As I write, the car park here at Autocar Towers is steadily filling with slushy, light snow.

At the moment it is nothing that's going to significantly trouble our travels to and from the office, although we've heard tales that the road network not far from us has started to choke up.

In any case, I'm fortunate to be running an all-wheel-drive Subaru XV at the moment. Maybe my car's rugged capability is the reason I was the one of the first to reach the office this morning.

When I turned up, I parked my blue XV next to the orange BMW M135i you can see in the first row of vehicles. About 30 minutes later the snow started and has carried on falling consistently since then.

As a bit of light-hearted fun, I've been trying to work out the reason for a strange anomaly that's developed over the past couple of hours.

Curiously, the BMW's bonnet has remained remarkably clear of snow, even though the white stuff has started to coat the surfaces of my diesel crossover and most of the other cars.

I'm sure there's some logical explanation that I'm not clever enough to comprehend. Given that the BMW had been parked up for longer than the XV, it can't be that the engine bay is still warm and has melted any snow that gathered on the bonnet.

Does anyone out there know why it could be? Is it simple chance or positioning? Is BMW using some ultra-gloss paint treatment that repels snow? Is it the colour of the paint? Note from the photograph taken by our intrepid chief photographer, Stan Papior, that the similar-coloured SsangYong on the same row is also virtually snow-free.

Apologies in advance if there's a glaringly simple reason. I'll blame it on brain freeze...