It ran on time as did the GFSP.

http://www.theweatheroutlook.com/twodata/datmdlout.aspx

There is both cool and mild spells and equally to that also spells of cold Zonal Outlook, if GFS and UKMO are to be believed, and this is true to last at least to about 27th December, North Atlantic PV Low Pressure Jetsteam SW, Cyclonic and NW flow at times, with some occasional two day or one day High Pressure ridges temporarily giving bright and less cold weather and as we get NW flows it should bring quite a few overnight frosts, even early and late in day ones.

Arctic Norwegian Sea and around Greenland, Low Pressure that crosses the UK and affects Canada plus NE USA and Northwest to North Europe as well, some wintry showers and hill snow expected as well as heavy rain spells/ showers hmm.

Going much better than last December we are getting the full variety and that is reasonably acceptable to me.

Roll on winter...

The Azores high looks likely to avoid affecting our weather too much but a crisp sunny few cool days with it's ridges at some occasions is pretty fairly accepted on my books.

😄.

Yep - wrong thread but worth putting here just to lift the spirits of us desperate model watcher colides:

UK Outlook for Thursday 25 Dec 2014 to Thursday 8 Jan 2015:

there is a signal that conditions may become colder particularly into the New Year, although the is a large amount of uncertainty surrounding this. Temperatures are expected be around average for the time of year, the may turn colder than normal in the New Year.

Updated at: 1442 on Wed 10 Dec 2014

http://www.metoffice.gov.uk/public/weather/forecast

just to add to this. 

Ian Ferguson Netweather

A few of you have asked today about rationale for the (tail-end of) UKMO latest 30-day outlook. There is, of course, a dedicated thread elsewhere for this but I'll just confirm that GloSea5 output remains the rationale behind the wording of the outlook towards end Dec-New Year, with some interesting/intriguing signals into that period. That's all I can share at present.

agreed, it's only 10th of December so plenty of time for change, though I think the next 7 days or so are generally nailed in sense of zonality. That takes us to the 17th, so I would expect the output to start showing the MetO thoughts at perhaps about this time ?

Still nothing really cold out to Christmas apart from a sharp dip this weekend.

Ah those mystery 'signals' about which no one is allowed to speak. There's nothing like a good conspiracy is there?

On a positive note, we have had more frosts thus far this month, than we had in the whole of the last sorry excuse for what some people may refer to as winter, but which doesn't deserve to be called such - the extended autumn from Hell, 2013 - 14.

Hi Brian, I do like using the mouseover effect on this (on a pc) but the numbers appear in quite an unexpected order so there is a bit of hunting around to see where the next one is. It does the same for me on 2 different pc's, is it a universal issue or just specially for me? Just thought I'd mention in case you weren't aware.

Cheers.

I'm sure he doesn't post as some sort of feeling of duty, so he clearly enjoys whatever he gets out of it for himself. 

Some people just criticise everything and anything. 

So there is a chance, maybe 50/50, that the fist signs of the colder weather may start to show up in the models in the period from 18/19 December in the farthest reaches of FI.  If there is little or no eye candy available by around Christmas day then it will be safe to assume that the models referred to by Ian F have changed their minds, by which time the Met O LRF will have changed anyway, and we will be looking further ahead for some salvation from a moribund winter.

WI

Whats the mystery?

The long range models the meto use show a signal for colder weather at the end of the month. 

I take little notice of any forecast over 7 days. As no one or any model has a clue what the weather will be like in 20 days for the UK.

The Scandi trough is looking considerably more potent on todays output, with the idea of the Siberian High edging west, explored by a good number of ensemble members recently, well and truly put down by the operational runs at least.

The ECM run almost blows it away completely, as it has the most intense Scandi trough with the least distortion taking place (i.e. the lows bear the most resemblance to a dartboard). GFS, GFSP and JMA are less vicious but it does appear that the jet will be too strong to permit any easterly option from evolving.

With that in mind, thoughts once again turn to any means of enhancing the northerly incursions on the rear flank of those storm systems.

The developments of most interest to me in the 12z op runs are:

That low in the far-western North Atlantic has been adjusting south with each new run (though only slightly in the case of ECM), with a little more of a ridge ahead of it. This suggests a toning down of the southern arm of the jet, which I reckon gives a small chance that the low becomes a cut-off feature with a marked Atlantic ridge to the NE of it, rather than riding the main Atlantic jet to the UK as happens in all of the 12z operational runs.

It requires every operational run to have the jet modelled incorrectly, so I'm not counting on it, but after what happened with this weeks low, it's not hard to imagine.

While that first low doesn't become cut-off, things work out very differently for the next low in that region on the ECM, JMA and GFSP runs:

This low, which tracks through the southern states of the U.S. days 3-7, becomes cut-off in the western North Atlantic as the southern arm of the jet does not fire straight NE to phase with or run parallel to the northern arm (for those wondering what I'm on about, these 'arms' represent branches of the jet stream that are associated with the two areas of most rapid horizontal temperature change in the North Atlantic).

This idea of a cut-off low was present on yesterday's 00z runs before being dropped for a couple of sets of operational runs. It has the effect of encouraging the Azores High to ridge north in the middle of the North Atlantic, enhancing the day 10 rear-flank (of the Scandi trough) northerly on both the ECM and GFSP runs.

Ideally, this would be followed up by any later troughs across Canada or the U.S. digging south to merge with it rather than 'scooping' it out as the GFSP 12z op run does. ECM could be having a go at the end of it's run but it's not a very convincing attempt.

So there lies one of the most significant aspects of the model output to keep an eye on - there does look to be an increasingly prominent jet stream across the southern states over the coming 10 days or so, and the way in which the associated lows behave as they reach the Atlantic will greatly affect how flat or otherwise the Atlantic pattern becomes, how far into Europe low heights manage to get and so on. That in turn may change the fortunes of the Siberian High.

The models also seem to be really struggling with how the MJO behaves in the coming week or so.

In fact this does seem like the sort of situation in which the true solution remains in hiding until a sudden emergence without much warning.

It really is no wonder that Fergie's comments have been laden with caveats regarding high uncertainty!

If those long range models are showing a 'signal' it must be capable of being expressed in words e.g. "significant number of ensemble members showing positive height anomalies over Scandinavia" or some such. The mystery is the conspiracy of silence over what the signals are.

I guess the people that can view them, can not comment in much detail on what they show 

As if you wanted detailed information of what they do show, you probably have to pay a considerable amount of money for it.

They may just show things 'slushing' around a lot more with less progression appearing. In this case the chance of a pattern change bringing a cold outbreak is increased, but the way the blocks fall may remain very uncertain with no clear frontrunner. I think his comments make perfect sense (the MetO 32 dayer too) and putting more detail in may be pointless. Conspiracy of silence? No. More likely not strong enough guidance to make a deterministic judgement.

Hit the nail on the head there.

It's the biggest thing separating analysis by the public on this side of the Atlantic from analysis on the other side where free data is king.

Should be left to right - right to left - left to right etc

Like this:

Yes I'm sure this is it. Even uncertainty can be expressed adequately in words, as in Brian's example above.

Just for fun, here's what the day 16 chart of the most extreme operational run of November had us down for today:

A great example of why we call the output beyond the reliable range 'Fantasy Island' 

Well possibly, but I'm not convinced. The ECM data costs in the region of £100k per annum for full access I seem to recall from speaking to them. The value is debatable. Frankly most consumers want to know what the weather will be, not the synoptics which bring it about. At day 16 - 32 the ENS value is in identifying trends and signals, not the details. The Met Office disseminate this information via the 32 dayer and contingency planners forecast. Personally I would like to see the American model of data access adopted in Europe for obvious reasons, but these certainly don't include knowing whether the emphasis on the latest ENS between days 16 and 32 is blocking over Scandi or Greenland. 

Fantasy island Indeed James, but a cracker of a chart none the less, lets bank it for January instead

Closer to a cut-off low on the 18z GFS op with more of a ridge ahead of it so FI might be more fun to look at... getting close at day 9.

Anyway, I'm off to watch Live at the Apollo, here's to more interesting output tomorrow... please