The UKMO is still good, and better than GFSand ECM have been showing until late, but heights have dropped to the north and west to what was showing previously, reducing robustness of cold spell accordingly.  as such I think 'downgrade' is a reasonable term to apply to it.

The first attempted mild push on Monday fails. By Wednesday lots of the UK are in the freezer at 1pm.

The same is true, if not more so down here, but it does feel bloody freezing out at the moment, but I put that down to it being so long since we had ANY cold weather. 

I'm looking forward to some decent frosts from the weekend,  and we'll see what next week brings. :-) 

Indeed GFS has been thoroughly beaten up by the ukmo over the last week very poor. Hopefully people will stop posting pointless NH stats that suggest GFS is equal to the ukmo. For our part of the world it's very much a distant 3rd.

Daily ninja post...

Off topic, but I forgive myself as I'm quoting you. What do the stats look like in summer heatwaves? I follow the models far more obsessively in the summer than the winter but I suspect I'm in a minority.

Running Brian's 'UK Precip Type' chart viewer this morning for the 0z GFS run illustrates really well several attempts of the Atlantic to displace the cold only for the fronts to fizzle and slide SE. Current timings show the first on Saturday daytime, and a second on Monday with the battleground/snowline currently shown from north Wales in a line to Portsmouth. Again, this has trended slightly southwest based upon yesterday's runs...and this is the GFS Will be interesting to see how that changes today.

This is when the forum and site massively diverge. TWO's busiest months of the year are generally May, June, July and possibly August. This is because people are doing barbecues, holidays, festivals etc. and the weather has a massive impact. During the winter months the weather passes many people by unless there is substantial snow or exceptionally wet and windy weather. However, the TWO forum is generally less busy in the summer months, presumably because most people who can be bothered to register are 'hardcore' snow fanatics! 

or (tongue in cheek) could it be that in the winter it's a higher percentage of snow starved southern/ lower England folk craving snow? Where as in the summer those same folk see generally fine warm weather at least a couple times a week 😄😋☀️⚡️❄️☔️🌅

HERE IS MY LATEST ANALYSIS USING DATA SUPPLIED BY THE NWP OUTPUT COVERING 5 OF THE WORLDS MOST POWERFUL WEATHER COMPUTERS ISSUED AT 09:00 ON WEDNESDAY JAN 13TH 2016

THE CURRENT GENERAL SITUATION A weak ridge of High pressure will move away east today followed by an Atlantic depression and fronts moving erratically ESE across the UK tonight and tomorrow

http://www.wetterzentrale.de/pics/Rtavn001.gif

CURRENT SNOW FORECAST AND FREEZING LEVEL OVER THE UK The freezing level across the British Isles will lie around 1000m or 4000ft today and falling further towards 500m or 2000ft in Northern and Central parts later tonight and tomorrow.

http://www.snow-forecast.com/maps/dynamic/uk

http://www.natice.noaa.gov/pub/ims/ims_gif/DATA/cursnow.gif

MODELS-2 WEEK HEADLINE Cold and frosty with the chance of snow in the South for time early next week then becoming milder.

THE GFS JET STREAM FORECAST The main theme of the Jet Stream today shows the Jet Stream continuing streaming East across France at the moment before it changes to flow South across the UK by the weekend and start to next week. It then breaks up for a time before realigning on a much more Northerly latitude in the second week.

http://www.netweather.tv/index.cgi?action=jetstream

GFS OPERATIONAL The GFS Operational Run today shows cold conditions lasting across the UK for the next week as the cold North or NW flow with wintry showers is replaced by High pressure crossing east over the UK with fine and frosty conditions likely. Then for a time next week a battleground between milder Atlantic air and cold air across the UK is played out across the SW with rain and snow likely for a time before a more general switch to milder Atlantic SW winds take hold from the middle of next week with some rain at times in the NW. It could become quite mild for a time especially over the South and East before things cool down again by the end of the period with the return of frost and fog patches nigh and morning as High pressure re-establishes near the UK.

GFS CONTROL RUN The theme of the Control Run shows a very similar pattern to the Operational with a messy transition away from the cold pattern towards the middle of next week to much milder SW winds with rain at times thereafter though changes to somewhat colder conditions on a NW breeze looks likely at times too with High pressure never far away to the South and SW later keeping things largely dry and benign there.

http://www.wetterzentrale.de/pics/Rtavn1441.gif

http://www.wetterzentrale.de/pics/Rtavn3841.gif

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=144&mode=0&carte=0

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=384&mode=0&carte=0

UKMO The UKMO model today is again wanting to prevent milder Atlantic air into the UK next week with a push of mild air into cold air across the South of the UK likely early next week with potential for significant snow in the South and SW early in the week and cold and frosty conditions maintained elsewhere as Low pressure to the SW disrupts and slides ESE into France.

http://www.wetterzentrale.de/pics/Rukm1441.gif

THE FAX CHARTS The Fax Charts show a cold North to NW flow with wintry showers near coasts giving way to fine and cold conditions as frosty High pressure moves slowly East across the UK at the weekend.

http://www.weathercharts.org/ukmomslp.htm#t120

GEM GEM this morning shows cold and anticyclonic conditions from the weekend as High pressure is maintained close to the UK for the early days of next week. On this run there is no push of Atlantic air into the SW so no snow risk shown before milder air moves across the UK from a more NW'ly direction in a much less eventful fashion with the run ending in relatively Atlantic based winds for all of the UK in 10 days time.

http://www.wetterzentrale.de/pics/Rgem2401.gif

NAVGEM NAVGEM looks fine and settled this morning but cold. Once the next few days of wintry showers have cleared away East over the weekend the beginning of next week looks generally cold and fine with frosty nights with the run ending with a large High pressure area close to or over Western Britain in he middle of next week.

http://www.wetterzentrale.de/pics/Rnvg1681.gif

ECM ECM today has changed markedly since yesterday morning and now has followed the lad from UKMO in maintaining cold across the UK until the latter stages of next week at least. High pressure moving into the UK at the weekend will replace the wintry showers near eastern coasts giving most places a very frosty, bright and cold weekend. then early next week low pressure fronts to the SW move into the cold air before shearing away to the SE. Snow is likely from these across the South before fine and cold weather returns midweek. Then towards the end of the run High pressure is shown to collapse SE allowing mild SW winds to make inroads across the UK from the NW.

http://www.wetterzentrale.de/pics/Recm2401.gif

ECM 10 DAY MEAN The 10 day mean chart shows High pressure likely to lie to the South or SE of Southern Britain in 10 days time with milder conditions having spread to all areas by that time. Pressure is unlikely to be very low so the South and East could be largely dry and benign but stronger SW winds across the North and West will more than likely lead to some rain at times here.

http://www.wetterzentrale.de/pics/Reem2401.gif

NOTABLE TRENDS & CHANGES FROM PREVIOUS RUNS The models continue to show different options towards how the extension of the cold weather across the UK takes place. However, the end theme remains for milder weather for all by the end of next week. 31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The verification Statistics of GFS, UKMO and ECM show at 24 hours ECM ahead at 99.6 pts with UKMO and GFS at 99.4 pts respectively. At 3 days ECM is leading with 97.5 pts to UKMO's 96.6 pts while GFS lags behind at 96.1 pts. At 5 days ECM leads with 89.4 pts to UKMO at 87.6 pts then GFS at 86.9 pts. Then at 8 Days ECM still leads at 66.1 pts over GFS's 63.1 pts. Finally at Day 10 ECM is ahead of GFS at 49.2 pts to 46.8 pts respectively.

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day1_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day3_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day5_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day8_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day10_PMSL_MSL_G2NHX.png

MY THOUGHTS In the last few days there has been a marked stand-off between most of the output and what UKMO has shown in the evolutions of milder air reaching the UK next week. In the last 24 hours this seems to have been resolved with most of the output returning output today more akin to that of UKMO so hats off to that model for sticking to it's guns. The result of this is that I can now more confidently say that the UK is going to stay cold rather longer than previously thought and it looks like the end of next week at least before many areas see a return to Atlantic winds. More importantly for many is that there looks to be a real risk that a period of snow may affect the South and SW early next week as mild Atlantic air pushes against the cold air established across the UK before shearing it away SE into France. As is usual with these situations details of where, if any and how much snow will fall will not be realised until later in the weekend and for many it is likely to just stay cold and frosty with sparkling sunny days. Then as we look longer term all output that stretches out beyond the middle of next week still show the Atlantic winning back with all areas becoming milder with some rain at times particularly in the North. However, as has been proven in the last few days that is a million miles away in weather terms and there is plenty of time to suspend any milder air into the UK even further. It is a welcome relief I'm sure for those afflicted by recent floods to see a week or so at least of much drier and cold conditions to alleviate and expedite a slow return to normal life and if you live in the South going on this morning's output there is a real risk of seeing some snow early next week. For many this will be the first time a snow event from the SW such as shown has appeared in the charts in a reasonably short time frame for some years. It will be fascinating to see how this unfolds within the models over the coming days and the longer term prospects too. See you tomorrow for the next instalment.

Next Update Thursday January 14th 2016 from 09:00

Great summary Martin, sums it up perfectly. 

Great ECM today and a snowy UKMO, can someone post the GFS 00z ens please?

Morning All 

Fantastic Model watching over the last week or so, I really don't think we will see the return of the weather experienced in December anytime soon, The potential at the weekend into next week for some snow and it does look like there is the possibility of some very low overnight minima, and close to freezing daytime temperatures.

BRRRRRRR

We are going to be very fortunate to ever see conditions like December 2010 again which I'm sure we will, but they will not happen every year so we need to take what we can get.

DB

... And daily sight of the ECM median high not reaching 4C again until day 10.

I seem to have been posting exactly the same comment every morning for the past week.

If only we could see this diagram at the same time as the operational charts are published, it would save a lot of Angst. 

agreed, infact - its been a long while since ive studied the isobars i sunch detail.  Its so finely balanced that the slightest incorrectly aligned isobar could spell doom for alot of people.

Good to see ECM and MET go for something perhaps emerging from the north in the coming days - im hoping we stave off the atlantic till then.

The stand-off between UKMO and ECM/GFS over the past few days has a lot of similarities to what happened for a number of days back in early-mid Feb 2007, only this time the roles have been reversed. Whereas in recent days the UKMO has gone for a colder solution and GFS/ECM a milder one, in 2007 it was UKMO that remained milder while the other two at different times both contemplated a major easterly spell. UKMO had the upper hand that time though, and it would appear that the same may well prove to be the case this time.

Does show though how unwise it is for one to make assumptions about what the models will likely do next though, doesn't it!

Referencing Steve's post yesterday about the theta e charts, look at the start of next week now:

http://modeles.meteociel.fr/modeles/gfs/runs/2016011300/gfs-6-144.png?0

I'd love to be in the Lakes this weekend Andy...I'm walking tomorrow and Friday in the Southern Uplands which are already snow covered. As you say the models suggest cold bright and frosty!

Don't think tonight's snow will reach quite as far north as Edinburgh sadly but the Lakes will do well

Indeed Brian. While there remains some uncertainty about close-range prospects, it is virtually impossible for anyone to be anywhere approaching sure about what follows in the medium and longer range.

A couple of days ago many people seemed to be almst 100% convinced that UKMO would eventually fall into line with the quick return to milder conditions that GFS and ECM have been suggesting over recent days. So far it hasn't happened, and looking at the UKMO 00z run this morning I would say that it doesn't look any more likely to happen now that the UKMO runs over the past few days have indicated.

Looks like the UKMO could be onto something . 

Fascinating output and it has been enjoyable following this thread in the process. The ECM 00z is a fantastic run which maintains higher SLP to the NW. Throughout most of this run we are under slack northerlies with 850hpa temps below -5, which will produce increasingly cold surface temperatures at this time of the year when the sun is still weak.

The longevity of the cold spell hinges on how far north the anticyclone next to the UK on Saturday builds north, it really is a borderline situation. However given we are getting pretty close now and the models are falling more in line with the UKMO. I can see this cold spell being extended a little yet again at least.

As Brian says, the further the Atlantic is pushed back then the more scope there is for mid term changes,  however the AO is expected to turn more positive and that, as the models show, will mean low heights at Northern latitudes.

Sorry it's late!

But as you know the AO and NAO forecasts are model based like everything else, so also subject to the vagaries that have afflicted the NWP of late.
AO can fall as well as rise just as unpredictably.