Squall and Gusts

A squall is a sudden, sharp increase in wind speed lasting minutes, contrary to a wind gust lasting seconds. They are usually associated with active weather, such as rain showers, thunderstorms, or heavy snow. Squalls refer to the increase in the sustained winds over that time interval, as there may be higher gusts during a squall event. 

A gust is a brief increase in the speed of the wind, usually less than twenty seconds. It is of a more transient character than a squall, which lasts minutes, and is followed by a lull or slackening in the wind speed. Generally, winds are least gusty over large water surfaces and most gusty over rough land and near high buildings.