Dupont instructor, Caroline Marsland gave a demo on painting snow on Dec 13/17. She used acrylic paint mixed in big batches of colours and started with a quick sketch. She informed us that snow was painted cool the foreground and warmer in the background. It works dark to light. Very often tracks in the snow lead your eye into the picture.
Snow reflects all the colours around it. Watch out using grey as it kills the picture. Colour makes snow look bright, especially cad orange , yellows and pinks. Cobalt blue gives a clean look. Different whites can be used for buildings. Build up your painting and check tonal values.