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Just wanted to share a new feature we've been working on. It's the first mini update of a much wider set of new model and forecast viewers - this one being a global, interactive jet stream viewer. You can move the globe, zoom in and out etc etc. Hopefully it'll prove useful! http://www.netweather.tv/index.cgi?action=global-jetstream;sess=

I can't believe more people are not seeing the trends today. The lovely negative tilt to the "attempted" Atlantic assault coupled with the ridging into north west scandi. I would advise some on here to look at the charts from yesterday at the 6 to 7 day timeframe and compare them to today's 5 to 6. You will see what I mean. Remember those long draw south westerlies the models were showing in the medium range 48 to 72 hours ago? Where are they now? Get my drift?

This will almost certainly get deleted and fair enough, but just because there hasn't been a snowfest, this WINTER cannot be denigrated as a long autumn, unless you are volunteering to scrape the ice from my windscreen when its -8 deg C? In my location we've had more frosts than I can count, including several that have lasted all days in sheltered spots. We are clearly entering a period where the atlantic weather will edge a few hundred miles further east - it doesn't look like a return to classic zonality. With the SSW (or near SSW) in play it seems likely the the dice are being thrown and this may start to show in the later stages of the models fairly soon. And its not even Feb yet.

First nacreous clouds spotted near Tromsø, Norway. Very spectacular sunset here in Oslo yesterday, also due to the cold stratosphere (although I personally did not observe any "classic" pearly clouds). All signs that the vortex is indeed displaced. Picture source is the twitter account of Yr.no, a collaboration between the Meteorlogical Institute and state broadcast NRK. Edit: picture I took from the sunset here yesterday

So Matthew Hugo predicts half of Feb could be wet windy ,no sign of any cold ,right I, m off out of here ,the guy is very knowledgeable but we will have some very cold air to our far north driving this cyclonic wintry spell and if we get lucky we have a good chance of the white stuff ,right I, m back ,don't give up this cyclonic spell could bring us what we desire ,cheers gang .

Probably the booze speaking but I can see how MJO-driven amplification of the US pattern might cut off the feed of new lows into the trough in our vicinity, leaving it to slacken off with the jet meandering south and any residual shortwaves getting down into Europe a bit with fun and games on the north side... probs take until at least day 9 to come around though - if it does at all. If I keep scraping at the barrel...!

Whilst the outlook remains the same, it is to be noted that the extended eps trend is along the lines of the latter frames of the op whereby those lower heights drop further south into France and Iberia. That will always give rise to runners in the base of the trough which at this time of year, could deliver some of the white stuff to the south of the uk whilst the northern half sit under cooler uppers anyway and cool zonality always carries potential. let's see if tomorrow's suites follow suit.

I do . Honestly Nick the weather up here in Northern England has been beyond tedious for much of the past few weeks - chilly but not cold, hardly and wind, the odd frost but mainly a ubiquitous anti cyclonic gloom. I for one really like the look of the ECM and look forward to the sound of wind and rain lashing the windows.

Morning all A remarkable day yesterday - I've lived in East London for 13 years and this was only the fourth ice day I've recorded in that time. Indeed, as others have reported, the temperature actually fell slightly during the day as the chill wind intensified. It's the first ice day since March 11th 2013. This spell of cold weather which started on January 16th has been interesting. I know for those who only want snow it's been frustrating but for fans of cold it's been noteworthy. Five consecutive days of unbroken sunshine from Tuesday to Saturday is remarkable and a long series of consecutive night frosts (and harsh frosts even for London and with another sharp frost overnight). As is so often the case, these anticyclonic cold spells have left the best for last as the entrenched cold is intensified by a SE'ly flow from a frigid continent as the Atlantic approaches. We've had two or three spells of fog - last Sunday night's freezing fog was as thick and persistent as I have ever seen. Had we had a cover of snow, yesterday would have been even colder - possibly approaching 18th December 2010 but a long way from the remarkable January 12th 1987. I wouldn't be surprised to see some March snow in London - it's happened plenty of times in the past.

I've seen enough assumed very westerly spells get cut suddenly short to know that runs like the ECM are enough to bring the idea that the block will remain very close to our east into the frame. This doesn't promise cold conditions directly but does help with attacking the vortex from the Eurasian side and let's face it, we need all the help we can get!

216 hours of horror? A tad dramatic considering the different slant the ecm takes this evening.

I love the look of that evolution, I really do... It's only going one way, low pressure will undercut the high and drag continental air westward. Problem is, I don't believe the evolution!

Yes, looks like the high is going to be more resilient on the next few runs. Could again hold up zonal thrust . Very similar from UKMO at 96 hours. The Sunday rain extent northwards is still not determined , could be delayed or move further south.. The main Atlantic jet on APERGE is diving well south at 106t. Have a feeling the robust nature of the block is going to cause some problems to the models this weekend. C

The APERGE remains fairly blocked at 114 hrs - it's rather on it's own at the moment.

If it's cold & meaningful snow you've been after then you could say this winter has been over for some time. I'm actually looking towards spring now.

Well there are things happening in the strat, so I'm not as convinced things are going to be as relentless as they seem at the minute. Surely not long before we see more favourable output once the models pick up on the signal?

Well for me. Winter is over. No doubt we will get a cold Spring though.

I'm still positive for our prospects for the rest of winter regarding possible snow and decent cold. I've always considered March to be a winter month particularly here in the south east when we tend to get a raw easterly wind. Onwards and upwards

The GEM keeps it blocked too with high pressure building over Svalbard.

UK Outlook for Saturday 11 Feb 2017 to Saturday 25 Feb 2017: At the start of this period the most likely scenario is for more unsettled weather with wet and windy spells interspersed with brighter, colder and showery interludes. There is a risk of gales at times, particularly in the west, where the heaviest rainfall is also most likely. Temperatures are expected to be slightly above normal for the time of year for most, although with colder interludes more frequent across Scotland and Northern Ireland. During the second half of February there are signs of a more prolonged colder spell developing, but confidence remains low in the likelihood and details of this development. http://www.metoffice.gov.uk/public/weather/forecast

Agreed - just as an example, I'll include the SSW reanalysis charts for 2006 that I posted in the winter thread. pre 2006 SSW - almost identical to the current displacement. Afterwards the vortex moved over the Eurasian land mass and led to a colder pattern for the UK. This is the type of response Cohen is looking for in his recent report and what @Singularity was describing, either here or in the model thread. I'm not seeing that yet as the tendency this time is to want to move back polewards after each wave of warming. The QBO was east phase back in 2006 - the fact we are in a strongly west phase may be what is preventing the final push. Looking at the temperature chart does not help here - need to look at the geopotential heights charts that go with it. http://www.instantweathermaps.com/GFS-php/strat.php

The outlook is horrendous, rain on nearly every day. What is there to like about that? Give me 'cold nothingness' any day.

Morning all After yesterday's remarkable ice day in the SE, a significant change is imminent with a return to Atlantic-dominated weather. Too early to get an exact feel for storm tracks and intensities but the general view from the models is of a succession of vigorous depressions moving SW - NE up the west of the British Isles with copious amounts of rain and wind especially the further west you are. The secondary features could be the real problem as one or two of them deepen explosively in the flow. The Jet is strong and over or just to the south of the British Isles so all areas will see some wind and rain and the latter won't be wholly unwelcome after an extraordinarily dry winter. We're in this for at least 14 days in my view - I do think the upcoming warming and further activity will weaken the stratospheric vortex - the 10HPA temperature rises from below -80c now to -60c in a fortnight so that for me is an indication of a weakened PV which may be vulnerable to further and more advantageous displacement. The GEFS members are starting to sniff some options at the furthest edge of FI with both Greenland and Scandinavian blocking options from one or more of the members though it has to be said the majority keep the Atlantic flow. Going beyond mid-February I still see plenty of opportunity but as always we need a fair bit of luck and the cards to fall right. The models aren't going to make pretty viewing (unless you like stormy conditions) for the next week or so - by then, I think we will start seeing some eye candy in FI and the chase can begin in. After 10 days of cold, I won't mind some warmer weather.

The question is how long will the westerly pattern last? The Euro high lingering has meant what would probably have been a short and sharp zonal period now likely to last over 10 days due to the trop PV lobe being corralled to NE Canada with the aid of the Pacific ridge. The winter modus operandi is for any zonal period to be fleeting so just bad luck on this occasion that at the height of winter we have a persistent block to our east preventing a reset of the PV and giving little chance of any snowy outcomes. The D16 mean does suggest a leakage of the strat PV from the Canadian area, but even at that range it would still mean a wet and windy with above average temps as a whole for the UK: Looking at the gEfS and there does not appear to be any consistent signal for a trop wave from either the Azores or Pacific and although the PV appears primed to be smashed up there is just no sign of any MJO forcing yet. The MJO has been a bit player this winter just when we needed it to be the star of the show. We know the models are very good when a zonal period is forecast, so the upcoming long wave pattern is probably a done deal. The next week modelling should give us a guide to how the trop NH profile will develop once the blocking has dissipated and the PV can spread over the polar regions freely. Unless we get some help from the strat, getting any HLBs look a long shot (based on this winter's poor efforts) so we will be hoping short wave developments will bring us transient shots of cold. No clear signal from the GEFS yet.

I am a bit more encouraged by the 12z EPS z500 mean this evening, with a ridge west from Scandi toward Greenland at day 10 and it's still there and still prominent days 11-15 too. Which could indicate tentative signs that the displaced sPV may be altering the height fields to our N/NE with time, though the displacement is initially responsible for ramping up the Atlantic for at least a week and probably more, though at the same time shifting the jet south. More runs needed for a trend, but the ridging to the NE, although too far away to keep the Atlantic at bay form us, will help create wave propagation up towards the strat, perhaps an increase in wave 2 activity.

I'm actually as optimistic as ive been since the failure of early December, the strat PV does look to move back over the pole in GFS FI and that will probably verify, but the models (particularly ECM) looks to still attack from the SPV both sectors, even if those sharp ridges from Scandinavia into the pole are brief, as log as the Russian high stays there or there abouts and the atlantic troughs are sent on a Southerly track, I can see a late feb SSW (classic precursor pattern), I know March lessens the chances of potent cold and snow settling in southern England but it can happen, the Strat PV looks weak and looks to me like its ripe for attacks from below and set to weaken and vulnerable to complete destruction from another over the top SSW (hopefully Tamara will give us good news from the Mountain torque charts in in a couple of weeks, I heard from others about MJO phase 6, if that can continue into 7/8 and amplify in 8 (which ties in with timing of likely fall of strat vortex and something looks to be driving a signal on GLOSEA as met are now going for a cold spell with low confidence in about a month, I would risk a bit higher and suggest medium confidence, the most confident ive been all winter anyway, another problem like I said, timing uncertain and people in southern England might be looking forward to spring by March but to e there looks like a seriously deep trough to the South East is well within the range of long range solutions, and that would be likely to deliver something potent. Don't panic if we don't start seeing any belting FI ensembles for another week or so.

I'm looking forward to summer now, for me winter is over. on to winter 2017/18 fromey

Well another glorious winters day started at -1c and rose to 4c. Ground frosted hard in the morning with the freezing wind and now the surface is very dusty. Second day of young Mr. Northernlights taking off stones in conditions better than many March/April days .At least they"ll be off before the snow comes in March/April.

here it is again - really easy to visualise on this what's going on at 10 hPa, especially if you click on a point and get the spot temp. warmest I could find was -8.9 against -80 at coldest. https://earth.nullschool.net/#current/wind/isobaric/10hPa/overlay=temp/orthographic=-13.19,93.29,255/loc=69.726,57.984 fascinating stuff

Do we really need updates to tell us there's no update?

Yes,you are so right! All the high pressure that everyone was banging on about wanting just gave us cold nothingness,down here at any rate. Folk should be careful what they wish for.At least we have some proper weather on the way now.An end to this boring stuff thats seems to have gone on for ever.Plenty more types of weather to enjoy apart from snow,this is a weather enthusiasts forum after all? Regarding the models,as some other poster said,if the met/beeb dont mention it in their 5/10 day forecast then it aint happening. As for the obsession with easterlies I just dont get it. If its snow we're after tben theres huge swathes of Uk and Ireland that dont really benefit at all from an easterly,only the east coasts of both islands are guaranteed ought,even down here in south east its not certain,though you cant beat a thames streamer when it gets going! Pm winds are generally much more giving to more areas. And for all those who bemoan the end of winter as we knew it,take some time out and read the historical monthly summaries on the metoffice website.Think its in Climate section.They go way back! Things have changed little.Plenty of boring snowless winters then too.There were some exceptionally prolonged cold snowy spells in the past,and there will be again in the future!

Can someone clever help me here. Sometimes I get the feeling in this strat thread that it's all or nothing. I.E. If we get a reversal of -1m/s, we could get a huge hemispherical change. But if the 10hpa 60N zonal wind stays just above e.g. +1m/s, nothing will get achieved. That's just the way it comes across sometimes. Is that really black and white like that? Or are the consequences more proportional in line with the speed? (In which case, who would be bothered whether the wind speed is +1 or -1?)

The lowest was -3.7c which, considering the winter we have had in this area, has been the lowest overnight since November. Currently sitting at -2.6c with a hard frost.

J. Cohen has this to say about the upcoming/ongoing Strat event and his expected impacts; https://www.aer.com/science-research/climate-weather/arctic-oscillation of the impacts over Europe he says; "Finally my thinking for why Europe could turn colder longer term is because of the possibility of the stratospheric PV being displaced towards Europe. In my opinion this scenario increases in likelihood if there are multiple WAFz/poleward heat transport pulses. If the stratospheric PV is displaced bodily into western Eurasia this would likely setup easterly flow across Northern Europe in the stratosphere followed by potentially the same in the troposphere. But even if the stratospheric PV is not displaced into Europe but close to Europe, the flow around the PV across Europe will turn northerly in the stratosphere and could eventually turn northerly in the troposphere across Europe as well. Either a northerly or easterly flow across Europe would transport colder air into the region. This scenario is not predicted as the short-term response to the SSW/weak PV event but could be a lagged response starting sometime in February."

An absolutely baltic.............................. -0.5C - although I had my own private battle with windscreen frost earlier... first world problems eh?

I thought at the time that QBO anomaly happening a good few months back could be the one thing that scuppers a cold winter, people said it wasn't important but there was a chart with solar / qbo combinations somewhere on last years thread and it does reduce the chances, the other thing I overlooked with my early thoughts on winter, is that although we have low solar activity, it is not technically a solar minimum, Not sure if theres a lag effect with that as I don't really know anything about solar activity but I get the feeling if we had hit solar minimum and that QBO would have been East, coupled with the fact that regardless of those 2 factors we have still been close with some MLB blocks - ( 'the nearly pattern', ), then we would have been looking at a fairly spectacular and protracted winter.

Its more important where the Ridge / vortex or vortices position themselves after the warming, On that 192 chart, if there wasn't another warming immanent, the vortex would quickly move back over the pole, I'm guessing here but probably with negligible effect on the troposphere.

I thinks its just terminology to be honest +1/-1doesnt really make any difference to the Strat pattern as a whole Strat zonal winds are marginally slower in today's update, also the additional warming signal is still there.

A hard frost overnight. Currently still sat at the overnight minimum of -5.7C/-8C. Good to see a blip of decent cauld weather after one of the blandest (and driest) winters I can remember. I know there's still February and for us kilters, March to go as well, but it's hard to see anything notable rescuing what has been a very disappointing winter from this cauldie's p.o.v. To the weathergods: would really prefer a cauld and snawy February to another cold, wet spring.

-3 this morning and a requirement to scrape the car. Happier than a pig in .....

Not surprising there isn't much comment when this is the forecast: You can either have windy with rain on the UKMO run, or very windy with rain on the GFS run. From a couple of days back, you can see now that the rainfall is progged to still be heavier in the west vs the east, but totals starting to mount up in the 6 day period, with more to come after. Looking a bit further ahead, and above, and things ain't pretty:

Cheers Nick,not looked at the anomolies etc just yet as i have not been in long(afters eh!) but the atlantic has been held back again has it not!,last week the charts was showing the atlantic barreling through come this monday just gone and we have an ice day today for some,it just goes to show how much the weather chages in a week to what the models show prior.

Can't be bothered to post all of them, but here's weeks 1-4, not exactly pretty ...

There's no ignoring the deep trough signal extending from the mid-Atlantic across to the UK, but at the same time, the jet will be tracking south of usual and with that configuration there will always be a chance that one of the potential intense lows doesn't find a sweet spot and remains as a shallow secondary low that could make a run south of the UK with a bit of luck. Okay, a lot of luck From the latest guidance it'll take until about a week into February for the MJO to start providing some useful ammunition with which to reconfigure the pattern to something more pleasing to those not happy with stormy weather and highly variable temperatures (I'm actually quite alright with a bit of that down this way, as long as it doesn't go on for too long). At that time it'll either be battling a vortex returning to the pole, an unhelpfully displaced vortex or, in the by far most desirable scenario, a vortex that has been knocked right of its feet and displaced bodily into western Eurasia as a result of a secondary wave of warming that starts around day 10 and which ECM seems particularly keen on - much more so than GFS. Chances are the MJO gets there ahead of any vortex knock-out so there could be a(nother) difficult period of model watching in early Feb as the models struggle to resolve a more finely balanced situation. None of this is at all certain though, what with model MJO projections having proved unusually dodgy at times so far this season. Yet I continue to focus on it as a key driver because it's integral to adjusting the global atmospheric angular momentum budget in favourable ways for wintry weather in our part of the hemisphere, as Tamara has kindly been reminding us from time to time. Other key components include mountain torque events for example, but I'm less well practiced at spotting these in advance. I can be said though that this is the best picture painted by ECMF and UKME (based on extrapolation) this season so far. GEFS is a bit quick to leave the W Pacific behind to be what we really want, despite how good phase 7-8 transitions can be in Feb. CANM paints an undesirable version of events that, as much as I want to, I can't go ahead and discount due to the usual slew of caveats. Right, that's the net of hope cast out yet again in 'the winter of the dangling carrot' or whatever you might wish to call it. Jan has essentially been a very near miss - those epic model runs at the turn of the year showed us what ended up romping across pretty much the whole of Southern Europe and has only now decided to come roaring at us, from the southeast, as the brunt of it makes its (long-awaited by S. European residents) departure. We got to experience a single day with some of the conditions that we could well have had for a fortnight or longer. A small mercy, I say!

Yes apparently cycle 25 could be even less active than our current cycle. Just need a series of large volcanic eruptions to really bring us another mini ice age!

Made this video 7 years ago, Winters 2009 and 2010 revisited:

Since 1948 there are 11 Autumns with average 30mb QBO < -20 and they are followed by winter CET average of 4.58°C The remaining 57 Autumns were followed by winter CET average of 4.29°C The winters were (with DJF CET values) - 2005 4.4 4.3 3.7 2007 4.9 6.6 5.4 2014 5.2 4.4 4.0 2012 4.8 3.5 3.2 1974 8.1 6.8 4.4 1979 5.8 2.3 5.7 1996 2.9 2.5 6.7 1970 4.3 4.5 4.5 1972 5.8 4.5 4.3 2003 4.8 5.2 5.4 1984 5.2 0.8 2.1 The interaction between QBO and stratosphere vortex is not as simple as horizontal wind shear or momentum flux. For example, in the paper Interannual Changes of Stratospheric Temperature and Ozone: Forcing by Anomalous Wave Driving and the QBO (Salby 2011) http://journals.ametsoc.org/doi/pdf/10.1175/2011JAS3671.1 a comparison of modeling and observation shows that The explanation is quite complicated but described clearly - TL;DR - looking at monthly correlations between QBO and 10mb wind, the strongest correlation for December is actually with previous June (0.45), January with previous September (0.43) and February with previous December (0.32). For winter 500mb 60°N zonal wind (or surface), there is no correlation. Wave driving is the major factor controlling the vortex ahead of QBO which affects how the wave driving behaves rather than direct momentum transfer, with vulcanicity, ENSO and solar very much in the background. edit: forgot about dodgy values giving no proper QBO signal in the early years - why they bother including them is a mystery. No matter, excluding the first 7 years so starting in 1955, takes the QBO > -20 years winter CET from 4.29 to 4.30.

You can't really make a universal comment from a single location. Has happened before, there have been occasions when the south of the UK has been colder than the north. Happened in January 1964, the winter of 1962-63 was colder in the south than in the north. The south have had a more continental influence, with flows from south and east this January.