That is a big shift since this time yesterday on the GEFS. I've been monitoring the date that the mean 850 rises back above -5C for London in all of the runs. For most of the time it has been between Feb 11 to 13 but is now pushed right out to Feb 17. Admittedly there are still several mild options from Feb 13 onwards. Other models giving other outcomes too so extended severe cold is not in the bag yet by any means. 

Could be something from the NE 

Could be good 

Control is better than Op

Worth noting that GEM was awful again. Should be taken seriously as it predicted this spell first

Feels like Feb 1986. Cold but largely dry after the initial snow. I remember here, the snow stayed on the ground nearly all month. My snowman lived longer than any previous and any since. 

Total opposite to GEM with energy undercutting. Lets hope this is the right solution

just noticed that GEM control run totallly different to the op, so that is good

Does anybody know why the showers in the north form well out at sea before moving inland whereas over East Anglia they don't appear till they hit the coast or grow inland? Seems quite a sharp dividing line between the two.

Remember the wise old words of TVS weather forecaster Trevor Baker 

about Scandi Blocks "If it last for 7 will go on til 14, if it lasts til 14 goes on til 21....

Remenants of frontal system limiting height of convection. Orography generates shallow lift/convergence.

JFF and deepest of FI 

I'm liking your more cautious commentary Marcus 

Is that a genuine effect? I thought it was just the range of the radar 

Me too 

I’m really enjoying model watching at the moment (not as much as lamplight watching on a snowy night but that’s for another thread)

GEFS0z has an increasing number of members indicating continuation of decent cold into the longer term, low precipitation indicates the scandi high being highly influential to our weather to me.  The members touching -15 don’t look as alone as they did a few days ago.

ECM ensemble also shows the UK between a scandi high and mid North Atlantic low pressure. It’s very interesting to see how this plays out and if we have any slider lows for that setup. 

I can’t help but smile ear to ear when I see the FI GFS 0z operational. That channel low is a sight to behold. I can’t help myself! Mustn’t get excited about that just yet

Is the radar coverage less off East Anglia then? The structure of the streamers is completely different as well. Weaker and more diffuse. Those above the line are distinct clumps and more intense. I think I favour Quantum's explanation unless someone knows different.

The one true ring. My precious....

Just posted about the similarities in my FB group. I was encouraged by the commentary on the CF forecast last evening