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  1. 46 likes
    Evening All- Today is probably the first day that many will start to take notice of the ECM ( & of course the UKMO which dovetails nicely in together at 144 ) What we have here is a clear case of a model backing away from the initial proposed continuation of the zonal flow to something potentially very amplified. This transition is clearly demonstrated in the modality change of the AO taken from the 12z ECM operational. It has to be said & earmarked at this very early stage that no-one can be certain of any outcome whether that be some deep seated easterly or a flattening of the pattern with no cold. The ECM ( & GEM ) are picking up a transition signal & at day 9/10 may well continue to move fully through that transition to a scenario of what want ( a la 2013 ) or indeed stop short of Nirvana. Whilst he was ridiculed on here for all the right reasons certainly the Ian brown phrase of if you cant see the train then its not coming- Its great to see positive developments over the last 24 hours at 8/9/10 whilst the interim continues to show periodic snow events at localised levels over the UK... An exciting few days to look forward to - All aboard the chase as it starts inline with the crimbo run in......
  2. 41 likes
    I am sure that many many on here, and I absolutely include myself in that, do indeed get a buzz from seeing cold charts in the forecasts. No matter how far away. GFS +384, ECM +240, teleconnections, ensembles etc. Us watching for trends, patterns, signals, Trying to second guess cause and effect of every minute change in the atmosphere from run to run. All in a massive 3d world from the top of the stratosphere to the pavements outside our houses. That is all part and parcel of this mad annual winter ritual of ours. Personally, I would just find it incredibly boring if all the charts only went up to 3 or 5 days Most here are plenty long enough in the tooth to know that those faraway charts eye candy charts have many hoops to jump and many hurdles to clear before making it into the more reliable time frame (and even then will most probably go wrong).. But if it ties in with the 'background signals' (no matter how tentatively sometimes ), then yes, absolutely, that's what it's all about! I see no reason why good cheer, hope and optimism should be curtailed in those instances. In the same way nor should the perennial pessimists and pragmitists amongst us, who arrive like clockwork to pour hot water on those hopes and dreams (as long as not trolling of course). Each to their own in life, but for me it's always been all about the chase...
  3. 38 likes
    And this is why I'm reluctant to post in this thread. I was in no way trying to 'shoot down' anyone but merely politely trying to point out why this is misleading. It is a shame if one cannot do that. And for the record I do not put myself up as one of the more knowledgeable people on this thread, unlike quite a few others.
  4. 38 likes
    I must be the only one then that looks at these chart and walks off satisfied. Anyone hunting wall to wall snow in November needs to read their history. The pressure differential between Greenland and Scandy on those charts is pretty good for vortex disruption when combined with the Aleutian low in the North Pacific. November is nothing but a setup month - no low ground product in terms of snow is realistic. In addition the pattern is effectively blocked, and people need to realise that a block creates a more meridional flow that promotes warm flows from the south as well as cold flows from the north. The fact that the Scandy anomaly helps pull warm air up over the UK is part of life in this part of the world at this time of the year. The pattern is not one of raging zonality, the strat/trop disconnect remains in place at least for now, and vortex stress looks likely. Winter doesn’t start for 3 more weeks, and realistically doesn’t really kick in until mid December which is 5 more weeks. If you need to cheer yourself up in the search for snow try reading up about the Feb 18 reversal that led to that beastly spell. The Atlantic preconditions are not dissimilar and while every patten is unique we are certainly in with a chance of a cold outbreak this season. Just don’t expect it in November and don’t expect it to last all winter. 1963 was unique and a year I don’t think we will see repeated for as long as the world continues to warm.
  5. 37 likes
    Would that be this winter, only 8 days old, with another 82 days to go? Which has already delivered a lovely cold start to December with widespread frosts for many, and an Atlantic storm now in the western approaches? Some have been reporting hail and thunder in the south west today as well. Goodness me, hasn't this been a promising start to the season? No reason to lose heart so soon, my friend, just because we're not all buried in snow - yet. Every year I see the best winter weather conditions develop almost overnight from nothing in the 5-7 day period so we should all keep looking because the next great blizzard may only be just around the corner!
  6. 34 likes
    So Ensemble watch getting exciting now as I have introduced the 'deep cold' circle today ( sub -7c ) & that is tracking SSW with each run....
  7. 34 likes
    I cannot believe the total memory loss of the same old people here, thats the same ones posting the same replies as they do every year - defending the GFS when its going to be wrong. When you have UKMO aligned to ECM & ECM mean at 120 they are NEVER trumped by an out of kilter GFS especially the 06z which is like comparing a pedigree with a stray. So for all the neutrals who wonder if its just opinion or is it sound education over a few years lets take yesterday as a prime example of how bad the 06Z GFS is - UKMO 144 yest V 120 Today That is a superb match across day 6 down to Day 5. Metronomic consistency with minimal adjustments all around the Globe. Now look at the runt of the litter the GFS. Same timeline. Yesterday at 144 No Greenland High, No decent arc of Cold coming through Scandi UK in southerlies -- Look how much this model has changed in that short time span... * So if yesterday was awful at 144 with no clue of the pattern then the probability is todays 144>168 is the same bin fodder How anyone who indicates they follow the models can put any credibility on such a pants model (06z) - means to me they are deliberate in their attempts to derail the thread. Back to the original well proven point * If the 06z goes off on a tangent through 144 then scrap it *
  8. 31 likes
    A surfer missing in Sussex has been found alive. Great. Now they can send the moron a bill for the callout for his stupidity.
  9. 30 likes
    ECM 192 has all the hallmarks of a weak stationary jet which is about to amplify! Its all backing up!
  10. 28 likes
    Caught some lovely structure last night. Just South of Hailsham, E Sussex, looking toward the coast.
  11. 26 likes
    Well if that's what everyone wants here I don't see a lot of point in anyone who finds this totally boring and pointless posting in this thread. I personally find day to day meteorology interesting enough
  12. 26 likes
    Good to see things ticking along nicely WRT pressure rising to the North & the atlantic systems being ushered on a more southerly track- Some may remember me commenting 2 days ago on the GFS being to far NE with its angle Well now look V the 2 charts from the other day Original prognosis at 84 was all the enery moving NE Now the same timestamp this eve on the 18z Note the swift change to the jet alligning SE This will stop the low ploughing NE through the UK which would have blocked the small ridge of high pressure moving NW towards Iceland- Now this ridge looks like developing so the return to colder runs has returned At this point in the year im glad the main thrust of cold is still 8-10 days away as for us down south thats really the earliest window we could really hope for snow anyway.... First Air frost here last night @ -0.5c Cheers
  13. 26 likes
    @Allseasons-si A classic 3 wave pattern. Anyway I think the key watch here over the next 14 days appears to be the amount of 'undercutting' we get from a high that aligns NW up towards Greenland... Very very interesting times - Early snow potential available for the North...
  14. 26 likes
    Evening All- 2019/ 20 Winter is over ! On the back of a record breaking persistent -NAO. So to add some commentary of where we are & indeed where we may end up I have cherry picked out some of the images floating around twitter this last week. The information > Route GLOSEA5 & GFS mid term modelling circa 50-60 days will probably run different parameters to the ECM seasonal however the images that are being used ( as I have over the last month or so ) show the atmosphere top down & how the strat may (or may not ) couple with the troposphere - Whilst these are a 2D image you looking at anomalies that depict the entire polar field where blue is negative heights & red is positive heights. As of today here is the progressive last 4 Months - & the whole year Of note here is of course no cold downwelling & residual warmth remaining in the troposphere linked in with AO - Since that 27 Sept to the updated chart of 07 Oct covering 10 days - Whilst the Stratospheric vortex has ramped up about 7 M/S its not filtering down - However the models *are* forecasting a Strat / Trop coupling in about 3-4 weeks ( This is what @CreweCold is always referring to when he says there no point in getting excited about Oct & even early Nov patterns if the blocking is going to be swpet away- Well we have that sort of transition occurring for the start of Nov- Both the GFS polar cap ( source AER ) & GLOSEA 5 ( source Met office ) show cold downwelling Longer range The Glosea model shows November polar field becoming very positive & that ongoing negative height remaining in situ > The classic positive December AO. ( Remember this models has been fed with Strat data as well NINO / QBO data etc ) So it would appear its going to go pete Tong... Or is it? Important to factor in for the next 6 weeks to observe. * The consistency & accuracy of the GLOSEA model at day 50-60 becomes very low meaning that the initial coupling prediction doesn't preclude persistent cold, indeed if we add the next days run for October 6th ( taken from the same source ) all of a sudden the persistent cold strat has been replaced by warming similar to 2009 Heres 2009 Last solar Min which produced a November warming - & we know how that winter went after that... & for reference here is the Crewe Cold worst case scenario +AO So the next 4-6 weeks will already tell us when we get to second week of Nov where the polar cap will be in terms of overall heights & the predicted modality of the AO for H1 of Winter. ( not withstanding the potential of a later SSW ) - The wild card the NAO. The NAO is usually a couplet of the AO / NAO phase where for winter one follows the other - however in isolation this summer & early autumn the NAO has often run out of sync by staying Negative even though the AO has trended neutral - Late september is a good example. we saw when there was neutral polar heights we had a peak pulse of -NAO, can we sustain this with a fairly supporting tripole all the way through coupling in November ...? Maybe ! Just a footnote new research suggests the SAI wont have the ability to drive the phase of the AO in winter ( especially early ) but rather reinforce a negative one later in winter if the base state was negative in the first place. So there you have it > No ramps & no claims this will be an amazingly cold winter - Just some markers set out ( week 2 & 3 of November ) to flag up what the prospects will be.... Best S
  15. 25 likes
    Once again some great and insightful posts, sorry about running out of likes! The 12z ensembles to me look just fab, the mean has come down further, and we are now looking at a fair amount of sub zero runs, I've even noticed a few potential snow makers on a couple of em. It's blatantly obvious things are shaping up well at the moment due to the increase in posts. This could be one hell of a busy run up to Xmas and beyond. 2010 repeat!! Let's go one better and have a 47/63 combined effort.... Could we cope with that! I'd like to think so.
  16. 25 likes
    Just as a very brief addition (before properly retiring to the sidlelines until next Spring) to the previous post made about 5 weeks back which alluded to the escalation of confirmation bias wrt weather preferences which.rises to its highest levels in autumn and winter Its based on a conversation I have had with someone who is a very well respected observer elsewhere, with a level of knowledge and perception that many would aspire to and of a higher technical level for sure than my own. Most importantly they suspend their own natural preferences and make judgements neutrally and based on the merits of all variables present and not selectively. Such observers I think are the ones particularly worth listening to and trying to learn from. Anyway, relevant to the here and now situation but extrapolating that forward in terms of future possibilities - here is some of that conversation based on my own contributions. A few further additions have subsequently been made to make it most relevant to the UK and Europe Yes for my own purposes, a defacto traditional Nina regime looks increasingly likely to persist in the months ahead. The question being where any Pacific convergence may set up to interfere with the regime and create scope for less tropical and extra tropical disconnect to the base state. In that sense the much less disconnected SOI plays a bit part if any westerly wind compartment is isolated, so to speak, due to a wider overriding -ve momentum inertia High amplitude Phase 3 GWO could well be set to return to Phase 1 as trade winds increase across the IO following the recent extra tropical increase in momentum. Once the +EAMT wavelength fades over coming days, -ve FT in the tropics will lead MT momentum trending -ve once more and maintain the GWO well within the Nina attractor phases - providing the steer to persisting sub tropical ridging. This sub tropical ridging is well in evidence in present modelling and amplification of this ridging during autumn and indeed winter to provide short lived colder incursions is quite consistent with many similar years and not at all unusual, or any signal of a harsh winter, This, plus question marks wrt QBO transition needs to be balanced against any weakness within the polar field c/o arctic and other destabilizing factors and why I personally continue to be much more ambivalent and sceptical about the relevance of blocking patterns at this stage of autumn in terms of what it might imply ahead. Just my view of course - and which customarily tries to be detached from mainstream hype that grows each and every year, at this time of year - and when sensible weather preferences and ideals often attempt to fit too many drivers to produce that desired outcome, when probabilities often suggest alternative solutions that are much less popular to the masses. The gist of this extract is that much is yet to become clearer in terms of seasonal overview, but especially stressing that model output commentary during the early stages of the short seasons and making assumptions based on persistence of certain aspects of patterns is fraught with error when attempting to assign specially selected drivers as a means to fit the desired outcome. To all those following progress of the weather patterns in the weeks ahead, try to enjoy progress and evolution - regardless of outcomes vs preferred outcomes
  17. 24 likes
    Goodmorning peeps Hope everyone is ok and a happy Wednesday to you all. A gloomy morning in Walthamstow nothing that resembles like a mid winters day it actually does not feel drastically cold. So here we are it's 22nd January today and no doubt most of us coldies are exhausted now having eagerly waited since or before the start of winter for some decent cold and snow. The eerie silence in here tells the whole story and deep down we all know that our time for this season is getting closer and closer to saying goodbye to this winter. Alas it was not probably meant to be this year, as a lot of posters have already said a lot of outside factors have just made us very unlucky. We have still got February left but deep down I know a lot of you like me have got that feeling that the hope of seeing something decent and snowey is fading day by day. The days are already getting longer and soon the sun will be gaining more strength. There is no sign in the output to suggest we are going to get out of this misery pattern soon. Having said this patterns have changed quickly and suddenly and who knows something dramatic may happen as we enter the last half of winter, but we would I think now need a dramatic event to turn things around. i have actually blocked the rest of this winter out of my mind now, as life goes on and dwelling on something that was not meant to be will not change it. Maybe in another 8 months the factors for next winter will look more promising. Not to add more gloom but chins up peeps as I said who knows February may have a final sting but if not then there is always next winter to look forward to. Hope you all have a great day regards
  18. 24 likes
    I will take the GEM control run please for xmas day ! Nice to see Matt Hugo copying me on Twitter
  19. 24 likes
    Plus its the NH..... UKMO will forever outperform the GFS in Europe > Another example today with ECM / UKMO identical at 120 V the random GFS. Anyone putting GFS above UKMO for Europe has been wearing horses blinkers for years. Next we will be rating the 06z GFS .....
  20. 24 likes
    The usual (probably quite dull by now) advice from me We should not be too quick to dismiss a single deterministic run, even if it is out of kilter with its own suite (caveat: I have not yet seen the EPS suite), particularly given the higher resolution of the deterministic run in trying to resolve some delicate balances over the atlantic. We simply don’t know at this stage where to judge this run and will need to wait for further runs. My second and definitely tiresome piece of advice is to be very cautious when looking beyond day 5 in the Greenland locale and particularly with regards to any suggestion of increased heights (those lovely greens and yellows on the H500 charts) - we have seen season after season a bias towards increasing heights too much in this area beyond day 5, only for this to correct itself the closer to T+0 we get. At some point, like a stopped clock, the models will sniff out one of these Greenland height rises correctly (and I do fancy that to be this year incidentally), but for now I would urge caution before we drive ourselves towards an early season meltdown. With Brexit coming Nick might struggle to get the Prozac over the border.
  21. 24 likes
    First I wasn't presenting a seasonal forecast ( just a paraphrased post) and am not a competitive forecaster anyway, and don't subscribe to competitive 'methods' either. If you read the post properly (which you didn't) then you would see that I illustrated this by saying that I don't have the technical where-with-all of the person (person(s) to which I referred. Being honest isn't a weakness and doesn't need to be compensated by tub-thumping statements that proclaim what the 'talk of the weather community is these days'... This is an an internet site for people of all levels and hopefully of managed ego's - , not a platform for parading 'method manifestos'. There is too much of this grandstanding in our outside world as it is... Arctic amplification was mentioned - I referred to it briefly as part of a condensed post and simply didn't write extensively about something that is pertinent to what you want to be the peoples anthem for the coming winter. It is one factor of many, which on its own does not lead to one favoured outcome all the time (as one season to another each year bears out), but involves consideration of multi-variables that might imply more than the one solution than a majority might want to hear. You are free to do this of course, if you want to steer towards a populist outcome - but things don't always work out in reality however convincing they might appear to those who like what they hear. Indeed things don't always work out for anyone when based on attempted objective discussion - the weather makes mugs of all of us. But better to start from a baseline that manages expectation and hopes to learn from mistakes rather than be a tribal lead to populist weather preferences . The price of narcissism does have limits
  22. 24 likes
    In my lifetime so far...today has been the equal greatest weather day of all time! (BFTE 2018 the other ) It had everything - warmth, sun, mist, fog, spectacular lightning, ear splitting thunder and a perfect sunset to end the day! If Summer finished tomorrow I would give it a 10 out of 10 after the last incredible four days! I would also be happy with something like this from the GFS 12z for the rest of Summer - if no proper hot weather was on the cards! Hope everyone enjoyed the scorching temperatures down South today - shame we didn’t break the record but we have all learned so much about upper 850’s, surface temperatures and North Sea wind! A big thank you again to every single member who has posted in this thread and previous ones - it has been a joy to read! We go again in July!
  23. 24 likes
    Aside from the daily commentary of updated model suites, from a regular few and which proves a useful, helpful and pleasant antidote to mood swings, unfortunately far too much typically absurd and unwarranted overreaction to the inherent erraticism of numerical modelling is omnipresent as usual on here from the usual suspects - and which serves no useful or rational purpose at all. This, much more of a nuisance than what NWP (apparently) most lately suggests itself So, by way of most recent example of this - we arrive at the point that sections of NWP, about a week back (including long term EC monthly!) was mapping out a good 10 to 15 days at least of cool and changeable weather with a trough anchored very close over and to our NE, phasing with further disturbances arriving across the Atlantic on a supressed jet stream. Instead we look at this to end the coming week and the weekend Its not, and was never likely in my opinion to be a long term sustainable ridge - but what it does do is represent a likely recurring pattern in the opening weeks of summer based on the detailed discussion of parameters discussed in the previous post, and many preceding it. As suggested in that post, this is not likely to be another 2018 type summer with weeks of blazing anticyclonic ridges and so expectations should be adjusted accordingly in my opinion. If not that, then at the very least learn not to flinch with each and every output, or better still, wait a period and see what emerges over a period of a day or two rather than every 6 to 12 hours! On the basis of a diagnostic, rather than purely wholly numerical modelling approach - for the opening period of summer (at least) it does look to me to be one punctuated by an Atlantic trough and downstream ridge pattern that breaks down and then re-programmes. Rinse and repeat. In that sense, the above snapshot of the expected weather pattern to end the week (and very pleasant conditions) conforms quite closely with those prior expectations. And its not a bad place at all to be at the very start of summer - irrespective of whatever else is currently suggested to follow. Looking ahead from this time, personally I am very sceptical of any NWP trying to break down the weekend pattern sustainably by, yet again, suggesting a repetition of a week or so back with a same extrapolation of breakdown into equally sustainably cool and changeable conditions in the extended period. Operational NWP shouldn't be taken at face value at any time, and that includes ensemble data at long range as well - which is equally quite prone to change direction like a shoal of fish in midstream, when they exert a bias signal and appear unable to "see" beyond the that signal to the next. After all, it gets forgotten on this thread by some - but its not the computer models that drive the signals....but its... So NWP in the last 10 days or so has been particularly poor, and is likely to continue to be unreliable which means that human reaction to every output should be adjusted accordingly. This also means that whilst upper air noaa anomalies do represent a best guide as an overview of NWP - they too still remain just a snapshot in time and will also change as computer models evolve with signals. So a good idea to adopt a cautionary word here also at not taking them too much at face value. Relative global atmospheric angular momentum remains comfortably above average and with a fair degree of westerly wind inertia in the atmosphere and more to be added as another MJO wave begins its course through the Indian Ocean to arrive in the Pacific later in June.. This to help programme further downstream amplification in this sector of the NH heading through the month. AAM forecasts continue as before to advertise this supported trend. Whilst the natural interim supressed phase of convection over the Pacific (shaded orange) temporarily creates some upstream amplification and a little extra downstream polar jet energy, -as cautioned above, the risk of overreaction to this shorter term signal is clear and questions any attempts by NWP to try to effectively "crash "AAM and as a synoptic response send sustained increases in polar jet energy over the top of a retracted and amplified Atlantic ridge such as the ECM operational is currently trying to do. As long as the tropical signal resides as default in the Pacific, and angular momentum therefore remains sufficiently buoyant, then an upstream ridge and UK trough remains counter intuitive on any holding basis. . Look at where the low frequency tropical signal resides close to and just west of the dateline in the Pacific It supports an El Nino type standing wave, even if not a "pure" basin type El Nino. In fact, the standing wave due west of the dateline is better than any east based signature which would supply too much of a southern stream (as unhelpful for warmth in our sector as too much polar jet energy) So its not the pure ENSO base state that is important at all here, it is the relationship that the atmosphere adopts to the base state - and this is one that drives a programme of rossby wave trains that should keep punching breaks into the downstream jet and filling them with the sort of ridges that are advertised this coming weekend. With that in mind, there looks to be a very slack downstream void setting up in quite a bit of the modelling beyond next weekend where the attempted phasing of the jet coming across the Atlantic (trying to bump up the strength of low pressure) hits the buffers. A very large percentage error exists here - the European mainland having already become anomalously hot by this time. A ridge, or at least relatively higher pressure is always most likely to reside here, on the basis of the above wave train analysis - so any modelling trying to fire up huge lows and ultra progressively sweep this continental airmass aside should be viewed as just one main source of suspicion. The UK is always likely to be on the cusp of the Atlantic vs European airmass difference, and so no surprise that a uniformly settled picture cannot be guaranteed in any way and is not likely (unlike 2018) - but also no surprise that some NWP will come up with solutions that produce over deepened lows where the phasing of the lows on the downstream jet, clash with hot and humid airmasses. But though it alas takes centre attention due to the vicissitude of NWP, this is simply the noise that masks the default, which will (for the time being at least) be to restore a trough/ridge pattern - rather than progressively try to usher in a low angular momentum jet stream scenario where pressure falls over both UK and Europe and pressure rises sustainably instead upstream over the central and western Atlantic. Please note the deliberately persistent italicised and/or bolded use of word sustainably in this post.
  24. 23 likes
    Superb UKMO this morning! But key features in the extended from ICON / GFS is the secondary ridging North post 168 > 192 GFS implodes the vortex with a QTR
  25. 23 likes
    18z says no to phasing the lows. This really is not your standard Northern Hemisphere . Whether we end up with a proper cold spell by the end of the year or not, this will continue to be fascinating to see this continue to evolve over the coming weeks
  26. 23 likes
    It's great to see all the gang back on the strat thread - I did nag @chionomaniac to join in the fun. @Recretosgreat blog on Severe EU and always love seeing what data crunching . RAM abusing graphics are up next. @zdlawrence prettty much a privilege to have you here Zac, your website is a real benchmark for Strat monitoring after years of peering at the Berlin charts. I think the testament is that even a year on the 3D work is catching the attention of esteemed pros such as Mike Ventrice. I loved the fact that #stratpants appeared this season when last year we had saw the same split troosers ( Scottish for Jeans / Trousers / etc). Best contribute with some commentary too other than say what a great season ahead, am personally loving Novembers now - it's the chase of the what happens next as much as the will it won't it herald negative AO/NAO or a decent winter.. By that I mean the down-welling question and the concentration of minds on this. Stop and reflect for a moment on how we were only 5 years ago working out precursors or Displacement / Split Dynamics.. Loving this ! Gnarly old vortex aint enjoying the Anticyclonic stuff happening right now.. can't do what it wants... Get your crayons out... Not a forecast there are two other years in the mix for Solar QBO similarity...however 95 worth a look..
  27. 23 likes
    yep welcome back @tight isobar another 8 months trying to work out what any of your posts mean!!! can we have it in plane old english this winter??
  28. 22 likes
    Not posted since Sunday but this is what I'm hoping for..this is winter isn't it?...I want snow dammit!!!!!!!!❄
  29. 22 likes
    Yes this type of chart whilst not exhibiting extreme Northern blocking is about as primed for snow in the UK as your ever going to get!
  30. 22 likes
    It's all looking very interesting towards month end wrt to a pattern change. Suggestions of a northerly have been showing up on a few runs. I thought maybe a short lived one at first as the trop. vortex moved across towards Siberia with Atlantic ridging moving in after. Now though with continuing wave attacks on the vortex from both sides we are seeing a building trend for Greenland blocking later on. This along with the Siberian placement of the pv promises a greater chance of a more notable cold outbreak. Some interesting outputs coming out now that's for sure.
  31. 21 likes
    The UKMO now the flattest solution after being one of the most amplified before . The wheels came off as early as T72 hrs upstream with the more offshore and weaker ne USA low . In the grand scheme of things these early differences aren’t going to be a game changer as we are talking about really just an extra day of colder conditions before the high sinks . The winter season if we can call it that has been one of any decent amplification shown even at day 6 range not managing to verify . Overall after this colder blip or snap depending on which model is correct the outlook is dismal for cold . Normally the PV weakens as you head into February but this one looks like it’s just downed a bottle of steroids ! I should add I’d be very dubious of any colder PM flows shown at longer range with a raging PV . This is a model bias especially of the GFS when nearer the time the jet will be corrected further north . Unless we see a big change in the PV then the output past day 6 is to be blunt utter crap for cold !
  32. 21 likes
    Desperation makes a two day northerly seem like a ‘47 redux! clusters show this pub run evolution has about as much chance as anything else in the day 9/11 day period lets look for some consistency tomorrow
  33. 21 likes
    Ec 46 looks a bit more seasonal for jan .....nothing wildly spectacular showing on the means but surface temps are around or a little below average across the U.K. ..... that’s a start !
  34. 21 likes
    Well, after last year's fiasco, I would have thought the -- albeit frightening -- realisation that 'every other long range Professional forecaster' can still get things wrong, might have started to sink in by now. And, that LRFers are human too...? But I guess not!
  35. 21 likes
    So where do we stand today? I can assume everyone on board with northerly outbreak with no snow for most followed by UK high. So where do we go from there.... It might be easier to take a view on where we don't go. The conventional wisdom is that the trop vortex will gear up and give us a wet and windy December hell hole. Evidence from the models, GFS T324 showed a complete marmalisation of the vortex: GEM at T240 has another strong ridge into Greenland with power to add: And ECM T240 has an owl looking unhappy during an enema (hint: identify the mouth): Which is all good. Longer term the MO contingency planners has backed off (slightly) from the October version, and two things that might point towards a colder winter are mentioned, one is solar low - well I've been banging on about that on here for ages, nice they mention it, second, tropical Atlantic rainfall apparently favours cold for the UK - come on guys, I've only just got my head round the Indian Ocean Dipole. Nonetheless, the forecast, based also on model output, and we know what that favours, points to a greater likelihood of a mild wet winter with the caveat that cold dry is also possible, but judged less likely. Read more here: Contingency planners WWW.METOFFICE.GOV.UK Our weather products help contingency planners prepare for and respond to emergencies. I haven't mentioned the strat yet, here zonal winds chart from today's 0z: More members going under! But I know there is maybe an issue whether the GEFS is on the same page as the higher resolution op runs. But the signal increases anyway. So, to my mind, there is still no evidence of a consistent ramp up of the trop PV, yet, and, as evidenced by varying runs above, and on ensembles, evidence of a trop vortex completely at sea. All possibilities remain open for me as we transition on Sunday to winter proper... Regards Mike
  36. 21 likes
    ECM has -5c @850 in situ over the central portion of the UK as the low slides up from the SW With a shallow system certainly some wintryness could be on offer
  37. 21 likes
    BIONIC ICONIC ICON!!! huge heights into Greenland and a nice trough coming down from Iceland,get in there.
  38. 21 likes
    Very cold with some Sleet / snow across the UK... Wait to you see the 850's
  39. 21 likes
    I agree that we weren’t lucky last year. We got about 85% of the way towards the cold blast the models kept seeing, but the split ended up being a bit too far west, and SSTs in the Atlantic conspired with the very cold air spilling out of America to prevent sub tropical ridging on the back of some solid tropical forcing to create the high lat block. I think it was a very fine balanced thing...and we got close but not close enough to tip that balance in favour of cold. I don’t see our current kind of mobility in November as a bad thing at all. For a start it isn’t conventional mild zonality - the trough over Europe is helping keepthe trajectory of the Atlantic assault quite steep with residual heights to the north remaining in play, and we have heights to the east in the right place to upset the vortex. Over on the other side of the globe the North Pacific ridge is set to topple, and a period of Aleutian Low action will also help fire warmth into the vortex. Later in the season what we need is a block to the north/NW/NE that can cause a reverse flow and bring in continental cold and this is very hard to achieve when the vortex dominates. So all remains good as far as I can see, and anyone hopeful of widespread snow right now is hoping for the near impossible. Perfect Synoptics right now in most places would bring nothing but drab, cold rain....so let’s “enjoy” the current setup that is about as good as it could be to set the vortex up for a fall and create the background conditions that could bring something special when winter proper is here.
  40. 21 likes
    It doesn't seem logical take to take the 0600 out of context with the previous two runs and the the ecm After all it was only the other day when you stated 'bin the 0600' because it didn't agree with your preferred outcome.
  41. 21 likes
    To me, the Ecm 12z operational looks even colder than the 0z..hope this trend continues guys!
  42. 21 likes
    The ECM 12z operational might be an outlier of this evening, and indeed may prove by next week to have been just that - but it fully exemplifies (to the greatest extreme maximum!) the scenario I outlined yesterday, and which is also present in sections of the FV-3 GFS suite as well. NWP model suites are simply snapshots in time, and each one develops the themes of the previous suite according to the diagnostic probabilities. So its quite conceivable for even upper air patterns to diverge from one suite to another when an essential part of the jigsaw in terms of the upstream pattern shows a large spread degree of uncertainty. And from memory someone posted a substantial degree of spread of the eastern Atlantic yesterday which illustrated the conundrum of how energy is split with the trough responsible for ushering in the initial (very) warm air advection from the start of next week. Climatology favours the more progressive solution, and it could be that the expected two/three day plume = fresher air to follow does indeed verify, but I wouldn't personally be astonished to see a curveball. This based on the diagnostic probabilities that suggest and support some deceleration of the jetstream across the Atlantic round about the pivotal time that heat advection is pushing north through the UK. This interfering with the distribution of energy in the eastern Atlantic at the key period - and which leads onto that Atlantic ridge late next week to fill the void left by the slowing pattern to complicate things further and help stall the eastward shunt script. And which is clearly modelled on the ECM 12z as well The ECM 12z might turn out to be some viewing entertainment in the fulness of time, but as a few have already hinted at, there is nothing about its modelling within the day 4 to 6 period which is not credible - even if the chances of such sustained intense heat as it shows are likely (relatively) moderated. Or maybe not as the case might be...
  43. 21 likes
    Last time I looked at a calendar, there were 22 days left in this month. I think anyone writing off the next three weeks on the basis that we have had a poor start to this month and then deducing the entire summer is a write off, probably needs to take a step back and consider their expectations. 2018 was extreme if you look at historical years with both the heat and the cold. We are not duplicating that this year so far for sure, but by the same token this also doesn't mean that we can confidently say that the next three months are going to be a copy of the last three days.
  44. 20 likes
    It looks better again later in the run, fingers crossed we see some wintry weather next week.
  45. 20 likes
    Oh no! It's all over again!! Personally I'd like to see the ECM take on thongs (I'll let the typo stand for comedy purposes - I meant things) before I throw in my third winter towel, I have 23 of them left, just so you know.
  46. 20 likes
    I guess you have decide ( if you want to be bothered ) how badly each models nuances are going to impact the overall evolution. I would sum it up by saying on occasion the UKMO tends to be a bit slow & amplified gravitating its 120 > 144 evolutions towards that footprint where as the GFS 00z & 12z tend to exhibit all the bias I highlighted above meaning they are normally a long way East & flatter than the Euro by 168 ( or course not all the time ) The 06z operational is by far the worst with its failings being even flatter & even further East with its solutions past 168. Net Net you would estimate that the likley meeting point of the 2 blended ( exc 06z Operational ) is somewhere towards the 80% Euro plot but often probably not quite as amplified as originally touted at the start - This is of course a long term statistical generalisation covering many years & in certain scenarios where the UKMO excels ( wedge highs to the North ) that meeting point may work towards 90% - however on occasion where the GFS seems to do better that may be nearer 50%. The current output circa 120-168 I would go with UKMO / ECM blend 80% & nearer 90% relating to 06z operational. Post 192 now as it stands the current model tendency ( thats the ECM & more so the GFS ) is to over estimate the eastward position of the jet in which case you would expect that atlantic high to finally end up further North & West than currently progged. With that in mind thats why I highlighting the shift in GFS means as we count down from 204 yesterday as that appears to be the trend....
  47. 20 likes
    Not sure it’s worth taking the current outputs at face value in terms of precise detail , better to look at the overall NH picture which is positive for coldies . The overnight ECM is a big improvement in terms of reducing the strength of the PV and moving it further to the nw. I’d give it a few days to see where the pieces might fall. Writing off mid November cold at this point seems very premature .
  48. 20 likes
    EC46 not too different from the ext EPS knocker posted earlier on. Heights generally to the N/NE with temperatures below average for the first part of November Blocking relaxes during the second half but interestingly a signal for blocking to the east returns during December, though little point worrying that far ahead at this stage.
  49. 20 likes
    Here're the GEFS 12Z ensembles: Eight straight 25C+ days! I notice the signal, for a renewed Greenland block, has all but disappeared!
  50. 20 likes
    So much going on right now that renders over scrutiny of NWP, especially each and every operational output, even less sensible than is usually the case. Yet another occasion therefore to attempt to supply some analysis of drivers, for those who at least might be interested in reading between the lines a bit and looking at some causes and effects, rather than simply wading through a diet of a cacophony of intra day spasmodic gloomy reactions. First of all, if we take a strong westerly phase of the Quasi Biennial Oscillation (QBO) aligned with solar minimum conditions - plus added to that a stratosphere > troposphere profile that has a lot in common with years like 1995 and 2013, then the summer in terms of broadscale height anomaly pattern *should* be on destination to something like this during this summer : If a weak El Nino atmospheric circulation forcing is added to the melting pot which engages extra tropical propagation of planetary waves from tropical convection located within an Pacific standing wave, then something akin to this becomes the framework destination as summer wavelengths really start to engage the closer we head towards July: The former anomaly chart to the one just posted has some similarities at face value to those we have become accustomed to. One highly crucial stark difference is that the emphasis has been for the longwave trough wrapped within that arc of height anomalies to be displaced towards the UK and locked in over us rather than westward placing in the Atlantic and which would make a massive change to warm air advection adjusted our way rather than stuck to our east. Some post analysis, from those that read them, discussed a week or so back, why the trough was displaced in our vicinity, and what it would take to displace it westwards to more closely the blue print composite anomaly that reflects what some will coin/overdub the "background signals" as identified above. The cause, for another further reminder is a combination of persistent override from a dynamic element to the final stratospheric warming, later than usual in Spring - sustained further by a "destructively acting" phase of the tropical cycle on the El Nino standing wave (suppression in the Pacific) which skews the blueprint of the above expected anomaly towards a greater emphasis of Atlantic/Greenland ridge, rather than Scandinavian and European. Furthermore, and most crucially it places the trough further east towards us than the suggested composite. This is redolent of an a-typical La Nina type adaptation of the template pattern that has the crucial effect of making a vast difference between sharing the heat over the nearby continent, and instead being stuck in a cool and unsettled envelope. That struggle clearly evident within NWP - with heat locked in to the east, and despite hints from some NWP ensemble suites, unable to advect far northwards or westwards due to the propensity of ridging to the west and northwest. Hence the upper trough has nowhere to go, but stay in situ, with more and more surface troughs being bred at its base and being pulled northwards within the upper cold pool created. Frustration with the deadlock is understandable, but objectively it is more rewarding, ay least in my opinion, to identify causation though diagnostic approach and probability assessment, look at what is required to change the rossby wavelength, and then once again through the use of diagnostics (beyond the face value identification of the upper air and surface patterns), the probabilities of change occurring to what remains actually a finely poised pattern based on the drivers in play than the computer models might appear to suggest moving forward Its worth looking at that height anomaly cross section and where we at vs the most recent of the years mentioned above - 2013. As we know, putting aside the anomalously much colder first half of Spring than 2019, nevertheless the profiles of the atmosphere this year share some noteworthy similarities in terms of slow speed of strong downwelling into the troposphere - and which continued to scramble the pattern of late Spring and first part of summer in 2013. Now lets take a look at the representative QBO values for both years: Both firmly westerly by this time, and to very similar strength. 2013 -6.07 -1.23 2.85 8.39 12.64 13.38 14.27 14.66 13.12 11.69 12.45 12.55 2019 9.02 9.25 11.82 13.36 14.59 (May to date) QBO Calculated at NOAA/ESRL PSD 30mb zonal wind at the equator, zonal average For info https://www.esrl.noaa.gov/psd/data/climateindices/list/ units=ms-1 Next up lets look at that -ve disconnect to the tropical cycle to the El Nino standing wave and latest EC weekly forecast of propagation timing of the MJO back to the Pacific - returning a more constructively acting relationship to the Nino standing wave and hence re-configuring the downstream pattern to more of an Atlantic rather than UK trough The risk to persistence of the Atlantic and Greenland pattern becoming the default remains failure of the propagation of this MJO wave and what difference it would make not just to any June improvement but how it might alter the progress to a more mid latitude pattern deeper into summer as the template Nino/wQBO low solar combination suggest. But the present forecast from a much more reliable velocity potential component forecast to tropical forcing than RMM modelling, continues to suggest eastward propagation into the Pacific, albeit on a slow time envelope for realistic timing being from third week of June. I'm not sure the MJO RMM deterministic forecasts are especially helpful here, and which underestimate eastward progression - especially around the Maritime Continent and where models tend to try to "stall" the topical wave and interpret loss of signal. This bias tendency will also skew NWP perceptions - hence another reason to treat models with caution who, as is well known, have a capacity for apparent consensus to extrapolate a signal for indeterminate periods of time, and then catch on what is happening and head into reverse. With all of the above analysis in mind, there is good reason to discount the upcoming period as unlikely to change until that disconnect tropical phase is complete - but a lot of evidence and added research to show, that as 2013 suggested into July, it is baseless to extrapolate an apparent persistence factor out across weeks of a whole season, let alone a whole season. Evidence base reasoning is always a more constructive (and enjoyable) method and pastime, and which can always be sensibly monitored for progress and revision according to any further departures from the template - than just pessimistic frustration which offers no objectivity other than based on previous worst case scenarios.
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