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I swear this was the model thread...can we move on please and stop ruining the thread for others?

I don't buy any of this defeatist Malarky tbh. Nothing is showing mild mush and everything is all to play for come January. I remember a few making comments about fantasy easterlies etc just last week. Which were never on imho. Equally talk of 4/6 weeks is barmy. The gfs para shows clearly what is possible. I am not talking about the fantastic uk Synoptics, but it shows considerable wave activity and warming. It shows a collapse of the pv. It's also not alone and quite a few ens from the operational supported this as we moved into Jan. It needs to be watched carefully.

Evening All- So as we head into the festive period & peoples breaks - the weather sadly is taking a turn for the worse, the vortex initially displaced NW by around 500 miles will wobble back SE & take a westerly swipe at the UK with 1 maybe 2 atlantic storms rolling in- In terms of a white xmas,Glasgow is the main favourite with maybe Belfast a moderate outside bet as its close to the colder flow- It appears that 'snow' in heavier showers later in the day as the coldest uppers move in would be the best shot- unfortunatly the wobble of the PV is set to retreat back NW as the quasi stationary high pressure to our SE develops & moves north again- Whilst this is favourable for the UK in terms of keeping the wind & rain away we must not link this with the overall NH pattern changing- quite the opposite infact- looking at the zonal wind along 60N @ 10HPA we are not at peak yet, peak date is around the 23rd Dec @ about 60M/S ( remember climo for this time of year is around 35M/S ) - so we are the thick end of double the climo norm- what this actually means is theres very unlikely to be any trop > Strat disconnect & the 200mb jet will follow a very sinuous flow along ~ 60N - * Teleconnection AO/NAO couplet expected to be top 10 positives ever recorded with AO close on +5 * Strat signature reminicent of 2013 & 2015 * Recovery time to AVERAGE metrics in the stratosphere ( & net teleconnections ) - 2 weeks, 3-4 post propergation. * Chances of a greenland high are near on zero for at least 4 weeks. * Chances of a Scandi high are near zero for 2 weeks * Chances of a mid atlantic high - low for next 10 days, possible slight amplitude thereafter. January expectations: The worst ( warmest ) Jans post 1979 are as follows 2007- 7.0 2008 - 6.6 1990 -6.5 1989- 6.1 we see the following Merra zonal wind data- * Sadly our closest match is 88/89 ATM-note the zonal wind never really gets below climo across Jan with no warmings ( remember our start point will be around 50M/S which is very close to the above 4 start points- conversely our coldest months 1979 - -0.4 1985 - 0.8 2010 -1.4 1997 -2.5 we see the following maps- The top 3 all have significant warmings reducing the zonal wind - Also I have looked at the specific dates of the top 3 in terms of when the warming started (commencement of zonal wind deceleration )to see of these were trop lead - 1978/79 occured on 14th January & the 500mb anomalies 5 days prior to the warming - we have a big wave 1 pacific high ( -EPO) 1984/85 occured on the 17th December - & the 500 height anomalies 5 days prior to it - we have a big wave 1 Russian High- (-POL) 2009/10 occured on 10th Jan & The 500mb height anomalies that preceeded the warming- note the very strong 2 wave pattern over the atlantic & Greenland - so in terms of SSW linked into cold jans looking at the zonal wind V the 500MB plots the trop response to a trop induced warming was instant - the the zonal wind slowed down & reversed So its pretty clear that our start point isnt good heading into Jan- The indications are that there will be a peak ( as mentioned ) around 23rd/24th dec with a decline to the 3-5th down to about 45-50 M/S thereafter we have 2 junctures- 1) No strong wave activity enough to break strat PV down- leading to an above average zonal index for Jan @ 60N - no significant wave amplitude so no Greenland High- only real chance of cold from scandi - NAO/AO loaded positive- trending towards neutral-positive (IE not quite as bad) 2) A trop induced wave (2) SSW in week 2 -3 of Jan, similar to 2009/10 where we saw results quickly - it was also a WQBO year as well - So in a nutshell, The early 'form' leading us to the conclusions of a front loaded winter have been replaced by a structured vortex on a par with 2015- We are now preying on a trop lead SSW to backload the winter in our favour. No SSW is 'likely' to mean winter is already over in terms of HLB- leaving the scrum for a MLB locating favourably for the Uk & we all know thats a very difficult block to support any snow for the UK. * This could be the worse winter since 1989 ... S

Very quickly just gone through the ens member and around 50% have A blocked Atlantic with struggling pv and many Greenland highs as we go into the beginning of January. At this stage I don't give a monkeys where things are positioned for us, nor whether we have cold from it or not. It's purely the general trend.

here's a thought.....rather than clog up the thread with "Your post was amazing, super, brill etc etc etc" type posts, how about just 'liking' it and/or sending the poster in question a nice pm instead?.....also rather than posting words to the effect of " stop quoting long posts as they clog up the forum etc etc etc etc" how about just sending the poster a quick pm?.....it would stop the thread going off topic and also save the mods/hosts time in having to reply with posts like this........food for thought

Nick Finnis weekly Medium-long range outlook - 20.12.16 With little signs of any sustained cold and wintry spells on the horizon, certainly for the remainder of 2016, it’s perhaps worth looking at what’s driving this pattern which is so hostile to high-latitude blocking and the UK getting anything more than just fleeting shots of cold zonality behind deep lows passing north of Scotland over the coming days. The upper pattern in the northern hemisphere is rather unconducive to a -NAO and -AO. We are seeing the NAO and AO reach high positive values. This partly down to rapid intensification of 10hpa zonal winds with forecast cooling of temperatures to near record levels in the upper levels of the stratosphere in similar fashion to Dec/Jan 2015. Currently the strat PV is elongated as per ECMWF 10hPa chart below, but the same model forecasts a tight / symmetrical vortex circulation by day 10, almost as strong as last winter and there doesn’t seem to be a piece of guidance keeping it elongated, or purturbed. Though there are hints that there may be some wave 1-2 attacks down in the next few weeks, particularly from Europe/Scandi area and EC ens is also hinting at strong Gulf of Alaska ridge on current guidance, though they may not be strong enough to induce anything more than another elongation /stretching of the sPV. We are in a period of largely low AAM regime in which is also generally unfavorable for wave-1/2 amplification on the Pacific side, however, there is a Pacific wave train evident looking at 500mb guidance which some model forecasts maybe missing. In the longer term what happens in the stratosphere is crucial to how the rest of the winter pans out. But in the shorter term, the best opportunity for a pattern shake-up is likely be reliant upon MJO forcing. As those who follow the daily MJO forecasts from all the models, GEFS has been keen to move the MJO out of the circle of death (COD) into 8/1 – which is conducive to blocking shifting to high latitudes and possibly a colder pattern for us. Other models are less keen to come out of COD, EC notably, but good chance these models will offer a more favourable look into Jan. In fact you can see the progression of the wave eastward on the latest CHI-200hPa forecasts. However, not everyone buys in the MJO driving the pattern. But with the strong PV not likely to break down easily anytime soon, this may be where we have to look for something to shake up the pattern. For now, MLB returns on the seen in the medium range after a bout of stormy Atlantic zonality, so strong chance its back to anticyclonic in the New Year:

Well it was nice knowing you all.

CC I enjoy your posts on most occasions but your are abrasive which is an odd way to have a healthy debate. Disagree by all means but constructively helps all to learn. Season of goodwill and all that?

After 20 years of model watching from the old mrf days onwards I'll keep calling thanks. Compare it with gfs at that time range and see. Particularly one of the many runs today that show the blocked Atlantic.

Stop moaning, it is what it is, at least we should see some night frosts and pleasant weather.

Gloriously understated To all my comrades peering out for cold weather ahoy, please do spare a model analysis or two for poor old Scotland. If the current run verifies these two storms are very serious at an awful time for those who may be affected. We're looking here at potentially damaging gusts.

Looking at tonights models and charts data etc there's enough to keep me interested ,and a nice straw to clutch regarding the possibility of high pressure setting up shop and hopefully as we enter January 2017 possibly pulling in some cold synoptics ,but at the back of my mind I have a dread of big fat euro slugs (terrible creatures ) just hoping they don't convince the met office high pressure to breed on main land Europe, just a quick joke ,one fat euro slug to another ,cheer up mate in another 4 months we are off too Iceland for our holidays ,well gang let's carry on with the search for cold and snow we have some hints on ecm towards the end of its run tonight and met office hinting of high to our West, and it's still only December the 20th ,game still and truly on ,cheers all .

Well I never... the observed MJO signal just jumped toward the Pacific 6/7 in a way that none of the models came even close to predicting! Could take until tomorrow evening to fully assimilate this change... to paraphrase on what GP said about a fortnight ago after a similarly large jump. Such developments will help with trying to get a split vortex setup sooner than many might be expecting. Note that I say help, not guarantee If we can manage such a thing, the cross-polar ridge may help to drive some wave propagation into the stratosphere. At 30 hPa GFS seems keen on trying to repeat the mid-late Nov sequence with wave-1 and warming moving into Canada (in the 16-24 day range, extrapolated) but had it not flattened the blocking to our NE in early lower-res (FI) then more of a wave-2 signal may have emerged. I know this seems overly upbeat and perhaps it is, but I've not been convinced by the long range models drifting toward the idea of the vortex having its own way. Though I am wary of the propensity for the Arctic, as it transitions from a cold desert to a stormy ocean, to encourage net rising motion there instead of net sinking motion, potentially changing the configuration of the major cells (Hadley, Ferrel and Polar Cells) from a three-cell to a two-cell configuration. In short, this would encourage storms to travel either within or close to the Arctic circle rather than close to Scotland for example. If such a change was to come to pass, mid-lat blocking would become our most common weather type. It's only a proposed mechanism that's awaiting critical analysis, so for now it's not difficult to play the idea down, but my resolve with respect to this has been taking a fair few knocks lately.

An increasing trend in my opinion. This is what members should keep an eye on. A straw to clutch onto which makes a nice change. Looking at the entire GFS run this instinctively looks the likely evolution.

A couple of pre-Xmas upgrades to share with you. Firstly the NetWx models have had a big update in the last couple of weeks, increasing the vertical levels by almost double and adding a new convective scheme, both of which have shown to improve various facets of the modelling. http://www.netweather.tv/index.cgi?action=netwx-sr;sess= http://www.netweather.tv/index.cgi?action=netwx-mr;sess= Secondly, we've just put a parallel viewer online for the GFS 2017 upgrade (due May). There's a standard and an Extra one, the link below will take you to the extra one if you're a full subscriber and logged in, otherwise it'll take you to the standard version. http://www.netweather.tv/index.cgi?action=gfspara;sess= Hope they're useful

One thing that's struck me in the shorter term is that the progression of frontal systems has accelerated so much as to limit the amount of rain across southern parts to nothing of much note. What with the signal for a strong height rise on Boxing Day it's possible that it will end up being a fairly tepid attempt at restoring water tables toward normal levels after the prolonged largely dry spell of the past 3-4 weeks. Longer term, recent GFS runs are reflecting the enthusiastic nature of GEFS with the MJO but only if/when the other models start to share that enthusiasm will I dare to imagine any poleward ridges capable of acting like a brick in a washing machine with respect to the vortex. As last winter showed, it has to be something that dramatic to produce more than a transient sort-of-cold spell (which failed to deliver wintry precipitation in my far-southern location, let alone lying snow). Almost four years now since my last day of lying snow. Anyone who's been waiting less than that, what are you moaning about?

I'm not moaning but it's misleading when people post a chart at day 10 and say 'this has potential'. It's even more annoying when said chart doesn't even show said potential.

He said that the Pv was shifting over to, he didn't say it was over. It's his opinion and one that is not impossible to see. No one has the right to suggest that someone should give up this weather lark. Have you ever given an opinion and been wrong.? If he or anyone else sees something in the output they wish to voice then good on them.

A chilly inversion -

This is what I like to see maybe a change to a colder outlook is lurking.

Well 12z gfs p has just come out and looks very much like the t240 ecm at t240. It goes on to show the Atlantic completely blocked come the begining of January. All in all at this range that's all you can hope for. Plenty of potential from a blocked atlantic.

The anomalies this evening are firming up on the pattern they have been indicating for a couple of days now and they are on the same page so confidence level is reasonable high that the day by day evolution will fit within this frame work. Thus we have the retrogression of the Atlantic trough as the vortex becomes more centred over N. Canada although the ecm is keen to have a second lobe associated with the eastern European trough. The upshot of this is a flat upper flow across the United States with a fairly deep trough in the western Atlantic and continuing build up of heights south of the UK ridging north Ergo quite an amplified pattern across the Atlantic and this amplification is entirely dependent on the orientation and intensity of the two main players. This is illustrated quite well by just comparing the GEFS and ecm. This will not make a huge difference to outcome but any systems tracking NE with associated fronts would be more likely to impact further south over the UK with the GEFS scenario. But that's being a bit picky on the whole we are looking at generally settled and dry weather in a warm airstream, relatively speaking. Moving into the 10-15 time frame the main change possibly the weakening of the Atlantic trough (losing the negative anomaly) so less amplification but still positive anomalies adjacent to the UK. There is no total agreement on this pattern and everything is a tad nebulous so there is plenty of room for some adjustments over the next few days. Meanwhile things continue to look quite pleasant particularly for the southern half of the UK.

The Ecm 12z looks nice and settled following the unsettled blip, overnight frosts and fog patches will make it feel seasonal

Ecm backs up the potential imho. Remember the change occurs in January so beyond the Ecm range, but ecm at t240 shows the majority of the pv shifting over to the Russian side with the last remnant to the east of Greenland and losing its mojo. From there we should see the gfs majority trend to t360 to build Atlantic blocking.

Been hearing plenty of geese overhead this afternoon, far more than we normally do. Just had wild piglet vindaloo - should add a few knots to the old windspeed later...

We've already got some power cuts on Skye and one of my neighbours has recorded a gust of 89.9mph. Cannae wait for Big Babs tae arrive and sort oot these wee puffs o' wind we're gettin' the noo!

Forgive me for posting such a far FI chart Summer Sun but the 06z ends on another interesting note. Ridging towards Greenland and frigid air descending. Some 'happy endings' appearing at least make the output interesting. Needs to be taken with a fleet of gritter lorries of salt but it seems to me there are tentative, nascent signs of an interesting January.

Storm Barbara has been officially named by the Met Office for the low arriving to north of Scotland on Friday, the north bearing the worst of the winds, their yellow and amber warnings suggesting 60-70mph gusts widely across northern areas, 80-90mph across northern and western Scotland. Strong gusts along the cold front but strongest gusts reserved for far NW closer to tight gradient beneath SW side Barbara passing to the north, though GFS wind gusts don't look quite so severe as the warning suggests away from the far NW. Then hot on Barbara's heels, I guess it looks likely Xmas day's low maybe named Conor, which anything, looks worse than Barbara atm on GFS, with the low centre passing further south between Orkney and Shetlands

00z EC ensemble mean and normalized standard deviation chart for day 10 suggests good confidence (greens) in a ridge building N over UK. So looks like the days of Atlantic influence are numbered, but still a long way from getting some sustained cold and wintry weather.

Before any usual suspect beats me to it. Here is a 384h mean chart, I mean this proves conclusively we're stuck in zonal until the end of time does it not? Of course not, it isn't much use in the current discussion and I DOn't know of any real use for it but there it is, just in case anyone tries to trot it out in a meaningful manner.

Its looking increasingly likely that after the coming unsettled spell which is forecast by models charts etc Will come a spell of high pressure dominated weather for the UK but where this high pressure is going to be situated come the turn of the new year is still yet open to many possible out comes .of course it could move away south allowing the atlantic train to come rushing in ,or it could even back west then migrate north , there seems to be many options on the table , but looking across the atlantic it does look like high pressure could be setting up shop around n east canada ,which could allow our weather to perhaps take on more of a wintry outlook as high pressure could set up further to our north ,but i,m hoping that all of us can see some wintry weather come next year ,A bit of snow on the ground hanging around for a while and a few ice days ,not asking for much ,i can see the headlines now ,5CM snow causes chaos ,transport paralysed ,Net weather posters dragged away by men in white coats ,cheers gang

Heaven forbid you disagree with a ramper. CC is absolutely spot on with his assessment of that chart and the contradiction of Frosty's post. In the posted chart, there is still a large chunk of the PV over Greenland, and we are under a HP cell, but on the warm side of the jet. There is zero chance of cold in that chart at all, apart maybe from inversion. People jumping all over CC, because he disagreed with a ramper is just ridiculous. I'm an amateur too, but I can read charts, and CC was spot on.

I don't think anyone should write January off with perturbations like these from the GEFS 12z..admittedly they are in FI but they show potential all the same, enough to keep coldies interested!

The majority of the vortex is not on the Russian side at all. It's fairly central and directly over the pole. There is 0 of interest on that day 10 chart- a familiar tale of our HP not being able to gain enough latitude. All it's doing is stinking up the place time and again. That's exactly the same set up we've been in for weeks now with majority of jet going over the top of MLB.

Another quick one, and this is really just a community tool rather than something we'll widely be showing on the site. But if you want a quick comparison between the GFS and GFS para you can here (00 and 06 runs only) http://www.netweather.tv/index.cgi?action=gfscomp;sess=

Re polar vortex. This is the easiest piece I can find that is from a reputable site. http://scijinks.jpl.nasa.gov/polar-vortex/ thanks to NASA. Now look at the last operational and para from gfs as we enter January. I think it's clear that the pv is broken in the Atlantic as we enter January. We've seen the strato struggling so far this autumn winter with a disconnect.

From a purely selfish point of view this is my favourite chart of the day. Blizzards for the Alps with a frigid air mass straight from deepest Siberia to sweep the plains of Northern Europe. 1070 mb Greenland high ready to link up with UK high and to open the flood gates for super cold Arctic air to sweep through the British Isles. We can only dream, but its there ! As I said in the post above we have a blocked winter but we need to get it in the right place, plenty of time yet . C

Well based on Ian's update, it might be just me but I can think of worse places for HP to be than west of the U.K. This winter's not over by a long stretch, and there is bound to be some eyebrows raised (in terms of cold weather) over the next few weeks I'm sure.

Cook it and eat it now ! Which means I can have my sticky toffee pavlova And isthmus always reminds me of Violet Elizabeth Bott. Who had a listhp.

Cold is further west on this run. Ridging sharper and further north.

Storm Barbara may get renamed Storm Blowjob if she's gets a full head of steam up...

the tropo response was a big fat high pressure, not a pv endured low pressure. The tropo vortex is pretty dead.

Higher altitude charts eg 30hPa compared to 100hPa, will always show a 'strong flatter' vortex because the higher number tropospheric waves i.e shorter waves, are filtered out by critical level filtering, as their phase speeds match the background wind speeds. This is why really only wave-1 and wave-2 are considered for middle and upper strat. With regards to strat vortex strength and favourability for northern blocking, there is only a weak correlation with the upper levels of the strat and the troposphere particularly for our neck of the woods with the NAO. For example for Januaries since 1979 there are 5 strong +ve NAO daily values >2 - all had 10mb wind speeds >40m/s. There are 4 strong -ve NAO daily values <-2 - they too all had 10mb wind speeds > 40m/s.

Actually I wasn't trying to make a point except that the 06z anomaly supports previous runs and the EPS on the possible evolution. it is not in isolation and given the circumstances it's a reasonable percentage play. Certainly better than instinct.

No criticism of either you or knocker, but one thing this winter has shown so far is a disconnect between longer term forecasting and the resulting weather. At this range you both have a valid point and show signals both supporting and discounting such an outcome. But going back to the disconnect is it not possible we will have an unforeseen situation arise that goes against what some signals show. In a probabilistic sense we were meant to have a blocked "front loaded" (for cold) winter due to various supporting factors. The lower probability outcome has ended up prevailing due to other factors. Moving forward we could just as easily have a situation where a lower probability cold outcome could arise, potentially against some factors as Karyo has already put so well. It could be a winter of surprises in the timing of mild and cold outcomes. PS I do like seeing discussions like the two of you are having, improves everyone's knowledge

But it does rather support the anomalies

Interesting 06Z today: two potentially damaging storms in the short-term; in the middle-term, a few days' TM air with 850s of almost 10C, and, last but not least, the one that will never verify: the magic that frequents the T+384 time period! So, it's as you were: all to play for and more runs needed!

A quick point on using the mean 850 charts as a stand alone forecast tool. When there is a large spread, as there is on the 00z GEFS, using the mean average alone can actually skew what is a low confidence data set. loooking at the period from say 26-29th on the 00z we have a big spread in the ens, a cluster of members are actually trending colder, -5 to -10, while we also have those going milder up to + 5. That is quite a large spread and unless we see some tighter clustering using the mean alone is pointless. I also tend to think this important rule when looking at means in general, to often we get the mean chart anomalies posted and used as a forecast tool in isolation. The clustering of the individual members is what is most important, 5 mild vs 5 cold will give you a mean of average conditions whereas cold and mild are equally as likely and the average conditions are not actually forecast at all!!! The clusterings are the most important part of any ensemble forecast, without studying the individual members using the mean alone is futile.

There it is in all its glory now we just need to get it shown at 00hrs