I live in Quebec. The conditions aren't as extreme as yours but still, snow is there for abouth 6 months. Adapt to your environnement : go run in high amount of snow, build yourself a sled and put some weight on it, and walk around, pulling the thing. Or just pick up ice chunk in your arms, and lift them, throw them, walk with them. As for more technical training, just be really careful, don't do anything stupid. You can still train your techniques, you just have to be careful.
Oh, and Snowkour sucks. It's Parkour. Parkour is the same thing, wether it's sunny, raining or snowing :P