Monday: Some snow in the northern isles and northern scotland

Tuesday: Band of rain pushing south with risk of snow on its northen edge very briefly into the evening for parts of the north midlands possibly. Snow showers for the far north.

Wednesday: Snow showers for parts of Scotland, risk of a polar low for the extreme NW?

Thursday: Risk of snow for large parts of England north of the midlands. Many areas will see the snow turning to rain, some places likely will not.

Friday: ?????

Saturday: ????

Sunday: ????

Lots of uncertainty regarding timing, where the heaviest precipitation will be and what happens to the front after it comes into Northern England. Those factors will determine  level of disruption, whether low levels are affected and whether it turns to rain.    

Monday:No

Tuesday:No

Wednesday:No

Thursday:No

Friday:No

Saturday:No

Sunday:No

Repeat 30 times starting beginning of November to end of February

Look for pools of cold air (say -4C or -6C contours) seemingly appear out of nowhere just north of the front (i.e where the T850 gradient is), so essentially from south to north you end up with warm, cold, slightly less cold.

Anyway another thing to watch for is that big big T850 gradient; big gradients mean coherent fronts and they are more likely to be snow makers. Combine the warm, cold, slightly less cold pattern with a big gradient and you have a best case scenario (provided you are in the cold part). One of the most annoying things is being in the 'slightly less cold' bit and ending up with light rain rather than heavy snow; unfortunately that can happen if it ends up being marginal.

I would have assumed evaporative cooling at lower levels would lead to a warming at the 850 level. (Increased water vapour)

UKMO: Mid wales to SE England

GEM: Mid wales to Suffolk

GFS: North wales to Nofolk

ARPEGE: North wales coast to Nofolk coast (slightly north of GFS)

ICON: Merseyside to Lincolnshire

And this is only the position of the front on Thursday. Don't even get me started about intensification and secondary lows e.c.t.

🤣

Pretty much sums it up for us Kent Folks, although we did manage a fleeting wintry spell a few weeks ago but almost missed it by blinking.

Fair to say, I won't be losing much sleep over this one. 

For sure it does moisten the atmosphere, but the ascent and condensational heating happens at an angle if that makes sense, since you get ascent over the surface warm front, and where the precip is the ascent tends to be weaker or you might even get some descent.

To be fair, over the past 40 years we have had a few good snowfalls. I recall one where we had an impressive crop of "snow rollers".

Two apposite local weather sayings:

'February fill dyke, be it black (heavy rain) or be it white (snow)'.

'A February Spring is worth nothing'.

Edit: here is a WRF cross section that goes from left to right, SW to NE.

https://www.meteociel.fr/modeles/coupewrf/coupegfs_486_502_521_331_63_0_1000_250.png

Note the warm nose w ith T850s as high as +2.5C and surface temps below 0C.

Forget the -5C line for this event basically.

EDIT2: This is also the scenario that should produce very high quality snow if it comes off. Small snow crystals fall through the warmer layer and get sticky producing huge conglomerate flakes which then firm up as they fall through the cold layer below!

Cold front is 100 miles or so further south than forecast! Good start!

https://www.meteociel.fr/modeles/coupewrf/coupegfs_393_527_564_379_72_0_1000_250.png

We need to have a very serious conversation about freezing rain. Some places see literal hours on end of freezing rain. Real risk of real ice accumulation here. 

Remarkable, Alaro has snow at T850s of 2C.  

I've seen another one of the leading models do something similar (850s were closer to 3 or 4 IIRC) in the past. I flagged it up with the agency concerned but never really got to the bottom of it.

It is theoretically possible of course. If the temp maxes out at 850hpa and the freezing layer is say only 30mb thick, then you'd get snow from that. And while 3-4C is very very extreme, I think it does occasionally happen in the US (strong warm front coming into cold air combined with some orographic jiggery pokery).

For this event, I don't think snow will be falling at those T850s but the surface warm front decoupling from the upper front combined with decreasing wind/evap cooling could produce +ve T850 snow, in 2010 I saw snow at +1C so it does happen even here.

The bigger worry is that when you see snow falling at positive T850s that also probably means a significant freezing rain band. I'm suprised the metoffice haven't mentioned it.

EDIT: I should add that all the high res models that are in range (except the UKV) are producing positive T850 snow, so it isn't just one model. Unfortunately the met does seem to have a bias towards their own model, if the UKV was showing this then there would definitely be a freezing rain mention.

 https://www.meteociel.fr/cartes_obs/gens_display.php?ext=1&x=258&y=16 

Haven't seen the ECM ensembles but on the mean chart the 0c Isotherm is straddling my location on Saturday 12am, ECM Op has it much further North so likely quite a bit of scatter there too. 

It's almost certain that the hills will kill off any precipitation for this area.

Yellow warnings move the southern boundary further north…

https://www.meteociel.com/modeles/arpege.php?ech=50&mode=42&map=300