A snowdrift is a pile or bank of snow created by the wind. When wind blows across snow-covered ground, it pushes loose snow along until something blocks its path: a fence, a building, a hedge, or even a parked car. The snow accumulates there, sometimes building into mounds taller than a person.

Snowdrifts form because wind doesn't blow snow evenly. Just as water flowing in a stream deposits sand and pebbles in certain spots, wind deposits snow where obstacles slow it down or where the land's shape creates sheltered areas. A snowdrift might be shallow on one side of a barn but pile up ten feet high on the other, depending on which way the wind blew.

These drifts can create serious problems. A snowdrift across a road can trap cars or block emergency vehicles. Farmers worry about snowdrifts burying livestock or blocking barn doors. But snowdrifts also help: they insulate small animals sheltering underneath, provide moisture when they melt in spring, and create spectacular winter landscapes. After a blizzard, you might see fields where the ground is nearly bare in some spots but buried under massive snowdrifts in others, all shaped by the wind's invisible patterns.