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Its freezing out there and looks to get even colder over next few days.

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html 8-10 day 500mb charts continue with the theme of low heights to the south with one lobe of the trough over the eastern Med and another close to the Azores. The ridge to the north is flatter, slightly further south being squeezed between low height to the north and the low heights to the south. 06Z GFS shows the surface high meandering in the vicinity of the UK and western Europe which could give frosty nights with potential for freezing fog and inversion cold. At the same time western Europe is expected to slide into the freezer especially if it manages to catch more of a snow cover over the next few days and a drift from the continent could be decidely cold. 2.5 CM of snow here this morning and still on the hills so feeling optimistic.

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html Latest 8-10 day 500mb charts both ECM and GFS show a sustantial block in the east Atlantic which has gradually evolved over the last few days. The slow but steady evolution and with little change from yesterday could be a sign of some stability to this pattern. The Azores high is displaced to the north being propped up by the upper trough that is shown to extend ever further westwards from the Med to the Azores. The cold spell originally predicted to end tomorrow looks likely to continue for a while yet at least in the south.

Yes thanks don't know what happened there...you are absolutely right.

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http://www.meteociel.fr/modeles/gfse_cartes.php?ech=6&code=0&mode=2 Quite an upgrade on 24 hours ago with the cold pool extending further west over UK in the medium term and a large area of snow develops over central Europe and edges NW towards the UK. This presumably on an occlusion as warmer air over the eastern Med and SE Europe pushes north and meets the polar continental airmass,

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html 8- 10 day 500mb contour charts show a tendency for blocking across parts of the N hemisphere. The low heights shown to be extending westwards to the south of the UK result in the Azores high being displaced slightly further to the north with ridging to the NE. The southern half of the UK looks to be at increasing risk of cold as it comes more under the influence of the developing vortex to the south.

http://www.wetterzentrale.de/pics/bracka.gif The Met O have analysed a low to NW of Scotland at 12Z and the plotted chart shows an opening of the isobars over NW Scotland. http://meteocentre.com/analyse/map.php?date=0〈=en&map=UK&size=large

I have not seen any upper air ascents but I would imagine there is a steep lapse rate in the unstable polar air over the UK at the moment which will be conducive for precipitation to turn wintry once it starts.

What a rubbish winter so far. It was much better last year with hail falling from the sky every other day and sometimes every day for weeks and sometimes it would accumulate. This year all we can manage, at least down here, is the old light rain shower and temperature around 7C. During a northerly In a proper winter the 510 DM line would be at least approaching Scotland and occasionally would extend into the SE yet at the moment it is lost somewhere near the pole. Complete rubbish however I live in hope and the next week or so does look a bit more interesting. This is more like it !.http://www.meteociel.fr/modeles/gfse_cartes.php?mode=3&ech=6

Met O TV forecaster seemed highly confident at around 5.00 pm of bitter north winds setting in later Wednesday and kept emphasising how cold it will be.

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html 8-10 day 500mb anomaly charts show a deep trough over mid USA and another over western Europe giving a particularly long wavelength. If the wavelength is sufficiently long the waves can become stationary or even start to move backwards i.e. retrogression..

http://meteocentre.com/analyse/map.php?map=Europe&date=2015012211&size=large〈=en&area=eur A rare easterly has arrived across more southern parts. Not spectacular but relatively cold compared to the winter so far. Patchy light snow is evident upwind over the near continent at 1100hrs.

http://meteocentre.com/analyse/map.php?map=Europe&date=2015012110&size=large〈=en&area=eur As the low slips to the south of the UK the flow backs drawing in drier air from the near continent where modest cold pooling is occurring within the cold high. The south easterly fetch from the English channel is keeping temperatures relatively high along the south coast at the moment but as the wind continues to back even here temperatures look set to fall away. So a couple more quite cold days and nights ahead for much of the UK.

http://www.wetterzentrale.de/pics/brack2a.gif Note the position of the 510 dm thickness line which is shown extending southwestwards from Russia towards Italy at T+84. This is several hundred miles further SW than on the previous run.

http://www.meteociel.fr/modeles/gfse_cartes.php?ech=6&code=0&mode=2&runpara=1 The upper ridge becomes cut off to the NE on the 18Z GFS P but extends ENE towards the southern Baltic on GFS. A mugs game I know but I'm going to back the GFS P tonight at around T+180 for the next chance of some snow. Even GFS suggests a cold frosty period for a large part of the UK with a drift originating from what looks likely to be a frigid continent.

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html Latest 8-10 day 500mb anomaly charts are very similar to yesterdays although the upper high on ECMWF is positioned slightly further NE and the GFS upper low over the central and eastern Med is more of a feature today. So some consistency over two days with a slight improvement if you like a cold outcome.

http://www.wetterzentrale.de/pics/brack2.gif Wave depression on T+72 FAX slightly further south than previous run as are the high cells to the south of the UK. This wave is expected to deepen rapidly as it tracks east across N England before it turns southeast.

Almost perfect omega shape to the block at T + 192.

These later charts make better viewing.. even the GFS shows some noteworthy buckling near the UK and E Pacific. http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

The time seems to be updated sometimes long before the text. Reckon it needs sorting.

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html ECMWF 8-10 day 500mb anomaly chart is today indicating an omega block over the UK with low heights over the Med. There is a weaker block also with a vaguely omega shape in the eastern Pacific. The blocks are less well marked on GFS but nonetheless are indicative, if they verify, of a slowing down of the northern hemisphere circulation perhaps allowing a colder period to evolve over northern Europe.

There was a chap I used to know that made a forecast for the week ahead solely from the 100mb actual charts. I cannot remember if his forecasts were accurate but he was well respected so they may well have given a good steer. The scandihigh2 chart might well give potential for cold from the east if it were to verify.

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html The 8-10 day 500mb anomaly charts show a strong northerly component across the UK with ridging to the W of the UK . The northern part of the ridging over Greenland is further east than yesterdays output as is the trough to the east. The last few days have seen variable patterns projected at this timescale at 500mb with the strong ridge extending west-east to the south of the UK now transferred westwards into the atlantic. It remain to be seen whether the latest forecast pattern will be replicated over the next few days but there has been a trend to a more favourable pattern for cold over recent days. Models are toying with the idea of cold outbreaks every few days. Even xmas day although not snowy looks pretty cold. With the close proximity of such cold air to our north and the presence of the Greenland Ice cap with some evidence of ice flows extending eastwards from the Greenland coast north of Iceland there must be a possiblity that any northerly outbreak although short lived could be potent bringing the prospect of snowfall to many parts.

http://www.meteociel.fr/modeles/gfse_cartes.php?ech=6&code=0&mode=2 18Z GFS T+84 also shows a hint of snow along part of the S coast of UK and this time within a patch of -6 C 850 temps .The channel low is slightly further south but does seem to keep popping up in the GFS output.