Duane S.

Actually that’s got a lot of potential, if nothing else. That could ridge in behind the system travelling through southern Greenland and link with the emerging Arctic heights. That’s the sort of chart that could lead to a spell cold just a few days later. Obviously it’s the ECM at D10, so it’s largely irrelevant but trends and potential is all we’ve got for a bit.

Of course, we all know we can’t take one aspect in isolation (take the very promising wave 2 chart I posted just now). So us humans then naturally lean towards cumulative weighting, our brains can easily cope with that. Imagine each of the following as a 6 sided dice, with the higher the number rolled individually, the better for us and cold prospects… MJO phase E-QBO phase ENSO state Solar cycle As a snapshot right now, you’d probably score something like a… 6 (decent amplitude, long lasting P7) 5 (descending easterlies) 4 (Moderate La Nina, looking like being more E based) 5 (heading out of minimum but still low, despite recent outbreaks) If the average thrown is 14 then we score a very impressive 20. Sure, our chances have definitely improved on paper. The problem, and it is what are brains cannot cope with, is conflict and interference BETWEEN these drivers (and if only it was only this 4 dictating our weather! ). There will always be varying degrees of overlap within that 4, despite them all being capable of being fairly primary drivers in themselves. You will have unknown tipping points all over the place. Throw in the numerous other atmospheric nuances, and that can change the path sufficiently upstream (and thus on to a different path downstream) without us ever knowing exactly why. I know there are analogues that show various combos through the years, but I’ve never been that convinced by them. They are a good guide as to potentially increased opportunities but often little else. Certainly not in the context of the UK and with a warming planet thrown in. It may be this winter a score of 5,5,2,5 would give us our best winter in 11 years. But that exact same state (impossible but for example’s sake) next winter would result in an average winter, because of other interfering factors. Too mind boggling to comprehend. Personally, I suspect we neglect AAM too much (did a drop in net global serve notice on this cold spell?). Certainly for my part, my understanding is not sufficient (Tamara in particular is excellent at interpreting these). Hey ho. It’s all good fun!

Whilst this is purely stratospheric, I’ll post it here for some Xmas cheer after the latest let down . It may have big ramifications for the vortex trying to dictate matters. This is a now a very notable wave 2 forecast . One to watch and why things could get interesting in the not too distant future...

Even the most optimistic and hardened of us must now relinquish our towels. As bonkers as this period has been, a turnaround from here is not going to happen. No doubt some will say it never was (you don’t get any kudos for that though I’m afraid). Yes it was becoming increasingly unlikely over the past few days but the possibilities remained there. Whilst I’m not surprised to see us miss out on a decent cold and potentially snowy spell (we will always need a bit of luck with the timings) I am very surprised how quickly the heights above us are being shown to vanish, I certainly never saw that coming a week ago. Don’t worry though about further lack of consistency, the now forecast long draw south westerlies will of course verify! Still hopeful that after the mild spell we will see January look far more interesting than it currently does on the charts.

Putting aside the quite astonishing and ongoing carry-on for the short-term, I am getting increasingly interested by what could be around the corner. The ECM FI is sniffing it. Height rises from the south next week seem an inevitability, but primed amplification through the UK and beyond could, just could, pay out the jackpot? Watch Arctic heights tease as well. Early 2013 is a decent comparison here. As always we need to get the roll of the dice in addition, but I think this will become an evolving theme over the next couple of weeks. Possibly a very fast evolving theme.

As did I. Very strange chart indeed.

Sorry..but what sort of chart is that?

“They’re likely to” is a bit of a stretch in the current model situation Marco.

Ah, that’s better... Had enough of a couple of constantly negative perennial moaners on here today. For the uninitiated, may I heartedly recommend the Ignored Users List .

GEFS trend is a good trend (don't panic those further north, these are the 850s for the south coast! ) 06z 12z 18z 00z

Possibly, yes, my take it is as well. My post was more to show how much better the EC looked compared to yesterday’s 00z, trending the right way…

Apples for apples comparison in just 24 hours…

The beauty about living on the the south coast is your expectations are so low, no matter what! Even down here there has to be back edge snow possibilities from this, notwithstanding the potential this could trend further south still, if the block has been underestimated. Whilst this continues to be an utter bonkers period of short term model output, I remain at an utter loss as to direction of travel through the New Year period. Better signs regards longevity this morning though, long may that continue. Certainly shows how much the charts have improved over the past 24 hours if we are worrying about mild sectors All the best snow events tend to be marginal affairs, high fish reward and all that. Every year me and @Broadmayne blizzardI wheel out this chart to show it isn’t always about low 850 temps, now seems a good a time as any… This reasonably innocuous looking chart produced over a foot of lying snow and monster drifts for my neck of the woods. A true battleground royale. One other point before the ECM gets going, I’ve seen a few comments in recent days referring to wind direction that have been wrong. It’s worth remembering the general rule that winds flow into a low pressure and away from a high. The correction from the isobars is normally about an 1/8, depending on factors.

This is an unusual and complex set up for the models and professional forecasters alike. This tends to get banded around way too much, as often the models struggle, but I think right now is one of the worst I can remember. And I certainly don’t think we can throw in the towel at this stage but clearly the likelihood of a UK white Christmas has taken a dive with the EC and UK chart output this morning. I’d say the southern contingent are close (but still not completely) to being out of the game for the big day itself, but if I was, say, Midlands northwards, I wouldn’t be losing heart yet, far from… Boxing Day onwards, nothing is decided! This is far from being over.Compulsive viewing.

And that’s the problem with such a stellar run and exactly why we call this ‘the rollercoaster’ and not ‘the escalator’...

Focusing obsessively at each run’s exact track of the low pressure systems is all a bit pointless (other than from purely a JFF aspect), and must actually be quite exhausting! Yes, trends can be gleaned for sure, but corrections, even quite large ones, can and often do happen inside 24 hours in these type of set ups. The focus needs to be on the, soon to be, retrogressed block. If we lose the large-scale influence of this over the Christmas period, it becomes more difficult to pull out a memorable UK-wide cold spell. The more force exerted southwards towards the uk the better. Obviously, within reason, but the envelope doesn’t (yet) have an option where it drops back over us (and even that is no disaster). For me, I want to see a ‘nosing down’ ridge and the rest ought to follow. Not that the weather is ever that straightforward of course!

Very Interesting GFS strat charts this morning, even at 60N (see below) that registers as an official SSW… Does seem extremely, well, extreme though . Certainly one to watch as the ECM comes into range in about a week. Dubious extremities aside, it backs up my post last night ref. an expected warming early Jan and how good that would (could) be in terms of timing . As in, I highly doubt the trop could hold the fort on its own without some eventual assistance from the strat going through this winter.

The 18z is a proper hark back to the 80s. Stunning… This evolution to cold and snow, even as only model runs at the moment, is simply something we are not used to seeing. No stratospheric influence and the beauty is that the tropospheric profile could reasonably lead to an SSW (or a warming at the least) in January as the MJO (you’d imagine) will have progressed (hopefully after a nice long stay in P7 ) back towards the COD through 8 as it hits colder water. That could be perfection as I’d be very nervous if we also had a top down warming coming into play right now. Why would we want to throw in a primary driver with such an unknown quantity, in terms of its effects, when we got here without it? The MJO is all we need to keep things exciting right now (with the other favourable background drivers also in play of course). So, for once, is timing going to actually be on our side??

Indeed BA and this point seems to be consistently missed from many oop North. Unlike us southerners, you guys in the north have a win win situation here (unless it all goes too far north of course, and nobody wins!).

There does seem to be even more complexities and nuances involved in this evolving set up than usual. Notwithstanding it is hardly ever bleeding straight forward getting a fairly uk wide cold and snowy period ! MJO looks absolutely fab for us still. @Battleground Snow has pretty much added everything I was just going to about it, including the ‘problem’ with the 2018 very high amplitude P7 event, which retrogressed our high N and W at warp speed! Amazing few days but over quite quick. For me, I’m just looking at improved ridging southwards from our old retrogressed high. That aspect has improved over the past 24 hours, but a further minor tweak will just add a bit of insurance and stack the dice for a more prolonged spell.

I've had a word with myself. It won't happen again!! Of course it is not really crucial, it never is that far out, but the 12Zs could be a decent pointer as to what happens next. Actually... I doubt that as well really

I hate this saying, but crucial runs later today! Of course, it is quite possible both the ECM and the GFS stick to their respective lines but I feel we will see a shift to closer (closer, I doubt it will be close!) agreement. The heights left around Spain when the GFS doesn't disrupt up against the block is what is causing the then (comparitive) rubbish from the last two GFS Ops. Tentative signs on the 06z suite though?...

Yes, I posted exactly this earlier this morning. This will potentially have large consequential differences downstream, aka us. My only doubt was the relatively short lag from the large MJO divergence (even that is only 2 - 3 days away) to the effects on our weather only a few days later. The good news is the ECM hasn't budged this morning. The NCEP is due out later this afternoon.

Personally, I much preferred the safer synoptics up to couple of days ago, with a UK anti-cyclonic set up for the Christmas period. Letting the Atlantic in with a, by then, less robust block could easily deal a vast swathe of the UK a miserable cool and rainy Christmas. Probably a bit of a nimby comment, as the high risk/reward element here normally doesn’t serve my location well. Especially without any embedded cold in place. The difference between the GFS and ECM could be connected with very different MJO plots from the ECM and NCEP yesterday. Even though it bounced back, the GFS (including its bias corrected plot) dropped back inside the COD in just 3 days time, whilst the ECM maintained reasonable amplitude, about 1.5 SD. Albeit I would concede that pushes the boundaries even of the quicker end of any lag effect. Let’s just hope the GFS (and a large contingent of ens it has to be said) have gone off down the wrong path but it certainly looks at least plausible to me. Goodness me, I started this on D6 or 7 of the ECM. I’ve just taken a gander at D9 and 10 on the ECM Umm, yes please. D10 is one of the best Christmas charts I’ve ever seen. Born from a northerly block building back towards us through Iceland, solid heights beneath us. It would be an absolute classic 80’s event, virtually country wide.

2012? Came good a few weeks later though.