Frost

Frost is a thin, white layer of ice that forms on surfaces when the air is cold and full of moisture. It happens when the temperature drops below the freezing point of water, which is 0°C (32°F). The tiny water vapor in the air turns directly into ice crystals without becoming liquid first. This process is called deposition.

Frost can form on many surfaces, such as grass, leaves, cars, or windows. On a clear, calm night, the ground loses heat quickly, and the air near it becomes colder. When this air touches cool surfaces, it makes the moisture freeze, creating beautiful icy patterns. Frost on windows often looks like delicate feathers or branches, called frost flowers.

There are different kinds of frost. Hoar frost is the most common type, made of white, feathery ice crystals. Black frost happens when the temperature is very low but there is not enough moisture in the air to make visible ice—it still damages plants because the water inside them freezes. Rime frost forms when fog or mist freezes onto surfaces in windy, freezing weather.

Frost can be both beautiful and harmful. While it makes the world look sparkly and magical, it can also damage plants by freezing the water inside their leaves and stems. Farmers often worry about frost during spring, when young crops are just starting to grow. In some cases, they use heaters or sprinklers to protect their plants from freezing.

People often see frost in cold seasons like autumn and winter, especially in places with clear skies and little wind. When the sun rises, frost melts back into water as temperatures warm. Whether it’s on a windowpane or a leaf, frost reminds us how air, water, and temperature work together in nature’s frozen artwork.