The set-up that the GFS shows is always fascinating, perhaps data issues with it being Christmas time ? 

The GFS12z is missing some data today but whether that has an impact or not is always hotly debated. 

Perhaps not.  Enjoy the output.

Cold weather finally gets here , be an amazing turnaround if this verified ,  seeing as Shropshire is so dosappointed with the mild weather Im very surprised he isnt ramping this up

 Gfs P got pretty close to snow feast earlier today so we cant discount this sort of setup  just yet it does seem strange that gm has dropped it

Someone go get Darren

Spoilsport!

Actually, just to get things into perspective, it's worth remembering that ALL models have missing data at T+0 because there are more datapoints than actual data, hence the extensive use of ensembles to test how robust the evolution may be.

Anyway, missing data should be as likely to throw up any number of synoptic patterns offering a complete spread of options for our tiny speck on the global stage;  because it delivers up a Scandi block cannot of itself mean it's wrong or due to some missing data?

Anyway, back to the GFS 12z; the block doesn't quite deliver this time but is this a trend towards a westerly drift of the battleground or a blip?

Hi Peter,

Going back to the issues about possible missing data, I had thought this was more likely to be the case on holidays such as tomorrow, Boxing Day and New Year's Day. Today is a normal working day as far as I know.

I can quite clearly remember following the model output and this thread during Xmas 2012, when we had a very similar weather pattern to what we have currently. There were a few model operational runs during that time which showed a change to something colder and drier in early Jan 2013, and some people were saying "Don't trust these runs; there is likely to be data missing because it's Xmas". At the time I shared the same concerns, but once the festive season had passed and the models persisted with showing a change, I was more confident that something was afoot. I can't honestly remember what the MetO's thoughts were at that time though for the start of 2013.

Good to see you posting Peter 

Today's GFS12z is missing some radiosonde upper air data but I've seen this happen quite frequently through the course of the year. IMO this doesn't demonstrably make much difference to the output and accuracy. The thing to do is look at the GEFS12z postage stamps and see whether the synoptic patterns are broadly similar to the 6z set. 

So the GFS is faulty like YD used to say.

Perhaps a few more Brian than last night at 144

http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=1&ech=144

OK this is interesting, please let this be a trend 

Control also hinting at an Easterly ..............doesn't quite make it this time

roughly 6 out of 20 GEFS have the same evolution as the Op on the 12z.  All eyes on ECM now!

London short ensembles 12z...

Agreed...

So not worth thinking about the missing data drama some go on about every Boxing Day. 

Agreed, around 33%.  A growing trend? Makes for a bit of festive fun and makes a change from Bartletization and record highs, even if its all just FI musings.

EDIT Met O 144 ...ouch...

Just seen the GFS and did not expect that at all can the ECM join the Christmas party?

Think he got banned a couple of years ago for some reason shame as was a TWO legend . Speaking of TWO legends what ever happened to Matty H?

That puts the cat among the pigeons. Happy Xmas!

Okay so basically we have about a 20% probability of this actually coming off. Not a lot to hope for, but better odds than we have been used to seeing! Anyway I'm sure with the continued erosion of the polar vortex, more opportunities like this will come along even if it doesn't work out this time.