The ECMWF is going for a colder scenario and doesn't bring back the westerlies anywhere near as early as GFS

Simon Keeling has quite an interesting video on the comparisons of the two models over on weatherweb.net

http://www.weatherweb.net/wxwebtv2.php

Lol! To complicate things further remember that in practise raw ensemble probabilities are not considered reliable. For example, if 10 out of 20 show solution x you may think there is a 50% chance of this happening. The reality is this isn't the case and further calibration of the raw ensemble output may be done. 

GFS sure is persistent with the flatter jet scenario.

The problem here is that beyond about 5 days range, I have an instinct to attribute GFS and GFSP output that flattens the jet to its behavioural traits rather than a real clue as to how things may evolve, though I will never dismiss it unless there are serious data errors or something.

So I turn to UKMO and ECM, but only the latter covers the crucial period at the moment. JMA is often worth considering but tends to go off on a tangent for some reason. The same could be said for GEM, though I'm still seeing the old habit of developing low pressure as much as possible that it had before the recent update, at times with the excess amplification that super-intense storms sometimes lead to, at times just acting to steamroller the downstream pattern.

So far ECM, JMA and GEM have all been disagreeing with GFS one way or another, and showing more amplified solutions.

Arguing the other way is the fact that the stratospheric vortex doesn't look like breaking down to the extent predicted by most of the model runs of a few days ago. So it wouldn't be much of a shock if GFS turned out to be showing the way forward within the next 10 days at least.

With regards to the vortex, a strong mid-Atlantic ridge reaching up to the Arctic with the western flank across Greenland would at least serve to drive some strong wave breaking which would basically land a hammer blow on the metaphorical crotch of the vortex.

So given how unlikely a last minute turnaround has now become regarding the Scandi High being knocked down next week, it seems that all hope comes to rest upon getting the strongest, tallest and longest-lived mid-Atlantic ridge possible starting about 10-14 days from now.

It appears that we've been chasing some ghosts with regards to a cold outbreak hitting the UK during the first week of December. That follows a similar chase with respect to late November, though less of us were expecting anything much back then.

I'm primarily hoping for patterns which attack the strat. vortex during the first third of December, but have allowed myself to be tempted to chase a possible bonus shot of cold during that period as well. The silly season gets to us all some time or other!

Boring is the outlook if it's cold you are after. 

The Atlantic and the azores high battling it out as to witch will give us the next spell of boring mild weather

http://modeles.meteociel.fr/modeles/gens/run/gensnh-21-1-138.png?12 

Well today GFS is along with UKMO as for this Weekend and Next Week Forecast, Mild Weekend with SE to East flow Continental High, then Monday and to Midday Tuesday Atlantic Anticyclone and Just a fraction cooler, but it should turn cooler by Tuesday afternoon to Weds- Thurs and Friday but as the last 2 Weekdays are concerned the Milder Atlantic air should mix in with Deepened SE Greenland to Iceland PV Northernmost N Atlantic very windy Low Pressure with A big High over UK and stretched to Central North Atlantic so not very amazing weather pattern at all, the GFS and UKMO back this.

East Europe sees Cold Frosty High Pressure with A Cold Wintry Low over to the East NE of Finland over the Arctic Sea.

Also both GFS and the UKMO show a 1030-1035mb Arctic High pushing South off East NE of near Svalbard (Over Northern Norwegian Sea) Brr that is good for Sending Cold air to UK as each  North Atlantic East NE directed PV SE Greenland and Iceland Low the FI GFS pushes colder NW'ly airstream RPM air for December that will give us some cold frosty nights and clear winter sunshine.

😀✨ 

https://www.metcheck.com/UK/discussion.asp

I think this is well worth a read, suggests how poor the GFS is compared to it's parallel run. Just shows how much technology has come along and influenced meteorology.

Maybe this is the reason why we should take the gfs, and all the models, in fact, as a pinch of salt in FI

Warped perception?

I think GFS suffers from unfair criticism because it goes out to +360hrs
If you look at the 5 and 10 day verification stats, you would see there is little significant difference between the three major NWP outputs.

Quite right. Also I think many people don't realise the GFSP will be an incremental improvement not a revolutionary one! I've been running the GFSP on TWO for several weeks now and think the main benefit will be the higher resolution datasets providing more accurate short term forecasts for the Cornish peninsula and other coastal areas. The benefits in the day 4 to 16 range will be very marginal indeed, although the GEFS upgrade next year may help things more.

ECM looks pretty bland tonight. The 10 day polar projection doesn't fill me with excitement either. 

Unbelievable temperature contrast at +72hr in America; have you ever seen the -20 and +20 contours this close?

The GFS upgrade has just been pushed back from Jan 7th 2015 to mid January.

My view of GFS is a consequence of years of watching it correct towards a more amplified flow from a flatter one.

As for GFSP, that's largely based on how poorly it handled the sliding low we have coming along now, which admittedly could just be a rough rock on an otherwise smoother road of performance for all I know.

Anyway, ECM's joined the flat parade this evening so it seems more likely that GFS will turn out to be along the right lines. This is the problem I was talking about earlier - my instinct does sometimes leave me with more hope than is perhaps justified. Thankfully, the disagreement tends to resolve far enough out to prevent a major short term letdown 

It's not a given, but it increasingly looks as if we're not going to have any luck in the first third of December.

With the blocking to our east obliterated, we're left waiting for a weaker jet with an amplified ridge building towards high pressure in the Arctic that seems determined to keep coming back for the foreseeable.

With no sign of a persistent east U.S. trough to set up a strong thermal gradient and supercharge the Atlantic jet, we should see an opportunity come along sooner or later - last winter was truly exceptional in having none of that for two months straight (mid-Dec to mid-Feb).

Of course, with an increasing tendency for low heights over Scandinavia as the strat. vortex drifts or at least extends its influence that way (that much remains in place if nothing else), chilly polar maritime air masses should feature in our weather fairly often during the first third of December, and that, coupled with Atlantic ridges building into said air masses, may well produce below average temperatures overall. Nothing at all exciting to track if the pattern remains fairly flat, but not quite ordinary either.

Fact is though, we really could do with one of those Atlantic ridges dealing the strat. vortex a good blow. For that, a weakening of the Canadian polar vortex lobe would be mighty handy. Until then... might go into a slumber if tomorrow's runs are as flat as tonight's 

Is "upgrade" referring  the weather we will experience across the British Isles, or the forecast model from GFS?

fantastic post stormchaser,very detailed thanks for posting, 

Thanks ever so much James.

Thats a huge central belt from ecm looks rather odd indeed

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

That's a good point actually.

Shame to see the upgrade has been pushed back again though.

Malcolm
Wakefield & Gothenburg, SWE

Good Post as always SC. One thing I like about your postings as well as the detail is that you always explain how you think certain evolutions could, have or haven't developed as shown and this is most helpful at such times as when the cold only protagonists fill us all with detailed information on how cold weather is likely down the line then totally disappear when such charts either fail to materialise or are withdrawn. You don't do that and are a man after my own heart in that 'weather' is a 365 day a year hobby and not just a seasonal interest. Keep up your excellent work here I and many others really appreciate it even through what appears to some may be a period of quiet and benign Anticyclonic weather coming up soon.

No, the snow has been pushed back to Jan 2016 due to strat wave 3 breaking late, so the upgrade must be to the GFS model.