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Impressive ECM op runs and more and more of its ens members have started trending that way I am surprised but I am still cautious as I think it's still easy for the ridge to end up much closer to the UK

I see what you mean, but the problem is that more and more members of the ECM ensemble push that ridge further south (over W.Europe), which means that essentially the ridge replaces the current cold trough. That together with the increasing solar insolation can result to a pretty warm setup (e.g. gfs06 op run, which was very warm for the UK). If anything the pattern might end up even flatter (with the ridge over France and Spain)

The pattern is retrogressing but not in a good way, the ensembles now have the mean trough west of Europe in the 240-360h window. I agree with your other comments, in fact the way the models are currently trending I'd put money in 20C being reached in early March

Irony is fine, but take a look at today's ensembles: the warming/retrogression trends continue and now the ECM ens mean shows at least normal temps from the 14th onwards. In fact it wouldn't surprise me if the models settle on a warm outlook in the next 48 hours. I am a cold & snow fan but I prefer to call it how I see it.

Not only I can't see anything really cold on the horizon, but I think the models might actually be picking up the first signs of a pattern change to much warmer conditions for the 2nd half of Feb Both GFS & ECM ensembles have been moving gradually warmer over the last 4-5 days with the cold European trough retrogressing

I think your assessment of both the MJO & the GWO are wrong and I think you had done the same mistake back in mid-Dec. The Pacific convection and the heat content near the dateline are currently both high as you say, but there are already strong signs that the Pacific convection is declining, while the Indian Ocean convection is taking over. That's why I think we are going to see a phase 2-3-4-5 circuit of the MJO during the rest of Feb and this is what most models have started showing. The GWO is always more difficult to predict as it involves extra-tropical features, but a low AAM state (phases 2-3) is easier IMO during the next 2-3 weeks. Overall these teleconnections suggest that a warm pattern for W.Europe is more likely than a cold one during 20Feb - 10Mar, while cold risks increase again in mid-March if the convection returns to the Pacific.

Great post and I hope you are right, but I think you might be underestimating the risk of tropical convection returning to the Indian Ocean in early Feb with the AAM tanking/ In fact and despite the favourable stratosphere, I think there is at least 50% chance of the MJO progressing into phases 3-4-5 by mid-Feb, which would give us another spell of ~zonal weather similar to late Dec and early Jan.

and why would that move of the vortex be good for us unlike the move in December?

I see what you and bluearmy mean, but if you go to 384hours, ~15 out of 21 ensemble members have a trough southwest of the UK, which is a bit surprising: http://www.meteociel...&mode=1&ech=384 For me with the latest models, the chance of cold weather before 18 Jan looks <40%, but it's probably >50% during 20-30 Jan due to the SSW and the potential dateline convection.

Sorry but I don't think it's vague at all, at 340-384h it shows a weak -NAO/AO pattern but with a big long-wave trough in the Atlantic (west of UK/France) keeping the cold air in Scandi and Russia. ECM ensemble has also trended in that direction today. They both also show more record breaking warmth for the East coast of the US with a trough/ridge pattern for them (Dec was exceptionally warm there). I am not saying these ensembles will be right, but it's not fair to call them vague. To me it looks that until/unless the MJO moves into phase 7, the hunt for cold might continue for quite some time

ECM ensemble is a horror show, it moves against its op run and it now has above normal temps throughout next week

ECM ensemble mean has the same pattern persisting from 180 to 360h! Ridge in W.Russia, another ridge near the Hudson Bay and a permanent trough over the UK Very wet with normal to cool temps is a fair description for it. At least it shows the 12z op to be a warm outlier next week and also slowly heights are rising in the Atlantic towards Xmas

ECM is quite poor tonight for cold weather, in fact next week it's very warm for the whole of W.Europe

After struggling with it, this EC run doesn't really bring the cold pool into the UK and has the Atlantic trying to move in at the end, but who can trust it so far out... I expect a slightly better EC ensemble tonight Worth also mentioning that this run has some extremely low temps in France and Benelux during Sun-Tue above the snowfields, surface temps there come close to Feb last year!

I can't sorry (work link) - It's mainly over Kent but most areas southeast of London get a slight dusting on this run

ECM gives 2-5cm of widespread snow in the SE on Friday afternoon (and much more on the near Continent) The rest of the run should be good too

Many keep saying that there is still time for changes and it's true, but most of the model changes so far this week are poor for cold weather. We seem to have confirmation of a cold variable pattern, a fair amount of high latitude blocking but not of the right intensity and location, which leaves us with plenty of potential. Could most of Dec go on like this with some great FI setups which never materialise?

Thanks for that, well argued and presented forecast. Good luck!

The end of this ECM run is quite decent but again filled with the same issues: no strong high latitude blocking and plenty of mobility in the Atlantic. I guess it could be described as a cold variable pattern, much better obviously from zonal setups but nothing to get really excited about.

The whole of the UK is in mild air and westerly flow at 168h on this run It could be short lived though

ECM is further east at 120h with lower heights south of Greenland It will probably be faster to warm up compared to its 00z run and a fairly long way from the UKMO

This chart might now show a zonal setup but it's not particularly cold either. The pattern to the west of the UK is quite flat/mobile (green lines)

that's the problem with relying too much on mean charts far out, they can still change suddenly. In fact, the trend since last Tue/Wed has been for a weaker ridge to our west. The ridge we are going to get later this week is much weaker and less expnasive than what the ensembles and the NOAA charts were showing during most of last week

very good run so far our ridge is getting very squeezed at 156h and we need the new trough to disrupt again. That's the problem with a much flatter N.American pattern we need all these troughs passing south of Greenland to disrupt and re-enforce our blocking high, if any of them goes through east then the cold spell soon ends

Still early but it looks like this run will disrupt the trough again so it won't follow the ECM I'd give a 65% prob of ECM flipping back tomorrow morning