Thank you for asking, this was my first post to the forum and first scene after not using 3D modeling programs for approx 3 years. So it is nice if someone thinks anything good of my render
I used a displace and subdivision surface modifiers on a plane. The displace modifier used a 4096x4096px png image that i painted to replicate the snow effect. The actual plane that uses the modifier only has the ditches and the slope modeled to it. I saw the technique on YouTube and decided to give it a go on my own.
Here you can see the displacement image that i created on Gimp http://i.imgur.com/pY91kmCl.png
I used standard Gimp brushes on on top of each other, nothing fancy. Almost everything is on separate layers so i could easily tweak the brightness of all the different snow piles and crumbles that i drew. The tire marks i found online and placed them so the camera could catch them.
The falling snow was made with a particle system that emitted cylinders with 3 sides, those cylinders had a partly transparent shader mix on them. The real work was made by motion blur
The snow material just has a noise texture as a bump/normal on top of Diffuce and Glossy shaders mixed together. Honestly i could have made far better job with the node editor and the lighting wasn’t to my liking, but i got frustrated and decided to settle at that.
And living in a country that has snow for half of the year sure helps in attempts to recreate it in 3D