It's starting to appear as though the breakdown, if there is one, may be getting pushed back further yet again.

Worth remembering also that some model runs early last week had the current cold spell ending either today or tomorrow. No wonder the Beeb seemed to be not so sure about developments during next weekend at lunchtime today.

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Yes, at this rate the high will never leave us and build into Scandinavia at the start of next week.

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UKMO 12z on WZ:

http://www.wetterzentrale.de/pics/Rukm961.gif

http://www.wetterzentrale.de/pics/Rukm1201.gif

http://www.wetterzentrale.de/pics/Rukm1441.gif

Looks as though HP may be attempting to build back in eventually here too.

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With the continuing uncertainty around the high pressure, the reliable time period is still relatively short.

I wonder what Beast's thoughts on the current runs are. From the way I interpreted many of his posts at the end of last week, he seemed to be fairly certain that there would be no backtrack in the models from the breakdown to a more unsettled spell late this week/next weekend that was being touted by most GFS and ECM op runs at that time. Doesn't seem to be anything as clear-cut now, if it ever was.

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hope so David!

some dry weather would suit most areas I would think. Perhaps some frost and fog thrown in- again a fascinating period of model watching 

Epic GFS Control GAME ON!

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=216&mode=0&carte=0

 

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GFS 12z Control is an absolute peach at T216!

Edit: Only perturbations 1 and 20 offer a similar outcome on the run.

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If this was a game of darts, that chart would certainly be worth one hundred and eighty!

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Indeed doesn't quite go the way I hoped after but a stunning run nevertheless

 

 

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GFS wants to give us all the high pressure we missed out on in 2015 at once! 

It basically gets stuck in a cycle of repeated attempts to build the high north but without the ability to resolve the split jet scenarios needed to do the job properly. Always a good sign to see it trying, IMO. Especially when you know that there's a good chance the amplification from the Pacific sector is being underplayed in the longer term.

UKMO is fairly similar to GFS on day 6 so not much to be speculated upon there.

Could ECM's tendency to go wild with amplification trends produce an epic run soon? The potential is there... though it's fair to say JMA won that race last night 

 

There could be a long run of frosty nights in some places while we wait for the next spell of high-latitude blocking to develop. I'm sure many will find that far more enjoyable that a run of relatively cloudy southwesterly winds. I'm really liking the idea that we could see an extended period with a lot of clear skies, as that was sorely missing across the majority of last year, and this weekend's attempt was trashed almost before it got going (but Friday was good, a taster perhaps?).

 

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Just seen that control run. What's interesting is that as well as offering the potential for a lengthy cold easterly, the alignment of the flux into the stratosphere is altered and this brings that second bout of warming further west:

 

While it does take longer to kick things off (but does the control have the same strat. resolution and levels?), this outcome seems to be better for putting pressure on the vortex and causing it to stretch out. There's a greater chance of a split taking place going forward from that which tends to be better for getting HLB in the right places for the UK to see an extended cold spell with decent and widespread snow chances.

You see, Feb still holds the greatest potential to deliver us that sort of weather based not only on the stratosphere but also the expected behaviour of tropical forcing. The latter could even do the trick without the former and I have found myself wondering if the strat. events might end up being a needless complication. How typical would that be? 

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Nope, it was never clear cut. I myself thought we were a shoo-in for a milder spell of weather to end January, but remained more hopeful for February. As others have said, it's not so clear cut now and there is plenty of interest in FI 

 

Possibly wishful thinking, but to me it feels like maybe we are in the midst of somewhat awkward, messy, and hard to forecast transitional period. Transitional from the mildness of early winter to hopefully a cold later winter.

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That's how it seems to me Brendon and some of the more experienced posters on here have cautioned about that for some time- the inconsistency between models at times, the persistence of the cold high, disruption to the PV and splitting of the jet among other factors.

Keep thinking wishfully- it was really a near miss for the south this past weekend, on the geographical scale of things. Remember a slight kink, loop or coil in the alignment of a HP or LP can mean a hundred or more miles difference.

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And at the 30 hpa level for the 3d Feb, the stratospheric vortex is plotted to having the life beaten out of it. Again, it's in FI range, etc, etc, but is "fun to look at". Would have thought that will pique our Quantum's interest as he likes this kind of forecasting level . . .

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Hi Ian. I'm not really up on this so please excuse my ignorance bit doesn't the warming need to take place on our side of the pole for high pressure to form in a favourable position for UK cold. Surely the cooling element on our side would promote a strong PV to our north ? 

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Hi Steve. My thinking is that when the cold core of the PV at the 30 hp and 500 hpa level kept nosing into North America in the winters of 2014 and to a lesser extent in 2015, it then has the effect of sending deep cold further south over there and then onto promoting cyclongenesis over the Atlantic.
  On this occasion, I must admit that this is entering uncharted territory and am wondering what this would do for us should this actually come off? Will it have the effect of pulling deep cold our way in from the Arctic, or will it just simply encourage a strong westerly flow? It's just something I'm "trying out" for myself as that set up at the 30 hpa level is quite different to the last two winters.
  Of course, that's all in the forecast range and not happening right now, heck, it's not even the stratospheric warming we are looking for. It's like I said, it's just for fun stuff and probably be yesterday's news tomorrow.

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Hopefully, it would deliver a Scandinavian trough and bitter northerlies for us - but that is just pure guesswork.

 

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I think it's more of a matter of how the tropospheric polar vortex gets rearranged, if and when the stratospheric warmth descends to that level. That seems to depend on a huge number of variables, of which location of the initial warming is just one. I don't think it's at all negative that the stratospheric warming takes place on the opposite side of the hemisphere from where you want it to descend.

I wish Matty H hadn't been so abusive to people who tried to make educated postings about the strat on this forum. Then I maybe wouldn't be as ignorant about all this as I still am now.

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In a full on SSW the temps at 30 hPa could reach near zero Celsius to Brian may need to adjust the scale to account for that... 

 

I agree with BHB with respect to being in an awkward period as far as the modelling is concerned. Basically the models are struggling to comprehend what is an unusual situation across the tropics at the moment, with multiple Kelvin Waves that have emerged from that big MJO event of the past couple of weeks adding a convective signal to the Indian Ocean at the same time as convection also persists in the Central Pacific. The balance of power between the two seems to be causing the models some issues.

In theory another MJO event is likely initiate sometime next month and propagate east across the Pacific, but at the moment the models aren't really seeing it and are, to be frank, a total mess:

In the meantime, the CP convection associated with the SST warm anomalies in that region and extended Pacific jet (with precip anomalies extending unusually far north for an El Nino event) looks likely to bring about a pattern that drives a strong mountain torque event in about a week's time. For the purposes of this thread, the main things you need to know about that are that it brings about a considerable increase in the amplification of the pattern, and that it tends to be underestimated by the models in the mid-range (let alone longer range).

I expect that as the time draws near, the charts will start to get a whole lot more entertaining. You know - one of those 'wake up and smell the coffee' moments that we enjoy so much on this forum 

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ECM ens quite interesting. A few runs never bring the breakdown.

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It looks like the weather models are better for people in areas affected by the recent flooding as they show less rain.

In terms of weather interest though they are a complete disaster. High pressure close by to the South, completely in the wrong place for any real active cold and also too close to allow any real weather in from the West which may have some interest with some polar maritime airstreams. These synoptics are just wasting the best weeks of winter; I believe it is unlikely that February will be any better. In recent years February is always a boring month for weather.

Roll on Spring!

Wrt the section I've put in bold, I can recall a month or so ago that some people were saying that January would be a write-off for cold much as December was. January thus far hasn't delivered a classic cold spell, but at least we've seen something a bit more seasonal this month.

At the moment, we can't even be completely sure about next weekend's weather, let alone next month's.

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I've been watching this for a few days and its extremely interesting but am holding off talking about it too much until I had read Judah Cohens blog. Essentially it is suspected that there will be a final destruction of the polar vortex. 

And its quite interesting, that I started talking about the polar vortex weakening at the end of December and the trend is predicted to continue into February, albeit at a different level.  

https://www.aer.com/science-research/climate-weather/arctic-oscillation

 

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