LRD

And here comes the northern blocking. It's probably a load of nonsense but this GFS run has turned out surprisingly entertaining

After a tepid start the GFS actually turns out ok! Thanks to the jet staying waaaay south. But without some northern blocking you'd think the jet would want to take it's usual Scottish winter holiday eventually Really interesting stuff though, whatever happens

Well, I'm certainly not emotionally invested in this and can look at it quite neutrally We have in one corner 4 GFS op runs in a row showing a very different outcome to what the teleconnections and other big picture stuff and the professionals are saying - and those ops say no real significant cold. There is some sort of support from GEM op runs In the other corner is basically everything else saying it will get cold You can't ignore 4 GFS op runs in a row but I am still confident of a cold, possibly disruptive week next week. If that doesn't happen then lots to learn teleconnections-wise and what a massive win for the GFS it would be. The mocking it gets on here would result in some humble pie being eaten!

Scott - got to challenge this. EC46 has been consistently showing a mild week 22 Jan. It's also been consistently showing colder potential after, too, which I've pointed out most evenings on here too. It's a model from the respected ECMWF and this is the model thread. It's funny that people are allowed to look miles in the future for cold but we're not allowed to look at what might happen after the cold (I was actually looking for signs that it might extend into the week of the 22nd) The irony is that I've been one of the most steadfast on this cold spell happening when others have panicked and given up at the slightest hint of things going wrong in the day-day runs!

It's a model mate and this is the model thread. Sorry if that offends Mate

Complete flip the following week, unfortunately And then the pressure anomaly is high in the vicinity of the UK but not in as promising places as it had been showing

The last frame on the ECM won't look like that come the time. It's just computers playing around with different scenarios in an overall cold pattern. But if it's longevity you want, then you want lows to stay well south of you

Agreed to an extent but it might be the only chance that some folk see snow. Still think there will be a battleground snow event somewhere in the UK but I'd favour south of the M4 as these lows tend to track more and more south over time

North - 6-9 hours of snow for many and then rain will wash it away for most.

MOGREPS for London. Good clustering below -5. Some stubborn warm members but they're becoming isolated

If that ECM run comes off at Day 10 (which it won't) you won't need snow shovels. The rain will wash the snow away by Day 11! But the cold might be back again shortly after

Not necessarily as early as the 19th though. My punt is for it to warm up at some point week of 22nd before more cold by early Feb

Hmmm, more like wellies Manchester south! It'll change though

Angle of attack looks wrong. Mild incoming but it's irrelevant at this stage

Yep. Those phrases are right up there (or down there depending on how you look at it) with 'downgrade', 'shortwave drama' and 'fraught with danger'

Pressure falling in Iberia and the Med too. Very important if it's cold you want

192 ECM. Good chart and this will probably trend south with time as these low pressure systems tend to do

Looks fine at 144 Except the bulge of heights just at the base of the retrogressing high into France.

The signal is for weaker heights up there but that doesn't necessarily mean cold won't win out. IIRC Dec 1981 never had huge pressure readings in Greenland. But there was enough high pressure to drive cold air to our latitude and keep the jet to the south with loads of battleground snow events and bitter overnight lows We sometimes overlook the good in search of the perfect on here (and in real life!)

Spot on Especially the bit I've bolded

No, not necessarily wrong and I made that point earlier in the thread. It's unlikely that it's right but you don't just dismiss 2 GFS op runs in succession

I think me and Luke are the only ones who like the UKMO 168 frame! The annoyance is that slither of heights that has appeared over France

That's what I was about to say. What a coup for GFS if it is proved right! And I can only imagine the meltdown on this thread if ECM shows similar at about 6.40 I don't think it's right by the way. Ensembles will tell us more

What cold spell? Asks GFS

Well that's 2 ops in a row from GFS so I think we'd be foolish to dismiss it completely. However, it's the underdog at the moment and I'm as confident as I've ever been that from Sunday/Monday we're into quite significant cold I'd be really interested in what info is being fed to the GFS that leads it to such a different solution to ICON and UKMO. Does their computer see a problem with the effectiveness of MJO for example?