Based on American twitter going crazy over the development of this severe NEster I have to assume it has to do with microdevelopments in that feature. Unfortunately we know from experience the atlantic blasting through just as you think we are safe is something that happens all too often. But equally we could wakeup to much more optimistic charts tommorow.

Interesting how this plays out down the line....

Then the jet stream is supercharged ! It’s a shame but it does look ominous

Charts like this suggest someone could experience some cracking snowfalls during the next two weeks, whilst others just down the road* may be rocking the wader look! 

* M4?

Excellent learning, Q. I think this sort of moderation would be helpful in the early stages of this sort of scenario, for all of our less experienced model watchers. Good to see 

Edit - this forum as useless for iPhone as ever 

18z GFS shows a major ssw by +384z:

https://www.wetterzentrale.de/en/topkarten.php?map=2&model=gfs&var=42&run=18&time=228&lid=OP&h=0&mv=0&tr=6#mapref 

That’s up to T+144 -for the GFS  but the ECM is good for another 2-3 days.

Yeah, just gone through each GFS member and they're not without interest. 

Run the 18z chart from +228. Look at the amazing split of PV like January 2013.

The output so far this morning (GFS, MetO, GEM, ICON) fails to even get to -2 at 850 down here out to 168, and even further north it's not especially cold. There is deep cold air around, but it's a Shetland thing - quite a big correction northwards in the end, even moreso than the southerly correction that happened over Christmas. 

A very unsettled GFS 0z rolling out, powered along by a rather angry looking Jetstream!

I'm beginning to fear this one *may* not deliver for those of us who live Midlands southwards, but accept we're a few days away from being able to definitely know what next week will bring. 

I agree. It feels like we're watching this one ebb away. Such a shame considering the potential, though I guess it has always remained just that, with limited cross model agreement. 

Let's hope for some cheeky upgrades over the coming days!

https://www.wetterzentrale.de/en/topkarten.php?map=20&model=gem&var=18&run=0&time=240&lid=OP&h=0&mv=0&tr=6#mapref 

Well I'm willing to give it til Saturday ,but I'm not at all optimistic after what we've seen during the past 24 hours!

I guess while there's still some cold ens all hope isn't lost, but the trend is most certainly not our friend. 

Yes you do right. The 'writing is on the wall' Think I would now prefer things to move on into another phase. Its not hope I'm feeling more surprise. Thought it would be dead and buried this morning. 

Given some of the output we have seen for the last two weeks this was definitely a Jim Bowen spell - we saw the speedboat but unfortunately Dave with the darts hit treble 1. 

If I had to cherry pick a single chart it would be the day 7 00z ECM chart. For two reasons, for the timescale it is arguably the best indicator available from a single chart and secondly it indicates the range of possibilities, from very unpleasant to quite wintry:

https://www.wetterzentrale.de/maps/ECMAVGEU00_168_1.png 

I still wouldn’t call it either way for next week.

GFS Op - On Sun 25th a very deep LP 945 mb develops mid-North-Atlantic with its circulation putting paid to any co-ordinated E-lies, unlike FAX. This LP repeatedly generates secondaries over the following week with quite cold air trapped in local circulations*, any sustained E-lies being confined to Shetland. By the start of next week (Mon 2nd) the main LP has retreated back to the Atlantic and Britain is back to S-ly gales  until Fri 6th when some revival of the Scandi HP produces some colder SE-lies.

(*Local LPs detail, 975mb Cornwall and Northumberland, Tue 27th,  the latter persisting - 970mb SW Ireland Thu 29th, and into Channel - 970mb Hebrides Sun 1st)

ECM - also has a large LP which prevents E-lies developing but differs from GFS in that it doesn't develop secondaries but remains as a unified whole through to Fri 30th with S-ly winds for the whole of the preceding week. By Sun 1st this has filled only to be replace by another LP, closer with a trough across Britain and colder air entrained 945mb west of Ireland Wed 4th but still S/SE-lies. The Scandi HP is absent.

GB News which uses WX charts has backed off from 'feet deep of snow to cover Britain', posted earlier this morning, to 'apocalyptic floods' in its most recent weather prediction.

AIFS - London maxima dropping from 10C now to about 5C in a few days' time and staying there; rain mostly midweek, less wet at each of the next two weekends, winds S-ly at first, going round mostly N-ly from Sun 1st. Edinburgh, maxima dropping fairly steadily from 7C now to 2C Sun 1st, rain on and off until the 1st then drier, winds E-ly until the 1st, then mostly N-ly.

GEFS - In England, temps close to or fractionally below norm, both mean and nearly all ens members, to Fri 6th. Heavy rain in the S for w/b Tue 27th, not exactly dry at other times; in the SW and Wales the rain never lets up. In Scotland, mean and ens members 2 or 3C below norm, rain peaks on 27th , small amounts at other times. Snow row figures grading from about 50% of max possible in N Scotland to about 10% in S England.

Cold rain and S-ly gales appear to be the salient features for the coming ten days or so.

Is the "Ketley High" what gave the NE of Scotland its snowiest February this century? If so that was predominantly northerly air flows not easterly.