Realistic snow blizzard using particles?

Does anyone have any pointers for creating a realistic blizzard scene using particles in Motion 4? I've got a nice photo of a desolate Arctic scene, I now want to turn into into a near-white-out blizzard with the snowflakes being hammered into the camera by the wind, but I've never found any tutorials for creating realistic "organic" particle effects in Motion.

I'm playing around with the Snow Blizzard one at the moment, but it's just too smooth. The particles need to have a much more realistic random motion, to look like they're really being whipped around by a strong wind. I'm not sure how to achieve that, or if it's even possible in Motion without ponying up for an expensive particle plugin.

Blizzards tend to fluctuate a lot, with the intensity going up and down in random bursts, and changing directions.

To get a more realistic feel, try to animate some of the parameters (by adding parameter behavior or using keyframes), or work with several emitters on top of each other.

It will take a lot of experimenting, but it's certainly possible to do.