Not sure I'd class the 12z GFS Op as all that chilly TBH? Circa 3 days of -5 or slightly lower 850's, with the usual alternating milder/cooler 850's either side of those 3 days. 

Scotland admittedly is colder generally, with the South as you'd expect warmer, with a run of pretty mild stuff (for many) to come over the next 5-6 days.

At a guess I'd say it'll sit in an average spot in the ens - good agreement for a mostly mild to maybe very mild week away from the far north and plenty of up/down scatter after that as LPs wander through and HP ridges in the Atlantic. 

The amusing thing about this week is we finally get genuinely high pressure over Greenland and end up with more prolonged mild stuff than we've seen for a while. If you look just how far south the cold uppers get dragged over the Atlantic it's a little frustrating/amusing. All a little too far West for us this time round

Still the general pattern of mid-Atlantic ridging allowing briefish incursions of colder air isn't a terrible one and may well mean some areas see a bit of snow if the timing is right. 

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12z ECM is pretty wintry tonight with snow down to low levels. 

Crucially, a cold evolution is there by t+96, which is getting into reliable territory. 

http://www.wetterzentrale.de/maps/ECMOPEU12_96_1.png

Could well all change by 00z. Hopefully it won’t!

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Indeed Joe a decent enough ECM , let’s hope it’s the leader with this 

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Indeed Joe a decent enough ECM , let’s hope it’s the leader with this 

Yes, I've seen much worse runs at this time of year.

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Yes, there are quite a few different possibilities in the coming week to ten days. If nothing else it looks like a rather unsettled week ahead and as a result details are a bit uncertain. Messy, and up north rather wet, and generally low pressure dominated midweek.

The cold is never too far away from the north so it won’t take many tweaks for it to spread south and displace the mild air further south.

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The question is, is the ECM leading us up the garden path again with its tendency to overamplify the upstream pattern.

As might be expected, the ECM 12z Op is on the colder side of the 12z ECM ensembles, but the overall spread of solutions has once again shifted slightly toward a cooler scenario in the mid term IMBY.

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Hmm, I sure hope the range of possible regional-mean maximums for the south next Friday reduces tomorrow morning from the 5 to 16*C that can be interpreted from the 12z det. runs and ensemble suites .

As much as some uncertainty is common even at 4 days range in multi-low situations, it's not often we see quite such a large difference in the handling of different areas of low pressure within a trough complex.

 

For next Sunday into the following week, once again a lot hinges on whether the jet stream takes on a S-N alignment (12z ECM) or SW-NE (other models). We've seen the one with respect to this weekend go to the SW-NE variant, but that's not to say that this next one is any more or less likely to do so. 

Yes, ECM has a habit of taking these opportunities the most toward S-N, which limits confidence in such an outcome, but it does represent a realistic possibility.

Beyond that, seeing the likes of GFS continue to toy with mid-Atlantic ridges pushing into Greenland and perturbing the vortex, with that vortex state in turn feeding back onto the mid-Atlantic ridges getting poleward, while some stratospheric warming also gets going as a result of ridges reaching a good way poleward in multiple sectors of the N. Hemisphere, is all pretty encouraging with respect to seeing at least some wintry weather next month away from the usual most favoured spots (i.e. mostly very high ground). I dare not specify anything more than that though!

 

Most intriguing of all is the fact that the vortex at 30 hPa, as shown above for example, was not looking to be anywhere near as disturbed when it was at 10+ days range as is now being projected at 9 days range. That the associated warming is what becomes well pronounced during the following week goes to show how important these adjustments might prove to be for our prospects many weeks from now.

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Fantastic post, thank you 🙂 ! 

http://www.wetterzentrale.de/maps/GFSOPEU18_69_1.png

18z GFS rolling out now. We were really very close to something special. Look at that Greenland High and the bitterly cold NE’ly over Iceland. Brr! 

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The question is, is the ECM leading us up the garden path again with its tendency to overamplify the upstream pattern.

we get suckered every time. Just a question of how long it takes for this one to go Pete tong. The Merkel slug high over Europe doesn’t look like shifting 

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we get suckered every time. Just a question of how long it takes for this one to go Pete tong. The Merkel slug high over Europe doesn’t look like shifting 

 

I'm sure many of us have been watching models long enough to know that if ECM is not on board, it's not happening.  The fact that ECM is possibly the most rampy of all runs should give courage to those looking for cold.  The block appearing over Greenland is clearly difficult to model and I fancy being underplayed across all models.

As a cyclist, I hope it's all garbage and we have 3 months of mild, grey, drizzly dross.

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we get suckered every time. Just a question of how long it takes for this one to go Pete tong. The Merkel slug high over Europe doesn’t look like shifting 

ECM, UKMO and GEM all shift the Euro high out of the way. I'm not sure that putting your money on GFS is logical.

ECM 12z ensembles for London show the op was well within the range of outcomes and very well aligned with the ensemble mean

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ECM, UKMO and GEM all shift the Euro high out of the way. I'm not sure that putting your money on GFS is logical.

ECM 12z ensembles for London show the op was well within the range of outcomes and very well aligned with the ensemble mean

Nothings decided yet for sure but I wouldn’t  discount the GFS after last winter showed when the Euros went off in search of a wintry nirvana only to be trumped by the GFS when it was the lone wolf in the mild corner. Of course that doesn’t mean it’s right now though.

Well a surprise over the last day or so with many of us anticipating a return to conventional zonality. We need to see if the ECM follows the GFS in the day 7 period onwards, the caution I would have for the set-up shown (also by GEM) is that when these come into range, blocking to the West comes under pressure much quicker and topplers ensue.

 

 

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Yes, there are quite a few different possibilities in the coming week to ten days. If nothing else it looks like a rather unsettled week ahead and as a result details are a bit uncertain. Messy, and up north rather wet, and generally low pressure dominated midweek.

The cold is never too far away from the north so it won’t take many tweaks for it to spread south and displace the mild air further south.

Yes - by the end of next weekend and at this time next week, the N will be seeing some wintry stuff, especially on the higher ground with this morning's GFS:

http://www.wetterzentrale.de/en/topkarten.php?map=1&model=gfs&var=1&time=192&run=0&lid=OP&h=0&mv=0&tr=3

 

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Notably mild for parts of England and Wales this week, also quite windy too. Always cooler and quite wet up North, some wintry stuff for usual suspects here. Hints of eye candy in FI, the swings of extreme looking charts should I think be watered down nearer the time to nothing unusual for the time of year.
I would think perhaps 16 or even a 17c may be reached this week in the south, although sadly tempered by the wind?

Notably mild for parts of England and Wales this week, also quite windy too. Always cooler and quite wet up North, some wintry stuff for usual suspects here. Hints of eye candy in FI, the swings of extreme looking charts should I think be watered down nearer the time to nothing unusual for the time of year.
I would think perhaps 16 or even a 17c may be reached this week in the south, although sadly tempered by the wind?

I’d be surprised to see a 17C, although it’s possible on Thurs in a sheltered bright eastern location for instance.

In the same way I wouldn’t be surprised to see some substantial snowfall across higher Northern areas from the weekend as the models continue the downward trend in temperatures nationwide as we head towards December.

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Yes some good agreement on a colder plunge this morning. 

GFS - http://www.wetterzentrale.de/maps/GFSOPEU00_120_1.png

ECM

http://www.wetterzentrale.de/maps/ECMOPEU00_120_1.png

MetO 

http://www.wetterzentrale.de/maps/UKMOPEU00_120_1.png

GEM

http://www.wetterzentrale.de/maps/GEMOPEU00_120_1.png

JMA (t+84)

http://www.wetterzentrale.de/maps/JMAOPEU00_84_1.png

There isn’t a single one of those links above that doesn’t show some promise, and we are now lurking in semi reliable territory. Interesting times, but the usual caveats apply i.e. things could look very different in time for the 12z suite.

MetO output is currently least keen, ECM and GFS most solid runs this morning. 

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The GFS ensemble has flipped back quite spectacularly this morning, with the cold cluster now predominating.

http://old.wetterzentrale.de/pics/MT8_London_ens.png 

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BBC weather not buying in to the cold plunge fully... said it was mentioned yesterday but they are not so sure now.  That's some flip in 24 hours, both by models and the Beeb!