There are many products you can use to make snow and ice on your cards. The obvious choices are white flocking powder for snow and some kind of shiny glaze (like Glossy Accents) for ice. But you can get the most realistic effects by combining products. For snow on the ground, I like to mix white flocking powder with ultrafine glitter. The glitter gives it that sparkly, frozen look. For snowballs, snow drifts and ice, I like to apply chunky glitter with a top layer of Glossy Accents. It looks frosty and adds great dimension! (It also nicely conceals the rough edges of chunky glitter - bonus!)
Here's my card featuring Yumi. I made her snowball by drawing a circular shape on a scrap of cardstock and then applying Martha Stewart chunky glitter and Glossy Accents.
Here's a closeup. Hopefully you can see the sparkly accents!
Personally, I have a lot more fun playing with this kind of snow. No coat, hat, gloves or scarf required! :)
If you're one of the lucky/unlucky ones stuck inside this weekend thanks to the snow, give this technique a try!