weather eater

Hi Tamara that may well be, only a fool writes of the rest of winter in mid Jan but I was only commenting of the model output we see from the main models for the next couple of weeks and the lack of any real pattern change we have seen over the last couple, despite being occasionally tantalised by the models. For myself I just enjoy model watching, cold and snow would just be a bonus, I certainly don’t often get sucked in by it.

Trouble is low confidence does not mean cold and snow are hiding around the corner waiting to pounce and a spread ensemble suite also doesn’t mean that either, I wouldn’t mind a tenner for every time the ensembles had been touted as a savour on this thread, only for them to have no more meaning than just following the ops. Yes there is uncertainty, there is always uncertainty past 96hrs or 120-144hrs it can vary a bit and nobody should be giving up the winter or even the next couple of weeks based on any model projection that would be foolish, but I think its far to say that there is very little in the current modelling to suggest a major change is on the way, just a few hints that there is some possibilities.

Except frosty there are no confused op runs, least wise no more confused than they are any other day of the week, in fact I would say the ops are pretty steady in high res and low res is irrelevant, as we have seen a number of time already this winter and we can only report on the models we can view.

I think the problem for many Mucka is that a pattern change has been touted for the last two weeks and all that has happened is that we have swopped vigorous zonal for less vigorous zonal, with a very real prospect of a return to a more vigorous zonal looming on the horizon, although somewhat more PM at times. I note IF again alluding to dear old Shannon E, however the output in high res looks pretty consistent to me at a time when I would be expecting to see more variation with Shannon in town and any pattern change to something colder seems to wither on the vine as soon as we get below 144hrs give or take a little, so it’s no surprise to see doubt creep in with regards to posts suggesting just wait a little longer. I have to say to everyone that that’s all there is, model projections can never be trusted beyond 120hrs and its perfectly possible that a surprise gift is just around the corner or just another steaming pile of crud, only time will tell, fascinating isn’t it, least I find it so.

Tonight’s 12z ECM run looking very similar to some recent GFS runs especially at around the 240hr mark, it will of course change at that range, but if it comes close then it will be a big coup for the GFS in regards a pattern that could affect us, whatever the verification stats say, every dog has its day sometimes.

I think that may just be a little daydream you have just before going off to sleep. On a serious note some, interesting modelling this morning from both the GFS and ECM, the GEM also, the whole will it, won’t it easterly is as usual, an evolving situation and as far as I can see what we want is to see Stella charts pop up at 72-96hrs. Stella charts at 144hrs plus will fall over 90% of the time, my advice at the moment (actually at anytime) is to view anything post 96hrs with a large pinch of salt.

The most important post of this evening in my book, basically the outlook is not great for cold but the cards are in flux and its a case of waiting to see what side is facing up once they fall.

Poor again from the 12z, just goes to prove the point that it’s no point in chasing easterly’s modelled at 144hrs plus. Really what the models runs are, is projections for the evolution of synoptic patterns based on the starting data of the run. The trouble is by the time we see a model run and start to discuss it on this thread, that starting data is already out of date. Now of course the ensembles are supposed to help, but if you don’t know how the start data is wrong then you can’t make a judgement on which of the ensemble perturbations is the nearest match, at least the bulk of us don’t have that skill, mostly what happens on NW during winter is that the coldest ones get talked up and the milder options get swept under the carpet. The saving grace here, is that the evolving doesn’t stop, so whatever this 12z operational is projecting it is increasing wrong past day three or four, and with 6 weeks of winter left and potentially early spring as well, there is still plenty of time for the weather to spread a little joy and happiness to those looking for a bit of cold and snow. Alternatively for those that have them, you could try paying extra attention to your partners and loved ones, I always get more pleasure from mine than I do from the weather, even if there are six foot snow drifts outside my door Cecil Hogmanay Melchett I sympathise I really do, it’s raining again here now.

Three problems as far as I can see, cold air to tap into, the block is not quite in the right place and the big flabby low to our west on the 15th. Yesterdays 18z elongated this but the GFS and the ECM this morning have it as a round dartboard feature again and that’s not helpful. However, the GEM still has it elongated, I’d rather we were not pinning our hopes on just the GEM making the correct call but that’s the way it looks this morning.

Now what was it I said at tea time, "The Low pressure system being modelled to our west at 132hrs which was elongated in earlier runs allowing it to undercut in the way we want is now rather round, not good, but the likelihood is that its shape and track will continue to evolve over the next few days", This really is the crucial factor for viewing the models, EVOLUTION, no matter what they are showing, even if that appears to be at a short range, whether good or bad for cold prospects, the synoptics will continue to evolve, every run, every day all year round.

Tamara I love you, my thinking exactly, how much more interesting is model viewing now compared to only a few days ago. I have to say what on earth were people expecting after yesterday, did they really think it was just a case of reeling the easterly in, perfect and formed and a straight forward count down from projection to reality, it never happens not ever. Perfect synoptics at 144hrs are useless and while there is a good chance that we may now see nothing but more downgrades from here on in, there is also a chance that it will all slot together as we get into the 72-96hr stage. And even if that does not happen, as the patterns evolve then new possibilities may open up, I think we can see that from how this ECM evolves, it wouldn’t take a great deal of change to develop into a big fat block running from Greenland to way out east. Plus it’s got me really interested in this community again, even if one or two of you drive me mad with your positive, negative, glasses up or tip of nose model viewing methods.

No it’s poor, big round LPs no good to anyone, but it’s at 144hrs, there will be more changes, let’s hope more favourable one’s.

Seems to me the crucial stage is in regards the shape and track of the low pressure system at 132 hrs, now that may well resolve itself this evening but we are not going to know for sure for a couple more days.

The Golden rule of model watching is, whatever the models are showing at 72hrs plus is going to change and when we we are talking 120hrs plus they are going to change substantially. If you follow that rule you shouldn’t get surprised or disappointed when cold runs go to pot and you shouldn’t get bullish about them verifying either. If you apply those rules to today’s 12z GFS output, then whatever the synoptics being modelling are at 132hrs, those synoptics are going change over the next few days, they may be poorer, they may be better but they will be different. The Low pressure system being modelled to our west at 132hrs which was elongated in earlier runs allowing it to undercut in the way we want is now rather round, not good, but the likelihood is that its shape and track will continue to evolve over the next few days, give me pragmatism over optimism or pessimism any day of the week.

At 144hrs the 06z is much the same as the 00z, spot the difference, over to you Mr Murr.

Not really, unfortunately it’s not as simple as that, it’s perfectly feasible for a model to be consistent but consistently wrong at the same time.

The GEM is a decent model and I’m sure Steve can point you at some excellent verification stats, however, yes of course people are going to post up GEM charts when it is showing the best evolution, who can blame them.

Well we are starting to see a familiar story this morning, some great runs at days 5,6,7 then the tweaking and the fine tuning start to kick in and all off a sudden things don’t look as good as they did, it all starts to get a bit jam tomorrowish. We need to get the Stella charts into the 72hr range where the tweaks are small. What we have now is a slower evolution, however, the charts for days 7,8,9 are all also going to get tweaked considerably, so I wouldn’t bet on the idea that it’s just a case of waiting a bit longer and that a full blown easterly is still in the bag but just not as quickly. Having said all that the GEM is still good this morning and we still have time for the GFS and ECM to make a correction back towards the kind of charts we saw yesterday morning and it could be argued that the models have just reverted back to a slower evolution, so we just got a bit spoiled yesterday, let’s hope so.

Sorry about this I really am but I just have to post this again, Posts having a go at other members may be popular but they do nothing to aid the discussion they are not even humorous. So a small plea because with the models trending in the way that they are this place is likely to get very busy. Can we just discuss the models without berating others just because their interpretation of the models is different from yours, or because they choose to highlight other areas other than cold and snow. For example when the pattern will or looks likely to break down, or berating them for not being positive enough, the clue to what this thread is about is in the title, positive and negative have nothing to do with it, and while people making posts just to wind others up is dull and we know they do, so also is reading through pages of tit for tat moans or having digs at people just because their preferred weather type is not the same as yours/bulk of members, it’s not a closed shop, there is not a rule that only coldies can post. OK I’m not a mod, so I guess that some members will think that I don’t have the right to make such a plea, but I am a member who would have a lot more posts to my name had I not got so bored and jaded with bickering, bickering which has a tendency to increase the more the models point at a potential cold spell.

Just to touch on the ensembles again, the operational run is the best guess based on the data, the ensembles are the same data tweaked (maybe Twerked), at the moment the ECM operational has support from most of the other models operational runs, I’d start worrying if any of those start to pull up an alternative evolution and not worry about rogue ensembles.

As for the ensembles I never look at them, but the fact that some (or even a significant number) of them don’t buy into an easterly should be no surprise, it would be absolutely remarkable if they all supported the op not to mention deeply suspicious.

I very popular post frosty but who is it you are talking about because I've seen no posts of that nature in this thread are they are in the mood thread?

Don't know about you Nick but the UKMO 120hr and 144hr charts never fill me with much confidence they never have.

Only because he's seen it on the models, same as the rest of us.

One would hope not but it’s been known, I'm not so much worried about being lead up the garden path but a little concerned about how big an impact the tweaking of the synoptics over the next few days will have on what we eventually get, (Notice I said tweaking there not Twerking, as that would be deeply unsettling).