I've done a couple snowstorms with Particular, too, and I think the biggest challenge with making blizzards in Particular is getting a good, organic-looking wind and swirls.
For wind, I've just done a lot of trial-and-error with Bezier handles on wind keyframes. I've used a blizzard sound effect and tried to match the visuals to the audio for a good feel on the pacing and strength of the gusts.
For swirls, I'll set up multiple systems; a main background system, and a hero foreground system (or a set of systems). The hero system gets swirls via Particular's motion paths.
I haven't had to pile up snow in a shot, but I'd probably approach it with multiple systems like the swirls and a floor layer.
I think a tutorial here would be good -- snow seems like a slam-dunk for a general particle system like Particular, but making it look realistic requires a bit more work than you'd think at first glance.
Walter Soyka
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