Good 12z so far ukmo and gfs both look like developing very cold northerlies by 144h.

And by 168 gfs has most of Scotland and northern England under -10c 850s.

 

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the high building from the south could well scupper the whole thing for England anyway. 

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But heights still persist across the Med. All the while they do, the true Northerly will find it very hard to develop and be sustained.

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Once again a messy picture with an Atlantic low interacting with cold air over the UK around Dec 7. A similar sort of thing has appeared on numerous runs now.

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Blizzards o'clock at 200h on the GFS. Stunning run

 

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GFS makes it in the end but I think if we could see UKMO extended, it would not be good

 

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its always stunning at 200h! 

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Well, that'd do.

 

 

 

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It really does seem to be a finely balanced picture in the medium to longer term. The potential for interesting scenarios like on the GFS 12z remains a much higher one than in previous years. It is a messy but, from a local perspective, rather pretty GFS run so far. I would be much more interested if the ECM 12z shows a similiar scenario at day 9

http://www.wetterzentrale.de/maps/GFSOPEU12_216_1.png 

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I think this pre-winter period has been the snowiest I can remember... on the charts 😉

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One day it has to be right at that range.

 

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Odd comment

 

Any chance of the lottery numbers

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Not sure why you say that, Beast.

Yes, UKMO shows the HP just to our west at the weekend moving southwards towards the Med, but at the same time pressure looks to be building over Greenland. That of course wouldn't guarantee more cold weather as last week showed, but I don't think that just because the weekend High is shown to move south, it should be automatically taken as a one-way ticket back to zonality.

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Thundersnow event? Or heavy rain turning into heavy wet snow - huge flakes but melting!?

 

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Yep, it's all over by T+288.

So from about 150 or 160hrs to 288hrs, not bad if it comes to fruition.

(Incidentally it is nice to view the latest potentially wintry runs at day 6-7 when the increasingly snowy showers are passing through )

A glance at the emerging GFS ensemble data suggests a trend toward colder in the medium term but we will see properly in a while.

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GEFS shows for Friday 7th a 70:30 split cold(NW or N): mild(W or SW)

At Sunday 10th the spit is 50:50.

Latest run going for a potentially deep cold spell setting up over the eastern half of the States from next weekend.

Could help fire up the N. Atlantic Jet down the line, but which 'arm' of it is the question. 

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Indeed.

If I had to make an educated guess, I'd say the chances are quite high for this pattern to persist throughout most of December. The weather is far from zonal and to me, it seems like this pattern is emerging as the front runner in the ENS too.

Incidentally, odds are being slashed on a white Christmas and even for the winter as a whole for one of the coldest.

I would say that the background signals must be there for a noteworthy freeze through December.

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Only 3 runs on the GEFS for my location are over -5c on the 850s on that date. Definite shift in emphasis to the colder cluster.

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if it happens will put a lot of people's theory to the test

Only parochially and temporarily- by that time, more sensible cold gives us another power piece on the synoptic chessboard: the Scandinavian cold is settling in for the winter.

https://www.theweatheroutlook.com/charts/gfs/12_288_mslp850.png?cb=186

 

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It's an interesting chart in that the cold air is exiting the continent at a more southerly point than usual, and this over exceedingly warm waters. Only time will tell what this might lead to, if it leads to anything at all. 

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Some real volatility on tonight's GFS run for down here (especially in the 7-10 day range). Two sub 520 dam episodes interspersed by two milder and much wetter interludes within the next 10 days. Indicative a very close running jet. The colder shots are associated with NW'ly's meaning that for down here any snow will be very limited or non existent. 

Fascinating model watching 

http://wxweb.meteostar.com/sample/sample.shtml?text=EGMD

 

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 Spooky, I was about to post the same link for Aberdeen (EGP) as it shows 500-1000hPa values dropping to 512dam by 162hours. Methinks the GFS model is overdoing the cold (up here at least) but time will tell.

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