Yes, but what about those 'pizza slices'? Could they throw a spanner in the aul works? 

Four Seasons in one day...

Good overnight runs, a good chance now of a short sharp cold snap followed by a milder interlude then hopefully a more meaningful cold spell helped by upper atmosphere events 

ECM 00z ensemble for London

Quite a significant change from the 12z with markedly more uncertainty about the cold spell that may/will/could start next Monday.  The solid clustering has been diluted and there's more scatter, so clearly uncertainty about the build and positioning of the blocking high.

At least the op was not without support.

Spot on.

How many times have we had the Atlantic go over the top of a high that's built in from the east, toppling the high and diverting the colder air into Europe? Worst possible scenario. Much better to have the energy go under the high to keep the block to our north, a la Jan 2010

Pizza slices usually fold up into occluded snowfests in the face of a strong block....

These situations develop very rapidly and land within a few days of appearing on the charts, so always attracts a degree of excitement.  The foundation blocks to enable this - i would say, is almost there... 

we just need that injection of cold air out of the artic/siberia....  

the latest run almost gets there (you can see a plunge about to skim off northern scandinavia)

In the past thats mainly been due to a certain European HP which aims the energy above the block, and essentially allowing the scandi HP to link into the EURO and die.

This season has been all about the lack of European Highs, (touch wood) Theres been alot of unsettled weather in the Med since last year.

Was expected to be slightly more unsettled in Med given the sea temps hopefully it can last

I'm starting to get the impression that you quite enjoy posting that?

It's the spoiler HP over the Alps that does it. (Remember the Berne pressure index?!)

UKMO and ICON 12z both have similar ideas with that low west of Iceland

Of Course, that was from the days of the eternal Bartlett pattern.  Nothing remotely like that on the cards - so far.

Theres signs of that cold block i was talking of.  The cold air looks alot more established (but needs improving) a broader swathe of cold air takes hit into Scandi.

fronts are forced under the block, but quickly give i an upper cut as its perhaps not strong enough just yet - needs to establish itself a bit, more, also missing an injection of seriously cold air... Still looking weakish from a cold air pOV

Very progressive though and very encouraging to see... this is only a week away!

These charts to me always give a good indicator of how cold the air is.  0* Isotherm.  Or rather how much its taken hold of the land mass.

You can see the same time, 6z vs 12z (right) the cold air seemingly a bit more in control.  More purples and less fractures please :)

Another Month and it would be all pruples rather than mixed immature cold air with blues in.

Sorry about the 3rd post in a run....

But had to also post this.... Remember all those LRFs that Gavin has been posting on his videos... all those +Pressure anomalies to the north that have been absent for actual charts recently... that we scratched our heads at the lacking of....

well look who joined the party... finally

http://www._________/charts/gfs/euratl/charts/meanslp_anom_20181204_12_324.jpg?

edit: I take it WXcharts are liked on here?  Image wont post

Should be nice wandering round Edinburgh's Christmas Markets 😲

https://www.theweatheroutlook.com/twodata/chart.aspx?chart=///www.theweatheroutlook.com/charts/gfs/12_384_mslp850.png?cb=158

Note that the lows pictured are in the descendant (southwards) as the HAB asserts itself step, by painful step. Date wise and set up wise, I hear Bing Crosby crooning in the background.

(The easterly/ NEly pattern looks to be trying to set up earlier than this. The trouble is at the end of the run, the Atlantic depressions are scarce- and I don't actually go for that easily. More credible if they were there in true number, but disrupted somewhat).

Yes Neil, seems to be a recurring theme  Ecm holding firm so far.

ECM T+168 Scandi high, solid run again.

T+192 = bingo!! Sorry can’t post chart.