A storm is a period of violent weather with strong winds, heavy rain, snow, or thunder and lightning. During a storm, the sky darkens, trees bend and sway, and you might hear rain hammering against windows or wind howling around buildings. Storms can be as brief as a summer thunderstorm that passes in twenty minutes, or as prolonged as a winter blizzard that dumps snow for days.

Different types of storms have different names: hurricanes form over warm ocean waters and spin with devastating winds, tornadoes create violently rotating columns of air, and thunderstorms fill the sky with lightning and booming thunder. Some storms bring welcome rain to dry areas, while others cause floods, damage buildings, or knock down power lines.

The word also describes any sudden, intense outburst or upheaval. An argument might storm through a quiet room, changing the mood instantly. Someone might storm out of a meeting in anger, moving quickly with visible emotion. In medieval times, people might storm a castle, attacking it with sudden, overwhelming force. A controversial decision might create a storm of protest, with many people expressing strong objections. In this sense, storm captures that same feeling of sudden intensity and power that makes actual weather storms so memorable.