I'd study some lava, and different types of magma you'll be surprised just how many textures there is in one form of element like this. It explodes, bubbles, boils, rips apart in solids and liquids due to temperature changes, there are so many things you can incorporate which aren't just the same texture! Go and look at some exploding volcanoes!
Honestly no, it's far too vague and shapeless to be considered snow, I don't think the colour choices on that thumb indicate that either - but I think she would absolutely look amazing in a snowy scene and it would really make that fire pop. Plus, on snow, reflective light often shows as blue (because of the sky being reflected) so you'd have those beautiful contrasts of cool blue with the warm orange (and a complimentary colour palette)