Not to steal your thread, but here's some suggestions...

This is done with Railroad Scenics "Snow" and Snow-Coat from Small Shop EU dusted over top in places for a little sparkle. You don't have to go overboard to convey the season or period and blanket your miniature and base with snow. I did this several years ago, and it won't yellow.

This one is about as heavy as I care to go - and it displays all the snow mediums I have on the workbench. It simulates icicles, new fallen snow, old crusty snow, sleet, and rainfall mixed with typical grime, dust, mud and muck tanks find themselves in over a period of several days out in the field on exercise.
Hopefully, you can get an idea of which way you want to go with your miniature with these photos.