High-res still for a poster, miniature looking snow

I am working on a poster design for a rap band in Winnipeg. It is their video release and the video is all stop motion animated with cartoonish versions of the rappers. The band asked me to include a still of the models in the poster. I considered painting the background as snow, but I’ve been getting into Blender lately and I think it’d be perfect for this job.

What I am looking for is a snowy scene, preferably verticle, high res, 3300x5100.

The thing I have no idea how to do (and I am trying to figure out on my own) is fluffy snow, snow that looks fake, for these figures to stand in.

I am sure someone who knows compositing and sub-surface could whip this up in 10 - 20 minutes. Sadly, I am still just a beginner with 3D tools.

So… what is it you want exactly? I see a vertical snow wall that is low quality and fake looking… So… you want a vertical snow wall or a side of a mountain/wall of snow?