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OldMetMan

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  1. Yes I'm still here, just too busy with work and the like. I appreciate the kind comments though, thank you all. This autumn/early winter looks so different compared to recent years, I am impressed by the significant temperature fluctuations up in the stratosphere, not to mention the relative weakness of the Atlantic systems coming our way (apart from Storm Angus of course). I note that quite regularly in runs over the last week or two the GFS has shown a real wintry setup in the longer term, with the jet travelling way south. There's quite an arctic plunge heading into W Europe in the next few days, bit too far E for our purposes but if HP stays anchored close to us and LP going over the top, further incursions of cold air seem likely very near to us. I'm looking for signs of cold air pooling over Europe in the coming days. There has already been very intense HP last week in Russia (near to 1070mb) so if the cold air gets a real chance to settle over Europe, I think it would only be a matter of time before it spreads our way. I've a feeling in my old bones that the weather might make headlines this winter and not from rain, wind and floods as has happened so much in recent years, but "The Big Freeze" type story. I think a really cold winter is well overdue (the last one that I think qualifies as that was 1978/79). I've even beefed up my home heating in preparation! If I see anything I think looks promising in the coming days, I'll be back!
  2. Audaxian, FI stands for "Fantasy Island". The further out the model predictions are, the more they go off into the realm of fantasy!
  3. I felt I had to comment on developments in model output this morning, even though they are tentative and a long way off yet. There has already been some back-tracking on the forecast return of the Atlantic systems over several days, but what I have been watching with interest is the large HP off N Russia and towards the Pole. In spite of the models trying to kill it off, it's still there. In fact, the GEM is creating a new scenario this morning involving linking it to developing HP over W and NW Europe, with a significant easterly developing. Actually, it bears some striking similarities to what happened in January 1947! I can't help but think there is still too much ambivalence over the usual return to the SW flow from the models. I think we need to watch how the upper flow develops in the next few days as this could be crucial in deciding how the longer term will pan out. A big sturdy ridge extending NE, as portrayed by the GEM might seem too much to hope for but as I see things setting themselves up at present, I think it remains a distinct possibility.
  4. Interesting variations in the model output over several days, basically will the Atlantic systems return once again, which has been the consensus today certainly. But I have been looking at both the upper pattern and surface features with strong HP in polar regions, stretching across the Arctic to N Canada, as well as in mid-Atlantic. Looking at this particular pattern reminds of a number of other occasions where pressure builds SE from Greenland and fends off frontal approaches from the SW. There is quite a substantial cold pool developing over W Europe and Scandinavia. The models are sweeping this away far too easily I think, and I expect at least one trough disruption over the SW and subsequent LP activity and the jet taking a more SE path. If this happens, cold air will continue to filter S across Scandinavia strengthening the cold pool. The appearance of a hurricane in the Azores area is remarkable in January. It may have an impact on Atlantic developments and serve to reinforce the upper low over the W Atlantic and strengthen the mid-Atlantic ridging. Over the hemisphere as a whole, there much more of a meridional look to it. I wouldn't be surprised to see the cold air getting more firmly entrenched over the UK with the threat of snow from stalling frontal zones.
  5. Hi everyone, I hope you all enjoyed your Christmas. I have been watching the models well struggle basically, with the developing HP over Scandinavia, coming up with a variety of solutions. It seems pretty likely that the HP will develop, although it is a bit far E, as is the associated upper high, from the point of view of the UK. Given the remarkable persistence of the S to SW flow and the resulting insanely high temperatures we've been getting for the best part of the last 2 months (I have had EIGHT days this month with temps over 15C), I cannot see how this can last much longer, without the upper pattern somehow shifting, most likely retrogressing. The first appearance of really cold air over E Europe has got to mean a change in pattern as I see it. There is still too much energy in the Atlantic systems I think for anything immediate to happen, but if as I suggested above, should the pattern shifts W, and should the upper high take up position to our N, then we may at last have an opportunity for something more seasonal to spread from the Continent, I like the look of the significant upper trough now across the US, and still amplifying it seems. It might encourage similar amplitudes downstream. But again, the positioning of the upper pattern will be crucial. Let's see how the HP holds its ground against the vigorous Atlantic onslaughts over the coming days. Winter may at last arrive!
  6. Hello everyone. I thought it about time I chimed in for the first time this winter. Having gone on and on about a cold spell that never happened last winter, I shall be more cautious in my comments this time around! I have found this autumn and winter's warmth quite remarkable, and cannot recall anything quite like it in my lengthy weather memory. I've been following model output quite closely these last few weeks, as the relentless Atlantic domination continued, but something caught my eye a couple of days ago when the GFS, out of nowhere, decided to treat us to building pressure from Greenland SE, halting the Atlantic systems completely, and streaming very cold air southwards. This development was gone in subsequent runs but there are still hints of it even now: There has been signs of a new trend with model output dithering rather over developments from this weekend onwards. I can't shake the feeling that the GFS had picked up an early trend. There isn't much else to support such a change at the moment. The PV is strong, remarkably low temps of -85C at 30MB, way below normal. It seems unlikely that it could go still lower and there has been much speculation on the possibility of a SSW this month. So maybe January will see something very different. As I said, I kept saying that last winter so don't hold your breath! But after SO much warmth and SO much rain, the pendulum will have to swing the other way - eventually!
  7. I've been keeping my head down for a while, with no sign of any "proper" cold showing in the models, by that I mean, a N, NE or E flow. But recent runs of both the GFS and ECM keeping showing variations on an easterly flow, so as I see it now, the prospects look more encouraging than they really have all winter. The shape of the 500mb flow seems to be slowly shifting, with that small polar upper high re-appearing for the first time in a while, plus the amplifying upper trough over and to the W of us. What's been lacking for much of the winter has been HP in higher latitudes, close enough to us to send an offshoot our way, but instead what seemed like an endless succession of LPs travelling within the Arctic circle. So too over Greenland, where there has also been little chance for cold air to get entrenched and thus for HP to strengthen. But latest runs have continued a trend of showing HP finally putting in an appearance, either over Greenland or off the NE. The problem in the near term is how far east the Atlantic systems will come, will the air ahead be cold enough anyway for any snow, or will it just degenerate into a flabby cyclonic mess, swilling around for a few days before the progression kicks in again! I do think we are about due a Scandinavian HP or something like if the energy goes out of the westerlies for a while. It certainly looks more likely than previous model promises of this which failed to materialise. In any event, I think we will be under the influence of a cold pool (thickness values at or below 528dm) for a while, so there is the promise of snow for some of us. Until such time as the upper pattern stops progressing and settles into a more static pattern, I think we will have to accept short term cold for now. Although the weather has proved me wrong so far this winter, I still feel a more pronounced cold spell will happen this winter.
  8. I wonder if someone could explain something to me, with my very limited understanding of the mechanism of the SSW process? I have noted that the temperature at 1MB has been 35C for 6 days straight, in spite of the ECM forecast dropping it back to less tropical levels every day. Surely temperatures of this magnitude mean something significant? I haven't been studying such charts for very long but I am intrigued by the persistence of such high temperatures. I note also that there have been rises further down in the atmosphere. Is there some kind of tipping point where sustained high temperatures at the top of the stratosphere suddenly propagate downwards and destroy the polar vortex? Or is that the $64000 question every time in these conditions, not knowing if the warming is sufficient to cause such destruction? I find this area fascinating and I realise there is not an exact correlation to events further down in the troposphere, but any explanation would be very welcome! Thanks, OMM
  9. On the face of it, the current situation would look perfect for pressure rises to the NE - slack LP field for the first time on ages over Scandinavia, strong upper ridge to our W, LP pushing NE on its NW flank which you'd expect to build the upper ridge and carry surface pressure rises with it. But alas no, well at least not yet. All the really cold air according to the models looks destined for E and SE Europe - just too far away darn it! But this, as espoused by the GFS-Para looks more like it: Now that is how it should be looking now. It'll be interesting to see if that idea persists.
  10. Some snow fun for some of us tomorrow, with a considerably downscaled LP tracking across us. Although there are model agreements on the developing HP that is predicted for us in the coming days, I can't help but feel that the location of the HP is too far SW and higher pressures look more likely for Scandinavia, and to our N, rather than over us. This would involve a more SW-NE orientation to the associated upper ridge. With so many changes in output models recently, it seems a possibility. With that, of course, a more direct, colder continental flow would happen. As things stand, we are still likely to import some pretty cold surface air. Beyond that, as ever the GFS brings back the progressive flow but I very much doubt it will be that easy. If cold air gets entrenched over Europe then we may at last see some useful (for us) blocking. HP has been stationed pretty close by us for quite a while, I would be surprised to see it remaining so. Recent trends have shown several of the sub-tropical HPs shifting significantly eastwards, the Azores HP included. http://meteocentre.com/analyses/gem/get_anim_analyse.php?stn=PNGZ&map=hnord〈=en Don't despair at the current bland output (apart from tomorrow). I am sure more interesting, colder possibilities will appear soon. Merry Christmas everyone. I hope Santa brought you everything you needed.
  11. The models' ambivalence as to what happens on or after Christmas Day continues. The spectacular looking LP for 27th would indeed be interesting, but I guess the chances of anything like it happening at this distance are pretty remote, although having said that, it is a possibility. What I find odd still is that there have been no real signs within the models of a pressure build from the NW after Christmas. Pressure rises to the S or SW yes, but that is all. Several days of cold air coming S across the Norwegian Sea, LP much weaker over Scandinavia, a situation which has in the past given rise to some noteworthy frontal battle grounds between cold and mild. Here's a nice example from 1982. That one produced significant snow across the S as an advancing frontal zone stalled as it pushed into the cold air to the N. As always, I am aware that no 2 situations are ever the same, and I wouldn't mention it but for the indecisiveness of model output at that time, but it's an intriguing possibility and, dare I say it, no less unlikely than the GFS major storm! It will be interesting to see later model output and whether we have any sort of consensus developing.
  12. The 12Z GEM shows what I had in mind in my last somewhat cryptic post! I would think the LP to the SW might be a little closer and the ridge from Greenland maybe stronger but as the cold air spreads S, the frontal zone would split, with a warm front headed W around that LP. Something similar I remember happened once before at Christmas as cold air pushed the mild Atlantic air away - rain turned to snow on that occasion.
  13. I think both the GFS outputs are suffering from an excess of Christmas spirit. Ah well, no doubt later runs will change it all again. Beyond 4-5 days at the moment with the models is just too silly, so instead I shall look at where we actually are. One thing I found encouraging today is the appearance of a closed upper high north of Iceland. The US ridge is also holding its own and continuing to move E. The wretched upper low over the W Atlantic has finally lifted out. It seems the pivotal moment is around Christmas Eve, as the cold front drifts SE. Is there likely to be a developing LP to the SW on Christmas Day as the GFS shows? Well, I think not, at least not as shown. It still looks to me as if this is where a marked reversal of the flow is starting. What's needed is for a low development to occur to the SW, for that to deepen in situ, absorbing the LP to our N as pressure builds S to the E of Iceland. SE flow then turning E over the UK as the cold air continues to push southwards. That little closed upper high already in place as mentioned is the sign I have been looking for - a tentative indication of northern blocking to come. OK, a flight of fancy perhaps. In spite of the numerous different model solutions confusing things I still believe the trend towards cold is developing and I think that whatever form that takes, the models will have much trouble with it, until it's nearly upon us. Interesting times ahead!
  14. The latest ECM at T240 has that "shape" again - LP strung out across the Atlantic south of 50degN, associated with an extended upper trough aligned E to W. Above this, an upper high stretching from Canada to Greenland, with associated HP. So much depends on cold air extending far enough S, both in terms of its depth and extent. Given enough of a block, and a continuing cold feed down across the Norwegian Sea, LPs in this situation will run NE and glance off the cold block, until finally one runs far enough SE to fully engage the cold air to its N - perfect recipe for a good dumping of snow. Such a situation only rarely works out just right but it does happen and it's a delight to watch. That would be enough for me this winter to see one of those develop, I wouldn't care what happened for the rest of it!!
  15. Thanks Carinthian. Such situations can be very finely balanced. Quite rare are the classic setups like the one I mentioned the other day from 1978 - hell of a blizzard that was! Too often the warm Atlantic air will push into the cold air and win, not before dumping a load of snow. It's a shame they don't last longer! I'm curious really as to why the GFS keeps producing these kind of scenarios, even though they change run to run. Let's see how the models deal with the run up to Christmas, which is still itself a bit open at this stage.
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