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Do you know I was on my way to breakfast thinking exactly that- Also as I mentioned to @Seasonality the other day Whenevers there uncertaintly around blocking towards greenland more often than not the models back away, however when the GFS in particular strings run after run together then upgrades are inevitable - & when was the last time we strung such a lengthy period of blocking runs together - 2010 Now the trend in the last 24 hours is to ease the blocking on day 6-8 over greenland as it holds in situ over iceland - however as we head day 9 out to ~13 the renewed pulse of blocking is now securing the greenland block but also another cross polar high is beginning to develop thus supoorting the longivity even more- As of today ive counted about 6 or so runs where we are blocked & bitter cold all the way through to the end of the run... Best S

Three observations from me tonight: 1) Still in line with my thoughts from the other night, im not convinced on Greenland height rises just yet - GIN corridor seems more realistic at this early stage, and that’s partially because.... 2) I don’t really want Greenland height rises at this stage given such a mild 2018 across Europe so far. I fully expect synoptic evolution towards 2010 type scenarios as we progress into winter (and late 2010 has been a favourite for me in terms of analogues for some time, albeit I think we approach this with a slightly delayed timeline - but for the first time in a long time, I think long range NWP with its emphasis on northern blocking is not far from the mark) 3) Everyone needs to start appreciating how valuable the contributions of @bluearmy are in this thread. Nick has consistently through the years, whilst always being a cold seeker like most of us, offered an incredibly balanced view of what’s going on in NWP, and we should all count ourselves lucky that he continues to post his thoughts for us. (I promise I was paid no fee for this...) There has, as always, been a lot of conflict in this thread in the last 24 hours - and sadly that has just become a matter of fact in this thread as we get to this time of year. And I would hope that we can maybe move beyond that this year - we are blessed with some ridiculously knowledgable people in this thread and I would like to hope that nobody, no matter how experienced, is scared away (or frustrated away) from offering their thoughts this year. Each and every thought contributed is just as valuable as any other, given that for the overwhelming majority of us this is just a far too obsessive hobby and we are all looking for one thing - a happy snowy ending. ————— To return to my thoughts from the other night, and returning to point 1) - the reason I am not concerned about whether we get cold/snow in the coming week is that, as per my post earlier this week, the upcoming pattern (near record breaking Scandinavian high and, as GP aluded to earlier, Aleutian low to tow), the damage to the fledgling vortex will be near irreversible, and the longer term results across the northern hemisphere should be beneficial to the cold and snow enthusiasts among us. This is clasic wave 2 precursor stuff, and regardless of a rebounding QBO, given the current disconnect between the stratosphere and the troposphere, should play havoc with attempts from the polar vortex to set up its usual happy shop across the arctic. In short - I’ve not been this excited about a winter since 2009/10 - and this is just the beginning...

If you hadn’t looked at any previous output this autumn (especially FI) and this was the first run you had looked at, then you would say that in the first half of the run the building blocks are in place and it wouldn’t take much for a notable cold spell to develop. That doesn’t change by looking at the second half of the run. It won’t take much to change from retrogressive nothingness to something far better. When the Scandinavian block is in place, then we need to look upstream and get the right split flow from the tip of Greenland to reinforce the block. Small margins that can change in the coming runs. And nice to get rid of the mild drizmable weather of today.

A bit of an update this morning from our forecast team. Outer perimeter snowfall model has snow setting in here on Sunday night with a total accumulation of 11cm and temp down to -12c at top station by Wednesday morning. So that's an encouraging prediction for the resort planner, but greater snow depth needed to start work on the seasons ski pistes , but that's a start. They inform me that a increasing feature showing on their on single model at 144t-168t is the formation of another westward propagating low formation / trough in the Northern European plain/Southern Baltic region. They seem to think this could be the catalyst to advance the Arctic front into the British Isles by months end ( one to watch ). Regarding the shorter term models out 144t, UKMO seems the best solution from what they see and again are surprised at the ECM speedy evolution to a veer in the flow. Their own longer term charts still show strong ridging towards the Arctic with possible Omega Upper flow (300mb ) block developing a more meridional flow early December with strongest flow into NE Europe and rather weak Atlantic jet still showing persisting, but that's a long way off. Will get a latest snow projection later today, so will try a see what that has in store for UK , however , still in the out perimeter predictions. Its going to be great model watching in the hunt for cold but pleased with this morning update from over here .

The GFS sequence is again probably the wildest cold run out there I think ive ever seen in terms of blocking ! The AO for 204 onwards will be sub -4 & the NAO tanked as well- You probably couldnt imagine better charts than this - !! Also UKMO fully on board as well out to 144 with snow - probable SE on day 6- Incredible runs... a

So, with the first few account restrictions in place as of this evening due to posts in here, now's maybe a good time to remind those who post the following sorts of things, your cards are marked.. Posting solely to generate negative/extreme reactions Over-reacting to model output/other peoples posts in such a way as to disrupt the thread Jumping all over and accusing people of trolling just because they don't agree with you/the consensus (please report people you think are trolling, don't respond - we will deal with it) Being ultra-defensive As a general rule of thumb, please just be nice - we're all here to enjoy discussing the weather.

GEFS 6z are tremendous!! And to add to that METO update now suggesting cold dominating out to mid Dec with only a small chance of an Atlantic attack which will likely be short lived even if it does happen. Sounds very much like this huge blocking high is going to be the dominant player for quite a while!!

Well blocked and bitter cold we are at the end of the FV3 6z, here at T384: Relentless!

In the run up to this cold spell The ECM operational has been progressive in every sense of the word - Initially no Easterly, then a fast toppling easterly - every transition from 12z - 12z the following day has been the 144 chart portraying a much better output than the 168 chart the day before - Its been an ever revolving door of progressive nonsence replaced each day by some conformity to the UKMO / GFS- With the alleged atlantic attack day 9/10 this is a double edged sword & people need to have a close understanding of the pros & cons- At atlantic push will often be modelled as transitioning North when infact the real time data will end of showing it moving East - So having the atlantic displaying 'motion' at days 9 could well be a great thing as that motion may well support the advection of cold from the NE ( like the 06z ) Things finely poised - My model of the eve - UKMO ... Especially 144 - look how different the WAA is over greenland V EC op- EC op will be a general mild outlier V the clustering- S

Good post and I think the problem is people see the easterly and this has raised some undue expectations . The easterly doesn’t have suitable cold uppers esp this early in the season. The main interest could be what happens afterwards . At the moment the models are playing around with the block and the exact trough set up to the east . There’s plenty of cold air there and it’s getting the right jet track to get that sufficiently west. The main thing is to get the block and then wait to see how things develop , plenty of time for changes .

I'm sorry but that is possibly one of the silliest posts I've ever seen on this forum. You need to take a look at the archive charts a few days ahead of the winter of 62/63.

EC 96 Strong Easterly flow, 526 Thickness ~ -7 uppers says to me sleet & snow showers for me ( odd pocket of -8c )

A little focus of the various operational runs at 120 hours: GFS 00Z UKMO 00Z: ECMWF 00Z GEM 00Z ICON 00Z They all seem to be in fairly good agreement with Easterly No. 1 next week. (I say No. 1 as further Easterly outbreaks are very possible when you get blocking to the North). For the UKMO, had to use the Meteociel chart for its 850 hPa temperatures due to these being unavailable to Wetterzentrale. While they do essentially show blocking High Pressure developing to the North and Atlantic Low Pressure sliding underneath it to our South or South-East into mainland Europe, there are some differences. The GEM has the Northern UK High a little further South compared to others with higher heights affecting more areas of the U.K. The cold pool to our East over mainland Europe just about scrapes the South-Eastern area of the U.K. with an area of positive 850 hPa temperatures affecting Northern England, Northwards. GEM is known apparently for either under-estimating or over-estimating the cold or warmth of the 850 hPa temperatures. Whether this really is true or not. Though I still feel the reason for it having a more widespread area of milder upper temperatures is due to that blocking High not being quite as far North. The other models runs have either Easterly or North-Easterly flows with areas of -5*C, and slightly lower, 850 hPa temperatures affecting more areas of the UK via the cold pool to the East with none of the 1*C or milder 850 hPa temperatures affecting any areas of the U.K. Those milder 850 hPa temperatures are locked away to the North of the U.K. within the High Pressure centre’s circulation. The 500mb heights are somewhat lower with greens and turquoise colours generally affecting Northern England, Southwards. This particularly so on the 00Z ICON, where even Southern and Central Scotland are affected by the greeny colours. Apart from the GEM, thanks to these lower heights along with 850 hPa temperatures being around -5*C to -8*C in places (especially on that UKMO chart where -8*C’s clip far South-East of England), this would probably provide enough instability for some showers. Some of these could wintry at times, even to some fairly low levels. Possibly some wet falling snow where showers are heavy and where they become more organised. Though they’ll likely be mostly quite light or moderate, with the heaviest ones towards Eastern areas. Would ideally need even lower 500mb heights and 850 hPa temperatures to make the situation even less marginal for snow and to help increase chances of more potent heavier wintry showers. The warmish North Sea temperatures, especially towards Southern areas, may though help in favour of producing some fairly beefy showers. Finally, the exact placements of the Northern UK High and the areas where Low Pressure slides under these, aren’t all quite the same. The likes of the ECMWF, for example, has more of a stretched West to East orientated blocking High over Northern UK with the core of Low Pressure generally more concentrated to the South-South-East of the U.K (the model where High Pressure is also more prone to getting knocked away further East, still with some of it getting cut off to our North). This, though, resulting in more of a direct Easterly flow as opposed to the likes of the GFS, ICON and UKMO (and even the GEM). Low Pressure on these other models (accept maybe on the UKMO) is little more further East over mainland Europe with generally more rounded Highs to our North), with the flow steered more from the North-East over the U.K. Although it’s easy to get excited by what’s on offer further on in these outlooks with some of us unstandably hoping for a more potent outbreak of cold weather to occur, would say the likely upcoming Easterly may provide some wintry interest. Even if it looks to be rather marginal and the Easterly could just be a bit of a dull, gloomy, chilly affair at times. Plus, with some differences between the models at day 5 (120 hours), as illustrated above, then expect some further tweaks to the upcoming week. The 00Z GEM seems a little on its own with the Northern UK High being somewhat more in control at 120 hours. As such, probably the run that’s least likely to happen (but you never know!). The general broad pattern does seem to be their, however. Blocking High Pressure and high heights to our North - Low Pressure and lower heights to our South, with a fairly potent Easterly quite possible over the U.K. Maybe cold and unstable enough for something a little wintry. Which would still be better than nothing. Settling snow however, unlikely.

If we are going to be looking within the next 5 days on the GFS model, it's also a good idea to look back at what the GFS was modelling for today back on Sunday. Sunday 6z and Today 6z: I must say the GFS has done exceptionally well within the 120hr timescale for the last few days.

Weren’t yesterday’s 12z’s also a bit of a downer before the pub run bounced it back? I’m just saying it’s probably too early to write any cold spell off just yet- I’m sure there will be some tweaks but it’s misleading to suggest that the semi cold spell next week is off the cards or indeed the building blocks for December are off the table. everyone remain calm!

Watching the models try to come to some sort of agreement for what may occur toward months end is a far more relaxing experience in the ' comfort 'of mid November than say, the fag end of February. A lot of talk of 'slow burners' with 'building blocks' being put in place. That may well and hopefully be the case for a proper freeze towards months end and early December. It so often seems the case that so much of winter has past before a model scenario like this starts to play out, you are left thinking that we just don't have the time for a 'long route' to cold to play out. On this occasion if it does go 'bust' on us we can view this as a good start, and fingers crossed a trend this winter that will at some point pay out with snow by the bucket load!

The control run!

You know the Winter season is approaching on NetW when people are writing off Winter before it's even started. Wonderful thread, as always, for any budding psychiatrists to pop into

Not sure why people are writing this cold spell off on the back of a single GFS op run at over 200hrs away? Para is very good by the way GEFS 12z mean also very good, doesn't side with the Det run at all

Chart of the day from parra that is one hell of a -NAO/AO signature.

We need to be looking West in these scenarios. At T+168 the potential is still there

IF the Atlantic does try to make inroads in FI always the possibility for the fronts coming in to meet the cold air leading to some snow like what P6 shows and also P11 (more marginal) another IF is the first attempt at getting the high to Greenland, P4 weakens the first but goes for a 2nd attempt later in the run P10 destroys the PV P14 also has a second go at a Greenland high Ensemble graphs still look fine for here Kulusuk (east Greenland) still signs for pressure to rise then a bit more scatter later as to be expected Puppebu (arctic) again still on track for a slight rise in pressure think the signals later on for lower pressure could see those lows diving south / SE possibly into scandi or towards us Reykjavik also pressure rising and again those that lean towards lower pressure later on might not be too bad if the high has moved to Greenland by then Think the area to focus on first before going too far ahead is the movement of the high from Scandi > Iceland >Greenland.

Evening all, all snow cannons in operation on the mountain this evening with current tempo down to -4c in village. The impressive UKMO again showing consistency out to 144t with each run getting colder through all layers surface to 500mb level. Not sure what to make of the latest GFS run, think a correction to a more backing flow again in the next few runs as our experts still think another low formation as indicated in the above post will start showing in the bigger models shortly. Snow portal results today have some spikes for parts of England and Wales by next Thursday ( 200-150m ) Quite a change in one week. Keep you updated over the weekend as our snow portal service comes into action. C

I just wanted to say: I'm happy this forum exists. The majority of members on here are supportive, friendly, and have a great sense of humor. The amount I've learned through other's knowledge is brilliant, and in most cases, I rely on this forum and it's knowledgeable members much more than mainstream forecasts! Whenever there is Fantastic charts appearing on model runs (Especially recently) , The atmosphere in here is buzzing & full of excitement. This also applies to the model output threads. It's strange... It's as if I can channel my excitement thorugh seeing others who are equally as excited. It almost makes the time go faster before a special weather event (I.E. 26th of may 2018, the beast from the east in february, etc.) occurs. I may have mentioned this before, but I have very mild autism & ADHD, And I''m very close to finishing school (nearing my GCSES). This forum helps me contain my excitement throughout my daily life. I hope this forum continues as it is right now for the foreseeable future. Thank you everyone.

Some good news ICON back on board again.

Going to be a long winter if people start writing it off 2 weeks before it begins. General picture in the model output remains the same - Plentiful blocking and a heavily disrupted PV. Ignore specifics beyond a week ahead and concentrate on the bigger picture.

Me earlier this afternoon: "The GFS doesn't seem to default to zonal in low res anymore" GFS: "Hold my beer"

Yes @BLAST FROM THE PAST @shaky The initial progs from the East 'mean' was about -2 to -4c, this was about 3-4 days ago- then slowly as always happens in Easterlies the heights lower & the 850s are trimmed out- So the above numbers became -4/-5 then yesterday a few flirtations with -7c. Today the upper air cold pool has at day 5/ days 6 small pockets of -10c over the near continent with the -8c line making a tiptoe into the SE ( Think ICON gets it into midlands ) - I think the top out is -9c which is 1c away from Nov 1993. In terms of PPN - the prospects of snow away from the downs has increased but probably sits 50 / 50 - *but* as that low creeps in the fact its really shallow means evaporational cooling could play a part- Im 70% confident of seeing snowfall at home next week & 30% confident of a dusting.... S

I've not really been disappointed with any of the runs this week There's been the odd run I've thought hmmmm and arrrrrh. Today's 06z is overall good. I'm not convinced about the low pressure making it milder towards this Sunday like a video forecast I've seen. If that is the case it seems a very brief milder interlude according to this morning's 06z. I can't see a low pressure for the weekend It's probably me. And I'm sure I'll be corrected if I'm wrong. Next week Thick freezing fog. Or crisp clear days for my neck of the woods I don't mind either. As we move into next Thursday I'll be on chart watching like a rash. As what's at T+204 hrs now Will be around T+72 hrs then With a lot of differences I'm sure I don't think I can post much more till next week now.

These charts from 1st December 2010 preceded some of the most memorable winter weather seen in December in recent years: We all know what followed in 2010. So when I saw these charts from the GFS showing a possible evolution for 01/12/2018 I couldn't help making comparisons..... i would say they hold at least as much potential, if not even more, for a cold and wintry December this year. Very exciting prospects indeed! Now all we need is for these conditions to verify..... What are the chances, eh?

Apparently one of our viewers phoned in and said they had been told winter Narnia was coming... Don't worry, Winter Narnia isn't coming.

Not entirely convinced of the increasing trend of the Atlantic push the models have started over recent runs, the EC det. in particular seems to be taking this scenario by the horns by not retrograding the block as far before it retreats back into NE Europe and Russia to allow Atlantic troughing to take over. Handling by models of blocks like these still not to be treated with too much confidence IMO beyond day 6 or 7. The 12z EPS det for London looks on the mild side for London at least: more runs needed to be confident of where the block positions in medium range, whole N Hemisphere 500mb seems to be retrograding upstream too, expect some wobbles, but deep cold pot of gold to the NE out of reach for now.

Good news is that the GFS 18z is steady as a rock at 0 hours

Oops sorry I was looking for the hunt for cold thread but can only find this moans and banter thread..

ICON now progging -8c getting into SE with some PPN attached

FV3 run verging on epic territory at T276: A recurring theme now on the better runs is to push the entire trop vortex to the eastern half of the NH, creating the ultimate cold pool to tap in to.

Yes daniel..the azhp..wants to shake hands with that large pac-waa/ridge.. Top stuff!!!! @vortex @carved !!!

My word.. Vortex sliced exactly where we would want it to be sliced!

the 12z run in deep FI is different but even on 1st Dec there is plenty of -4c air over U.K. with a SW’ly airflow. Indeed that changes on 2nd but looking west the ridging in Atlantic is there for a northerly to quickly follow. And over the US it’s HP all the way....the Atlantic would be in shutdown mode again...jetstream all over the place It’s going to be a ride.....and what a ride ! BFTP

Haven't time to browse the whole thread but has anyone posted the parallel yet? Sticking to its guns at D9. Stunning.

@AppleUK 123 another piece of advice from someone who has been on NW since 2009. If you are getting hung up on the weather take a break as a lot od our seasoned posters do. This is one od the best openings to a potential winter period that I can remember and it's still autumn. Try not to get hung up on each run. Otherwise you will have a horrendous winter. Learn from the few on here on this great thread and take time.

Trough? I know Netweather can be notoriously sketchy on terminology, but even so... Anyway, the GEFS mean for the start of meteorological winter is great (as it has been consistently):

Indeed NWS. To me, nothing much has changed - blocked and cold for the foreseeable.

Good grief talk about over reactions..!! You would be forgiven for thinking we had a ripper of a Greenland PV and raging +NAO.

a travesty? when has any model showed disruptive snowfall before T192 ????? this set up in late dec onwards would probably deliver snowfall. its going to be a week short of meteorological winter commencing off the back of a near record warm autumn ……………...perspective required

Hello another stonking set of ensembles. Number 6 is a 1979 redux

Ha all about the mean Also just logged into the AO ENS Never seen lower than -6 before !

Oh my! How’s that for a Stonking set of ENS Some pretty cold runs in there! On balance there are a few rather mild ones as well, somewhat of a split from around the 27th, but majority look cold to me...?

As soon as I saw that Arctic HP appear I thought 'oh boy, here we go' I do believe that is the GFS saying 'up yours, son' to the EC46

I think this is the first time we have seen an Arctic high thrown in the mix. That would surely spell game over any Atlantic driven weather for the foreseeable. Pretty cold 850s into SE on UKMO,