Yeah, I was driving through London yesterday, in an attempt to avoid the static M25. Six hours from Thetford to Reading. Ouch. (Normally takes just under three).I had to abandon my BMW at the side of the road a few years ago.
Very wide low profile tyres + big engine + snow is not a good mix
Very similar here in London, snowed for less than an hour and it's up to 10cm in places.
As for BMW - they are hopeless in the snow unless prepared for it with winter tyres etc. The same goes for most rear-wheel drive cars - most of the vehicles abandoned around here are premium German brands. I only managed to get mine home because I wrangled with the traction control until it allowed me to spin the wheels fast enough to melt the snow underneath them and get enough grip to catapult me forwards, after which I had an epic hundred meter sideways power slide...
Fun... kinda.