I'd be VERY cautious over depths from this event. Chris Fawkes latest forecast just showed on news 24, or in his words 'snow will turn to rain over 'Wales & West Midlands this afternoon' which the graphic showed from around 1-5pm. Last night the road was wet and thus we had 2-3CM snow accumulated, when around 7 or 8CM probably fell. The second a car drove over this and people walked on the pathways everything turned to slush. I'd expect tonight to be a carbon copy of last night.
The later the better the snow comes. Less people on the road then.