More from Ian Fergusson on NW. 

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.

So, that = good news 

Blimey, hadn't looked at GFSP yet. That's a bit fresh.

http://www.wetterzentrale.de/pics/Rpgfs24017.gif

Indeed Saturday night is the first chance for most with the ecm the right side of marginal this morning.

That is good stuff. Bad news for forecasters but good news for a second bite at the (glacé) cherry for those who missed out this time.

BTW I know I'm a pedant but can we do Ian the favour of spelling his name right? It's Fergusson with a double s. 

Being so close to the south coast I still worry about the marginal nature of all of this.  But that's far too IMBY.  The trend is still good overall.

06Z GFS has an interesting feature crossing the SE on Sunday night. Marginal but could deliver:

http://www.wetterzentrale.de/pics/Rmgfs1143.gif

Then temps struggling to go positive for many areas on Monday

http://www.wetterzentrale.de/pics/Rmgfs1294.gif

The lower temperatures towards the west are in all probability to the snow fields around Mattys house of course reflective heat in full action But not much going on towards the Chelmsford area as usual.  

06Z GFS looks pretty messy. But in a good way.

http://www.wetterzentrale.de/pics/Rtavn1681.gif

Then that low trots off to the south and brings in an easterly. "Textbook", as Alan Partridge would say. 

http://www.wetterzentrale.de/pics/Rtavn1921.gif

Oddly on this run the upper temps being dragged into SE England are rather high, the 204 chart shows - forecast as rain :(

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=204&mode=1

Yes grew up in West Sussex Billingshurst area and it was more often than not the wrong side of marginal in the 90s anyway. But West Sussex has had a couple of good snow events this decade so you never know.

Some cold nights coming up next week - esp over Scotland -13c

Oh don't get me wrong - other than last year (and this year so far) this decade has been great for snow down here.   I'm just wary of getting too excited whilst the overall picture is marginal - being down here, unless it's a screaming NE wind, we're always at risk of being the wrong side of the line.   At least we've got the downs to help 

Yes my mistake corrected. To have a Meto Pro on these forums is incredibly worthwhile especially at a time like this.

That was probably the last ever run of the still current GFS model. Agree with the comments that it was quite cold and messy, and fits in well with the generally expected picture for next week. 

Yep - one of those setups which could either deliver some incredible snow (with the borderline temps and extra moisture in the mix) or cold rain.  It'll hinge on very small daily variations in conditions.  Fascinating to watch - a nightmare to forecast.

What a way for the OP to go out!

Will the Parallel take over as the Op from the 12z?

These features moving down from the north in ambient cold makes for an incredibly interesting period of weather. I can understand some of the caution from the immediate south coast crew, any SW'ly onshore drift ahead of the systems can tip things the rainy side of marginal at times.

The key is to avoid the weak warm sectors, eastern half of the UK currently look best placed.

I think there is a lot to optimistic about here. Snow fell here this morning above 100 metres with a fresh SW'ly wind off the channel in 524dam air with 850Hpa's of -5c and 925Hpa's of +1c.

This weekends parameters look a tad colder than this with less maritime influence.

The biggest snowfalls are the marginal ones.

Longer term the option of the easterly is still there for the SE to get excited about.

If the GFSP 6z is accurate, MBY will have snow cover from Friday night through to the end of the run, with parts of lowland NW England having 20cm+

T+66

http://expert-images.weatheronline.co.uk/daten/proficharts/en/gfs25/2015/01/14/basis06/ukuk/weas/15011700_1406.gif

T+198 (the peak, and a thing of beauty )

http://expert-images.weatheronline.co.uk/daten/proficharts/en/gfs25/2015/01/13/basis18/ukuk/weas/15012212_1318.gif

T+360

http://expert-images.weatheronline.co.uk/daten/proficharts/en/gfs25/2015/01/13/basis06/ukuk/weas/15012906_1306.gif

Pity that won't happen, but nice eye-candy, and it is a consistent theme from the GFSP over the past few runs

Remarkable consistency for the next 7 days from the GEFS:

Its been a while since we had such tight packed members for so far into the future.

Looks good out to 168h.Strohg showing of Scandi /Iceland HP ens,plus a couple of cold Mid Atlantic HP.This give roughly a 50:50 split of cold:warm Ens.

After that its downhill with 75% of ENS at 240h being Atlantic driven rising to 80% at 360h.

So best to enjoy the 7 cold days approaching!

http://expert-images.weatheronline.co.uk/daten/proficharts/en/2015/01/14/basis06/ukuk/rart/15012012_2_1406.gif

Snow moves into the NW on Tuesday

http://expert-images.weatheronline.co.uk/daten/proficharts/en/2015/01/14/basis06/ukuk/rart/15012018_2_1406.gif

Across into England

http://expert-images.weatheronline.co.uk/daten/proficharts/en/2015/01/14/basis06/ukuk/rart/15012100_2_1406.gif

Down into the SE

http://expert-images.weatheronline.co.uk/daten/proficharts/en/2015/01/14/basis06/ukuk/rart/15012106_2_1406.gif

Another area comes in from the West

http://expert-images.weatheronline.co.uk/daten/proficharts/en/2015/01/14/basis06/ukuk/rart/15012112_2_1406.gif

Moves across England

Of course depending if GFS is correct