Pfft, I am the 0.01%!

The 12z GFS does indeed manage to bring SW'lies back but interestingly it's not as quick as this morning's runs - it's at 252, two days later than the 24th. The 24th is worth mentioning as the 0z and 6z GEFS, as well as EPS all showed warmer air moving in by then.

Looks very wet in a week.... only a day or so ago, the consensus seemed to be the although the easterly was dead, we'd have a dry and settled January... When you consider how much the model output has changed over the past week....  from no easterly, to easterly brewing, to dry and settled  until month end, to wet and windy within a week now, it's clear that the model output is all over the place, and anyone confidently calling the weather after +120 is a fool!

No offence Darren

Very different to previous runs, my guess and it is a guess, the LP will be gone on the 18z and be missing from the ECM

Oh, none taken - I found it funny!

The ensembles are trickling out now and even at 102 it's far from certain... some members have a chilly easterly while others have a calm day under a high. That's for here, mind you, other areas may vary.

http://modeles7.meteociel.fr/modeles/gens/runs/2017011512/gensnh-11-1-228.png

I'll take this one!

A lot of uncertainty from next weekend

Yes, that LP looks like a very specific combination of an innocuous secondary low that forms off the static LP off Newfoundland which happens to engage with a portion of the jetstream as it approaches the SW Peninsula.  As you say, more likely than not to disappear in the next run.

Wise words. The output is as volatile as I have seen it. It's impossible to even guess what the charts will be showing in a week at the moment. 

Subtle differences and markedly different conditions can be garnered from looking at the 72-96-120 hour and to 144hrs. 

UKMO is less chilly with 1035 to 1030 mbs Europe UK West Central to NW and Mid N Europe High.  

Chilly or cold GFS 12z which has Europe seeing coldish days and frosty nights, with chance of very dry weather very high indeed and chilly cloudy days for the UK.

At 120-144 and greater divergence between the two, and it looks like NAVGEM is in between them both on it's 00z run.

The ECMWF 00z run looks similar to the UKMO with Stubborn hard to Mid Latitude High in W and Central to N Europe.

All three show North and NE Norwegian Sea and NW N Russia far NE Europe on the colder side, and next 3 days GFS keeps the East and SE Central Europe keep the cold Continental Polar Arctic Air getting some modification over West and NW UK as Low Pressure in Mid N Atlantic pushes to Southeast off Greenland  and by Friday to Sunday in part tracks NE to SW Norwegian Sea from South and SE Iceland after passing off S and SE Greenland on the ECMWF NAVGEM and UKMO, the GFS splits it and shows the same pattern but keeps the cut off Low and push that across us from Mid SE of N Atlantic that would be bring rain by late Sunday into Monday as the air is not cold enough for snow unless cold air under the West NW Europe High together with Cold SE winds embeds cold air ahead of it on approach😁. Smile.

Will the cold airmass over Mediterranean stay away from NW EUROPE - the GFS brings the cold dry frosty nights and cold days back in by Midweek and have Cut off Low aim to affect UK by next weekend or the Monday to Tuesday following it...

Chance of freezing fog also quite a possibility ahem😀.

It could get colder from Friday to Sunday, with a return midweek in third week of this month of mild SW flow and Mid N Atlantic to UK spells of wet and breezy SW and West flows. 

🌧🌤☁️🌫🌞🙂.

Hello - where did this low pressure come from?

Yes - also the low pressure is over the south and the south should be drier and colder not milder and wetter as next Sunda.Monday is forecasted on models.

http://www.meteociel.fr/modeles/ecmwf/runs/2017011512/ECH1-120.GIF?15-0

ECM so far. Similar to UKMO

http://www.meteociel.fr/modeles/ecmwf/runs/2017011512/ECH1-168.GIF?15-0

high sinking. Consistent from ECM

Looks like low pressure moving in during FI on the ECM 12z, I guess at least it will,provide some actual weather! Quite a bit different to the previous run by day 8 and also generally different to the GFS from early on. No wonder the professionals have had highlighted the uncertainty at quite an early timescale.

http://meteociel.fr/modeles/ecmwf/runs/2017011512/ECH1-192.GIF?15-0 

looks like its going to be a long wait for the next cold spell if it comes at all, perhaps we will need the strat warming to help us but the clock is ticking on deep cold.

If ECM verifies we will be looking at mid Feb before anything is possible and getting too late by then

When the weather turned zonal and in some places stormy during the week leading up to Christmas, a few people here assumed that pattern would continue well into January. In the end, it only lasted about a week.

So far this season, any unsettled spells seem to have been relatively brief affairs, and until there is cross-model agreement on one particular set-up developing within the semi-reliable timeframe, we can't be sure what we are going to have later on in January let alone how long any particular type of weather may last for.

I assume the difference between ECM an GFS at 144 is how they handle the jet strength and positioning?

At 120 they're near enough identical.

At 144 they diverge with GFS tracking the jet south so we don't end up with a big slug o' HP to our South, whereas ECM (I think judging by how it evolves anyway) pushes the jet North, the HP joins up and the jet happily carries on chugging away to our North thereafter.

Be interesting to see which one has modelled that best over the next day or so (assuming both of them don't change their minds by then).

Edit: More amplification by ECM at T216 I see, possible NW'ly setting in after. Bit different again, kind of highlights the uncertainty at the mo.