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means can be deceiving but it has to be said that ECM ensemble mean is pretty poor at 192h http://www.wetterzentrale.de/pics/Reem1921.html

Unfortunately EC ensemble is making a significant move towards its op run with 40-50% of its members backing up more energy passing though eastwards. The mean obviously will still show the op as a warm/flat outlier but it will have a much flatter pattern It's still al up for grabs and at these time ranges op runs are more important anyway so here's to a very different EC run tomorrow morning!

Thanks for the reasonable analysis, but I think you were wrong to say this: "In my view this pattern will undergo minor changes from time to time but there is NO sign of any genuinely mild air making into the UK for at least 2 weeks from the middle of this week, who knows it could be longer!" Even if you wrote this before tonight's 12z runs, a 'small chance or unlikely to go mild' would be more appropriate. And since I keep reading in this thread that the teleconnections are great for cold, they aren't exacly great: we got an impressive westerly wind burst at the equator near 160E (always good for downstream amplification) and a very good AAM spike, but there's been a lot of interference from other areas which has prevented a nice MJO phase 6-7-8 circuit. This meant a more zonal setup over N.America which can put pressure on our block (e.g. tonight's EC run) and it also meant that the N.Atlantic ridge is not that strong. The AAM is likely to fall now in the next 2-3 weeks and we'll probably get tropical convection returning over the Indian Ocean in mid-Dec (phases 2-3 of the MJO), which is not a geat setup for high latitude blocking. That can still happen though if the base state still favours it.

EC is poor already from 72-96h as it doesn't send enough energy southeastwards underneath the block. Even then it's so easy to go either way but this will be a 'warm' run esp for the UK, where it might even go mild. Even the UKMO which looks great at 144h could still g wrong after this as the high is weak and enough energy could spill westwards (e.g. BOM). It could all be a wobble and tomorrow EC could be much better again, but what I don't agree with various posters is that we shouldn't look at 'rogue' op runs but focus more on the ensemble and the 'large scale'. At these time scales (<180h) and when small shortwaves can play a big role, op runs are equally important and can often pick up a trend first and the ensembles can be as fickle and change suddenly. Anyway here's to EC being a random wobble tonight

Still goes cold from Thu though so it's more of a delay but delays are rarely good

Another non-cold EC op run unfortunately, this one actually has above normal temps for next week despite the blocking I suspect the 00z ensemble from EC will also make a move but still plenty of time for EC to flip back to colder solutions

Excellent EC ensemble tonight with very good consistency The N.Atlantic ridge remains very strong all the way to +360h with the NAO index approaching 2 sigma negative in early Dec and the strato becoming more & more disturbed hopefully some impressive op runs tomorrow

It's called cold advection and you can go from 12C on one day to snow on the next one... in this run the cold advection takes place in the wrong places and because of the shape of the trough there is sifnificant warm advection over France & Germany, which affects our air mass as well

hi there, the pattern change and the beatiful blocking high are almost done (and it was a brilliant call by GP), but the cold weather is far from done yet. Anyway, it's just one run and it could all change tomorrow and we shouldn't forget that unlike gfs the EC ensemble is rock solid for early Dec

I am sorry, but that's not the case. Even now both us and the continent can become very cold very quickly and we don't need cold pooling to our east. This run mixes in a lot of warm air from the Med, London & Paris are 4-5C warmer on average next week compared to the previous run, which was quite cold.

This EC run wouldn't give cold conditions in any month, the air mass at the surface is not cold at all and it's actually quite warm for most of the near continent. Also the way this run ends doesn't guarantee that cold air would come eventually as we end up with a trough southwest of the UK I wonder if all this is happening due to a much faster MJO progression, most models now predict convection over the Indian Ocean around the turn of the month, while until now we were supposed to get a nice, high amplitude phase 8 for early Dec. More runs needed obviously but a very worrying EC12 run

Latest EC run is quite worrying actually, the blocking high near Iceland might look nice & impressive but most of the cold air is wasted/missed and the temps look around normal for England. Its previous run and the latest gfs op run are much better for cold next week.