Or rather, do not paint
the snow white
The Impressionists, interested, as they were, in light and texture and form, rarely used white paint. So how, you might wonder, did they paint snow?
The next time you have the chance to observe a snow-cloaked landscape, take a moment to look where shadows fall. Hey, lookit that, the snow isn't white at all! Colorless, it reflects what is around it, or what casts a shadow onto it. Snow appears white because it reflects sunlight, or clouds. When the sun has gone down, sometimes the snow turns blue. Shadowed by trees, or sculpted by the wind, snow will take on shades of indigo and gray and even black.
So, don't eat the yellow snow, and don't think that snow is white, either.