The GFS 12z majorly downgrades snow accumulation potential for the Fri-Mon period in these parts.

Which just goes to show that we cannot be sure where & when snow will actually be falling

I would have thought it was a good thing, LP increases the risk of snow (although the situ is not preferable for lake effect precip), and the lower wind speeds and pressure mean usually marginal temps are actually suitable. The places that will perhaps not look at this so well are the ones that usually do very well from the lake effect (e.g N scotland, E scotland, NE england and coastal areas in general) while inland areas, including the south do well. 

The thing that gets me about this, is there is no actual proper cold, the uppers are cold enough for snow, but really they go for pass marks rather than merits. There is no source to any of the proper arctic air masses, instead we are stuck in pool of cold air that has no real link with the northern regions. 

Maybe we are getting some well deserved payback for last winter's horror show

I agree. But when did we last see a setup like this? Just curious.

Can we rename it 'Faux Snow'??  

It just goes to show that sometimes you can never be sure of what is around the corner. At this time last week I wasn't expecting to see model runs for the later part of January that we're now seeing, although I was hoping for a change away from the recent pattern. Perhaps we're not going to have to wait until February after all.

Its quite easy to tell that the warm sector is well to the south on this image, that doesn't guarantee snow though, in fact I would actually say its more appropriate to say that a warm sector almost guarantees it won't snow. Anyway as far as the weather on this system, that occluded front across the south west will probably be a band of snow, though it may be rain in cornwall or coastal parts. Another occluded front sits across NE england, and this one giving snow also. Apart from this mostly dry, with a few wintry showers in N scotland. 

Thanks Quantum...   very helpful. 

So far, so promising  

The threat of a push of less cold air from the west on day 5 of the UKMO run, but with the low so elongated, and the system dropped so far south by day 6, it's possible the warm sector would end up SW of the UK.

This solution is closer to recent GFSP runs, though still with a greater extent of LP development.

Speaking of GFSP, it runs a fine line in the early hours of Tuesday but with heavy precipitation and a cold low level flow from the SE... need I say more 

With better occlusion of the warm sector and the formation of LP in the Channel, even the South Coast gets in on the act Tuesday daytime.

Both of those things are in line with what the Met Office are considering for next week, based on Fergie's reports, which is a very good sign... but it is way out at +144 hours which for a snow event might as well be next year 

Seriously though, details could be very different come the day - this run just happens to be close to ideal IMBY so it's going right into Stormchaser's bank of awesome output 

It's good to have seen such a change (over the past few days) from LP powering NE to LP sliding SW for the second half of next week, as it raises the possibility of similar adjustments for what comes after - though the MJO looks less influential by then... but enough about that, the focus is on next week's potential and should remain so until we're through it 

No counting chickens yet! Its not a done deal. If the low doesnt slide we are stuffed again

Agree with last comment....  No point looking for snowfall detail at those ranges.  It can only lead to disappointment in the period leading up to when snow becomes forecastable (is that a word?)... which is t+24 at best, but mostly t+0.

Yes, it is as well to point out that the output will vary from run to run, particularly on the operational runs, so we should not take one set of runs as gospel, however tasty they might look. The 12z might look great, the 18z is the pub run, but the models often sober up for the 00z and 06z runs, leading to much wrist slashing, knashing of teeth and wailing. So please bear that in mind guys for when the next set of disappointing runs come out.

Agreed, I always appreciate your... er... full frontal analysis, Q!

And err . . (whispers). GEM
Hey why whisper. GEM! The premier model at the moment.

I've already signed the cheque. Just waiting for the details now

We had half an inch of snow on Friday afternoon 25th, but the snow turned to rain later. On the Saturday we had 11.5mm of rain with a maximum temp of 7.6C.

So yes, that small island of green probably included the Manchester area, including Cheadle Hulme.

Let`s hope we do better this year.

Pretty massive snow accum upgrade on the GFS

As always if you want to see these beautiful 1960s colours up close then right click open new tab. 

Some WTF moments viewing the charts today, a snowfest for many if the output verifies. It's not without risk though as sliders can go horribly wrong more so the further West you are, but that doesn't appear to be a problem looking at how the troughing tilts on NW/SE axis thus far. IMBY and Friday night/Saturday morning could bring a period of more organised snow before the main course from Monday-Wednesday. Think I need a lye down now.

Also highlights how useless snow accumulations charts are - as in completely. 

That's not a criticism of you Q or your work, but these things change from run to run because the model output does. I would say they might be a better, yet very rough guide as to where snow may fall, but in terms of any individual chart being used for accumulation - useless. 

Tbh sliders tend to go wrong more often for the East, because they simply slide too much, I've seen this happen way to many times. NE england is perhaps the worst place to be in this sort of setup. 

I hope by now most people understand how to interpret these charts with all the appropriate caveats, I take your point completely. The fact that this sort of thing is appearing, is not a bad thing though, it just goes to show that potential does exist. I'm really not holding up hope for my region though, I recon the action will be further south.

I havent seen the actual charts, but i did see the run through on the BBC website 6 days ahead view.  They looked delightful.  Lots of kinks and features all cold looking.

Agree entirely re potential. We do have a couple of users (Tallyho springs to mind) that hang on every chart as if it's written in law. Just thought it was worth pointing out. Enjoying your work though.