I think of it as Groundhog Day weather - the same thing over and over and over again, like the film of that name.

Looks as though it will continue for the next 10 days according to GEFS. 

Seems a major one occurred in September 1962, preceding the memorable freezing winter in Europe. 

I’d be interested to hear any thoughts on whether this may have a bearing on winter and how it might impact our shores, if any. 

GFS Op - HP remains the dominant force over the UK for the next two weeks, but the centre is more mobile than previously. Sat 9th near the Baltic with LP close to NW Britain; passing over UK to reach W of Ireland Wed 13th and LP near Denmark giving NE-lies for SE England; centred over Britain again 1035 by Tue 19th.

ECM - like GFS Op but from Wed 13th the LP near Denmark persists longer and affects more of England as it moves to France Sat 16th

GEM - like GFS but HP remains closer to Britain so less influence from the fringe LPs on 9th and 13th

GEFS - slow decline in temps with firm ens agreement to Tue 12th; the mean continues to cool slowly to norm by Sat 16th but the divergence in ens members becomes ever wilder and by 21st everything from 10C below to 10C above norm. Chances of rain in some runs from Sat 16th, less common but heavier in S, more common but smaller amounts in N

I'm away for the next week or so, leaving very early tomorrow, so there may not be time for a review then. Later reviews will depend on suitable wifi connections and the timetable of where I'm staying.

GFS Op - HP continues to dominate Britain, with LP nibbling at the edges (the NW this weekend, the SE next weekend. On Thu 21st LP moves from Iceland to Scandinavia and as the HP retreats W-wards, cold N-lies appear down the N Sea (last night's 18z showed this LP over E Scotland with a full-on N-ly storm for Britain)

ECM - after the 11th the LP does more than nibble at the SE; a shallow area of LP develops over S England and France through to Sat 16th (the 0z hasn't downloaded for the weekend to follow but the preceding 12z fancies N-lies for Britain)

GEM - HP maintains its dominance as for GFS Op but the N-ly plunge starts Fri 15th and is more directly aimed at Britain

GEFS - current mild temps declining to norm by Mon 11th with good ens agreement (milder again for a couple of days in Scotland 13th/14th); mean staying at norm as ens members spread out though spread is less than shown yesterday. Small amounts of rain randomly occurring in some runs from the 11th (later in SW), again varying from yesterday in its earlier arrival. 

The first chase of he year begins

Priority chase is to find a pattern to remove this nasty HP out as it outstayed it welcome.  

I’m not sure I would go as far as “cold spell” but a cool down to average or below with airflow from a northerly quarter seems favoured for a time from mid-month. This is shown again on the 12z GFS op run.

https://www.wetterzentrale.de/en/topkarten.php?map=1&model=gfs&var=1&run=12&time=384&lid=OP&h=0&mv=0&tr=12#mapref 

There has been a trend over recent runs to bring a northerly in.

Yes it's becoming a consistent signal, however I expect it will either get moderated and flattened out nearer the time, or even if it did come off as modelled then it will probably just be cold drizzle and 5c temps at best.

So, you won’t mind when people quote this when the time comes then? 😝

You could very well be correct but it’s far too early to say that it is anything other than a trend. It could be a blizzard when the time comes, or slightly cool or knowing our luck still anticyclonic conditions. Having said that, the recurrence of this pattern for the second half of the month is definitely worth noting. 

The trend is becoming a bit clearer on the ensemble data too: 

https://www.meteociel.fr/cartes_obs/gens_display.php?ext=1&lat=57.2&lon=-2.25 

This is for my locations, other locations are obviously available!

I’d be happy enough with this. Won’t be at all cold down here, but would be sunnier. This current high is amazing, but it’s a bit more murky than I’d like 

Took the words out of my mouth.

Very similar to the end of November 2010. I remember studying every frame of every run, lapping up every moment as I couldn’t believe my eyes.

By the last weekend in November this forum went into complete meltdown. Site crashes were commonplace that year!

Of course, it won’t pan out like that this time. 2010 was a one in 100 year event, probably more like one in 150 yrs by now. 

IIRC that cold period was triggered by a SSW and was well signalled ahead of the event.  I’ve been looking at the 10hPa wind forecast charts and they don’t show anything particularly unusual at the moment.

Interestingly the 850s go below average from the 11 November. Now keep me honest here, that feels like significant shift compared to even a few days ago. The 850s stay below average from the 11th for the entire run with some good clustering.

GFS Op - Current HP slipping a little E-wards with troughs for NW Britain at the weekend but HP returning from the SW early next week 1040mb and persisting though weaker to Sun 17th. Then LP from the north brings in a brief N'ly but 'pulls its punches' as it doesn't get close and winds go back to NW-ly and then W-ly by Tue 20th, before a long N-S trough develops to the W if Ireland with S-ly gales for all from Fri 22nd.

ECM - Like GFS - the LP from the north deepens significantly more over Scandinavia by Mon 18th but the wind field of the strong N-lies in this case mainly affects the N Sea and its coasts

GEM = more like GFS than ECM - something from the N by Mon 18th but not strong or penetrating

GEFS - mean temp back to norm by Tue 12th and staying a little below norm throughout. Not much agreement between ens members after the 12th, a range of +/- 5C from norm applies for most of the time and at the end the op run is wildly mild (13 C above) and the control is pessimistic (6C below). Rain appearing in many runs at random intervals after Tue 13th, perhaps a slight emphasis on this occurring in the S

Apologies for late review - struggling with network errors where I'm staying

This is, of course, a very familiar pattern in recent years. We see what looks like a northerly plunge, and one of two things happens - either the plunge passes to the east, clipping Scotland, or the plunge spins up a low to the west and bam, west-based NAO.

At least we're not in the heart of winter, so it's all academic at this time of year...

Hi Peter,

Your memory must be better than mine in this instance, as until I read your post I had no recollection of there being a SSW ahead of the freeze that started in the last few days of November 2010. I do recall that the models picked up on this at the pretty early stage and the cross-model agreement and run-to-run consistency were very high in the lead-up to the start of that freeze.

Do you or anyone else here recall if there was also a SSW in November/December 2009 before the freeze that began shortly before Christmas that year? From what I recall, the pressure set-up at the end of 2009 was almost the exact same as what was in place at the end of the following year and also as with 2010, there was excellent cross-model agreement and run-to-run consistency for a good couple of weeks before the freeze began.

Like you I have given up on snow and proper cold here. For as long as this 2 day northerly produces snow in the French Alps in time for mid december I will be happy

The reason you can't recall one is that there wasn't one. Much like the cornucopia in the Fruit of the Loom logo, in fact!

Here's a list of SSWs - others are available, but none will show an SSW in late 2010.

https://www.en.meteo.physik.uni-muenchen.de/~Thomas.Birner/ssw.html