We've had several mornings in a row where there was a dense fog. When the fog freezes on everything, it sometimes forms what amounts to snowflakes. When the wind hits the trees, it starts to "snow". I was lucky-enough to be outside with my DSLR + 200mm zoom lens. When selecting a higher frame rate ("sports" mode), I basically followed individual snowflakes as they flew through the air. I shot over 200 of these shots until I could no-longer feel my fingers.