I believes it uses the IFS so there could some commonalities in the output. We'll see shortly, up to 72 at the time of posting.

https://www.theweatheroutlook.com/twodata/ecmwf.aspx

Just been scanning through the GFS ens from T96 or so and the creeping disagreement starts not far from then, with a lot of disagreement just a few days later.

Don't think I'll be counting any cold chickens for a while yet - need to see much better grouping plus agreement on the pattern.

I still think a cold spell is more likely than not at this stage but it's still FI where the countrywide good stuff is lurking (appreciate the North is always at more risk of snow with less chance of milder air here).

If the models are holding firm on a cold spell by Monday morning and there's good agreement of the pattern in the ens then great, but before then I'll avoid too much ramping/anticipation I think

Edit: I could be wrong but pretty sure GFS ens were doing this in the run up to the Feb/March easterly - growing agreement in the ens until 8-10 days away then a couple of days of still good runs but a fair bit of scatter before they tightened back up. Hopefully they'll do the same this time round

That 500 mb chart doesn't really tell you how cold it will be in the bottom few thousand feet of the atmosphere, which is what we are interested in. When we talk about "uppers", we normally are thinking in terms of the 850 mb chart.

As I suspected, the snow rows for Brighton are down a little, and Tuesday looks less sure.  17/23 down from 22/23

The US storm handling is of paramount importance- let’s see how the weekends runs handle things before getting too excited

Wise words, we've been here before, haven't we? 

Fingers crossed things remain rock solid tomorrow

Just following up my earlier post. Someone has to flag up the issues...

That European low that we worried was going to be virtually nothing for the weekend of 26/27th Jan earlier this week, is now modelled as a 985mb monster somewhere over or south of Poland on the GFS Op, Para AND Control. UKMet suggests something similar - remarkable model agreement at this range.

This makes for great looking synoptics but has the effect of drawing warm air up from eastern North Africa and over the Black Sea. The effect thereafter (not shown by Met as out of range but on GFS) is to sharpen the trough running north from the Euro monster low, and tighten the gradient, pulling the deeper cold from Scandinavia southward, instead of westward towards us. The broad scale cold pattern is there, and looks like it will be long lived, but - and I haven’t had time yet to check - I think that’s ultimately why much of the GEFS suite - even with its diverging actual synoptics - is more marginal for 850s during the second half of the runs than we were expecting.

Jeff

Yep, I remember 2009? When we had a single mild straggler on an otherwise rock solid ensemble...   and boom - it won the day.

I'm not sure where to find historic ensemble plots...   otherwise I'd share it. 

ECM throwing in a wobble at 120.

Edit... squeaks through at 144 but it's a close call.

Jeff

The ECM seems very consistent with this morning’s run at the 5-6 day time period. The trend continues.

I realise there is a 12hr difference in the charts but overall the pattern is very consistent 

The 00z ECM at 144hr

The 12z ECM at 144hr

A good question, especially once you see the 168Z chart...     

ECM very poor compared to what it could have been. As is so often the case, a stellar chart is worse than useless at a range of 144 or more.

I await the 0z runs before casting judgement on the overall prognosis.  All looking very uncertain and fragile for deep cold for the majority IMO.

Yes it will be cold, but with snow on the ground for most folk and the odd ice day? - very uncertain.

Is this what they mean when the say it's going 'Pete Tong'?

ECM isn't on board.

Its probably going to end up being right.

Jeff

Followed by another wobble of sorts!!

A little melodramatic if I may be so bold. It’s as likely to be right as the previous iteration was wrong.

No NWP is ever going to be tightly consistent within the ensemble envelope and inter run variability is to be expected. Are we not all agreed that 120 on is FI?

Looks a right mess 

And uppers look poor