snowfall

The act of snowing. The term is also used to express the amount of snow that has accumulated on the ground at one time as a consequence of that action. The intensity of snowfalls is highly variable. Weather observers establish the following division into four categories: 1) very light snowfall, in which flakes fall very sparsely, not fully covering the terrain; 2) light snowfall, in which visibility of more than one kilometer is possible; 3) moderate snowfall, in which horizontal visibility falls between 500 and 1000 m; and 4) heavy snowfall, characterized by the fall of a large quantity of large snowflakes, which reduces horizontal visibility below 500 m. The rate of snow accumulation on the ground - greater or lesser depending on the intensity of the snowfall - allows a similar classification to be established for the fallen snow.