Abundant precipitation in the form of snow for an extended period of time, accompanied by wind with a speed exceeding 12 m / s, is classified as a hydrometeorological disaster. In such conditions, snow drifts inevitably form. Heavy snowfalls. Snow drifts, or drifts, are fanciful snow objects formed by the wind. Snow mounds resemble sand dunes and are formed on the same principle. The wind gusts the snow mass, which accumulates in the place where the air flow slows down. Snow drifts usually take the fancy shapes of ridges and slopes.