Purga

Of course the only outcome has to be P16

De Bilt ENS showing a good very cold clustering trend = Easterly MO Positive for Holland and us as well we hope. EDIT: PS Note the Op is on the MILD side of the run!

Majority of ENS trending cold with the Op & Control at the cold side of the pack. Always an interesting sign when the Op & Control concur.

Some snow to cheer Mr Murr up.

OK - then what would you do if the ECM Control run came off Karlos?

ECM 12z is great in the latter stages Nick but to paraphrase John Cleese's quote “It's not the despair, I can take the despair. It's the hope I can't stand" ! ECM 12z 240hrs GFS 12z 240hrs Compare and bear in mind ECM verification stats are at 70% for day 10 whilst GFS is at 50%.- no guarantees of course but the odds a bit in our (cold) favour.

An easterly - a slack one and not a very cold one but still beggars can't be choosers......

Some decent cold clusters showing in the EC ENS

Very nice ECM 240h chart Not particularly cold uppers but the synoptics are packed with potential

GFS 18z shaping up very nicely in FI

I guess I keep beating the same drum... but ENS showing consistency again GEFS06z It's worth a gander at the T2M as well (for London) as it's showing temps averaging not much above the 0C line as we move on. Only a few members briefly breach the 10C line The Control run was none too shabby in the later stages I know it's easy to be cynical and understandable in this good Island of ours but as the saying goes there's still 'all to play for'. PS: METO further update today still retains the chance of a v cold blast from the East later in the month albeit a very small chance.

Looking ahead - the ECM 46-day control run is very nice if you like cold - it shows persistent E'ly winds after D14. Trough disruption to the west at D10, with LP moving SE under the AH which increases heights and drifts E near Iceland. The combined high settles over Scandinavia.giving a very tasty pressure profile towards the end of the month. The ECM control on todays EC15 shows a broadly similar picture. The latest EPS & GEFS06z both show continuing consistentcy and signal colder conditions after mid month Admittedly until we get to mid month the 'reliable' time frame charts are not that scintillating but I'm still optimistic based on what the ENS suites are showing & have been showing for a while now.

Thanks Knocks - give us a nod when they're out....

Do you know what EC46 has shown?

Maybe a bit too much over analysis & understandable frustration at the moment in a slowly evolving move towards colder conditions. The ENS 06z so far, are showing continuing consistency in a post mid month cold spell of some sort. Checking the postage stamps will show that circa 50% of members develop a cold NEly flow very close to or over the UK - courtesy of a 'trigger low' moving SE. Te ECM control run develops a cold SE flow with potential for interaction with similar LPs shifted more to the west. Of course this may change but based on successive recent runs this is a positive sign for cold aficionados. The degree, longevity and character of such a spell is open but the signal still appears to be there - not to mention the BBC latest outlook ! http://www.bbc.co.uk/weather/2635167#outlook Keep smiling!

In fact the many available charts you refer to use the same basic data as the operationals - it's just different ways of representing aspects of that same data so one may as well just look at the big 3 NWP models and be done with it! I guess it just helps oil the forum discussions to see representations of same thing from different viewpoints.

You're not visiting Belfast on that day are you Steve?

We are just entering ostensibly -ve NAO & AO phases which are built into the model outputs. A casual glance at the ensembles recently shows that beyond about 7 days there is so much divergence that the situation is effectively unforecastable to any useful level of reliability beyond 5 days and the only guide for forecasting further ahead is to analyse clusters and try to spot consistency over several runs. I believe that looking at 'mean' charts can be pretty useless - The mean is only useful if there's only one cluster! EPS & GEFS 06z After D10 there remain significant cold clusters and this is being reflected in the GFS operation runs recently. Of course it's frustrating for all us cold & snow lovers that things always seem to be always 'out of reach' but there is a continuing signal for blocking and the potential for cold coming from the NWP. It may not give us exactly what we 'want' but the potential is there and much better than it has ben for some years.

It's easy to be obsessed with the operational runs but one has to see the whole package - which will let us see that nothing has really changed over the past several runs, both GEFS and EPS. Tonight's 12z GEFS actually has a majority of runs bringing NE'lies or easterlies at some stage in FI. The longer such NE'lies or easterlies persist the better are the chances of something 'tasty' happening, Note that here are plenty of -10s on offer in the suite. The shift in the UKMO & ECM DET runs tonight illustrate the uncertainty at the moment per the GEFS spreads. If either the 18z or 0z tomorrow will have one of the -10 runs as the op then all the angst and doom laden posts will be replaced by a more objective discussion. ECM EPS awaited wth interest folks.. Happy & Healthy New Year to all & hope for load'sa snow!

With respect to some recent posts one could think that all hope of cold weather had gone, Note that we still have 8 runs breaching the -10C 850 mark in London - the same as the 12z GEFS of yesterday. It never happens that the number of -10C runs increases with each model run... not even in 2010 did that happen. The ECM ensembles remain solid in showing a majority cold cluster. The MetO updates are largely based on the ECM output and it's no surprise to see no alterations there. The next major update is likely to come on Tuesday when the next run of the ECM monthly model is made available. Look - 40% of the ensemble members show very cold weather still, what would we have given for that only a few weeks ago in early December yet alone in the last 2 years! Anyway, with due deference to our mods wishes, a brief mention that Darren Brett on BBC news channel hinted at very cold conditions from next Friday with NE winds per last night's update. Of course it can always go the way of the pear but I'm not ready to throw in the towel yet - and please feel free to say 'we told you so' if it does!

Colder trending ECM ENC for DeBilt A lot of scatter in the GFS ENS but stronger cold clusters and the mean staying on the cold side pretty much throughout. http://www.wetterzentrale.de/de/show_diagrams.aspx?model=gfs&var=2&lat=51.5085&lon=-0.1257&lid=ENS&country=de&zip=&bw=True Note that even the members that peak 'mild' do so fairly briefly and also show cold or very cold troughs. Much to be resolved still but mild and zonal it ain't!

Don't forget P14 Steve, as Frank Carson used to say 'It's a cracker'! (showing my age...)

The short GEFS still looking good even at this stage with some very tasty perts evident Of course, just for balance we have the odd spoiler http://www.wetterzentrale.de/de/show_diagrams.aspx?model=gfs&var=2&lat=51.5085&lon=-0.1257&lid=ENS&country=de&zip=&bw=true But most of the clustering is on the cold side and the mean stays resolutely cold after D8

The UKMO was a variation on a theme and only goes out to 144hrs which is probably far enough in the current situation ! It's never wise to over react to one or two model runs but try to look at the bigger picture and the ENS for the three main models GFS, ECM & UKMO. After this weekend we get a second northerly blast and then we get deep cold into mainland Europe and high pressure building strongly to our north-east and then north, advecting cold air west. Keep the faith...

Interesting where this run is going to! Quite a bit different isn't it,,,,