December. A strong convectively coupled tropical wave is being forecast to develop in the Indian Ocean in the next week and migrate eastwards during week 2 (MJO phase 2-3-4-5 transition). We are likely to see jet extension and subsequent retraction of the Asian and Pacific Jets leading to a increase in tendency in relative angular momentum and the GWO spiking phases 4 and 5. Mountain torque territiory for the Himalayas. At the same time, long wave pattern over eastern Europe maintains a favourable Wave 2 projection. This is likely to be enhanced over time as the amplification resulting from retraction of the Pacific Jet works its way downstream. Both tropical wave and resultant wave 2 look very similar to 1986 evolution. The AO looks to be tanking +ve in the week 2 timeframe, ideal for wave activity flux (again similarities with Nov 1986 there). So bottom line is ingredients for stratospheric vortex being significantly weakened during latter part of December.

I spy with my little eye . Some GEFS members going pretty cold towards the end , touching -10 850s . It's all from the north too as per METO long range forecast . I know it's clutching at straws but it's better than not clutching at all

Certainly plenty of evidence to suggest the atmosphere may be conducive toward mid/high lat blocking last week of November and into December. The pattern is already amplified, though consistently being overwhelmed, but this looks set to change as we head toward and into December. In reality we usually have to wait a little longer to get blocking in the right places for cold but December looks to have a good chance of some cold spells for now.

And here's the chart from November 6 1978...It's hardly a 'thing of beauty':

GFS is excellent longer term...it's like a massive spoke being stuck in the wheel of the trop vortex, and by the end of the run we can see this having a bigger effect on the strat vortex than we've seen progged recently.

50cm of snowfall yesterday in the high Spanish Pyrenees. What a huge contrast in the upper air anomaly temps between Iberia and NE Europe. Just an example of the strong block keeping much of Euroland in warm air and the buckling Atlantic Jet sending fronts and cooler air mass further well south. This is not normal. C

Reads thread. Looks great for cold prospects Goes away for a week Comes back. Reads thread. Looks poor for cold prospects Shrugs shoulders and goes away for another week.....

The North Atlantic jet shown from (gfs) below continues to buckle against the strong European Block. The latest ECM models shows a strengthening of the ridge by Mid Month. So robust it is , that the buckle in the jet sends it into almost towards Sub Tropic jet location. Its not really unusual to see this block at this time of year, however, the failure of the Polar Jet to push into Europe in its normal path is a notable feature , it should normally be powerful enough as we enter the seasonal change in increasingly upper air temp differentials to make an impact into the large block. (whether the weakening of the jet is due to GW is another subject ) but is being touted by some experts as a cause. Anyway, back to our longer range thoughts, still basically the same and a front loaded winter not being dismissed, even with this very warm Autumnal spell lasting till mid -month. Ridging of high pressure in the vicinity of the British Isles still being featured with colder weather for the last 10 days of the month.

That sums it up in a nutshell! This thread by it's very nature will have a cold chart from the depths of one of the model suites showing something cold posted up daily. It is the hunt for cold after all! I know what you mean though - a week ago people were salivating at the prospect of something perhaps showing up around mid month.....fast forward 7 days and all we've got from day 1-10 and perhaps 15 is atlantic driven autumn weather. Nothing wrong with that, it's not even winter yet. Just as summer has a peak period for heat from around the end of June to the middle of August, winter proper is really the last third of december to the end of february. Plenty of time for nirvana!

Performance varies, but currently for the NH at day 5, ECM wins, UKMO 2nd, FV3 third: At day 10 FV3 first ECM 2nd and GFS and GEM tied third: Re the comment about snow forecast from @WalsallWeather123 you'll see a lot more charts from GFS then because precipitation and snow charts are publicly available, they aren't for ECM, UKMO. And if the snow event is actually going to happen, shorter range models like ARPEGE and HIRLAM then come into play.

ECM pretty interesting at Day 10 is this the start of the blocking that wedge building in Iceland area

Yes that big low does seem to be pushing up a ridge at T240: Bigger story maybe the stressed nature of the vortex, another option the JMA at T192: Quite a few different options in the day 10 range, yes most of the blocks aren't in favourable places for UK cold, but I'm musing here that this broad setup could change at some point quite quickly, wouldn't rule out a sudden switch to cold well before any strat related evolution.

12z showing incredible JS meandering....this is extreme. Straight Southerlies from well into the African Continent. Which means northerlies from S Greenland for Canaries..... BFTP

Let's throw a spanner into the works of the pv on a more serious note the charts today from gfs/gefs and ecm 12z are a lot better than yesterday's wrt more amplification.

Ah! The all important wedgy. Oh we have missed you

EC picking up a new signal for high pressure to be more pronounced than seemed likely only a few days ago. Still an angry looking low sweeping into the North Atlantic by day 10 but perhaps the Azores low will be of benefit ? Edit Absolutely amazing call from Exeter if this run is on the money as they have been suggestive of HP having more influence mid month!!

The GEM at T240 showing a huge block over Scandi, good to see this further north than recent model output, puts pressure on the vortex, which we need to maintain, meanwhile southerlies for the UK:

It shows where we currently sit that we can’t even find gefs members that actually show wintry conditions for most of the uk ..... However, its early November .......... and there is little to add beyond that short statement !

When it predicts snow it's the only model you see on here

Latest GFS now showing what the earlier ECM run had and that's the strengthening of the European Ridge by Mid -Month with fronts heading back west from the UK . From a colder point of view we will need this process to develop further with the ridge starting to head poleward and the buckle jet continuing sending Atlantic trough/ lows in the direction of Iberia. Now we wait to see if this evening ECM run continues with this support ! C

Outlook - unsettled and very windy at times. The key player being the upper low in the eastern Atlantic The 500mb and surface analysis for midnight Today gets off to pretty grey and dank start with plenty of low cloud and mist over central England with some thicker cloud to the west with rain over north west Scotland and bits and bobs elsewhere. Where the cloud thins and breaks over central and eastern England it will become quite warm But during the day the now weakening cold front will track east, but more to the point. so will the frontal system associated with the deepening low south west of Ireland, which brings rain and strengthening winds into the south west and N. Ireland by lunchtime and further east during the afternoon. Overnight the rain, heavy at times, and strong winds progress further east giving a wet night to most areas BY Wednesday the UK is covered by a myriad of fronts so a very wet and windy day with strong winds, perhaps gales along the south coast, and maybe clearing somewhat in the south west later. Over Wednesday night and through Thursday the general rain area clears away to the east but the low in the Atlantic is taking closer order and another front tracks east into western regions giving another wet day here whilst it stays dry in the east and relatively warm Over Thursday night further troughs have tracked rapidly east from NE North America to merge with the main trough to our west and by midday Friday there is a complex area of low pressure to the west of the UK with a deep surface low near the west coast of Ireland.so it becomes increasingly wet and windy, with gales in exposed areas. The main area of rain should clear through Saturday but squally showers will be the order of the day, with maybe some hail and thunder in the mix, in the fresh westerly wind.Temps around average And the NH profile at T120

Latest tweet from Matt Hugo says that the Nov ECM seasonal maintains the risk of Northern blocking throughout the winter and more so as winter progresses. So perhaps not front loaded after all.

We are on the cusp of something special here guys,while we have strong +ve height's in our vicinity(looking at the gefs ens) only time will tell for a retrogression/displacement of this and bingo i will settle for cold and frosty days in the next couple of weeks. btw,where is frosty?

Yes February has failed to deliver to consistent cold throughout, mind 2010 and 2013 were consistently chilly. First half of 2009 and 2012 was notably cold cancelled out by mild second halves, 2005 was a bit like 2018 a milder first half cancelled out by colder second half. Even 1991 fizzled out mid month. 1986 was the last time we had cold throughout the month. I feel Dec 2010 was an oddity a once in a lifetime type month. I was however more encouraged by winter 09/10 a proper sustained winter overall, it started in mid December and didn't relent until well into March - many sceptics saying we won't see cold winters again.. March 2013 was preety exceptional as well. As for this winter, I will give some musings in a couple of weeks time.. I can take a mild start provided the cold arrives in time for christmas, preferably the cold sets in about 14/15 Dec, 2009 was excellent in this respect.

Whilst the immediate prospects perhaps don't bode well for a quick exchange to something colder, the trend appears to be for a more amplified flow through next week, and whilst we may have to endure a period of mild southerly airstream this would aid warm air advection into the Pole, which could force the trough back west and allow it disrupt, heights would then likely build to our north and hence a colder pattern for later in the month. Patience I feel is needed. Perhaps take a break for a week and some of the colder building blocks may start to come into the reliable timeframe. Rather have this pattern now than in a months time.

I can't wait for NW's upcoming snow-chasing trips to Day 10...I have my ticket already!

@Midlands Ice Age - there are countless studies which contradict your view that it'll be a 'few centuries' before anyone has to worry about Ocean acidification, including many of the effects being felt already. The very report you're apparently quoting, clearly doesn't match your view. The graphs you're showing only go up to 2100 also, so what conclusion would you expect people to come to when you come out with a statement like that and have apparently nothing to back it up? We've had this conversation before, you talk about your scientific background often, but then seem to go about science in a backward way by continually hunting to find evidence, no matter how tenuous, which supports your view. That isn't the way science works. From the IPCC report: The above shows the risk assessments in the IPCC report, and for each outcome, by 2081 to 2100 there are shown to be significant effects. How does that fit with your assumption that there will be no problems for centuries? And I could go on, and on, and on. Countless parts of the report, images, paragraphs, graphs which all contradict your view.. But somehow, you're ignoring all that, having apparently read the entire report and have decided to jump to an entirely different conclusion, hmmm. For those who haven't read them, the reports are here http://www.ipcc.ch/report/ar5/

GFS showing more in the way of high pressure influence longer term this evening.. Hopefully a sign of things to come..

Morning All, a damp, overcast start to the day as all the heat form the evenings explosives warmed the air (as Matt noted too!). Currently 12.5 °C with RH 94%. Ok door handle, don't feel sad, their loss is our gain..

So fed up with people telling me what I can and can’t do, fireworks should be banned, it upsets my dog, the poppy offends me, don’t call me male or female I’m a door handle, on Facebook, I’ve decided to take a break and deactivated my account. So sorry, you’ll have to put up with me a lot more on here now. lets hope the weather gives us some fun over the next few weeks

Looking a this morning's GEFS and EPS mean anomalies, along with last night's NOAA, they show no indication of any significant change in the medium term. With twin vortex lobes Franz Joseph/norther Canada and associated trough down the eastern/central Atlantic a strong westerly upper flow is maintained which is modified somewhat in the vicinity of the UK, courtesy of the ridge to the east. Thus remaining unsettled but with a NW/SE bias over the UK with temps generally around average.

I think perhaps December 2010 has skewed some peoples expectations of how winter should be in the UK. Living on the south coast I never really expect to see cold and snowy synoptics before Christmas. If I do I look at it as a huge bonus but I certainly don't expect to see them. In this part of the UK December is most often an extension of Autumn rather than a winter month.

Indeed Sleety, little sign of the slug giving up anytime soon.Classic +NAO stuff ,and we know full well that these setups can last quite a while so thank goodness,as you say, its early November. As an aside, i know there is interest in the meto updates, and they continue to paint a colder outcome later in the month,but i noticed the BBC monthly updated yesterday suggest westerly, south westerly winds right out to the end of Nov/beginning of Dec, as a caveat they say there is a 30& chance of dry settled weather at the end of Nov but do hint at some very wet weather at times.

Its a very slow moving pattern, atlantic locked in place by the stubborn heights to our east, hence a predominantly unsettled trough dominated outlook for the foreseeable, the milder uppers will slowly be lifted out as the trough inches ever so slowly further eastwards. Ripe territory for secondary low formation - cyclonic conditions, some heavy rainfall in places - generally a poor outlook for sunshine and fine weather. Longer term - jetstream profile looks buckled and amplified and there is every chance we may see pressure rises over and near the UK as we move further through middle of the month opening up the chance to something colder from the north later on. Early-mid November is a very uninspiring period of the year I feel - I can't remember the last time we had either a colder than average first half, or a mostly settled fine foggy cold one - a long time ago. Ode to November - No fun, no sun November! lots of adjectives beginning with letter d as well - dark, dank, dismal, dreary, dull, drizzly, drab...

Re:- my post earlier about more amp in 24 hrs the 18z gfs compare yesterdays>todays 216/192 this block is stubborn,will it be our friend or foe? friends

At this point in 2010, the coming big freeze still wasnt showing, GFS was still saying Atlantic influence, it happened in a very short timescale and was very interesting in here when the first signs showed.

Oh! Since when did the gfs know anything?

Sorry to digress but surely you'd take a December 86 in order to achieve a Jan 87!!!!!!!

ECM day 9 interesting...

Caveat being he is using GFS !

I've got a bet on you being back on in less than three weeks

Yes it looks like an increasingly Atlantic influenced setup for us going into the coming week as the block to the east loses it's grip. We see at day 5 on all 3 main charts the low pressure parked nearby with a brisk westerly flow and rain bands moving across. Looking further on no sign of anything untowards by day 10 on the mean charts. Low pressure towards Greenland extending a trough southwards and the usual Euro heights but now with the jet running much further east across Scandinavia.Thus an ongoing broad westerly pattern with temperatures around or just above average with some rain moving in at times.

Why? They're the experts and have access to things that we don't, the lack of patience on this forum is astonishing!

6Z shows Euro heights persisting right through to the end ..

It's getting needlessly snipey in here. I know it's a hot topic but try to keep it civil, folks.

Perhaps if we throw more stones we wouldn't have a greenhouse!!!

19 day's blank, 185 for 2018 60% Solar flux 68

https://twitter.com/webberweather/status/1059473581678231552 West QBO has descended below 30 hPa but the lower stratosphere remains in an eQBO favoring tropical tropopause upwelling & upward propagation of Kelvin Waves to the westerly shear zone. Worth re-iterating that SSWEs occur most often during an eQBO >> wQBO transition.

the dreaded euro trash or whatever you call it high seems to becoming the dominant feature at the moment..Thank goodness it’s only early November and not early January,if you were looking for cold and snowy weather.

18z GEFS control run - P4 - P13 P20