12 in B♭ minor, "Chasse-neige" (snow-whirls) is the last of twelve Transcendental Études by Franz Liszt.
The étude is a study in tremolos but contains many other difficulties like wide jumps and fast chromatic scales, and it requires a very gentle and soft touch in the beginning.
The piece gradually builds up to a powerful climax.
[1] Ferruccio Busoni stated the étude was the "noblest example, perhaps, amongst all music of a poetising nature."
He described the work as "a sublime and steady fall of snow which gradually buries landscape and people".