Could be an exceptionally snowy period for much of the UK, in terms of frequency of snowfall (and, indeed, depth for some lucky places)

However, I'm remaining sceptical as there is little in the way of cross-model support for a snowy spell (colder, yes, but not all showing snow) and the MetO aren't going big on snow for most areas - least of all here.

GEFS6z again shows a pretty consistent picture with a colder period. The snow signal doesn't look particularly strong in the south east at least. 

PS: Had confirmation that the 12z op will be the GFSP and the GFS is no more.

Interestingly - down here (Sussex) has rain from each of these.  I guess it's always a little too marginal - but seems a bit unfair.

To be fair Kieran, as you are a fellow seasoned campaigner, you should know the score:

First get the cold in (nailed), then:

 - monitor fax charts

 - Met updates

 - Ian F tweets/posts

Those weatheronline precip charts are a waste of space and not worth posting and the faxes are your best bet to find troughs etc.

As a seasoned campaigner we never had the twitter option back in the day.  But yes, I agree.   Just my pessimism kicking in. 

The way it's shaping up next week for the far south, it has the potential to bring good falls of snow... or a lot of frustration as conditions tend toward the wrong side of marginal.

Recent GFS and GFSP runs have been very much hit and miss with the snowfall down here, particularly for the weekend as it looks to come down to weak disturbances with showery activity the main source of precipitation. Can we get enough convection without the disturbance developing to the point that it draws in air from the ocean/seas? GFS/GFSP are rather lacking in precipitation but we know how things can crop up at short notice.

With the flow looking slack, it may come down to where heavier bursts of precipitation occur to get snow to low levels.
A similar situation to last night really - for example, around 7:30 this morning, a heavy snow shower passed just north of here, and heading up the road I saw some cars and even the odd roof sporting a cm or two of snow. By contrast there wasn't a single flake here as far as I could tell (it was rather dark when the only shower of the whole episode moved through, and it didn't drop much of anything really).

It should at least feel seasonal with subzero nights. There could be a risk of a freezing rain event somewhere.

Next week is when things become particularly interesting, as we have a bit of a col situation for a time (between high and low pressure with dead calm air) which could really allow temperatures to plummet Sunday night - don't believe what GFSP and GFS show; late last month they were going for -1*C here under such calm conditions and in reality I was seeing lows of around -7*C. With so little mixing going on, the cold pool could become comparable to a continental one, with low dewpoints and a resilience against being shifted.

We could then see some kind of sliding low running into this low level cold early next week. Of the past few runs, only the GFSP 06z has shown the right sort of thing for a frontal snow event that affects more than a lucky few and isn't transient; the angle of the low is right for drawing in a flow form the SSE rather than S or SW. This mitigates the effect of the warm sector, though it still doesn't quite cut if for Devon and Cornwall.

As noted early this morning, ECM has a similar theme but the low stays out west so the frontal system probably doesn't affect more than areas furthest west in the UK.

UKMO has very different ideas to GFS, GFSP and ECM, in that it brings the 'parent' low down to the UK much faster, rather than having trough disruption with an extension SSE. This is a whole other ball game, in which a warm sector crosses a large portion of the UK, probably bringing a snow to rain event if it moves in fast enough, with the chance of a transition back to snow if the low drops far south enough on day 7.

Day 7 sees ECM doing a similar thing UKMO's day 6 solution, but with even more LP development - a spell of wet, rather than white, weather for much of the UK, leaving us looking for a new import of cold air as the system continues its slide SE.

Day 7 on the GFSP 06z is perhaps the best guidance as to how UKMO's sliding trough would work out, with the NE'rn third fairing best for snow, the SW only seeing rain.

I have done this more detailed summary to help keep expectations suitably low across the SW in particular - changes will need to be seen for better results there, though as usual these could leave eastern parts high and dry... it's rare for everybody to be a winner.

Also worth bearing in mind that the models do have their shortfalls when it comes to capturing cold pool/frontal system interactions, so best not to take the charts themselves too literally.

ive always found forecasts of snow at 3 days or more ahead to be misleading ie snow forecast IMBY but then the details change and there's a warm sector or a shortwave...blah blah, and at two days ahead usually also,misleading, distribution again usually ends up way less than 'casted and way different.  Only at a distance of under 24 hours, better within 12 does the accuracy of snow forecasts seem to improve markedly.

Thats a bit harsh

But they are purely for fun

"UKMO regard EC DET as progressive outlier. Strong signal for colder or much colder weather next week, albeit extremely low skill on snow risk in any one area (not even worth speculating!). MJO phase root cause for the synoptic 'flip', they say.

E.g. re PPN details Sunday; re E'wd extent of frontal progression Mon-Tues; re threat of cut-off to S leading to more pronounced E-NE solution...rapid occluding of any warm sectors in Atlantic lows expected, with 522/sub-522dam air prevailing, with attendant awkward forecast period re wintry risks."

Just copied the above two, the second of which is what prompted me to write those last two lines on my previous post.

The first one I've only just seen, and it has great implications, the largest bag of salt for once being thrown on the least cold solution 

I do wonder what they make of the UKMO 00z then, as it was even faster with the main LP arrival, though not as vigorous.

The MJO comment puts a grin on my face I can't deny - I've been banging on about it's probable impacts (weaker jet, amplification of the flow) for what feels like forever! 

In light of this, my above post does seem a bit too skeptical of the cold and snow chances - but will become more valid if there's a poor trend on the 12z runs.

Finally, so long GFS, we had some fun at times, though I'm sorry to say that foul words have been uttered more often than pleasant ones when viewing your output beyond a few days range, even if most of those were back in the earlier days of my chart watching years.

Nationwide coverage of snow on the GFSP by a week's time.

Right click open in new tab for larger version.

I'd settle for that

The Faxes are not as great at finding troughs as you imply (but then nothing is), compare how different analysis and forecast charts from yesterday were.

GFSP has become the new GFS op and is running now. On TWO I've left the charts labelled as GFSP for this run, but the chart viewer will default to showing them when you open it:

PS: I really wish the UK Met and ECM offered this level of IT service. NCEP have been outstandingly helpful in the last few months and right up there with the best private companies I've worked with in the UK. 

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

Not to mention they let you have all their data!

I used the 06z GFS for the five day forecast and forgot to mention it was the last ever run from the old GFS model.

I would prefer the greens and dark blues to extend 200 miles further south and well into the West Midlands.

 As long as it shows snow I'm sure most people will be ok. 

I would, too - the ideal scenario would be the entire country getting good coverage of snow, so nobody misses out.

Was the Jan 2010 snowfall the last time the vast majority of the UK got a good covering?

To add, any snow charts even 48 hours out are going to be subject to major change - and especially given the differences between GFSP/ECM/UKMO for the next few days, in terms of PPN forecasts

When we have charts like this less than 4 days away, trying to pin down where will see snow looks almost impossible. Some places will, though, I'm pretty sure of that!

http://www.wetterzentrale.de/pics/Rtavn901.gif

Looks like the general picture remains troughs disrupting directly over the UK, which means just a slight shift will radically alter the snow/rain prospects.

http://www.wetterzentrale.de/pics/Rtavn1261.gif

Great work as usual Brian (with help from NCEP). The free service you provide is outstanding.

Old GFS RIP
A trusted friend, at times the object of derision and ridicule, but able to influence a population in a way no other complex algorithm could. May you spend your afterlife frisking happily in spaghetti heaven.

No, surprisingly it was Jan 2013

Unsurprisingly, one of the few parts that are green is the Vale of Evesham, along with the South Coast ...



http://www.mirror.co.uk/news/uk-news/uk-weather-nasa-satellite-image-1563255

Think a lot of people are going to like this! 

Looks good for some Brian!

Better heights trying to build across Greenland into Scandinavia? 

http://www.theweatheroutlook.com/charts/gfs/12_162_mslp500.png?cb=293

That image is superb, but I hate it at the same time
That dark green semicircle at the bottom - I live in that LOL>

Note and on topic: With disruptive troughs and slack cols, uppers are less critical. I've seen heavy snow in -2 uppers but slack flow so the thermal gradient between surface and cloud level is minimal and the ppn drags temperatures down.
Looking at the synoptics between Sunday and Weds this is worth noting.