Totally agree just shows how things are nowhere near settled! Think you would be buried if that run came to fruition! Fun to see

https://www.theweatheroutlook.com/charts/gfs/12_219_mslp850.png 

Here's the xc version of the GFS op IMBY. Frankly I can't think of a worse day of weather at this time of year.

https://ukwct.org.uk/weather/xc.jpg 

I wouldn't claim to be any great shakes at chart analysis but if there's one thing I've learned is that a cold spell is very, very unlikely without cross model agreement and consistency. I don't think we have either yet. So while I won't write off our chances of cold when charts like that are on show, I won't be getting out my thermals just yet. Still, there's enough there to have me keeping an eye on the charts at least. 

In general terms I'd say the mid and long term outlook remains 'uncertain', with small changes having relatively large impacts for the UK. The earlier ens sets for close to MBY (London) had a roughly equal split between members having 2-3 days of cold air and then going mild and those keeping it colder at 850 level for 3-4 more days. I suspect the 12z set will be similar.

As Darren and others have mentioned of more immediate interest/concern is the LP crossing the country on the 1st Jan - could be some damaging winds around if the output stays as it is. 

It's certainly not looking 'boring' and does continue what so far has been a mixed winter, with HP spells mixed with vigorous but mostly short lived LP interludes. 

Haha, what was I saying just this morning about the amount of volatility in the output!

I think it is going to be another couple of days at least before the models get fully to grips with happens beyond the middle of next week, which is still firmly in FI territory at the moment.

And there is certainly a cluster supporting a colder evolution

All forgiven by t+252??

😉😆

I personally like the 12z. MBY isn't one of the most favoured spots, but would get 2/3 decentish falls over the course of a few days. A fortnight late, but these days any fall is a bonus.

https://acd-ext.gsfc.nasa.gov/Data_services/met/qbo/qbo.html 

Not really, as that's way too far out for any reliability, and even then - 6 hours of sleety stuff followed by more rain isn't exactly exciting. 🙂

I'm still hopeful the 12z GFS marks the worst point of the winds forecast for down here. A nice shallow low as per the 12z GEFS control would be a win all round, I think!

Absolutely, unless there is cross-model agreement then there is absolutely no chance of a cold spell and even if there is it's still been known to go wrong. I've never known the opposite to happen and a surprise cold spell to appear without cross-model agreement.

The part in bold is blatantly untrue. That aside, there is reasonable agreement this evening but not compared with the previous set of runs. For that reason alone the nex t set of runs may show a different scenario.

This evening’s output is a shift in the colder direction in the same way as yesterday’s was a shift towards the cold, so I wouldn’t jump to any conclusions just yet, beyond the fact it looks very likely to be unsettled at the beginning of next week.

Yes, the timing is slightly different but the overall pattern is not.

That top left corner of the UK could end up being a different world to the rest of us this time next week.

Altnahara is going to be like the Canadian Tundra. Orkney looks like its going to get hammered to. The sort of remote parts of NW scotland could easily become cut off.

https://www.meteociel.fr/cartes_obs/gens_display.php?x=288&y=106&run=12&runpara=0&type=3&ext=1 

If its still showing something similar in a weeks time I'll take note. Its not the first time I've seen phantom cold spells in the ENS at this time of the year 😉

Be interesting if they perform with any credibility next week or so.

https://www.theweatheroutlook.com/premium/gefs-tables.aspx?run=06&fv=tmp2max&loc=london&lat=51.5&lon=0&p=&cty= 

https://www.theweatheroutlook.com/premium/gefs-tables.aspx?run=12&fv=tmp2max&loc=london&lat=51.5&lon=0&p=&cty= 

Obviously it hasn't happened yet but if we get a significant cold spell. It's a big win for the robots. Sensational 12s all round tonight. 

UKMO looks to be fly in the ointment for cold weather fans. Still to get the big 3 in agreement at the same time.