GFS Op 0z - for this week HP stays across the north of Britain and LP in the Med generating (cloudy?) E-lies for the south. After a reshuffle on Sat 14th, a full-on W-ly zonal flow sets in for the first half of next week before oscillations appear in the flow with troughs (Thu 19th, Mon 23rd) and ridges (Sun 22nd, Wed 25th) chasing each other E-wards. Outlook for Christmas week, unsettled, but fine for Christmas itself (and that's not the same as shown yesterday)

ECM - pattern similar to GFS but timing different; the oscillations in the W-lies produce a ridge Tue 17th and a trough Fri 20th.

GEM - a less well established W-ly flow with first higher pressure on Tue 17th, then a weak ridge of HP on Atlantic blocking the W-lies and allowing a weak N/NW-ly to develop by Fri 20th

GEFS - temps up and down but mostly a little below norm, and agreement between ens members breaking up after Fri 20th; Modest amounts of rain at times in a random selection of runs from Tue 17th, perhaps a little sooner in N & W.

(Edit - I was incorrectly looking at yesterdays 12z ECM - todays looks more like a euro slug)

GFS looks too mobile and seems happy to keep the Atlantic running the show.

GEFS mean looks somewhere in the middle, with an inclination towards colder air being in the mix.

My advice is to keep a watching brief in the run up to Christmas (things can always change) and don't whatever you do take any notice of the garbage press predicting the usual snow-bomb rubbish.

Running through the postage stamps from the 06z for Xmas morning we have about 75% of the runs have high pressure as the dominant feature, of which 6 put the HP centre to our North or NE. Another 20% have LP in control. Surprisingly, perhaps, none of them have raging zonality.

More runs needed

On the other hand, ECM AIFS doesn't.

GFS Op 00z - HP currently over Scotland declining by Sat 14th as new HP cell arises over France 1035mb Mon 16th blocking yesterday's suggested zonal W-lies (maybe S England will get its turn with frost and fog?). This HP drifts SE-wards and by Fri 20th LP 990mb Baltic is projecting N-lies over Britain, not lasting as LP from N Atlantic moves in to N Sea 990mb Mon 23rd with NW-gales for Britain. This fills but only moves on slowly so fairly cold but not too unsettled for Christmas; and by  Fri  27th a large 1040mb is moving towards Britain from the Atlantic.

ECM - like GFS though LP Fri 20th covers a wider area out towards the NW with less direct N-lies and perhaps more unsettled weather for Britain.

GEM - treats next week's LP differently, localising it over the Baltic and giving all of Britain a weak ridge of HP by Sat 21st.

GEFS - cooler to Sun 15th, then milder (though location of HP may imply surface inversions in the S) to Sat 21st, then cooler for a few days with decreasing ens agreement, perhaps back to norm before Christmas. Small amounts of rain from Thu 18th onwards, not in every run. 

Don't think any cold until mid January at best

Yes, FI charts continue to show sporadic interest, but currently that is all it is.  The  MJO (GFS), now shows around half the members heading deep into phase 6 towards late December, so maybe phase 7 early January which may help?

The effect in the UK is that high pressure moves over us, topples SE'wards, and is then replaced by the next.

High pressure zonality!

Told you so those HP are winter killer, sun killer and preventing us from any proper winter seasonal with cold snowy weather.  I used to like them but now full of hatred with HP like now over us but no sun or frosty weather.  Don't know what the cause of the clouds formed under the HP while further north outside HP zone are clear and frosty.

SE USA are more south than us so if they got LP passing by then Uk will have lot of sliders with more winter actions.

That sounds like a Bartlett just displaced further north - whilst not perfect it's better than it's southern cousin!

No such fun today, ensembles continue to look very poor for cold and snow. 

😉

Even the chance of the good old SSW has waned a bit with the torques, CODs and couplings not going in the right direction. What we need to liven-up the run in to Xmas is a classic ‘where did that come from’ moment, no doubt followed by the classic ECM collapse.

I’m sure there’s a potential for a study into the mental impact of weather forecasting, in particular the effect of studying countless charts every day.

GFS Op 0z - first HP rolls in off the Atlantic 1035mb France Tue 17th, (just about stretching far enough N to reach N Scotland) followed by an LP 980mb Aberdeen Fri 20th (just about stretching far enough S to reach S England). This hangs around and deepens with re-charge from the NW 980mb Denmark Tue 24th. For Christmas Day and after the combination of HP well to the SW and LP over N Norway gives a broad swathe of long-fetch cool NW-lies; hint of an embedded weak trough moving through on Boxing Day. 

ECM - similar to GFS until Fri 20th when the LP is deeper but further away with strong N-lies for Britain; and then a more definite LP 970mb approaching NW Scotland Sun 22nd with strong W-lies instead of simply a 're-charge' from the NW.

GEM - between GFS and ECM

GEFS - temps dipping to Sun 15th, then a milder spell (but with the possibility of fog in the S nearest the HP which could knock back daytime temps locally) to Thu 19th. From then ens agreement breaks down; the mean and the majority of runs are just on the cool side to Christmas Day, the just on the mild side. Rain starts about Thu 19th, heavier and more likely in more runs than yesterday (variation - drier in the east, starting a day or two earlier in the N).

I guess it has been a different story in the south, but so far it hasn't felt like an especially mild December where I live. This week certainly hasn't been mild here and last week had temperatures around or slightly above average at best for the most part IIRC.

After all these years in a weather forum you still haven't mastered the fundamentals.

1) Summer - Boiling hot with storms or boring

2) Winter - Freezing cold with snow or boring

There is no average in a weather forum 🙂

Even here in the south it hasn't felt very mild. We haven't got above 7.5 degrees here this week which by recent standards qualifies as quite chilly I reckon. Unfortunately we haven't dipped below 4.5 degrees either, thanks to the permagloom. The last day with any sunshine at all was Dec 6th. And not much cheer in the models either. All looking very flat in the run up to Christmas.

Agreed. It’s been around 6c here all week and currently seasonably grey and misty - and flat calm.

As for the charts, I always think there’s some hope when LP systems are getting across to Scandinavia. At worst it means transient cold snaps and at best the chance for pressure to build to the south-west or west.  Although there’s clearly a recurring theme for a prevailing westerly flow, there’s still a lot of variability in the output.

The LP that forms around the Azores during Saturday is, I think, interesting, since it develops from a small cold pool that moves west under the high. It then trundles slowly north before becoming absorbed into a LP complex south of Iceland, which then drifts east across Scandinavia, before dissipating over the Baltic.