The GFS and ECM ensemble means have always indicated that towards the end of the first week of February was a much more likely time for the onset of serious cold than the 1st or 2nd of the month.

If we didn’t have such a strong jet we could indeed benefit from the continental freeze. As it is we’re left bathing in relatively mild Atlantic air. Such as it is and these days ever will be it seems. 

The thing I don't understand is that supposedly global warming is making the jet WEAKER, and  that is often blamed for allowing these cold outbreaks further south in the USA: the idea is that a weaker and more meandering jet stream allows cold air to leak further south out of the Arctic. But over here it seems to have the opposite effect - the cold air in America fires up the jet and makes it stronger. Is anyone aware of any studies of the changing strength of the jet in different parts of the northern hemisphere?

Given that the Arctic has warmed by more than temperate latitudes, thus reducing the temperature differential, it does intuitively seem like that ought to make the jet weaker.

I mean the chance of a properly cold Easterly around 1 February of sub -10c 850s which was shown on the GFS operational runs yesterday and had support of around 30% in the GEFS but now seems to be non-existant today. I wasn't saying it was likely just that it had a reasonable chance yesterday but now seems to be no chance of it today.

And I'm by no means the only that is frustrated by the Winter and the missed chances given the potential we have had with this pattern and the cold air present in Europe. You might like to be the eternal optimist and see everything in perspective but I can't really see anything that positive for cold weather fans in the output at the moment other than more frustrating near misses and cold rain for most, but hopefully we can still get something more interesting.

I don't think that's an objective assessment. A nationwide cold snap / spell remains a possibility as we head into February. Whether or not it is likely is a different discussion.

Optimism has nothing to do with it whatsoever. Given the ensembles for the start of February are as cold (and possibly slightly colder) on the most recent sets than they were on yesterday’s 12z sets I find it surprising that you think there was a reasonable chance of cold then but none now and base that on an operational run. I have already stated that the 06z GEFS has 10 runs at or below -10°C (for London). It all just seems strange and counterintuitive. There was a chance (no more than that) yesterday and that has not changed today.

I mean the GFS 12z op is showing -10°C air (t850hPa) here around that time period, I don’t think in isolation that makes it more likely once again, unless it is backed up by the ensembles and subsequent runs. Recent experience suggests that may be unlikely.

There's no blow torch being shown and we haven't had that at all this winter 

Since mid December,  it's been average or chilly

The 12z has a strong block in place,  Atlantic is held with us sat in the middle 

No sign of cold though 

Very average 

I think the Atlantic jet is becoming weaker overall. Strong jets occurred in 1947 for example, but penetrated further south into southern Europe allowing those bitter easterlies in. The jet these days seems much weaker and placed much further north on average. 

Are we looking at the same GFS run?

Cold in Scotland (okay probably more grim stuff for some but cold uppers anyway!):-

Chilly to cold over most of the UK. That would be cold at the surface away from far SW I think.

Cold air in situ over a chunk of the UK, rain turning to snow as LP pushes precip North and convective snow for some eastern coasts:-

Weakish (i.e no yellows on the 500hPa charts, so surface stuff I believe?) but extensive northern blocking starts to push colder air south:-

Cold air pushing south meets LP moving in, heavy snow for some:-

Now how likely that is, is entirely reasonable to ponder. It does though continue the theme of HP reasserting itself to our east in the near to mid term and then northern blocking becoming more influential thereafter. I imagine it'll be part of a colder cluster in the ens, with plenty of milder options. I wonder if the extended ECM will continue with the northern blocking too, as it's consistently shown for the past couple of runs - there's milder ens members in that suite too so very much not a guarantee but I'll go with it will have a similar pattern, whether it's enough for colder stuff, very much TBC.

It's entirely possible the whole of the UK could end up in a no mans land for cold in the currently modelled setup but objectively it's not what the 12z GFS op showed, which was at various times a wintry run (not for MBY really, although the rain would be colder at times 🤡). Unless the GEFS and ECM/ECM Ens backtrack there is a decent signal for colder weather around 7th Feb or so that IMO is worth keeping an eye on but noting the usual caveats:-

* It's deep FI. 

* It's by no means the only option.

* It's not a clean cold solution and much as the current setup all it takes is the jet to be stronger and/or a bit further north and things end up close but no cigar or collapsing entirely. 

As with the last possible cold spell until we are at the edge of the reliable (T120 ish) and the ens suites are solidly backing a cold solution I'll view any colder weather as possible but not guaranteed and try not to get carried away by charts like the GFS 12z op (or preferably better!), which showed a fair bit of cold weather around at times. 

2012 was a cold February in the S.E with quite deep snow for a week, at least it was here. In fact it was our best cold spell apart from the Beast.

I think the last time to have a jet that far south was in 1996/97 winter when i was in Toronto for Xmas and early Jan before returning back here was 9C mild, drizzly from the East.  I saw the charts on Canadian weather map show the flow from Russia, Europe, UK, Atlantic to Canada.  I don't see this over 6000 miles of straight easterly flow since that time.

https://www.wetterzentrale.de/en/show_diagrams.php?geoid=48656&model=gfs&var=201&run=12&lid=ENS&bw=1

 Now a little drop to -4c on the orginally 1st or 2nd Feb as a date stamp to start the deep cold so hope further runs to lower down to -12C required to prevent less cold temperatures and cold rain in early Feb.  -10C or -9C will deliver less cold and cold rain under this global warming threshold now.  I just wish we can get -15C to -20C uppers in the Uk to experience it that USA got many times lately.

ECM extended appears to continue with weak northern blocking albeit fails to get cold air south that much, so wintriness is mostly further north (will have a proper look when it's out on TWO).   

I didn't really look at the earlier GFS ops re US cold but the 12z is suggesting further deep cold shots, so might explain the less cold ens suite albeit the jet doesn't look to be overly active in FI versus current position. 

I think the climate of the Great Lakes would suit you much better, Jires! 

The US (or at least parts of it) is always going to see ample snow and cold temps every winter. But the UK (and Ireland) can do just as well with regards great blizzards, but it is just that the synoptics rarely fall into place, and increasingly less so over the last few decades. But we had 'the beast' to remind us that it can still happen, even if that is almost 10 years ago now. 

Very close in terms of distance and shape of the features. 

GFS OP at 240 blows the low up and give far north of Scotland quite a wild time of it! 

Further south and it could be quite a severe spell for some

By Friday next week - if it’s still showing sub -10 air over EA and a dump of snow, I’ll be excited. I think this time it will be. 

We need at least -12C threshold air to get subzero max temps and to get excited as well.  That why I want the mean on ensembles to drop it asap to -12 for here and lower for EA and SE due to nearer to continent.  Not happy with the 0z mean stubborn to drop as showing -4 while around 5 members went for -10 to -15C on that landing date 1st Feb onward. Today is 26th so just 5 days left so sooner than later the mean need a brute force drop it down so later today runs reflect this. 

Today is crucial. After dropping those very cold runs yesterday it seems like they are back around start of February. 

As you say mean / Op run not interested, but for once wouldnt it be nice for the suite to flip the other way and short notice like it always seem to do for mild.