GFS is far from mild infact it is a cold run with snow possibilities from a NWly

Temps from GFS 12z

5c , 1c , 0c , 0c, 1c , 0c, 1c , 2c , 2c , 2c , 4c , 2c ,2c , 1c , 1c

yes its GFS and it didn't exactly get the LP right but its worth a comment

Happy Christmas everybody ! 

Disappointing runs today, however, the block appears to be disposed of into the continent with generic ease. Caution is required.

Don't be at all surprised to see this little shortwave  over Denmark offering some hope of a height rises over Scandinavia after its moved away. 

More twists and turns to come before its good night Vienna 

Steve

Bit puzzled you have posted a chart from the GFS run and then said goodnight ??????????????????

It is a chilly run and no doubt wintry at times , with low single digit temps throughout

Yes , Yes FI is always at 120 but the run if verified cant be sniffed at

Yep, it doesn't look an overly mild run to me Marcus. Certainly not any more so that the vast majority of runs we have seen from the models throughout this month.

Hi Marcus.

Basically what I am trying to say is that the shortwave over Denmark needs watching. Don't be at all surprised to see the easterly back soon. 

I wouldn't complain , so much more interest this year than last, so not too bad at all

Well, that's some comfort perhaps.

Observation data has the highest impact at t+6 hours (end of assimilation period) and that gradually falls as the run progresses, so in theory it's the short-term output that is less trustworthy than usual.

Whether we see a backtrack towards more of an easterly influence next week or not, there are other interesting things going on in the output. First, there are signs of weak disturbances in the northerly flow on Sunday that could at least bring periods of snow showers (in fact the Met Office have a wavy occluded front - cloudy with sporadic snow?).

Second, we see signals for the PV to start travelling out of Canada before it's even had a chance to settle down, which suggests that we're unlikely to lock into a bog-standard +ve NAO pattern, with that as more of a transition period after which the pattern re-amplifies as the strat. developments start to show their worth. I think the GFS 12z later FI is a fairly good attempt at representing this pattern. The GFSP 12z is going along alright until the final few days, when a huge storm bombs out toward Canada for no good reason - just a fluke of the model I suspect (it has produced a huge number of bombing lows in lower-res these past two months, which generally never verify, though it wasn't too far off with the huge storm to our NW earlier this month).

Certainly the sort of situation where any downgrades in the jet strength could significantly reduce the period spent with a flatter pattern. A lot of changes needed for the westerly burst to undercut our mid-latitude high though... that was the best possible route to take us toward the period of strat.-driven polar vortex disruption a little way into January, but it appears that yet again we just aren't lucky enough.

Unless those data shortages are having a serious impact on the modelling of the ridge across Scandinavia, that is... cast your bets 

It is a possibility that it would be unwise to completely dismiss at this stage, and with a data shortage.

The odds favour the sinking high but there is a chance of an extended easterly and I too have been eyeing that shortwave.  An adjustment of the high NW by 200 miles or so would be sufficient.

As others have identified, there are also fronts and disturbances in the flow on 28th which could produce snow pretty much anywhere.

Get the cold air in, then worry about the snow.

Interesting times and Merry Christmas and goodnight!!

Sorry mods I couldn't resist!

It's goodnight from him and it's goodnight from me. Goodnight! (And Merry Christmas to one and all).

I've thrown this one onto the NW site, has caused a bit of chat , not too sure many follow the idea though

That's fraternizing with the other place! 

Anyway my view is that there is still time for things to change.

As the high is squashed the standdev massively goes up, most of this is due to normal chaos theory, granted, but I think we arn't at the point where this is certain quite yet.

Still perhaps 10% are going for the turnover scenario.

Also the uncertainty surrounding this trough is HUGE, I cannot emphasise this enough, the models are never going to be able to deal with this, let's wait until the low has passed and we have more data and see what happens. Hell I still have no idea where the northern extent of that snow is likely to be!

heights further west on this run, expect superior outcome.

Has anyone noticed the low developing in the N sea at about 72 hours has become stronger and stronger with each run (just like our domestic low has become weaker and weaker). If this trend continues it could impact our high (in a good way). 

Thanks! 

The 18Z was indeed a superior run, although probably not what people are hoping for, it is definitely a step in the right direction. 

The NAVGEM is also superior to the 12z, in fact it is one upgrade away from a scandi high.

I'd never have guessed from the deluge of posts 

Chilly here this evening, and that's with my beer coat on. 

Oh wow, 18Z NMM is very different from 12Z NMM, snow far more extensive and further north.

a few interesting Perturbations on the 18z suite. Steve's Danish shortwave helping to prop things up, but the majority still sink it. But a bit of hope and NAVGEM is the run of the day!

http://modeles.meteociel.fr/modeles/gens/run/gens-14-1-192.png?18

This is the best one

At 144, the high is generally looking more robust even though most members collapse it

I can't quote anyone as there are no options on my phone, the option to do so flashes up in the normal place but it disappears again and is unselectable .

Anyway, Looks like Steve (gusty) has reprogrammed the GFS op run. Much more interest this morning, even with the likely data shortages.

Well I've just been looking at the GFS 0z operational which is interesting in that we see some strong blocking to the east from mid-range.

The short term outlook looks reasonably resolved with the new low sinking south-east and deepening with a brief north-easterly.

Cold,settled and frosty up to New Year down here to follow