Eagle Eye

I would say 8-12 days or so till we see it properly forming if the current models are correct on the evolution of the tropical disturbance blob as the -VE East Asian Mountain Torque happened a couple days ago and you normally suggest that sort of wave train could take 10-14 days to have a knock on effect here. I'm just going to steal quote @Tamara post a couple days ago. "The question remains long term how far the retrograde evolves and how the -ve NAO behaves accordingly. The intuitive reasoning remains that attritional battle ground towards NW Europe culminates in an attempted breakdown - which tries to re-set to another Atlantic trough and amplifying downstream ridge. Does the Eurasian feedback reload this as another Scandinavian block, or, does the polar jet then prevail and create a more traditional zonal pattern with heights across mainland Europe? Finely balanced in my neutrally objective opinion as much more work will be required from the tropics next time round to assist, with angular momentum at a lower base level than it has been up to this -VE EAMT. Reasoning behind that has been given fully already this week. I don't personally, at this time, believe the Eurasian feedback signal on its own is enough. However, all of that is some way ahead. From my own point of view though, the evolution of the diagnostic remains the focal interest." Perhaps the tropical disturbance may have an effect one way or another but that's even if it ends up doing much. I think the fact that we are back into a +VE AAM and the slow nature of weather may help the Eurasian feedback reload the Scandinavian block but for now I'm going to sit on the fence.

Not necessarily true, re-invigorated +VE AAM could mean that the Greenland blocking is re-invigorated and we get another chance or the relatively same thing happening with a Scandinavian blocking. I think the main thing to takeout of that though is that with a +VE AAM, we're staying away from southerly drag in the GWO phases (northwards momentum but I like to call it southerly drag and I have no idea why) and so the jet should keep itself relatively weak and stay to the south of us. This usually increases the risk of cold so I don't think this one disturbance will completely flip the switch on the Atlantic unless we see further events of -VE frictional or mountain torque in the foreseeable future.

That does make a bit more sense although I think you probably shouldn't call it THAT ECM as we've already seen THAT ECM before, I think yesterday's should forever on be called; The GFS is better anyway ECM

Just watch it get even stronger on the 0Z runs In all seriousness, this can be discussed a length but I'm going to say what nobody wants to hear but needs to be heard, more runs needed.

Ayy yes, seems to form in the mid Atlantic (ish) from an elongated wave of air from just off the coast West Africa. The forcing that seemingly pushes it more extreme seems to almost be contaminated. Look at all of that shearing churning around it, surely scuppering the low's development significantly? The speed at which it forms is quite incredible in itself, a slightly lifting of forcing from the south and we see an almost immediate reaction. SST's wise and we're above average in that area but it's still on the borderline for tropical cyclone development and I know we aren't close enough yet but I'm not seeing too much in the way of a loop current where it forms and that would be my only explanation other than significant forcing counteracting the shearing but as we get closer I think the track should start to shift. That shear is going to shift the Low Level Circulation (LLC) away (in my opinion and that's if it forms in the first place) from the Convective Centre (CC) meaning that the Storm essentially, shouldn't be able to increase it's strength and so shouldn't become too much of a problem except maybe helping dump some snow for us with some slight changes to it's track (only a couple hundred miles and it favours us really). For whatever reason though, the GFS sees it's tail strengthening, perhaps it thinks it's entered a zone of significantly less shear and the LLC and CC push back together and therefore it follows the upper winds. SST's Upper-winds The upper-level winds flow like that, not on their own but due to a divergent wind pattern just above the Amazon Rainforest which pushes up and eventually interacts with that Tropical Atlantic jet. There's so much that can still go wrong with this potential disturbance that I think we could see a flip by tomorrow or Monday on either it's track, intensity or even it's formation.

550 MB, feel very sorry for the fishes. In a bit more seriousness it's just so tight of a system that the numbers are being blocked by one another and the pressure lines but I very little idea how it's sustaining itself in a highly sheared (ish) environment.

Goodness me, makes me feel very young, I was 8 when you last posted I think

I'm not going to say much other than a brilliant GFSrun, I'll let others talkore about it, I'm the teleconnections amateur, you lot are the GFS professionals.

Lots and lots of pages that I don't have the time to catch up with but its clear that excitements building and why not? In hindsight +VE AAM, MJO phases 6/7 causing -VE NAO due to Greenland blocking (not to mention significantly -VE AO) andmost runs now showing a non west based -NAO and you'll have wondered why so many prams lost toys but that's the joy of the model thread, sometimes the pendulum actually swing towards the way of the coldies as we get closer and sometimes the pendulum swings towards the milder solution. Let's see how this pendulum eventually swings on this one.

Sort of agree but 1 day of runs doesn't constitute a trend really. A lot of the more professional on here seem to like following the general trends on 1 run per day such as the 6Z.

I would argue that with such a high risk setup like this, we're still too far out and it's important to note that slight changes aren't necessarily a trend but instead may be associated with inaccuracies still. Models seem to over speed troughs closer closer time for whatever reason (at least in Storm setups).The models can have a mad day as well. We've seen a practically impossible tropical system form in an area of high shearing today, I wouldn't call that a trend even though most models are showing it.

My grandparents live in Buxton as well, I think they pull out a giant snow magnet there for when we go up because it always seems to be snowing whenever we go up there in the Winter. So you can probably guarantee more snow for Buxten beyond this setup if my family goes up there sometime this Winter .

An amazing setup seems to be piecing together slowly, let's hope this becomes a propee trend over the next few days though.

No, me neither,the only explanation is warm SST'S but I'm pretty sure we've seen them this warm before (ish)and a system of that size even with warm SST's would only form around November usually. And anyway, I don't see it as a feasible significant development. It forms in a basin of significant wind shear that would just weaken it,I'm not sure how the models are forecasting it to strengthen really considering that shear wrapped around it.

Oh wow

Webst based -NAO not looking so likely now, fairly +VE AAM which I think has quite a long lag correlation should help sustain some form of blocking although perhaps the MJO phase correlation qith a less -VE NAO now might mean that substantial blocking might come from Scandinavia which is sort of half supported by the synoptic wave train of -VE East Asian Mountain Torque. One things getting closer though and that's the initial setup, it's looking really good for our part of the UK compared to recent December's so good luck everyone, I think I'll be posting most of my updates on here as its hard to keep up with the mad thread at the moment .

That looks really good and another Mushymanrob ramp. 2 in 1 Winter? We must be in heaven .

Toys seem to have been placed back in the pram today. I'd like to proudly say that I never threw any toys out of the pram despite being the youngest here (as far as I know). I know it sounds pretty smug of me so I'd like to say that my longer term forecasts swung one way then the other each day as I looked at more and more opposing teleconnections. I've pretty much always said this cold potential could swing either way and cold is slightly favoured and apart from a few runs the models have backed me up. People saw trends that didn't really exist. To me, it only becomes a trend after a couple days because with what I've seen in the Storms thread (my second home), one day off and things can quite easily pick back up. Perhaps the timing was wrong for initiation, well, closer to time, almost all models seem to over exaggerate a trough's size and the speed that it's moving especially anything from Iberia. Meaning that troughs from the Bay Of Biscay often arrive later than forecast. So we could see that Iberian low move even slower than forecast and I suppose that may help us. I don't wish to sound like the teachers with my class but some people on here need to, "grow up".

Absolutely agreed, people will take 1 run as gospel if it's not showing snow because they think that that must be immediately right. We've heard it time and time again from people who aren't into model watching that they find it hard to understand what is going on with so many different viewpoints, I think people should wait to see the whole model consensus before even beginning to decide if things are backing away from significant cold.

I think we should just pay attention to the pub run every day, that would sort everything out.

Exactly, there's so much difference that it opens up different viewpoints. As long as people remain respectful, it's the best part of model watching in my opinion, I haven't really made my mind up yet. I'm showing the best cold solutions mostly in this thread but also balancing it by providing both sides of the teleconnection signal as it's quite mixed at the moment. Whereas telling my 'crush' who loves mild weather that this cold spell could develop a west based -NAO and it may not be as cold as it could be and also providing pretty much the same teleconnection signal. The pendulum could swing either way each run, high risk, high reward and I will win some way, somewhere whatever happens

That's a positive in my view In all seriousness, a great 18Z GFS and maybe this time, the next EC run will fall in line

Just don't let this be pub run antics otherwise the models will have a hangover in the morning .

It was handed to you earlier along with a glass labelled "half empty".

Tried to find something but there didn't seem to be much away from the tropics. Interestingly, the last ECM major update didn't seem to include any improvement of forecasting vorticity so if it was a problem in mid-latitudes before then, then it may still be a problem now.