Duane S.

Good grief, it's hardly 'folklore', I have seen it with my own eyes on countless occasions. Your previous comment that probably 100-200 members are ideally required speaks volumes... Happy Christmas to everyone!

As per my post of a few days ago, it is simply all down to the potential vertical WAA surge up into the pole, a decent injection such as recent forecast charts have been showing cannot occur without consequence for mid latitude areas. Even if we have to endure further toasty conditions in the process and see the cold flood down way to our East, the odds for a cold spell occuring here soon after would shorten massively. A repeat of Jan 1987 should not come as the biggest surprise should it happen (unlikely still but there remains the potential with this set up) To my mind the MJO looks to be the main player here and with most models seeing no real let up in the ppn as it drives through the Pacific, January looks to be starting on a very interesting note indeed. As others have quite rightly said, the Ens as a whole are as prone to flipping as the op, which naturally somewhat negates their usefulness! Not always of course, but often enough...

Does appear the models are finally starting to play about a displaced to the west Azores High, this will likely be a response of the MJO likely to head into phase 6 at a decent amplitude in about a week or so. I expect to see more of this in coming days. Whether in reality we get that connect and even if we do, what sort of mid Atlantic ridging is achievable with the vortex aligned where it is, we will have to wait and see but it can only be good news for the the most important initial stepping stone to something cold, the removal of the Euro heights.

Slowly but surely hope is emerging. The difference is that 1 week ago the succeeding 10 days was set in stone, as in there was virtually 0% chance of any meaningful snow. Roll on 7 days to today and the same certainly cannot be said of the next 10 days (from the end of the month onwards). Maybe not enough ppn to beef up the base for my week in the Alps from the 3rd of Jan but at least there is a decent possibility that the Euro high will have shifted and the temperature will drop down to something more seasonal.

This could get interesting... Member 18 is obviously extreme and highly unlikely but... it is not without foundation. It will likely pivot around just how far towards the Arctic the WAA can reach. I think there will be a tipping point here. Most still have it getting around Northern Norway, this will most likely be flattened out and we we return to type. If though (BIG if) we can get it piling right up into the Arctic itself then it is potentially game on. This is what we're looking for and has support. Something like this may well be a big outside shot but unlike most cold setups which are capped a lot higher (temp wise), there iis a Jan 1987 scenario here. An Arctic High (albeit this wouldn't be in its truest form) often frustrates but occasionally can produce the jackpot. I'm reading this as the ridging up into Scandi is all but nailed (small blue circle), but how far it gets is anything but (red, high spread area around Svalbard)... It would mean enduring potentially even warmer uppers first but I think most of us would happily take that for a decent shot at this! Worth adding that any further amplitude of the MJO out of Maritime into the Pacific could well help provide the extra boost required here. Even without increased ppn, the current forecast from most models is already looking pretty decent. I think the best way to look at the MJO potentially going into favourable 6/7/8 territory, whilst we may end up with a 'disconnect', it is unlikely to be detrimental, unlike other phases at moderate to high amplitude.

Well, the weather chart gods are not exactly getting into the festive spirt at the moment. My finger is hovering of the cancel holiday button as am due to fly out to the Northern Alps on the 3rd of January :-( Going to give it till Boxing Day (in hope more than expectation) but it is now evident that am now going to need an almighty turnaround ASAP to remove that high in the short term. The Atlantic low is only going to contribute to matters as it continues to feed it for the foreseeable. For the UK we have to be thinking no pain no gain here, hope for strong vertical advection of warm air to our East (to our west will likely just be flattened and the effects negated) into polar regions and forget about the inevitable associated warmth this will bring. This will at least shake up the NH profile to one degree or another and MAY, just MAY be the the first falling domino of the xx amount needed to bring in a proper cold spell.

Come on folks, from our current sorry state, if we can't wax lyrical over this 12z GFS run, then I'm not sure exactly when we can. Of course it won't verify like this but tie it in with the ECM's recent output, MJO forecasts still looking promising (best 2 below) + It is not without decent support... and things are starting to look up, perhaps a bit earlier than expected? No surprise to see where the biggest spread is and at what time-frame...

Fantastic post by Tony above wrt Strat vacillation. This vortex is going to take some taking down that is for sure. As expected it is now a fully mature self propagating absolute beast. Fascinating period of model watching coming up though... It's always interesting to see what happens next as convection trundles eastwards through the tropics of the SE Asia region. Not only is this phase its greatest test (i.e. not to fizzle out and drop back into the COD) but it is also probably the worst area for accurate readings. Anyway, my fingers are also firmly crossed we can get into the Pacific at a decent amplitude then we should start to see an increase initially in charts depicting WAA up into Greenland hopefully then followed by some proper Scandi (not Sceuro) High action.

Well the ECM op has lifted the spirits a bit this morning, with a very interesting take on things.The ridge likely still to be flattened if it continued but you could see a further and more serious bite at cherry emerging 1st week of Jan. Amazingly D8 is nearly a cross polar flow... Fingers crossed this is the start and turns into a trend in the coming days.

Ok it's 'only' the 18z, ok it's only one GEFS member but in times like this you've got to dream...

Very decent wave 2 forecast this morning from the ECM...

This gets banded around every year. The vast majority of the time incorrectly, however this is as close to a proper one setting up as I've seen for a while. Hopefully it won't get to that but IMO it has to at least be a possibility this time around. The mid month window of opportunity for a cold spell is all but a distant memory, we need the minor strat warming due in a few days time to be the start of the fight back against it. Get some wave activity going and stop the raging vortex having it all its own way. There are tentative signs but alas only that right now.. Hopefully we will see more of this in the coming days... If only for something nice to look at least :-)

I'm assuming all areas of the Alps must be suffering, from the NW Alps to the SE? Difficult to see it changing for a good 10 days absolute minimum. I thought the start of last season was bad but this could be a lot lot worse, at least there was a good dumping just past Xmas from that trough that dropped South through the Western side of the region. Right now, apart from some sporadic frontal ppn, it looks incredibly dry and grim for the festive period. Im off to the Portes du Soleils first week of Jan and whilst that isn't on the weather chart radar quite yet, one thing that looks like it will be missing is a decent base. Of course, plenty can change but this displaced to the east slug mid Euro high is exactly what a strong Nino often creates early winter so it is difficult to see any abrupt change for a while yet now it is firmly established. Change can does and will happen though so all eyes on the 10-14 day period for any emerging trends...

Quite unusual u wind profile forecast at D10. Raging vortex but seemingly unable to filter down and getting confined to the top. Talking of the top, best warming prediction I have seen so far this morning, a bit more of this will likely start to do some damage...

The pesky W-QBO winter 13/14 vortex was producing similar strength wind, give or take the same time of year...

It's all about a window of opportunity in these situations. Mid month (ish) has been earmarked for a while now as just that. The vortex is likely to move away NE, the duration of which is undetermined as is how much energy will be left over in the Greenland vicinity. That will partially dictate whether or not we can only muster a fleeting mid-Atlantic ridge toppler or something more akin to what the NCEP Control has been showing is still up for grabs IMO, albeit not the most likely outcome.

And yet again the Control run comes up trumps, it is being consistent at least...

OTT amounts of dispondancy on the forum this morning on the back of a couple of (admittedly dire) GFS op runs. ECM screams potential again and pattern change still incoming just beyond mid month IMO. Of course what constitutes pattern change for some may not for others and I don't envisage anything 2009 / 2010 esque but I do see a gradual removal of the European slug as we head through the 2nd half of the month.

Wow the 18z Control run has certainly been to the Xmas party! Still liking the idea of the formation of a mid lat sceuro type block, part courtesy of some upstream trough disruption. We would need to roll a double 6 and some to get quite this lucky though... However, albeit unlikely, it is at least feasible, the window of opportunity for this period well and truly open.

+1

The Control run along my lines of thinking... Mid Strat coming under a bit of pressure towards the end of FI, one to watch... I'm surprised actually there aren't a few more posts following the 12z suite. All in all very decent output and bags of potential, all things considered!

From where we currently are and teleconnections as they are, there is little sign or chance of a pattern change to sustained HLB for around 2 weeks time. But the signal to break down the Euro high remains and that could be hugely important going forward. Small steps. So whilst a PM airflow looks to be the most likely of the colder outcomes for the mid month period, we could perhaps squeeze a decent mid lat high pressure out of this, bringing in more seasonal continental airflow for that period to the southern areas.

Starting to warm up nicely at the top, would be nice to see further increases in the coming days and, of course, it actually verifying...

Intriguing! Especially considering (I would have thought) that the current Enso state coupled with this W-QBO would have produced this response for early December anyway? Interesting to think that another primary driver might be at play here.

Certainly not convinced HLB is 2 weeks away but sure am picking up a trend that lower heights will be slipping into mid Europe by then.