Middle English, from Old English; akin to Old High German sturm storm, Old English styrian to stir
- 1a : a disturbance of the atmosphere marked by wind and usually by rain, snow, hail, sleet, or thunder and lightning b : a heavy fall of rain, snow, or hail c (1) : wind having a speed of 64 to 72 miles (103 to 117 kilometers) per hour (2) : whole gale — see beaufort scale table d : a serious disturbance of any element of nature
- 2: a disturbed or agitated state <storms of emotion> : a sudden or violent commotion
- 3: a heavy discharge of objects (as missiles)
- 4: a tumultuous outburst <a storm of protests>
- 5a : paroxysm
- b : a sudden heavy influx or onset
A storm (from Proto-Germanic sturmaz "noise, tumult") is any disturbed state of an astronomical body's atmosphere, especially affecting its surface, and strongly implying severe weather. It may be marked by strong wind, hail, thunder and/or lightning (a thunderstorm), heavy precipitation (snowstorm, rainstorm), heavy freezing rain (ice storm), strong winds (tropical storm, hurricane, windstorm) or wind transporting some substance through the atmosphere (as in a dust storm, blizzard, sandstorm, etc.). Storms generally lead to negative impacts to lives and property, such as storm surge, heavy rain or snow (causing flooding or road impassibility), lightning, wildfires, and vertical wind shear; however, systems with significant rainfall can alleviate drought in places they move through. Heavy snowfall can allow special recreational activities to take place which would not be possible otherwise, such as skiing and snowmobiling.